TECHNICAL FIELD
The subject matter described herein, in general, relates to an ignition system for an internal combustion (IC) engine and, in particular, relates to a controlled ignition system with multiple ignition units, for an IC engine. BACKGROUND
Ignition systems for conventional IC engines primarily include two types of ignition units namely a capacitive discharge ignition (CDI) unit and an inductive discharge ignition (IDI) unit. The CDI unit can be either an alternate current (AC) CDI unit or a direct current (DC) CDI unit based on the source voltage.
The AC CDI unit provides high reliability, high spark energy, accurate ignition timing, and longer life. However, in certain implementations of the IC engine such as a two-wheeled vehicle, working of the AC CDI unit depends on the output of a magneto, which in turn depends on the revolutions-per-minute (RPM) of the engine. Hence, at lower engine RPM, the AC CDI unit does not charge up completely and results in incomplete combustion. Consequently, a starting problem may also occur in the AC CDI unit.
On the other hand, the DC CDI unit provides, in addition to all the advantages of the AC CDI unit, zero starting trouble. The starting trouble is eliminated in this unit as the capacitor is charged to a high voltage from a direct current source that is independent of the RPM of the engine, such as a battery. However, a disadvantage of the DC CDI unit is that it causes additional loading on the battery of the vehicle.
Both the CDI units provide a high initial spark voltage which avoids leakage across a spark plug., However, the high initial spark voltage provides less energy for a sufficiently long

spark duration. Further, short spark duration may not be sufficient for complete combustion of a lean air-fuel mixture.
In the IDI unit, the ignition voltage is generated by the sudden injection of the current through a primary winding of an ignition coil. The IDI unit provides a longer spark duration, which ensures complete combustion, especially of a lean, non-homogenous air-fuel mixture. However, at high engine RPM, the ignition coil may not charge up completely before the coil is caused to discharge, hence limiting the voltage and the energy available for producing a spark.
An ignition system may also be configured to act as a single spark ignition system or a multiple spark ignition system. The single spark ignition system, implemented typically in small bore IC engines, employs an AC CDI unit, a DC CDI unit or an IDI unit, to provide a single spark that ionizes a spark gap, thereby creating an electrically conductive plasma. Most of the energy of the spark is delivered quickly following ionization, and after which the energy of the spark gradually decreases. The reduced energy of the spark is unable to produce a high current for sustaining the plasma which results in incomplete combustion and reduced fuel economy.
The multiple spark ignition system provides multiple sparks for a single cycle of combustion, in order to achieve a sustained plasma. However, owing to various design and space constraints typical multiple spark ignition systems involve either a CDI unit or an IDI unit and therefore have functional limitations at different RPMs. For example, the energy storage device of the ignition unit does not get sufficient time in between two consecutive firings to ramp up to the maximum voltage, thereby resulting in weaker sparks and loss of power. Additionally, generation of multiple sparks produce additional load, which reduces the life of the ignition unit, fhus, the conventional ignition systems are incapable of providing efficient combustion at all operating conditions of the IC engine.

SUMMARY
The subject matter described herein is directed to a controlled ignition system (CIS) for an internal combustion (IC) engine, such as a small bore IC engine. The CIS is employed for controllably generating sparks across a spark generation device, based on the IC engine's operation and requirements.
In one embodiment, the CIS is implemented in the IC engine of a two-wheeled vehicle. The CIS includes multiple ignition units and a control unit. The control unit is configured to receive signals from multiple sensors that sense various engine conditions. Based on the sensed engine conditions and a predetermined logic of the control unit, the control unit selects one or more of the ignition units and enables the selected ignition units to discharge through an ignition coil. The discharge of the selected ignition unit(s) produces a spark across a spark generation device, for example, a spark plug.
The CIS described herein, based on engine requirements, may trigger different ignition units at different instants, in various combinations and sequences to produce a plasma of desired energy and duration. Thus, the CIS provides a sustaining plasma across a combustion chamber of the IC engine, thereby providing sufficient energy for efficient combustion at all engine conditions. The CIS is efficient, reliable, and requires low maintenance.
These and other features, aspects, and advantages of the present subject matter will be better understood with reference to the following description and appended claims. This Summary is provided to introduce a selection of concepts in a simplified form. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor it is intended to be used to limit the scope of the claimed subject matter.

