FIELD OF INVENTION
The invention is related to automotive testing system. More particularly testing of electrified vehicles in test laboratories by using all kinds of dynamometer and testing stands.
BACKGROUND OF THE INVENTION
In twenty first centuries the vehicles have become culturally integral and indispensable to the modern economy. Unfortunately, fossil fuels are used to power such vehicles which having manifold drawbacks, including but not limited to a dependence on limited foreign sources of oil and natural gas. These foreign sources are often found in volatile geographic locations which are most egregious. The production process and by-products of fossil fuels produces pollution which is one of the reasons of climate change. There are number of ways for the solution but one of the ways to address these problems is to increase the fuel economy of hydrocarbon fuel powered vehicles. However, gasoline powered vehicles do not eliminate the need for fossil fuels, as they still require combustible composition to run internal combustion engine therefore there is need of clean fuel.
Accordingly, there is a more popular approach has been to use which is cleaner technologies, such as electric motors powered by fuel cells or batteries. However, many of these clean technologies are not yet practical and having more drawbacks. For example, fuel cell vehicles are still under development and these are expensive. Hydrogen powered fuel cells first require the chemical extraction (via electrolysis) of diatomic hydrogen (H2) and transportation thereof inside a vehicle, which is inherently dangerous.
The consequences of climate change are being experienced across the globe at an unprecedented level. It is driving the strong push towards electrification & hybridization of power train in order to make exhaust emission cleaner & because of which, vehicle manufacturers face tougher development challenges as tailpipe emissions from the Internal Combustion Engines are subject to higher levels of scrutiny and stricter legislation. These emissions contribute to poor air quality metrics, especially in urban areas, where the pollutants NOx and particulate matters pose the most serious harm to human health.
Many countries that host large numbers of automobiles have exhaust gas emissions or vehicle efficiency standards that automobile manufacturers must comply with the standard requirements. But experience has shown that it is difficult and expensive to test vehicles under the broad range of real-world environment like different road conditions to different driving conditions that are known to affect emissions, fuel economy, or the energy efficiency of vehicles in the real world. And it is well known that the energy efficiency of Hybrid electric Vehicles (HEVs) and the mileage range of Battery Electric Vehicles (BEVs) on a single charge decrease at lower ambient temperatures.
Also, considering the global warming due to green gaseous emissions and increasing level of pollution, technical experts with close association with government authority bodies in many countries are moving towards electrification of the mobility. There are different challenges in case of electrified vehicles with respect to complex system architecture, thermal management challenges and range anxieties which are major focus areas to develop robust electrified vehicles. Major challenges for automotive manufacturers are to reduce development and validation time and efforts without compromising on the quality and robustness of the end-product before launching into the market.
The greatest impediment to electric vehicles (EV’s), particularly to extended range of electric vehicles has been less as compared to gasoline powered vehicles and this range remains low because of the outdated battery technology. In recent days the existing battery technology has experienced a fraction of recent progression. However, batteries contribute approximately 40% to the cost of a new vehicle. Rechargeable battery technology has simply not advanced to the point where mass-produced and cost-effective batteries can power electric vehicles for long distances. Therefore there is need to understand the exact performance and working principle of the vehicles at different or extreme conditions of the environmental conditions. As results , there is high importance is given by the automobile manufacturers for road to test rigs vehicle testing so that the vehicle testing provide accurate and perfect results so that automobile manufacturers can use this results to improve their product at its their best level.
Considering the future emission legislation requirements for Internal Combustion Engines (ICE) and Electrified vehicles, OEM’s need spent huge development efforts to validate for performance and emissions on their vehicles on roads for emission pollutants control and addressing the range/safety concerns for ICE and Electrified vehicles respectively. Road to Rig methodologies are already available in the market from many engineering consultancy providers as a front-loading approach to reduce overall vehicle program time and efforts. There were several approaches available in the market to simulate on road cycles into the laboratories to enhance rapid development of power trains with lower development cost and efforts. But every approach and methodology have its own advantages and disadvantages with respect to accuracy of correlation which is an important factor for manufacturers to develop vehicles within the laboratory.
While laboratory testing methods are known to be very accurate and repeatable for emissions and efficiency measurements under actual test conditions, real-world driving can subject a vehicle to a wide range of conditions that traditional laboratory testing protocols would not. There are many reasons for this, including the difficulty of simulating the full range of real-world temperature and atmospheric pressure conditions in the laboratory, the effects of real-world driver behaviour under actual traffic conditions, etc.
It is not currently possible to perform a “blind test” for hybrid and electric vehicles in a laboratory environment for measuring exhaust emissions, fuel economy, or vehicle efficiency. There are number of factors are needs to be considered which affects emissions and energy efficiencies in most vehicles, especially if the vehicle power trains evolve to employ different calibrations compared with the standard calibrations that would be employed for a similar real-world drive under conventional driver control.
With the depth of technical knowledge possessed by the developers of the vehicles and automotive testing system, it may be possible to isolate and simulate the effects that other. However, in real-world condition on the electrical or hybrid vehicle control systems to obtain some degree of confidence regarding the operation of the system in the real world, but that type of testing does not demonstrate the complete vehicle system behaviour the same way in the real world. A complete vehicle system test would offer the highest level of confidence that laboratory results accurately and adequately reflect real-world performance and would be appropriate and suitable for regulators who do not have regular access to detailed technical information regarding a specific make and model of vehicle. In real working conditions of vehicle emissions, efficiency, and fuel economy characteristics of a vehicle may be degraded with respected to automated longitudinal controller of vehicle means there is performance difference between a new vehicle and used vehicle of same specifications. Therefore, it is also possible to employ such systems for validation of vehicle performance for the improvement in working of that product.
