DESC:FIELD OF THE DISCLOSURE

The present disclosure relates to fuel-based engines. Particularly, the present disclosure relates to systems and methods for controlling an engine using Hydrogen enriched Compressed Natural Gas (HCNG) and systems thereof.

BACKGROUND

The usage of natural gas in internal combustion engines involves various difficulties, like weak lean-burn ability, low flame speed, and ignitability, and therefore, for compressed natural gas (CNG) in engines, there is an engine efficiency sacrifice at low loads and high levels of hydrocarbon (HC) and carbon monoxide (CO) emissions which cannot be solved without using expensive after-treatment equipment. Therefore, the usage of an additional gas blended with the existing CNG fuel can enhance the characteristics of the combustion of natural gas with lesser carbon emissions.

Low-carbon or carbon-free fuels become a need of the hour for the transportation sector throughout the world. Hydrogen is one such fuel that can significantly reduce the carbon footprint of the mobility sector, so hydrogen blended, or Hydrogen enriched Compressed Natural Gas (HCNG) can be an alternative to fossil fuels. Hydrogen has some inherent characteristics such as a higher-octane number, a higher flame velocity, no carbon content, and a higher heat content, which facilitate the use of hydrogen along with the natural gas. The usage of HCNG as a fuel improves the performance of an engine and significantly decreases emissions.

Hence, there is a requirement for HCNG fuel engines that effectively reduce the discharge of greenhouse gases at a lower cost. However, existing engines requires various hardware modifications to use HCNG as a fuel along with conventional fuels. Accordingly, a system or a method can be developed that can use the components of existing engines without any hardware modifications to provide better fuel economy and lesser carbon emissions as compared to the existing engines.

SUMMARY

The present disclosure provides methods and systems for controlling an engine using Hydrogen enriched Compressed Natural Gas (HCNG) as a fuel in a vehicle without any hardware modification in the existing engine.

The present invention discloses a system for controlling a Hydrogen enriched Compressed Gas (HCNG) engine having at least one processor. The at least one processor is configured to communicate with at least one of an accelerator pedal, an intake throttle valve, a fuel injector, and a lambda sensor. The at least one processor is configured to determine a default output value of an air supply from the intake throttle valve based on a torque demand generated through the accelerator pedal. The at least one processor is further configured to compute a corrected output value of the air supply from the intake throttle valve based on a first set of parameters associated with the HCNG engine and one or more ambient conditions. The at least one processor is then configured to estimate a default value of a fuel injection quantity based on the corrected output value of the air supply. Further, the at least one processor computes a corrected value of the fuel injection quantity based on an output from the lambda sensor, a second set of parameters associated with the fuel injector and the one or more ambient conditions. The at least one processor is then configured to supply air based on the corrected output value and fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine to achieve a final torque equivalent to the torque demand.

In an embodiment, a system for controlling a Hydrogen enriched Compressed Gas (HCNG) engine is disclosed. The system includes at least one processor adapted to communicate with at least one of an accelerator pedal, an ignition coil, a battery, and a spark plug. The at least one processor is configured to determine a default output value of a dwell time of the ignition coil based on a torque demand generated through the accelerator pedal. Further, the at least one processor computes a corrected output value of the dwell time based on a voltage supplied by the battery to the ignition coil. The at least one processor, then, determines a default output value of an ignition angle of the spark plug based on the corrected output value of the dwell time and the torque demand. Further, the at least one processor computes a corrected output value of the ignition angle based on a set of primary parameters associated with the HCNG engine and one or more ambient conditions. The at least one processor is configured to actuate the spark plug to generate a spark based on the corrected output value of the dwell time and the corrected output value of the ignition angle.

In another embodiment, a method for controlling a Hydrogen enriched Compressed Gas (HCNG) engine by at least one processor is disclosed. The method includes the steps mentioned as follows. Determining a default output value of an air supply from an intake throttle valve based on a torque demand generated through an accelerator pedal, by the at least one processor. Computing a corrected output value of the air supply from the intake throttle valve based on a first set of parameters associated with the HCNG engine and one or more ambient conditions, by the at least one processor. Estimating a default value of a fuel injection quantity based on the corrected output value of the air supply, by the at least one processor. Computing a corrected value of the fuel injection quantity based on an output from a lambda sensor, a second set of parameters associated with an fuel injector and the one or more ambient conditions, by the at least one processor. Lastly, supplying air based on the corrected output value and fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine by the at least one processor to achieve a final torque equivalent to the torque demand.
In another embodiment, a method for controlling a Hydrogen enriched Compressed Gas (HCNG) engine by at least one processor is disclosed. The method includes the steps mentioned as follows. Determining a default output value of a dwell time of an ignition coil based on a torque demand generated through an accelerator pedal, by the at least one processor. Computing a corrected output value of the dwell time based on a voltage supplied by a battery to the ignition coil, by the at least one processor. Determining a default output value of an ignition angle of a spark plug based on the corrected output value of the dwell time and the torque demand, by the at least one processor. Computing a corrected output value of the ignition angle based on a set of primary parameters associated with the HCNG engine and one or more ambient conditions, by the at least one processor. Lastly, actuating the spark plug by the at least one processor to generate a spark based on the corrected output value of the dwell time and the corrected output value of the ignition angle.

To further clarify advantages and features of the present disclosure, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings:

Figure 1 illustrates a block diagram of a system for controlling an engine using HCNG as a fuel having HCNG sensors and actuators layout, according to an embodiment of the present disclosure;

Figure 2 illustrates a block diagram depicting operation of the system for controlling a supply of air and fuel to the engine using HCNG through at least one processor, according to an embodiment of the present disclosure;

Figure 3 illustrates a block diagram depicting operation of the system for controlling an ignition timing of the engine using HCNG through the at least one processor, according to an embodiment of the present disclosure;

Figure 4 illustrates a flow chart of the system for controlling a lambda value of the system through the at least one processor, according to an embodiment of the present disclosure;

Figure 5 illustrates a flow chart of the strategy to switch the lambda value based on coolant temperature through the at least one processor, according to an embodiment of the present disclosure;

Figure 6 illustrates a graphical representation of the switching of the lambda value based on coolant temperature for improving NOx conversion through the at least one processor, according to an embodiment of the present disclosure;

Figure 7(a) illustrates exemplary details of emission data of carbon monoxide, recorded during the experimentation of the system, according to an embodiment of the present disclosure;

Figure 7(b) illustrates exemplary details of emission data of methane, recorded during the experimentation of the system, according to an embodiment of the present disclosure;

Figure 7(c) illustrates exemplary details of emission data of non-methane hydrocarbon, recorded during the experimentation of the system, according to an embodiment of the present disclosure;

Figure 7(d) illustrates exemplary details of emission data of oxides of nitrogen, recorded during the experimentation of the system, according to an embodiment of the present disclosure; and

Figure 7(e) illustrates exemplary specific fuel consumption data recorded over the World Motorcycle Test Cycle (WMTC) tests of the system, according to an embodiment of the present disclosure.

Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present disclosure. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

While the embodiments in the disclosure are subject to various modifications and alternative forms, the specific embodiment thereof has been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.

It is to be noted that a person skilled in the art would be motivated from the present disclosure to modify methods for controlling an engine for using Hydrogen enriched Compressed Natural Gas and systems thereof, as disclosed herein. However, such modifications should be construed to be within the scope of the disclosure. Accordingly, the drawings show only those specific details that are pertinent to understand the embodiments of the present disclosure, so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

The term ‘system’ refers to a system for controlling the engine parameters for using Hydrogen enriched Compressed Natural Gas (HCNG) as a fuel in a vehicle.

The term ‘engine’ may interchangeably be used with the term ‘HCNG engine’.

The term ‘at least one processor’ may refer to, but is not limited to, a microcontroller or any logic circuitry adapted to control the engine and associated components for using Hydrogen enriched Compressed Natural Gas (HCNG) as fuel. Further, the term ‘at least one processor’ may also include a control unit or a programming unit including protocols to monitor and control the sensors. The “at least one processor” may include a Printed Circuit Board (PCB) which is further connected to a power source for supplying the power to “the at least one processor”.

The present disclosure provides a method and a system for controlling an engine for use of Hydrogen enriched Compressed Natural Gas (HCNG) as a fuel in a vehicle without any hardware modification in the existing engine. Herein, HCNG fuel contains hydrogen content between a range of 15% to 25% by volume in Compressed Natural Gas. The vehicle includes, but is not limited to, a heavy-duty vehicle and/or a light commercial vehicle. The vehicle may include a crankshaft, a camshaft, a flywheel, an accelerator pedal, an ignition coil, a spark plug, a fuel injector, a fuel rail, and an exhaust system.

Referring to Figure 1, a system 100 is adapted for controlling an engine 114 for using HCNG as a fuel in a vehicle (not shown). The system 100 may include at least one processor 115 adapted to optimize various engine operating and design parameters for the use of HCNG as a fuel. Herein, the term “engine operating and design parameters” is also referred to as “desired parameters”. The system 100 further includes a plurality of sensors 101-110. The plurality of sensors 101-110 includes an accelerator pedal sensor 101, a crank position sensor 102, a cam sensor 103, a T-MAP sensor 104, a fuel rail pressure-temperature (RPT) sensor 105, a coolant pressure sensor 106, a coolant temperature sensor 107, a vehicle speed sensor 108, a HCNG tank pressure and temperature sensor 109, and a lambda sensor 110.

The plurality of sensors is adapted to monitor, but not limited to, an accelerator pedal position, a crank position, a cam position, an intake manifold pressure, an intake manifold temperature, a fuel rail pressure, a fuel rail temperature, a throttle position, a coolant pressure, a vehicle speed, a HCNG tank pressure, and a lambda value.

Based on the inputs of the plurality of sensors 101-110, the at least one processor 115 controls at least one including an intake throttle valve 111, and a fuel injection quantity and/or fuel injection duration of a fuel injector 112, and an ignition timing of a spark plug 113 for using HCNG as a fuel in the existing engine 114.

The system 100 further includes a high-pressure HCNG regulator (not shown), and a HCNG cylinder (not shown). The HCNG cylinder (not shown) is adapted to store the HCNG. The HCNG cylinder (not shown) has the high-pressure HCNG regulator which is further connected to the engine 114. The engine 114 may include a fuel rail (not shown) with the fuel injector 112 and an ignition coil (not shown). The fuel rail (not shown) and the ignition coil (not shown) are connected to the at least one processor 115 through a plurality of actuator control wires. The at least one processor 115 is also connected to the intake throttle valve 111, the fuel injector 112, and the spark plug 113.

The at least one processor 115 is a central unit of the system 100, which controls an opening and a closing of the intake throttle valve 111, an injector pulse width of the fuel injector 112, and the ignition timing of spark plug 113 based on the inputs received from a plurality of sensors for meeting the desired performance and emissions.

The at least one processor 115 can be a single processing unit or several units, all of which could include multiple computing units. The at least one processor 115 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. Among other capabilities, the at least one processor 115 is adapted to fetch and execute computer-readable instructions and data stored in a memory.

The memory may include any non-transitory computer-readable medium known in the art including, for example, volatile memory, such as static random-access memory (SRAM) and dynamic random access memory (DRAM), and/or non-volatile memory, such as read-only memory (ROM), erasable programmable ROM, flash memories, hard disks, optical disks, and magnetic tapes.

Modules, amongst other things, include routines, programs, objects, components, data structures, etc., which perform particular tasks or implement data types. The modules may also be implemented as, signal processor(s), state machine(s), logic circuitries, and/or any other device or component that manipulate signals based on operational instructions.

Further, the modules can be implemented in hardware, instructions executed by a processing unit, or by a combination thereof. The processing unit can comprise a computer, a processor, such as the at least one processor 115, a state machine, a logic array, or any other suitable devices capable of processing instructions. The processing unit can be a general-purpose processor which executes instructions to cause the general-purpose processor to perform the required tasks or, the processing unit can be dedicated to performing the required functions. In another embodiment of the present disclosure, the modules may be machine-readable instructions (software) which, when executed by a processor/processing unit, perform any of the described functionalities.