BRIEF DESCRIPTION OF DRAWINGS
The above and other features, aspects, and advantages of the subject matter will be better understood with regard to the following description, appended claims, and accompanying drawings where:
Fig.l shows a perspective view of an exemplary two-wheeler implementing a controlled ignition system (CIS), according to an embodiment of the invention.
Fig.2 shows a block diagram representation of the CIS, according to an embodiment of the present subject matter.
Fig.3 shows a block diagram representation of a control unit of the CIS of Fig.2.
Fig.4 shows a flow chart representation of the working of the CIS.
DETAILED DESCRIPTION
The subject matter described herein relates to a controlled ignition system (CIS) for an internal combustion (IC) engine. The IC engine may be a small bore IC engine used in various applications such as vehicles, gen-sets, lawnmowers and so on. However, for the purpose of explanation and by no way of limitation, the CIS has been explained in context of an IC engine of a two-wheeled vehicle.
The CIS includes multiple ignition units and a control unit. The control unit selectively causes one or more of the multiple ignition units to discharge for producing a spark across a spark generation device. The spark facilitates ignition of a compressed air-fuel mixture inside a combustion chamber of the engine. The selection of the one or more of the ignition units is based on a predetermined logic implemented in the control unit. Further, the CIS may be operated in a single ignition mode as well as a multiple ignition mode.

The CIS as described herein improves overall ignition performance of the engine by enhancing both energy and duration of a spark event. The CIS can thus provide a sustaining plasma across the combustion chamber, thereby providing sufficient energy to ensure complete combustion.
For the purpose of explanation, the CIS of the present subject matter has been described with respect to two ignition units; however, it would be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, the CIS may comprise more than two ignition units in one embodiment.
Fig.l shows a perspective view of a two-wheeled vehicle in which the CIS (not shown in the figure) has been implemented, with respect to one embodiment of the present subject matter. The embodiments disclosed herein are described in the context of a step-through two-wheeler 100. However, the embodiments and the subject matter herein can also be applied to other vehicles, such as step-over two-wheelers, all terrain vehicles, and other vehicles, such as three-wheelers.
As used herein, the terms "front", "rear", "left", "righf, "up", and "down", correspond to the position assumed by a rider of the two-wheeler 100 with respect to the direction in which he is facing. The two-wheeler 100 includes a frame 105 for supporting a handlebar 110 disposed towards a front end thereof The frame 105 or chassis 105 is supported on a front wheel 115 and a rear wheel 120 at two distant ends of the two-wheeler 100, respectively. An IC engine 125, along with other associated components such as a transmission system 130, is mounted on the frame 105. The IC engine 125 employs the CIS as the ignition system. The IC engine 125 also

employs a magneto (not shown in Figure) which may function as a primary power source for the CIS.
Fig 2 shows a block diagram representation of a CIS 200, according to an embodiment of the present subject matter. The CIS 200 includes a plurality of ignition units 205. In the present implementation, a first ignition unit 205-1, and a second ignition unit 205-2, also referred to as ignition unit 205, have been depicted. The ignition unit 205 may be an AC CDI unit, DC CDI unit, IDl ignition unit or any other ignition unit known in the art, depending on the preferences of a user. The first ignition unit 205-1 and the second ignition unit 205-2 may include an ignition • controller 210-1 and an ignition controller 210-2 respectively, also referred to as ignition controller 210. All the ignition units 205 are operably connected to a control unit 215.
The control unit 215 receives signals from a plurality of sensors (not shown) that sense various engine conditions. Based on the sensed engine conditions and a predetermined logic implemented in the control unit 215, the control unit 215 selects one or more of the ignition units 205 to be discharged into a spark generation device 217, such as a spark plug. For purposes of discussion, the spark generation device 217 is interchangeably referred to as spark plug 217 hereinafter.
In one implementation, the sensors include a pulser coil 220 that senses the position of the piston of the IC engine 125 and provides an engine RPM signal to the control unit 215. Further, the pulser coil 220 provides timing signal to the ignition units 205. Alternatively, it will 3e understood that any other sensor, which can synchronize spark generation with respect to 3PM of the engine 125 may be used.
In the above implementation, upon being enabled by the control unit 215 and on eceiving the timing signal from the pulser coil 220, the ignition controller 210 determines the