Traditional laboratory testing for emissions or energy efficiency compliance purposes usually includes measuring exhaust emissions or energy efficiency of the subject vehicle operating on one or more vehicle speed schedules on a dynamometer. Various vehicle speed schedules are intended to represent various types of real-world vehicle operations. For example, the Environmental Protection Agency (EPA) employs different speed schedules for representing city operation, highway operation, and more aggressive vehicle operation. In each case, the vehicle is operated as closely as possible to the corresponding speed schedule by a driver. But in hybrid vehicles there is combination of Internal Combustion Engine and battery pack and in electrified vehicle only electric battery is used as a source of energy therefore every factor of the vehicle performance needs to considered. If it is ignored or neglected it may affect the entire test results. On the other hand as a convenience feature in these vehicles acceleration and deceleration phase only occurs without the interference of separate transmission system. Because these features are truly convenient for these vehicles for maintaining safe vehicle separation under any operating condition, ranging from bumper-to-bumper city traffic to highway operation, and because the cost of the technology is falling rapidly, these features are likely to be found, and used, on most vehicles in the future. And they are likely to continue to be one of the key technologies of fully electric vehicles of the future. To accomplish these goals however, a well-controlled, laboratory-based testing apparatus and associated methods are needed to maximize testing precision and representativeness for both automobile manufacturers and regulators.
The prior art reveals that there have been attempts to develop a system for testing vehicles on dynamometer to determine the various necessary vehicle parameters according to need of user. Following patent literature describes the existing state of the art.
JP2007139527A discloses a dynamometer for electric car wherein dynamometer for an electric car directly couples an electric car motor and a dynamometer which generates a torque instruction for the motor from a motor controller to drive the motor by an electric car inverter and generates a torque instruction for the dynamometer from a dynamo controller to drive the dynamometer by a dynamo inverter. When the motor is in decelerating controlled, a motor brake amount calculation section regenerative controls the electric car inverter with limited in a torque range of a limiter value of regenerative driving set in the motor. Torque which cannot be regenerated by the motor is added to the torque instruction of the dynamo inverter by a dynamo break amount calculation section and a control section , thereby achieving deceleration and stop control by the dynamometer. In this invention there are no on road trials conducted and there is no any prediction for resistive loads which needs to be applied so it become complex task in wheel torque measurements performance. This is a major flaws in this invention.
EP3214422A1 discloses an electrical vehicle testing device and method. In this testing method a motor is driven at the load of rotation speed and torque equivalent to the running of an electric vehicle by using a test device directly connected to a motor and a dynamometer and outputting from the dynamometer side torque corresponding to the running resistance according to the speed. As another testing method, there is a method for verifying a motor and an ECU by controlling the motor using the actual motor control ECU. In this disclosed method control unit calculates running resistance based on accelerator and brake signal and actual rotational speed of test motor achieved which is not enough to determine the vehicle performance.
JPH08334439A discloses chassis dynamometer for electric automobile which is constituted of a chassis dynamometer composed of two rollers and dynamometers a temperature adjuster and two battery simulators to secure resolution of load control, realize larger real inertia, and secure space efficiency. The dynamometers simulate the corresponding total running resistances and inertia drive shafts of the vehicle in a case except braking, however, in the case of decelerating and braking, respective dynamometers simulate the running resistances and the inertias of respective shafts so that respective speeds are controlled to be equalized each other. Therefore, the brake of a non-driving wheel is equally acted as the one in the real running so that the brake of the vehicle including regenerative braking can be faithfully simulated.
US6021365A discloses method of testing regenerative braking force in electric vehicle. In this invention the braking force of the driven wheels is detected by the two-axle chassis dynamometer; and assuming that the detected braking force is a total braking force of the driven wheels and follower wheels, the reference regenerative braking force produced by the driven wheels is calculated on the basis of the data obtained by determining the braking force distribution to the driving and follower wheels in advance, as a function of force applied to the brake pedal. Based on the actual pedal depressing force and the data, an imaginary pedal depressing force is calculated that is required to produce a total braking force of the driven wheels and follower wheels equal to the braking force generated by the driven wheels in the actual pedal depressing force. Based on the imaginary pedal depressing force and the data, an imaginary regenerative braking force that is produced by the driven wheels in the imaginary pedal depressing force is calculated and then compared with the reference regenerative braking force. In this way the regenerative braking force test is conducted. This invention is only restricted towards laboratory level activity. In this invention road test of vehicle is completely neglected due to which Load profiles of vehicle components that are determined and analysed on the basis of actual street load data the service life of the vehicle may improve and it becomes for understanding of the effect of driving behaviour and road conditions on the stress on components or on the entire vehicle.
US6457351B1 discloses hybrid electric vehicle testing method and system. In this invention a hybrid electric vehicle is placed in a running condition on a chassis dynamometer, a vehicle-end data is acquired by access to sensors in the vehicle. In this invention dynamometer end data is acquired by measurements at the chassis dynamometer, and the vehicle-end data and the dynamometer-end data are analysed for inspections of drive and control systems of the vehicle. In this invention the described method provides the comparison of vehicle sensor data to chassis dynamometer result data and it's analysis for drive and control systems. In this invention acceleration phase is kept at for constant speed which is not the suitable condition of vehicle testing due to which the disclosed methods fails to provide accurate results which is nothing but the essential factor of any vehicle testing system.