The plurality of sensors 101-110 is adapted to monitor and control the desired parameters for meeting the target performance and emissions of the engine 114. The plurality of sensors 101-110 are explained in detail in the paragraphs mentioned below.

The accelerator pedal sensor 101 is a potentiometer-based device, may include two potentiometers inside a body of the accelerator pedal sensor 101 with a cross configuration. The accelerator pedal sensor 101 is adapted to determine a demand from a driver to achieve the required power. Herein, the voltage of the potentiometers varies based on an actuation of the pedal of the vehicle (not shown) by the driver, and the change in voltage signal is being identified by the at least one processor 115 as change in driver demand for torque and power.

The crank position sensor 102 is a Variable Reluctance (VR) type sensor adapted to determine a missing tooth offset from a Top Dead Centre (TDC) of the engine 114 and to define speed of the engine 114. The VR-type sensor provides a sign wave form of signal to the at least one processor 115. It may be determined at every 360 degrees of rotation of the crank shaft, the missing tooth occurs on a crank wheel (not shown) or the flywheel (not shown). Whenever the missing tooth comes in front of the crank position sensor 102, there is no signal from the crank position sensor 102 then. Further, the at least one processor 115 is adapted to measure the time difference between the occurrence of the missing teeth to calculate the Revolutions Per Minute (RPM) of the engine 114. Further, a feedback of the RPM is sent to the at least one processor 115, which can use the RPM output from the crank position sensor 102 for controlling the engine 114.

The cam sensor 103 is a Hall-type sensor adapted to work on the principle of hall effect for determining a cam lobe position to identify a phase of the engine 114 for determining an injection angle and an ignition angle. Based on the calibration of offset of the angles, the at least one processor 115 may determine the actual compression at the TDC of the engine 114 to start the fuel injection duration and the ignition timing.

An intake manifold pressure sensor is a radiometric output sensor connected with the at least one processor 115 through wiring. The intake manifold pressure sensor converts the absolute pressure into an electrical signal, and then transmits the electrical signal to the at least one processor 115. Further, an intake manifold temperature sensor is a resistive sensor, adapted to convert the temperature into an electrical signal, and then transmit the electrical signal to the at least one processor 115. In an embodiment, the manifold pressure sensor and the manifold temperature sensor are coupled to form a single unit which is the T-MAP sensor 104. The T-MAP sensor 104 is adapted to calculate the density of air entering inside the engine 114.

The fuel rail pressure sensor is a radiometric sensor, adapted to convert the gas pressure of the fuel rail into the electrical signals, and then transmit the electrical signal to the at least one processor 115. Further, the fuel rail temperature sensor is a resistive-type sensor. The fuel rail temperature sensor is adapted to convert temperature of the fuel in the fuel rail into the electrical signal, and then transmits the electrical signal to the at least one processor 115. In an embodiment, the fuel rail pressure sensor and the fuel rail temperature sensor are coupled to form a single unit that is the fuel rail pressure and temperature sensor 105. Based on the inputs of fuel rail pressure and temperature sensor 105, the at least one processor 115 calculates a density of HCNG available in the fuel rail. The density of HCNG is used to calculate the injection time based upon the calculated requirement of fuel along with compensation required based on the feedback from the lambda sensor 110.

The coolant pressure sensor 106 is a resistive-type sensor, adapted to convert the coolant pressure into an electrical signal. Further, the coolant pressure sensor 106 transmits the electrical signal to the at least one processor 115. The coolant pressure sensor 106 may determine the coolant pressure in the engine 114, which is used for further calculation, and as an input for different functionalities of the at least one processor 115.

The coolant temperature sensor 107 is a resistive-type sensor, adapted to convert the coolant temperature into an electrical signal. Further, the coolant temperature sensor 107 transmits the electrical signal to the at least one processor 115. The coolant temperature sensor 107 may determine the engine temperature, which is used for further calculation, and as an input for different functionalities of the at least one processor 115.

The vehicle speed sensor (VSS) 108 operates on the principle of the Hall effect. The VSS 108 is usually mounted on a gearbox (not shown) of the vehicle (not shown). The VSS 108 provides information regarding the vehicle speed to the at least one processor 115.

The hydrogen storage tank pressure sensor may be a hydrostatic (gauge), a capacitance, a resistive, or an ultrasonic sensor. The hydrogen storage tank pressure sensor allows for real-time tank level measurement. The hydrogen gas when expands provides a cooling effect which leads to a change in temperature. Hence, the hydrogen storage tank temperature sensor detects the change in temperature of the HCNG inside the HCNG storage tank. The hydrogen storage tank pressure sensor and the hydrogen storage tank temperature sensor are coupled together to form the hydrogen storage tank pressure and temperature sensor 109. The hydrogen storage tank is further connected to the high-pressure HCNG regulator. The high-pressure HCNG regulator is further connected to the at least one processor 115.

The lambda sensor 110 is adapted to provide feedback to the at least one processor 115 regarding the air-fuel ratio on which the engine 114 is running currently. The lambda sensor 110 measures the oxygen content in the exhaust system of the vehicle (not shown) and then, compares it with a reference chamber of the lambda sensor 110. The lambda sensor 110 may include a plurality of sensor pins. The difference between the measured oxygen content and a value of reference chamber generates the voltage difference across the plurality of sensor pins. The voltage difference across the plurality of sensor pins is counted as the lambda value. Further, the lambda value is converted into the air-fuel ratio. Based on the feedback of the lambda sensor 110, the at least one processor 115 controls the fuel quantity resulting in the control of the injector pulse width.

The intake throttle valve 111 is a combination of a sensor and an actuator. The intake throttle valve 111 may include a motor and a potentiometer. The potentiometer is electrically connected to the motor. The at least one processor 115 controls the motor through a Pulse Width Modulation (PWM) signal as per the requirement of the control logic and the potentiometer. The PWM signal provides the feedback to the at least one processor 115 associated with an actual position of the intake throttle valve 111. If the actual position is different from a desired position of the intake throttle valve 111, the at least one processor 115 is connected to a proportional–integral–derivative (PID) that may regulate the motor to meet the desired position.