For the reasons stated above, which will become apparent to those skilled in the art upon reading and understanding the challenges in , there is a need in the art for a system for testing vehicles. The present invention has been made in consideration of the above-described problems of the prior art, and it is an object of the present invention to provide system for accurate replication and emulation of performance, emissions, range, and recuperation energy levels on electrified vehicles from on road to test laboratories for all kind of dynamometers and testing stands .
Henceforth, for solving the abovementioned problems, the system is developed for performing tests of the complex drive system and control system of such a fuel powered vehicles or hybrid or electrified vehicles.
The present inventions delivering more value added benefits to many automobile manufacturers for development of electrified vehicles (Hybrid, BEV and FCEV), overcome obstacles in replicating all real-world driving cycles in the laboratories on all kinds of dynamometers and testing stands. This enables for many OEMs to reduce their product life cycle with minimum efforts and time.
OBJECT OF THE INVENTION
The object of the present invention is to provide a system and method for testing a fuel powered and hybrid or electrified vehicle wherein a variety of tests are performed on road test and after that on a drive system with a control system of the vehicle while it is in a simulated running condition.
Another object of the invention is to provide system and method for testing a fuel powered and hybrid or electrified vehicle which runs under integrated control of an engine or an electric motor or in combination of both which is run on a road which includes drive and control systems for the testing various parameters by method vehicle running on a stationary running system and acquiring data from the running vehicle by access to the sensors and analyzing the obtained data with on road data to inspect the drive and various control systems of vehicle
Yet another object of the invention is to provide system and method for testing a fuel powered and hybrid or electrified vehicle to achieve accurate replication and emulation to determine the performance, emissions, range, and recuperation energy levels on electrified vehicles from on road to test laboratories
Yet another object of the invention is to provide system and method for testing a fuel powered and hybrid or electrified vehicle to deliver more value to many automobile manufacturers for development of electrified vehicles (Hybrid, BEV and FCEV) and to overcome the obstacles in replicating all real-world driving cycles in the laboratories.
Yet another object of the invention is to provide system and method for testing a fuel powered and hybrid or electrified vehicle which enables for many OEMs to reduce their product development life cycle with minimum efforts and time.
Yet another object of the present invention is to provide a system and method for testing a fuel powered and hybrid or electrified vehicle to optimize maintenance and reliability of various components and eventually reduce the cost by providing testing with exact replication, emulation and simulation of road testing or customisable testing according to need of user in test laboratories
Yet another object of the present invention is to provide a system and method for testing a fuel powered and hybrid or electrified vehicle to increase the overall efficiency of the testing and to reduce the errors by providing testing with exact replication and simulation of road testing.
Yet another object of the present invention is to provide a system and method for testing a fuel powered and hybrid or electrified vehicle to maximize various testing facilities under a single vehicle testing.
Yet another object of the present invention is to provide a system and method for testing a fuel powered and hybrid or electrified vehicle that is inexpensive, robust, and simple in operation and control.
SUMMARY OF THE INVENTION
Embodiments of the present disclosure present technological improvements as solutions to one or more of the above-mentioned technical problems recognized by the inventor in conventional practices and the existing state of the art.
The present invention relates to the testing of fuel-powered and hybrid or electrified vehicles in test laboratories by using dynamometers and other kinds of dynamometers and testing stands.
The hybrid or electric vehicle has drive and control systems that include an engine as the main motive drive source, and an electric motor for a run, which serves also as an electrical generator. Various sensors are provided at the constituent elements of the drive and control systems of the hybrid or electric vehicle, these sensors being capable of detecting as vehicle data the conditions of the vehicle, as typified by such items as the running speed, the accelerator input, the brake pedal stroke, the shift position, the brake fluid pressure, the electronic control throttle opening, the step less transmission for gear shift position, the step less transmission electromagnetic clutch operation, the running motor output electrical power, the running motor generated electrical power, the battery voltage, the battery charging power, the battery discharging power, the auxiliary clutch operation, and the auxiliary motor rpm. This vehicle data is input to a controller that is mounted in the vehicle and can be output to outside the vehicle, via the output section of a connector.
A dynamometer is used to test the drive and control systems of the above-noted fuel-powered and hybrid or electric vehicle. The provided dynamometer has different types of combination in arrangements of rollers that provide input for the front and/or rear or all wheels of the hybrid or electric vehicle. The system uses a plurality of sensors, at least one processing unit, at least one memory, at least one database, at least one server module, at least one web application, at least one central automation unit, and dynamometer controllers to control the operations of the dynamometer, driving robot, vehicle or the test sample, power analyser or PEMS (Portable emission measurement system). The power of the battery pack can be simulated by controlling the voltage and current output of high power. Additionally, the torque output of the Internal Combustion Engine (ICE) and drive train of the electric vehicle can be simulated in vehicle testing. The present invention provides a system and method for accurate replication and emulation to determine performance, emissions, range, and recuperation energy levels on electrified vehicles from on road to test laboratories in all kind of dynamometer and testing stands.
The full set of real-world test conditions, inclusive of the following distance behind lead vehicles and environmental conditions are either reproduced with reference to a prior real-world drive or simulated as desired in the laboratory environment. The mass emissions or energy efficiency, depending on power train type, and other automated longitudinal control performance parameters are noted and recorded. Subsequent tests can be used to calibrate or improve the emissions, efficiency, or other performance measures of the vehicle
If either PEMS emissions data or energy consumption was optionally collected for those methods including real-world driving, the PEMS data can then be directly compared with the laboratory emissions or energy consumption data collected during the laboratory test under the same conditions to ensure they are equal, within an acceptable range. This optional “validation” process serves to document a high degree of confidence that both the laboratory and real-world measurements are both correct and reproducible.
BRIEF DESCRIPTION OF THE DRAWINGS
The embodiments can be better understood with reference to the following drawings and descriptions. The components in the figures are not necessarily to scale, the emphasis instead being placed upon illustrating the principles of the embodiments. Moreover, the figures, like reference numerals designate corresponding parts throughout the different views.
Reference will be made to embodiments of the invention, examples of which may be illustrated in the accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
The above and other objects, features, and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Figure 1 illustrates a schematic elevation of a layout of a typical dynamometer for the testing vehicles.
Figure 2 illustrates a workflow diagram of on-road testing of a system and method for testing of a fuel-powered and hybrid or electric vehicle according to one of the embodiments of the present invention.
Figure 3 illustrates a workflow diagram of road test replication of a system and method for testing of a fuel-powered and hybrid or electric vehicle according to one of the embodiments of the present invention.
Figure 4 illustrates a workflow diagram of road test emulation of testing of a system and method for testing of fuel-powered and hybrid and electric vehicles according to one of the embodiments of the present invention.
Figure 5 illustrates stage wise block diagram system and method for accurate replication and emulation to determine performance, emissions, range, and recuperation energy levels on electrified vehicles from on road to test laboratories for a dynamometer according to one of the embodiments of the present invention.
Figure 6 illustrates the operation of dynamometer AP operation in accelerations and DP operation in deceleration which makes energy balance a perfect match with respect to on road conditions.
Figure 7 illustrates the closer look of operation of the dynamometer AP operation in accelerations and DP operation in deceleration which makes energy balance a perfect match with respect to on road conditions.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the embodiments.
As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.
In the following description, for the purpose of explanation, specific details are set forth in order to provide an understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without these details. One skilled in the art will recognize that embodiments of the present invention, some of which are described below, may be incorporated into a number of systems.
The various embodiments of the present invention provide a system and method for accurate replication and emulation to determine performance, emissions, range, and recuperation energy levels on electrified vehicles from on road to test laboratories by using all kinds of dynamometer and testing stands. Therefore, the disclosed system provides accurate replication and emulation for testing electrified vehicles in test laboratories by using all kinds of dynamometer and testing stands.
Furthermore, connections between components and/or modules within the figures are not intended to be limited to direct connections. Rather, these components and modules may be modified, re-formatted or otherwise changed by intermediary components and modules.
The systems/devices and methods described herein are explained using examples with specific details for better understanding. However, the disclosed embodiments can be worked on by a person skilled in the art without the use of these specific details.
Throughout this application, with respect to all reasonable derivatives of such terms, and unless otherwise specified (and/or unless the particular context clearly dictates otherwise), each usage of:
“a” or “an” is meant to read as “at least one.”
“the” is meant to be read as “the at least one.”
References in the present invention to “one embodiment” or “an embodiment” mean that a particular feature, structure, characteristic, or function described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
Embodiments of the present invention include various steps, which will be described below. The steps may be performed by hardware components or may be embodied in machine-executable instructions, which may be used to cause a general-purpose or special-purpose processor programmed with the instructions to perform the steps. Alternatively, steps may be performed by a combination of hardware, software, firmware and/or human operators.
Various methods described herein may be practiced by combining one or more machine-readable storage media containing the code according to the present invention with appropriate standard computer hardware to execute the code contained therein. An apparatus for practicing various embodiments of the present invention may involve one or more computers (or one or more processors within the single computer) and storage systems containing or having network access to a computer program(s) coded in accordance with various methods described herein, and the method steps of the invention could be accomplished by modules, routines, subroutines, or subparts of a computer program product.
In some embodiments, the systems may be configured as a distributed system where one or more components of the system are distributed across one or more networks in the testing system.
If the specification states a component or feature "may", "can", "could", or "might" be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
As used in the description herein and throughout the claims that follow, the meaning of "a'', ''an," and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise.
Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this invention will be thorough and complete and will fully convey the scope of the invention to those of ordinary skill in the art. Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure).
While embodiments of the present invention have been illustrated and described, it will be clear that the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the invention, as described in the claim.
In an embodiment, the present invention provides a system and method for accurate replication and emulation to determine performance, emissions, range, and recuperation energy levels on electrified vehicles from on road to test laboratories by using any kinds of dynamometer and testing stands.
In an embodiment, the present invention provides a system and method thereof for testing of electrified vehicles in test laboratories by using all kinds of dynamometer and testing stands that is useable, scalable and independent of complicated technological mechanism, uses minimum resources that are easy and cost-effectively maintained and can be implemented anywhere in vehicle testing systems.
Historically, the verification, validation and controller calibration of vehicles was brought in from the proving grounds to the laboratory using dynamometers simulating the road. The difficulty with such arrangements is that the entire vehicle needs to have all its intended components in a pre-production state. By expanding the simulation capabilities of the dynamometer controller to include simulation of missing subsystems not under development, subsystem or component testing can occur anywhere on a dynamometer which can be conveniently connected. In certain scenarios, a vehicle's kinematic characteristics, such as tires, differential, transmission, and torque converter are simulated for their power flow to result in torque or speed set points to a dynamometer attached to an internal combustion engine (ICE) which is nothing but the output provided by the internal combustion engine (ICE). However, the fuel cell or electrified vehicle suffers from the lack of availability of the internal combustion engine (ICE) and instead of internal combustion engine it utilises the battery pack intended in the vehicle. Both systems have high-value and sophisticated subsystems undergoing their own development process involving different parts of the organization and supplier network. Electric motors are also being considered at other locations in the drive train. They can be located in the wheels, differential, transmission, or front-end accessory drive system. These various alternatives add to the complexity of integration and calibration for the vehicle, thus it requires very early testing in the development process. The power of the battery pack can be simulated by controlling the voltage and current output of high power. Additionally, the torque output of the Internal Combustion Engine (ICE) and drive train of the electric vehicle can be simulated in vehicle testing.