The at least one processor 115 communicates with different modules to control a variety of engine parameters. The different modules include a torque control module 200 (explained in more detail in Figure 2), an air-fuel control module 214 (explained in more detail in Figure 2), a lambda control module 400 (explained in more detail in Figure 4), and an ignition control module 300 (explained in more detail in Figure 3). The torque control module 200 is responsible to achieve the desired torque performance of the engine 114, the air- fuel control module 214 is used to identify and estimate the requirement of air and fuel requirement of the engine 114 to meet the desired performance of the engine 114. The lambda control module 400 is used to control the lambda value in a close loop to maintain a desired lambda required at an engine 114 operating point to achieve the desired performance of the engine 114. The ignition control module 300 is used to produce the spark at a required ignition time to avoid misfire during the combustion of the HCNG fuel inside the engine 114.

The at least one processor 115 is in communication with the air-fuel control module 214 to identify and estimate the requirement of air and fuel for the engine 114 to meet the desired performance of the engine 114 which is explained below.

The present invention discloses the system 100 for controlling the Hydrogen enriched Compressed Gas (HCNG) engine 114 having the at least one processor 115. As mentioned earlier, the at least one processor 115 communicates with the accelerator pedal (not shown) through the accelerator pedal sensor 101, the intake throttle valve 111, the fuel injector 112, and the lambda sensor 110. The at least one processor 115 is configured to determine a default output value of an air supply from the intake throttle valve 111. The default output value of the air supply is based on the torque demand generated by the driver through the accelerator pedal. A look-up table is programmed within the at least one processor 115. A particular amount of the air is supplied from the intake throttle valve 111 as an output to the generated torque demand based on the look-up table. Therefore, for every torque demand generated by the driver, the amount of air supplied from the intake throttle valve 111 is different.

The at least one processor 115 is further configured to compute a corrected output value of the air supply from the intake throttle valve 111 based on a first set of parameters associated with the HCNG engine 114 and one or more ambient conditions. The first set of parameters associated with the HCNG engine 114 includes the intake manifold temperature, the intake manifold pressure, and a volumetric efficiency of the HCNG engine 114. The one or more ambient conditions are indicative of surrounding environmental conditions in which the HCNG engine 114 is operated. The one or more ambient conditions include temperature, pressure, and/or an altitude of the surrounding environment.

The at least one processor 115, based on the corrected output value of the air supply, is then configured to estimate a default value of the fuel injection quantity. The at least one processor 115 internally calculates the fuel injection quantity based on amount of air supplied by the intake throttle valve 111 to maintain the air-fuel ratio.

The at least one processor 115 computes a corrected value of the fuel injection quantity, based on an output from the lambda sensor 110, a second set of parameters associated with the fuel injector 112 and the one or more ambient conditions. The second set of parameters associated with the fuel injector 112 includes the fuel rail temperature, the fuel rail pressure, variations in HCNG gas compositions, and/or variations in voltage of a battery connected to the fuel injector 112.

The at least one processor 115 is then configured to supply air based on the corrected output value and fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine 114 to achieve a final torque equivalent to the torque demand.

In an embodiment, the at least one processor is in communication with the torque control module 200 to achieve the desired torque performance of the engine 114. As explained above, when the torque demand is generated by the driver with help of the accelerator pedal 101, the at least one processor 115 supply air based on the corrected output value and fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine 114 to achieve the final torque equivalent to the torque demand. However, if the final torque is not equivalent to the torque demand, then the final torque is corrected with the help of a torque proportional–integral–derivative (torque PID) to achieve the demanded torque.

In an embodiment, the at least one processor 115 is in communication with the ignition control module 300 to produce the spark at a required ignition time to avoid misfire during the combustion of the HCNG fuel inside the engine 114. The ignition control module is explained below.

The system 100 includes at least one processor 115 adapted to communicate with the accelerator pedal 101, the ignition coil (not shown), a battery (not shown) connected to the ignition coil (not shown), and the spark plug 113. The at least one processor 115 is configured to determine a default output value of a dwell time of the ignition coil based on the torque demand generated through the accelerator pedal (not shown). Further, the at least one processor 115 computes a corrected output value of the dwell time taking account of the variations in voltage supplied by the battery (not shown) to the ignition coil (not shown).

The at least one processor 115, then, determines a default output value of an ignition angle of the spark plug 113, based on the corrected output value of the dwell time and the torque demand. Further, the at least one processor 115 computes a corrected output value of the ignition angle based on a set of primary parameters associated with the HCNG engine 114 and one or more ambient conditions. The set of primary parameters associated with the HCNG engine 114 includes a pressure of a coolant and the coolant temperature.

Lastly, the at least one processor 115 is configured to actuate the spark plug 113 to generate a spark based on the corrected output value of the dwell time and the corrected output value of the ignition angle. The ignition control module 300 is described in detail in Figure 3.

Referring to Figure 2, a schematic view of the system for controlling a supply of air and fuel to the engine 114 using HCNG through the at least one processor 115, according to an embodiment of the present disclosure. The schematic view of the system further illustrates the torque control module 200 and the air-fuel control module 214 which is used to identify and estimate the requirement of air and fuel for combustion in the engine 114 to meet the desired torque performance of the engine 114.

The torque control module 200 and air-fuel control module 214 define the method to identify and estimate the requirement of air and fuel for combustion in the engine 114 to meet the desired torque performance of the engine 114 is elaborated and the steps are as follows. The steps 201-208 and 211-213 are part of the air-fuel control module 214. The steps 201-213 are part of torque control module 200. Hence, the air-fuel control module 214 is a sub-module in the torque control module 200.

Between steps 201-203, the default output value of the air supply from the intake throttle valve 111 based on the torque demand generated through the accelerator pedal is determined by the at least one processor 115. At step 201, the driver of the vehicle (not shown) generates the torque demand by pressing the accelerator pedal (not shown). At step 202, an input signal is generated by the accelerator pedal sensor 101 and communicated to the at least one processor 115 to determine the amount of torque desired by the driver based on the position of the accelerator pedal (not shown). The position of the accelerator pedal is communicated to the at least one processor 115 by the accelerator pedal sensor 101. At step 203, the at least one processor 115 actuates the intake throttle valve 111 to provide an air supply. The air supplied through the actuation of the intake throttle valve 111 is based on the look-up table programmed inside the at least one processor 115 where the torque demand generated is proportional to the default value of air output to maintain the air-fuel ratio equals 17.7:1. Therefore, the opening of the intake throttle valve 111 is based on the torque demand generated by the driver.