Referring FIG. 1, illustrates atypical layout of the dynamometer for a testing system of the vehicle. The system comprises a plurality of sensors, at least one processing unit, at least one memory, at least one database, at least one server module, at least one web application, at least one central automation unit, dynamometer controllers to control the operations of the dynamometer, driving robot, vehicle or the test sample, power analyser or PEMS (Portable emission measurement system), at least one cooling fan and climatic chamber and/or Altitude simulator.
The system for testing vehicles by dynamometer consists of Web-based Application(1). This web-based application (1) platform is flexible and consists of many applications which enable the user to integrate all measurements of the different systems seamlessly and completely, test beds and specimens, as well as onboard systems in the laboratory. It helps and supports accomplishing many test automation activities. The Applications are mainly used to align the data from different sources. It also build the test and execute with a pre-defined workflow and sequence of processes. It also acts as a cloud-based storage server for test data.
The system for testing vehicle by dynamometer consists of Central Automation Unit (2). An automation system is needed to ensure that all devices inside the test cell like dynamometer, emission measurement system like motor exhaust analyser, dilution tunnel, particulate mass, particulate number measurement devices and other test cell peripherals are integrated into one central host system from which operator controls, give demands, receive feedback, and log all available parameters to generate data reports as and when required. This automation system is also configured to monitor instrument boundary conditions, test limits and health status checks of all integrated equipment.
The system for testing vehicle by dynamometer consist of Dynamometer Controller (3). This is a dedicated controller which ensures the correct usage of the dynamometer. It enables the dynamometer to follow the set demands as requested by the automation system either in a test cycle mode or as per manual inputs given by the user. This controller is a communication interface between the dynamometer motor and inverter. It precisely converts the demand from the automation system and feeds it to the inverter in a readable format to control the motor.
The system for testing vehicle by dynamometer consist of Dynamometer (4). This device is required to simulate real road load conditions inside the test cell. By using Dynamometer (4) vehicle is tested by mounting the vehicle with the help of mounting accessories like wheel chocks, strap system, etc. The dynamometer can be operated in different modes depending on test requirements such as ASR(Automatic Speed Regulation), ALR (Automatic Load Regulation), and ATR (Automatic Torque Regulation). Vehicle experiences the same road load driving condition inside a test cell. Apart from providing load, it can also provide a gradient to simulate uphill and downhill conditions.
The system for testing vehicles by dynamometer consists of a driving robot (5). This is a driver robot that performs an un-manned operation to drive the vehicle in extreme conditions (i.e.-20 deg C to 60 deg C, Accurate pedal playback in the lab, Battery range test, etc.) Driving robot is integrated with an automation system to receive test cycle demands either in terms to follow vehicle speed and gear or vehicle pedals and gear inputs. Vehicles are also driven by the Human depending on the requirement.
The system for testing vehicles by dynamometer requires a vehicle (6) that needs to be tested. The test sample is under development. For example in case of the engine dynamometer engine can be tested the test sample will be an engine and in power train dynamometer the test sample will be power train. Accordingly any kind of vehicle, engine, transmission system or power train system can be tested.
The system for testing vehicle by dynamometer consist of Power Analyzer/PEMS (Portable emission measurement system) (hereinafter referred as PEMS) that measures the pollutants and the power analyser is a device that measures motor and battery voltage and current during consumption and regeneration in case of electrified vehicles. PEMS is battery operated system that logs CO, CO2, NO/NOx, THC, CH4, NMHC, PN emission, N2O, HCHO, NMOG, NH3, Brake dust and tire particles, GPS data (Speed, Altitude, Longitude) & Ambient data (Temperature, Humidity, Pressure), Exhaust flow data, ECU data etc. Power analyser is equipped with external current sensors to identify the current and the voltage with the help of direct voltage measurement other attributes like apparent power, real power, reactive power, Id/Iq resolution and other parameters can be evaluated. It is integrated with host automation to log data for future use.
The system for testing vehicle by dynamometer consist of Altitude simulator(8) and /or Climatic chamber (10). Altitude simulator(8) and/ or Climatic chamber (10) are used to change the atmospheric conditions such as pressures, temperatures, and humidity to replicate the ambient conditions from on road testing to the laboratory. It is extensively needed to replicate different atmospheric conditions so that a performance of vehicle can be validate in extreme weather conditions.
The system for testing vehicle by dynamometer consists of a cooling fan (9). This cooling fan is situated inside the test cell which provides sufficient airflow to cool the vehicle during operation. This fan can be operated in various modes like manual, offset, and proportional with respect to dynamometer speed. The vehicle cooling fan is equipped with a braking resistor to decelerate the cooling fan speed during braking operation on the dynamometer when running in proportional mode.
The system for testing vehicles by dynamometer uses road load simulation which is a conventional method used by OEMs, regulatory authorities, and test laboratory providers to develop and certify vehicles respectively for regulatory requirements. During this Coast down method, Coast down values are to be generated on road with standard specified and defined conditions. (Ex: Defined vehicle weight, flat road surface with no gradients, standard ambient conditions, no cross-air wind conditions, standard road conditions and many others). Coast-down values are provided to test laboratories to adapt it into the lab which is called coast-down adaptation. This adaptation in the laboratory ensures to provide the equivalent reactive forces in the laboratory which is the same as on road conditions. This procedure is mainly applicable to regulation cycles like Modified Indian Driving Conditions (MIDC) , New European Driving Conditions (NEDC) , and Worldwide Harmonized Light Vehicles Test Procedure (WLTP). However, there is the main challenge for OEMs to make valid Real Driving Emissions (RDE) (hereinafter referred to as RDE) tests by meeting RDE testing criteria specified by regulation authorities which consumes more time and effort. To ease the development of vehicle emissions, the only way is to playback on-road tests in laboratories for faster and more efficient development of vehicle programs. While replicating the RDE tests in laboratories this will not work well with the coast-down method, the reason being the additional loads due to gradients, crosswinds, cornering, and ambient conditions cannot be predicted and controlled in a realistic manner. It is possible to estimate additional loads, but accuracy levels are very poor which will be a challenging task for OEMs to continue their vehicle development in laboratories in the right direction. Another method known as the Torque matching methodology can be used for the replication of on-road trails to laboratories. In the Torque matching method pedal (Clutch, Brake, Accelerator) from on-road trials, engine speed, vehicle speed, ambient temperature, pressure, and relative humidity is recorded from on-road trials and it is replicated in laboratories with the use of different products, systems, and solutions. In this method there is no information required for road gradient or surface, everything is recorded by the accelerator pedal and it is replicated in the lab to match the loading on the vehicle. All the set points are based on the actual RDE test measurements from on-road trials. The torque matching method is very superior to the conventional road load simulation method and works well with Internal combustion engines but due to different technologies used in electric vehicles, it is not completely accurate and not useful for testing electric vehicles. There is a necessity of all important parameters needs to be operated with the Torque matching method i.e., engine speed will be matched by a combination of vehicle speed & gear no operation, and vehicle speed is matched by the Dynamometer independent of the operation of pedals and pedal data is matched by the Autopilot. Therefore, it works well with conventional engines but in the case of electrified vehicles, recuperation energies play a major role in conversing the energies and charging the battery pack and subsequent increase in the State Of Charge (SOC) of the battery and hence the range of the vehicle. Due to this there are limitations in torque matching as the vehicle speed is controlled in deceleration phases independent of brake pedal operation. To achieve the best results basically, there are two types of recuperation are possible in the case of electrified vehicles: the first method is Mechanical Brake pedal operation (Accelerator pedal + Brake Pedal) and the second method is E-Pedal operation (One Pedal for both Acceleration and Deceleration + Brake pedal is used only to make the vehicle to stop conditions and not acts like a conventional brake).
In both the methods replication and emulation of brake pedals from the torque matching method is not so accurate because the dynamometer follows the set point of vehicle speed in both the acceleration and deceleration phase which is derived from on-road trials. In this scenario recuperation energies are not equal what is being generated on-road trials which is not a robust solution.
In the conventional system of testing vehicles by the dynamometer, the displacement of the pedal can be either captured from the central automation unit or by a physical string potentiometer based on the feasibility. In case of vehicles equipped with combustion engines, especially in deceleration as there is no concept of recuperation energies. The energy available after the acceleration phase is directly transferred into braking energy afterwards which will be wasted as heat dissipation. On the other hand, in case of electrified vehicles, this energy available in the form of kinetic and potential energies will be recuperated and stored in the form of chemical energies inside the batteries to provide energy when vehicle needs it from the battery. Therefore, replication process needs to be carried in so accurate manner that every additional load shall be accurately replicated inside the laboratories to have the same performance as on road conditions.
Accordingly, there is a need for hybrid control of the dynamometer which includes combination of various dynamometer for accurate replication from on-road testing to laboratory testing.
In an embodiment, the present invention provides a system and method for hybrid control of dynamometer for accurate replication of performance, range, thermal behaviour, and other functional attributes of electrified vehicles (Hybrid Electric vehicles, Battery Electric Vehicles, Fuel Cell Electric Vehicles, and all other vehicles wherever recuperation energies play a vital role in the performance of vehicles. The disclosed system and method become the value addition for OEMs in the process of vehicle development. Therefore, by using this system and method the replication process is carried out so accurate manner so that every parameter of vehicle testing can be accurately replicated inside the laboratories to achieve the same performance as on-road conditions and minimizing the gap between the actual road resting and the simulated laboratory testing.
According to one embodiment of the present invention provides a system and method for accurate replication of performance, emissions, range, and recuperation energy levels on electrified vehicles from on-road to test laboratories for all kinds of dynamometer and testing stands for testing of Hybrid Electric vehicles, Battery Electric Vehicles, Fuel Cell Electric Vehicles, and all other vehicles wherever recuperation energies play a vital role in the performance of vehicles.
Figure 2 illustrates the functional flow diagram of the on-road test according to an exemplary implementation of one of the embodiments of the present invention. The system and method of the present invention consisting a first stage which includes on road test of the vehicle. The system comprises a plurality of sensors, at least one processing unit, at least one memory, at least one database, at least one server module, at least one web application, at least one central automation unit, vehicle, or the test sample, PEMS /power analyser. The system and method of the present invention comprise inspection of the vehicle which includes checking for any physical damage to the vehicle or any essential component of the testing equipment. The method includes checking engine oil, fuel level, filters, etc, or other consumables which are basic necessary requirements for the trial run or test run. The method includes measurement of devices for installation feasibility and checking the Battery status and checking necessary ECU communication workings etc.