Between steps 204-206, the at least one processor 115 computes a corrected output value of the air supply from the intake throttle valve 111 based on the first set of parameters associated with the HCNG engine 114 and the one or more ambient conditions. At step 204, the T-MAP sensor determines the pressure and temperature of an intake manifold. The input from the T-MAP sensor 104 is communicated to the at least one processor 115. At step 205, the at least one processor 115, checks the intake manifold pressure, the intake manifold temperature, the volumetric efficiency of the engine 114, and the first set of parameters associated with the HCNG engine 114 and the one or more ambient conditions, corrects the default value of the air supply by actuating the intake throttle valve 111. Ideally, the volumetric efficiency of the engine 114 should be 100 percent theoretically. However, practically there are some system-generated losses due to which the volumetric efficiency of the engine is not 100 percent. Hence, the at least one processor 115 compensates for the losses and adjusts the air supply from the intake throttle valve 111. At step 206, the corrected output value of air supply is provided by the at least one processor 115 to the engine 114.

Now, the air-fuel ratio of the HCNG engine 114 is 17.7:1 which means that to burn 17.7 kg of air, 1 kg of HCNG is required. Hence, based on the corrected output value of the air supply, the fuel injection quantity is estimated to maintain the air-fuel ratio. Hence, at step 211, the at least one processor 115 estimates the default value of the fuel injection quantity based on the corrected output value of the air supply.

At step 212, the at least one processor 115 computes the corrected value of the fuel injection quantity based on the output from the lambda sensor 110, the second set of parameters associated with the fuel injector 112, and the one or more ambient conditions. The fuel rail is used to supply HCNG at a required pressure from the high-pressure HCNG regulator to the fuel injector 112. The HCNG temperature and pressure inside the fuel rail are monitored by the rail pressure and temperature (RPT) sensor 105. The input from the RPT sensor 105 is sent to the at least one processor 115 to compute the corrected value of the fuel injection quantity for combustion. Also, the HCNG storage tank temperature and pressure may also vary. One example is when the HCNG gas expands, it generates a cooling effect, hence, there may be a drop in temperature inside the HCNG storage tank. The temperature and pressure of the HCNG storage tank are gauged by the HCNG tank pressure and temperature sensor 109 which then communicates with the at least one processor 115 regarding the variations in the pressure and the temperature of the HCNG storage tank and accordingly, the least one processor 115 to compute the corrected value of the fuel injection quantity for combustion.

At step 213, based on the corrected value of the fuel injection quantity, the injector pulse width is determined by the at least one processor 115.

At step 207, the at least one processor 115 supplies the air based on the corrected output value and the fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine 114 to achieve the final torque equivalent to the torque demand. The at least one processor 115 controls the injector pulse width to supply the fuel from the fuel injector 112 based on the lambda value provided by the lambda sensor 210.

At step 208, the final torque is achieved from the combustion of the air based on the corrected output value and the fuel based on the corrected value of the fuel injection quantity. At step 209, the torque generated after the air-fuel combustion inside the engine 114 is further corrected through the torque proportional–integral–derivative (torque PID). The correction is required to prevent friction losses. Furthermore, a corrected value of the final torque equivalent to the torque demand is thereby generated at step 210.

The air-fuel control module 214 includes a feed-forward mechanism and a feedback mechanism. The feed-forward mechanism is provided to prevent any delay in the supply of fuel and air to the engine for combustion. However, the feedback mechanism is provided for the corrected value of the fuel and the air in the engine 114 after taking into consideration of the first set of parameters, the second set of parameters, the one or more ambient conditions to meet the desired torque demand and the air-fuel ratio.

In the air-fuel model 214, the lambda sensor 110 aids in the correction of the fuel only for optimum combustion and minimum emission and not the air, per se. In other words, to reach a desired lambda value, the at least one processor 115 controls the injector pulse width by actuating the fuel injector 112 to reach the desired lambda value based on the corrected output value of the air supply and input from the lambda sensor 110.

Referring to Figure 3, illustrates a schematic view of the system 100 for controlling the ignition timing of the engine 114 using HCNG through at least one processor 115, according to an embodiment of the present disclosure.

When an electric current is applied to the primary winding of an ignition coil (not shown), it will take a short time for the current flow to reach its maximum amperage. The strength of the magnetic field (or magnetic flux) created around the winding is directly proportional to the current flow. It will take the same amount of time for the magnetic field to reach its maximum strength. When the current flow and magnetic field are at their maximum, the magnetic field will then be stable.

The time taken to build the magnetic field to maximum strength is often referred to as ‘charge-up’ time for the ignition coil (not shown). The period when the system 100 applies an electric current to the ignition coil’s primary winding (not shown) is often referred to as “dwell period” or “dwell time”. The dwell time is controlled electronically so there is always sufficient time to fully charge the ignition coil (not shown). However, at higher engine speeds, the reduced dwell time prevented the magnetic field from reaching full strength because of two potential issues: a) If the electric current is not applied to the primary winding for long enough, the magnetic field will not reach its maximum strength; b) If the current is applied for too long, it could cause overheating of the electrical circuits and the primary winding. For proper sparking, the optimum dwell time based on the speed of the engine 115 and the torque demand generated by the driver is required.

At step 301, the default output value of the dwell time of the ignition coil based on the torque demand generated through the accelerator pedal (not shown) and the speed of the engine 114 is determined by the at least one processor 115. At step 302, the at least one processor 115 computes the corrected output value of the dwell time based on the voltage supplied by the battery to the ignition coil (not shown). The present disclosure applies a different ignition angle for every torque demand generated by the driver and the look-up table is pre-programed inside the at least one processor 115 to retrieve a specific value of the ignition angle for a specific amount of the torque demanded by the driver. Therefore, at step 303, the at least one processor 115 determines the default output value of the ignition angle of the spark plug 113 based on the corrected output value of the dwell time and the torque demanded by the driver.
At step 304, the at least one processor 115 compute the corrected output value of the ignition angle based on the set of primary parameters associated with the HCNG engine 114 and the one or more ambient conditions. The set of primary parameters associated with the HCNG engine includes the coolant pressure and the coolant temperature of the coolant. The one or more ambient conditions are indicative of the surrounding environmental conditions in which the HCNG engine is operated. The one or more ambient conditions includes temperature, pressure, and altitude of the surrounding environment. The correction of the ignition angle is necessary because if the sparking gets delayed, the combustion will not occur.
Lastly, the at least one processor 115 actuates the spark plug 113 to generate the spark based on the corrected output value of the dwell time and the corrected output value of the ignition angle to achieve best fuel economy and low emissions (step 305).

The ignition control module 214 includes a feed-forward mechanism and a feedback mechanism. The feed-forward mechanism is provided to prevent any delay in sparking caused by the spark plug 113. The feedback mechanism is provided for the corrected value of the parameters required for generating a proper spark by the spark plug thereby preventing the misfiring of the spark plug 113.

Referring to Figure 4, illustrates a flow chart for the lambda control module 400 to control the lambda value in the close loop to maintain the desired lambda value required at the engine 114 operating point to achieve the desired performance of the engine 114. The working of the system is explained below:

At step 401, the lambda sensor 110 is in communication with the at least one processor 115 for monitoring the actual air-fuel ratio of the system 100. The present disclosure uses a wide band lambda sensor 110. The main benefit of using the wide band lambda sensor 110 in comparison to a narrow band (switching type) lambda sensor 110 is that the system 100 can identify the actual air-fuel ratio and correct the fueling in next cycle without going to correct in steps as in case of the switching type lambda sensor. This will provide the benefit of a faster control response of the at least one processor 115 as compared to the switching type lambda sensor 110. This will increase the accuracy of the system 100 to control the fueling requirement of the engine 114.

At step 402, the lambda value is obtained as input from the lambda sensor 110 by the at least one processor 115. At step 403, the lambda value is checked by the at least one processor 115, to be within a predetermined threshold range. The at least one processor 115 identifies the engine speed and the load of the engine 114 with the help of the crank position sensor 102 and the T-MAP sensor 104. The look-up table for the lambda value was set to achieve the desired lambda value which is within the predetermined threshold range. The at least one processor 115 will look up for a desired value for the speed, and then, calculates the fuel requirement of engine 114 to reach the desired lambda. At step 404, if the lambda value obtained from the lambda sensor 110 is not within the predetermined threshold range, the at least one processor 115 adjusts the injector pulse width of the at least one injector of the fuel injector 112 to achieve the desired lambda value. The lambda sensor 110 provides feedback to the at least one processor 115. Further, the at least one processor 115 corrects the injector pulse width to maintain the lambda value until the desired lambda value is achieved by the system 100.

With the help of the close loop lambda control module 400, the at least one processor 115 controls the injector pulse width to meet the desired torque and the desired lambda value and controls the excess oxygen in the system 100. The at least one processor 115 read the lambda value from the lambda sensor 110 and controls the injector pulse width, if the lambda value is not in the predetermined threshold range of calibration. At step 405 and 406, along with the lambda monitoring, the at least one processor 115 calculates the torque of the system 100 and try to match the torque achieved by the system 100 with the torque demanded by the driver, by adjusting the air supply to engine 114 by controlling the intake throttle valve 111. At 407, the at least one processor 115 can control the excess air or oxygen available in the system to maintain the torque of the engine 114 by controlling the intake throttle valve 111 and the at least one processor 115 can control the injector pulse width of the fuel injector 112 to reach the desired lambda value. At 408, the cycle continues till the time desired lambda value and torque are achieved.

Referring to Figure 5 illustrates a flow chart of the strategy to switch the lambda value based on coolant temperature through the at least one processor, according to an embodiment of the present disclosure.

The lambda sensor 110 is a critical component in modern automotive engines that measures the amount of oxygen in the exhaust gases. The at least one processor 115 uses a data from the lambda sensor 110 to adjust the air-to-fuel ratio in the engine 114 to ensure optimal combustion and reduce emissions.

The coolant temperature of the engine 114 can affect the performance of lambda sensor 110 because it determines the operating temperature of the engine 114. If the engine 114 is too cold, the lambda sensor 114 may not produce accurate readings, leading to incorrect air-to-fuel ratios and reduced engine performance. On the other hand, if the engine 114 is too hot, the lambda sensor 110 may also produce inaccurate readings, leading to potential damage to a catalytic converter (not shown).

Therefore, the at least one processor 115 monitors the coolant pressure sensor 106 and the coolant temperature sensor 107, and adjusts the performance of lambda sensor 110 accordingly. The at least one processor 115 may delay the readings of lambda sensor 110 until the engine 114 reaches the proper operating temperature or may adjust the air-to-fuel ratio to compensate for the cold or hot engine temperature.

At step 502, the coolant temperature can affect the air-to-fuel ratio in the engine 114 in several ways, which can lead to either a lean air-fuel mixture or a rich air-fuel mixture. The at least one processor 115 checks if the coolant temperature is within a threshold range. At step 503, if the coolant temperature is within the threshold range, the at least one processor 114 checks if the engine 114 is cold or hot.

At step 503, when the engine 114 is cold, the fuel in a combustion chamber (not shown) may not vaporize completely, leading to incomplete combustion and the production of hydrocarbons and carbon monoxide. To compensate for this, the at least one processor 114 may enrich the air-fuel mixture, meaning adding more fuel to the mixture to ensure complete combustion. This results in the rich air-fuel mixture, with a higher ratio of the fuel to the air.

At step 503, when the engine warms up, the fuel vaporization improves, and the at least one processor 115 can reduce the amount of fuel added to the mixture, resulting in the leaner air-fuel mixture with a lower ratio of the fuel to the air. The lambda sensor 110 measures the amount of oxygen in the exhaust gases and sends a signal to the at least one processor 115, which adjusts the air-fuel mixture accordingly.

At step 504, if the coolant temperature is greater than the threshold range, it can lead to pre-ignition, where the air-fuel mixture ignites before the spark plug 113 fires, leading to the failure of engine 114. To prevent this, the at least one processor 115 may cut off the system 100 till the coolant temperature falls within the threshold range thereby preventing any failure to the system 100.