The method further includes obtaining the necessary data, installing of measurement devices which includes a GPS sensor to identify the position of the vehicle in altitude/longitude/latitude directions. The temperature/humidity sensors for obtaining atmospheric conditions of the test environment. The PEMS unit for emission measurement and PF tubes for Exhaust flow rate measurement. The String pot is used for pedal position measurement and the power analyser is for analyzing the battery performance of the vehicle. The On Board Diagnostics (OBD) data is obtained from Electronic Control Unit (ECU) data logging.
The method includes an on-road tests and data logging during the test for obtaining Time, GPS data, Altitude & Ambient condition, Exhaust Flow, Emission data, OBD data, Pedal position data, Power analyser data, battery status, recuperation status, etc. The method further includes exporting test data to the web-based applications. The method further includes moving to the second stage for replication of on-road test.
Figure 3 illustrates the functional diagram of the replication of on-road data inside the laboratory according to an exemplary implementation of one of the embodiments of the present invention. The second stage of the method is a replication of on-road data inside the laboratory. The main purpose of the replication stage is to have closer replication of on-road data inside the laboratory, and to proceed with the emulation stage to run the same cycle with the same load to develop power train systems very rapidly. The system comprises of a plurality of sensors, at least one processing unit, at least one memory, at least one database, at least one server module, at least one web application, at least one central automation unit, dynamometer controllers to control the operations of the dynamometer, driving robot, vehicle or the test sample, power analyser or PEMS (Portable Emission Measurement System), Altitude Simulator and/or climatic chamber and at least one cooling fan. The method includes performing a vehicle setup in the test lab with the same measurement device used during the road test. The method includes installing the driving robot and performing necessary settings and configuration according to requirements and configuration available in the system. The method further includes preparing the Altitude simulator and/or Climatic chamber and connection setup for required different atmospheric conditions. This process is not only required for internal combustion engine (ICE) vehicles but in electric vehicles, atmospheric conditions are need to be considered as the battery performance is dependent on different environmental conditions.
The method further includes exporting on-road test data to the web-based application which includes data alignment and synchronization and the creation of test. The data obtained from on-road data channels is used for test creation which includes Time, Vehicle speed, Engine speed, Gear, Pedal position, Ambient Temperature, Humidity, and altitude , Recuperation status for xEVs, Identification of acceleration phase(AP) (hereinafter referred as AP mode) and deceleration phase(DP)(hereinafter referred as DP mode) and Estimated loads for DP mode is taken into consideration for precise results.
The method further includes importing a test file for the central automation system on the dynamometer for AP/DP mode status, Speed, and gradient data / Robot for AP/DP mode status. In this process all pedal set points and ambient simulator which includes Temperature, Humidity and Altitude set points are taken into consideration for appropriate results. The method further includes conducting a test run by considering exactly the same set points. The test is mainly categorized into two parts one part is in AP mode which is acceleration mode in which the dynamometer includes Automatic Speed Regulation(ASR) (hereinafter referred ASR) mode follows all speed set points independent of load. In this process Robot performs a playback pedal for its set points and the Altitude simulator and/ or climatic chamber set the points of atmospheric conditions as per requirement which include Temperature, Humidity, Altitude and other essential factors. The other part is in DP mode i.e. Deceleration mode in which Dynamometer includes Automatic Load Regulation(ALR) (hereinafter referred as ALR) mode and follows load set points. In this process, Robot performs a pedal operation to achieve speed set points and in Altitude simulator and/or climatic chamber replicates the set points which include Temperature, Humidity and Altitude and other essential factors. In the end process, the test is finished and the method further includes analyzing data. In data analysis, if results are within criteria (±2%) then it saves test data and dynamometer load values and exports the data to the web-based application so that it is prepared for the third stage which is emulation or else if required by estimating new load values test can be repeated.
Figure 4 illustrates the functional flow diagram of the emulation of data inside the laboratory according to an exemplary implementation of one of the embodiments of the present invention. The third stage of the method is an emulation of data inside the laboratory. The main purpose of the emulation stage is to ensure to run same test cycle (with the same work done- from load values measured from the second stage ) with different calibration strategies like hardware components which may include E-Motor, Inverter, Fuel Cell, Battery, Tyres, any other engine, or power train components. The user may use different software like set points according to requirements so that it is easy to make any combination to conduct a vehicle test.
The method includes exporting a data to the web-based application which includes recording test data containing time, pedal positions, speed, gear, load values, temperature, humidity, and Altitude with Dynamometer load values and many other required data in second stage replication. The method further includes importing a test file in the central automation system and conducting a test run for obtaining desired results.
The method further includes operation mode in which Dynamometer mode uses (ALR) and applying the same load recorded which is recorded in the second stage. The robot operates the pedals to achieve speed set points, and the Altitude simulator and/or climatic chamber replicate the atmospheric set points mainly temperature, humidity and altitude. In end process finish the vehicle test for required parameter. The method further includes if the results are not achieved in a satisfactory manner then the user may change calibration and user may replace parts and control modules. The method further includes repeating or conducting tests again until the development requirement is satisfied. Therefore, the disclosed system and method enable OEMs to develop, test and validate the power train configurations very rapidly with minimum time and effort.