Referring to Figure 6 illustrates a graphical representation of the switching of lambda value based on the coolant temperature for improving NOx conversion through the at least one processor, according to an embodiment of the present disclosure.

As shown in the graph, to achieve better NOx reduction in the system 100, the at least one processor 115 switches the target lambda point at a defined frequency to a lean side or a rich side to achieve a higher fuel economy based upon the coolant temperature of the engine 114. This helps to increase the NOx conversion efficiency in a three-way catalytic converter (not shown) without affecting the fuel economy and performance of the engine 114.

Further, the use of Lean Lambda sensor strategy on the at least one processor 115 gives the accessibility to a user to go to a very leaner lambda value on the engine 114 without compromising the performance and emission of the engine 114. This strategy will give the benefit fuel economy and achieve a lower Brake specific fuel consumption (BSFC) of the engine 114. The at least one processor 115 identifies a desired lambda operating point from the look-up table for the lambda value based on an engine operating point and controls the injected quantity of the fuel by controlling the injection timing to achieve the desired lambda operating point.

Further, the three-way catalytic converter (not shown) may also be used as an alternative to the lambda control module. In the system 100, a three-way catalytic converter can be adapted to control the exhaust emission of the engine 114. The following chemical reactions take place inside the three-way catalytic converter (not shown) for controlling the exhaust emission.

• 2 NO + 2 CO ? N2 + 2 CO2
• 2 CO + O2 ? 2 CO2
• CH4 + 2 O2 ? CO2 + 2 H2O

In above chemical reactions, carbon monoxide (CO) and the hydrocarbon are oxidized and further converted into carbon dioxide (CO2) and water (H2O) while NOx is reduced into Nitrogen (N2) and carbon dioxide (CO2). When the air-fuel mixture is taken to leaner side to achieve better fuel efficiency, oxygen content will increase in the exhaust system of the engine 114. Thus, the hydrocarbon and CO emissions are reduced, it will increase the NOx content in the exhaust system and decrease the efficiency of NOx conversion in catalytic convertor because of higher availability of oxygen content.

The usage of HCNG as a fuel improves performance, reduces the emissions, and decreases the fuel consumption of the existing engines. The systems and the methods optimize various engine operating and design parameters using at least one processor 115 for a use of HCNG as a fuel. The at least one processor 115 is designed and manufactured for HCNG fuel operation in light commercial and/or heavy-duty applications. The at least one processor 115 ensures the right metering of HCNG fuel into the engine by maintaining the optimal air-fuel ratio and ignition timing. The at least one processor 115 determines the real-time value of the fuel injection and ignition timing taking into account variations in the system and the ambient conditions.

Further, the system and method having at least one processor 115 is successfully tested in a commercial vehicle engine for efficacy in terms of reducing emissions as well as increasing fuel economy without compromising the performance.

Experimental Data

Extensive experiments were conducted on the at least one processor of the system after development along with a heavy-duty engine. A transient engine test bench was used for conducting experiments. HCNG fuel produced from a compact reformer unit was used in the experimentation process. Firstly, the baseline emission data with CNG fuel was generated. Secondly, multiple iterations were performed in the at least one processor for optimizing the desired parameters in order to meet BS VI emission values as well as better fuel economy with HCNG fuel. The three-way catalyst was also used in the experimentation process of the system.

Referring to Figure 7, which illustrates the details of emission data of carbon monoxide, methane, non-methane hydrocarbon and oxides of nitrogen, recorded over the tests are depicted in Figures 7(a), 7(b), 7(c) and 7(d) respectively. Figure 7(a) illustrates details of the emission data of carbon monoxide, and Figure 7(b) illustrates details of the emission data of methane. Further, Figure 7(c) illustrates details of emission data of non-methane hydrocarbon, and Figure 7(d) illustrates details of emission data of oxides of nitrogen. Moreover, Figure 7(e) illustrates specific fuel consumption data recorded over World Harmonized Transient Cycle (WHTC) tests. During the multiple iterations, the air-fuel ratio and spark timing were altered to obtain lower emissions and lower fuel consumption.

Table 1 provides the BS-VI emission limits for natural gas based on heavy-duty cycles where the engines are tested on a transient engine test bed following the World Harmonized Transient Cycle (WHTC).

Table 1
LIMITS CO
(mg/kWh) NOx (mg/kWh) CH4
(mg/kWh) NMHC (mg/kWh)
BS - VI 4000 460 500 160

Table 2 provides a comparison of emission and specific fuel consumption (SFC) data of the engine with HCNG fuel and the at least one processor of the present disclosure, compared to base line CNG operation. It can be noted that the SFC of the engine with HCNG fuel and the at least one processor of the present disclosure, was lowered by 10.7% compared to baseline CNG fuel.
Table 2
Test Details CO
(mg/kWh) NOx (mg/kWh) CH4 (mg/kWh) NMHC (mg/kWh) SFC
(g/kWh)
BS VI engine with CNG fuel (baseline) 2610 190 300 20 369.60
BS VI engine with HCNG fuel and the engine controller 350 390 294 130 330.10

The present disclosure provides the system and the method for optimizing the desired engine parameters for using HCNG as fuel without making modifications to the existing engines. The system and the method of controlling engine parameters to use HCNG as a fuel improve performance, and fuel economy and reduce emissions of the engine. Further, the system and the method are adapted to optimize the air-fuel ratio for improved engine performance and after-treatment performance. Another advantage associated with the present disclosure is optimization of the spark timing for improved engine performance and decreased oxides of nitrogen emissions. Moreover, the system of the present disclosure is flexible to operate on both high-power condition and lower emission condition without compromising fuel economy. ,CLAIMS:1. A system (100) for controlling a Hydrogen enriched Compressed Gas (HCNG) engine (114) comprising:
at least one processor (115) adapted to communicate with at least one of an accelerator pedal, an intake throttle valve (111), a fuel injector (112), and a lambda sensor (110), wherein the at least one processor (115) is configured to:
determine a default output value of an air supply from the intake throttle valve (111) based on a torque demand generated through the accelerator pedal;
compute a corrected output value of the air supply from the intake throttle valve (111) based on a first set of parameters associated with the HCNG engine and one or more ambient conditions;
estimate a default value of a fuel injection quantity based on the corrected output value of the air supply;
compute a corrected value of the fuel injection quantity based on an output from the lambda sensor (110), a second set of parameters associated with the fuel injector (112), and the one or more ambient conditions; and
supply air based on the corrected output value and fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine (114) to achieve a final torque equivalent to the torque demand.

2. The system (100) as claimed in claim 1, wherein to supply the air and the fuel, the at least one processor (115) is further configured to:
control one of an opening and a closing of the intake throttle valve (111) to supply the air based on the corrected output value of the air supply; and
control an injector pulse width of the fuel injector (112) to supply the fuel based on the corrected value of the fuel injection quantity.

3. The system (100) as claimed in claim 1, wherein the first set of parameters associated with the HCNG engine (114) comprises at least one of a temperature of an intake manifold, a pressure of the intake manifold, and volumetric efficiency of the HCNG engine (115).

4. The system (100) as claimed in claim 1, wherein the second set of parameters associated with the fuel injector (112) comprises at least one of a temperature of a fuel rail, a pressure of the fuel rail, variation in HCNG gas compositions, and variation in battery voltage.

5. The system (100) as claimed in claim 1, wherein the one or more ambient conditions are indicative of surrounding environmental conditions in which the HCNG engine (114) is operated, wherein the one or more ambient conditions comprises at least one of a temperature, a pressure, and an altitude.

6. The system (100) as claimed in claim 1, wherein a deviation in the final torque with respect to the torque demand is corrected through a Proportional–Integral–Derivative (PID) controller.

7. A system (100) for controlling a Hydrogen enriched Compressed Gas (HCNG) engine comprising:
at least one processor (115) adapted to communicate with at least one of an accelerator pedal, an ignition coil, a battery, and a spark plug (113), wherein the at least one processor (115) is configured to:
determine a default output value of a dwell time of the ignition coil based on a torque demand generated through the accelerator pedal;
compute a corrected output value of the dwell time based on a voltage supplied by the battery to the ignition coil;
determine a default output value of an ignition angle of the spark plug (113) based on the corrected output value of the dwell time and the torque demand;
compute a corrected output value of the ignition angle based on a set of primary parameters associated with the HCNG engine (114) and one or more ambient conditions; and
actuate the spark plug (113) to generate a spark based on the corrected output value of the dwell time and the corrected output value of the ignition angle.

8. The system (100) as claimed in claim 7, wherein the set of primary parameters associated with the HCNG engine (114) comprises at least one of a pressure of a coolant and a temperature of the coolant.

9. The system (100) as claimed in claim 7, wherein the one or more ambient conditions are indicative of surrounding environmental conditions in which the HCNG engine (114) is operated, wherein the one or more ambient conditions comprises at least one of a temperature, a pressure, and an altitude.

10. A method (200) for controlling a Hydrogen enriched Compressed Gas (HCNG) engine (114) by at least one processor (115) comprising the steps of:
determining a default output value of an air supply from an intake throttle valve based on a torque demand generated through an accelerator pedal (steps 201-203);
computing a corrected output value of the air supply from the intake throttle valve based on a first set of parameters associated with the HCNG engine and one or more ambient conditions (steps 204-206);
estimating a default value of a fuel injection quantity based on the corrected output value of the air supply (step 211);
computing a corrected value of the fuel injection quantity based on an output from the lambda sensor, a second set of parameters associated with the fuel injector and the one or more ambient conditions (steps 212-213); and
supplying air based on the corrected output value and fuel based on the corrected value of the fuel injection quantity for combustion to the HCNG engine to achieve a final torque equivalent to the torque demand (steps 206-210).

11. The method (200) as claimed in claim 10, wherein the supplying of the air and the fuel to the HCNG engine (114) by the at least one processor (115) further comprising the steps of:
controlling one of an opening and a closing of the intake throttle valve (111) to supply the air based on the corrected output value of the air supply (steps 203-206); and
controlling an injector pulse width of the fuel injector (112) to supply the fuel based on the corrected value of the fuel injection quantity (steps 212-213).

12. The method (200) as claimed in claim 10, wherein the first set of parameters associated with the HCNG engine (110) comprises at least one of a temperature of an intake manifold, a pressure of the intake manifold, and volumetric efficiency of the HCNG engine.

13. The method (200) as claimed in claim 10, wherein the second set of parameters associated with the fuel injector comprises at least one of a temperature of a fuel, a pressure of the fuel rail, variation in HCNG gas compositions, and variation in battery voltage.

14. The method (200) as claimed in claim 10, wherein the one or more ambient conditions are indicative of surrounding environmental conditions in which the HCNG engine (114) is operated, wherein the one or more ambient conditions comprises at least one of a temperature, a pressure, and an altitude.

15. The method (200) as claimed in claim 10, wherein a deviation in the final torque with respect to the torque demand is corrected through a Proportional–Integral–Derivative (PID) controller.

16. A method (300) for controlling a Hydrogen enriched Compressed Gas (HCNG) engine (114) by at least one processor (115) comprising the steps of:
determining a default output value of a dwell time of an ignition coil based on a torque demand generated through an accelerator pedal (step 301);
computing a corrected output value of the dwell time based on a voltage supplied by a battery to the ignition coil (step 302);
determining a default output value of an ignition angle of a spark plug based on the corrected output value of the dwell time and the torque demand (step 303);
computing a corrected output value of the ignition angle based on a set of primary parameters associated with the HCNG engine and one or more ambient conditions (step 304); and
actuating the spark plug to generate a spark based on the corrected output value of the dwell time and the corrected output value of the ignition angle (step 305).

17. The method (300) as claimed in claim 16, wherein the set of primary parameters associated with the HCNG engine (114) comprises at least one of a pressure of a coolant and a temperature of the coolant.

18. The method (300) as claimed in claim 16, wherein the one or more ambient conditions are indicative of surrounding environmental conditions in which the HCNG engine (114) is operated, wherein the one or more ambient conditions comprises at least one of a temperature, a pressure, and an altitude.