Figure 5 illustrates the stage-wise block diagram of system and method for accurate replication and emulation to determine the performance of vehicle, emissions, range, and recuperation energy levels on electrified vehicles from on-road to test laboratories by using all kind of dynamometer and testing stands for testing of Hybrid Electric vehicles, Battery Electric Vehicles, Fuel Cell Electric Vehicles, and all other vehicles wherever recuperation energies play a vital role in the performance of vehicles. The system and method of the present invention consisting a first stage which includes on-road test of the vehicle. The second stage includes replication of on-road data inside the laboratory and the third stage includes the emulation of data for all kinds of dynamometer and testing stands for accurate replication from on-road testing to laboratory testing.
Advantages of the invention
· The disclosed system provides vehicle testing system for accurate replication and emulations of all functional attributes from on road to the Laboratory to rapidly develop vehicles and minimize the time and efforts required to complete vehicle development.
· The disclosed system provides vehicle testing system that saves time and effort are equivalent to savings of development costs.

The processes, methods, or algorithms disclosed herein may be deliverable to or implemented by a processing device, controller, or computer, which may include any existing programmable electronic control unit or dedicated electronic control unit. Similarly, the processes, methods, or algorithms may be stored as data and instructions executable by a controller or computer in many forms including, but not limited to, information permanently stored on non-writable storage media such as ROM devices and information alterably stored on writeable storage media such as floppy disks, magnetic tapes, CDs, RAM devices, and other magnetic and optical media. The processes, methods, or algorithms may also be implemented in a software executable object.
Further, while one or more operations have been described as being performed by or otherwise related to certain modules, devices or entities, the operations may be performed by or otherwise related to any module, device or entity.
Further, the operations need not be performed in the disclosed order, although in some examples, an order may be preferred. Also, not all functions need to be performed to achieve the desired advantages of the disclosed system and method, and therefore not all functions are required.
While selected examples of the disclosed system and method have been described, alterations and permutations of these examples will be apparent to those of ordinary skill in the art. Other changes, substitutions, and alterations are also possible without departing from the disclosed system and method in its broader aspects.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, thereby enabling others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the scope of the present invention.

WE CLAIM:

1. A system for testing a fuel powered and hybrid or electrified vehicle, the system comprising:
a plurality of sensors; at least one processing unit; at least one memory; at least one database; at least one server module; at least one web application; at least one central automation unit; dynamometer controllers to control the operations of dynamometer; driving robot; vehicle or the test sample; power analyzer or PEMS (Portable emission measurement system); Altitude simulator and/or Climatic chamber, at least one cooling fan
characterised in that said web application aligns the data from the data central automation module, build the test and execute with a pre-defined workflow and sequence of the processes for replication of on road test on dynamometer by importing a test file from central automation module for AP/DP mode and exporting the data to web-based application for emulation and conduct a test run to obtain desired results.
2. The system as claimed in claim 1 wherein the plurality of sensors are configured for testing a fuel powered and hybrid or electrified vehicle for all parameters of internal combustion engine in fuel powered vehicle or electric drive train of electric vehicles, for obtaining live parameters comprising battery voltage and current during consumption and regeneration CO, CO2, NO/NOx, THC, CH4, NMHC, PM, PN,N2O, HCHO, NMOG, NH3, Brake dust and tire particles, PN emissions, GPS data (Speed, Altitude, Longitude) & Ambient data (Temperature, Humidity, Pressure), Exhaust flow data, ECU data, OBD data, Pedal position data, Power analyser data, recuperation status etc.
3. The system as claimed in claim1 wherein the plurality of sensors configured to detect and/or measures the plurality of parameters, convert the measured plurality of parameters into proportionate electrical signals and communicate said electrical signals to the processing unit.
4. The system as claimed in claim 1 wherein the processing unit comprises at least one processer and at least one memory communicatively coupled to it, the processing unit electrically coupled to the plurality of sensors, said processing unit configured to communicate with the plurality of sensors to receive the captured parameters in the form of proportionate electrical signals in real time and analyze and process them.
5. The system as claimed in claim 1 wherein the at least one database is configured to acts as a real time database, said database communicatively coupled to the at least one processing unit to fetch the processed signal information of the data from the sensor through the processing unit, store the received signal information and communicate it through the Web base Application to the data central automation module.
6. A method for testing a fuel powered and hybrid or electrified vehicle, the method comprising steps of:
? inspecting vehicle condition and checking engine and battery parameter to conduct a test;
? installing measurement sensors to obtain time, GPS data, Altitude & Ambient condition, Exhaust Flow, Emission data, OBD data, Pedal position data, Power analyser data, battery status, recuperation status;
? conducting on-road test and data logging to record data which includes time, GPS data, Altitude & Ambient condition, Exhaust Flow, Emission data, OBD data, Pedal position data, Power analyser data, battery status, recuperation status .
? exporting the recorded test data to web-based application for replication and emulation of on road test on dynamometer;
? performing a vehicle setup in test lab with same measurement device used during road test;
? installing the driving robot and performing necessary settings and configuration according to requirement and configuration available in the system;
? preparing the Altitude simulator and/or climatic chamber and connection setup for required atmospheric conditions;
? conducting a test run by considering exactly same set points of on road test in AP/DP mode wherein dynamometer performing test in ASR and ALR mode;
? recording and analyzing a data which is obtained from conducted test ;
? saving a test data and dynamometer load values and exporting the data to web-based application for emulation or estimating new load values test;
? applying same load recorded which is recoded in conducted road test for replication;
? repeating or conducting test for different combination or configuration for validation.