piston position of a corresponding cylinder of the engine 125, and accordingly discharges the selected ignition unit 205 into an ignition coil 230. In other words, the instance of discharging the energy of an energy storage device (not shown in the figures) of the selected ignition unit 205 is determined by the corresponding ignition controller 210.
The ignition controller 210 contains the information regarding the instance of discharging of the corresponding ignition unit 205 i.e. at what piston position the selected ignition unit 205 is to be discharged. For example, the ignition controller 210-1 may discharge the selected ignition unit 205-1 to fire a first spark, when the piston is a few degrees below TDC. In addition, the ignition unit 205-2 may be selected by the controller unit 215 to fire a second spark, and the ignition controller 210-2 may discharge the second selected ignition unit 205-2 simultaneously with the first selected ignition unit 205-1 or after a predetermined time gap of the first selected ignition unit 205-1.
In said embodiment, though the ignition units 205 directly receive the timing signal from the pulser coil 220; however, the discharge of energy from the ignition units 205 is enabled by the control unit 215. The control unit 215, based on the predetermined logic, selects and enables the discharge of energy from one or more ignition unit(s) 205. As a result, though the ignition units 205 receive the timing signal from the pulser coil 220 for every combustion cycle, the ignition units 205 discharge into the ignition coil 230 upon receiving a trigger signal from the control unit 215.
Upon receiving the trigger signal, the ignition controller 210 actuates a switch of the corresponding ignition unit 205, at the required piston position. The actuation of the switch initiates discharging of the energy storage device of the ignition unit 205. The switch employed for the purpose may a triac, thyristor, silicon controlled rectifier (SCR), or any other switch

known in the art. The energy storage device discharges energy stored in it through a primary coil of the ignition coil 230 to generate a very high voltage at a secondary coil of the ignition coil 230. The high voltage generated at the secondary coil causes a high voltage spark across the spark plug 217. Typically, the spark voltage has a value between 5kV and 20kV. This voltage creates a plasma across the spark plug 217 that results in combustion of the air-fuel mixture in the combustion chamber.
In another embodiment of the present subject matter, the pulser coil 220 is configured to provide the timing signal to the ignition units 205 as well as the control unit 215. In said embodiment, both control of the ignition timings and selection of the one or more ignition unit(s) 205 is controlled by the control unit 215. In one implementation of said embodiment, a first trigger signal for discharging the first ignition unit 205-1 is fired from the control unit 215 upon receiving the timing signal. The instance of triggering the second ignition unit 205-2 for the same combustion cycle is based on the predetermined logic stored in the control unit 215. For example, the control unit 215 may trigger the first ignition unit 205-1 upon receiving the timing signal from the pulser coil 220 and may trigger second ignition unit 205-2 simultaneously with the first ignition unit 205-1 or after a predetermined time period after the first ignition unit 205-1.
To generate a charge, the first ignition unit 205-1 and the second ignition 205-2 are connected to a first supply 235 and a second supply 240 respectively. The first supply 235 and the second supply 240 can be an AC source or a DC source depending upon the ignition unit type they are connected to. For example, if the supply 240 is connected to an AC driven ignition unit, the supply 240 would be an AC source. Similarly, if the supply 240 is connected to a DC driven ignition unit, the supply 240 would be a DC source.

For the purpose of explanation, the working of the CIS 200 is described in detail with the First ignition unit 205-1 being an AC CDI unit and the second ignition unit 205-2 being a DC GDI unit. Consequently, the first supply 235 is an AC source and the second supply 240 is a DC source. In one implementation, a magneto (not shown in the figure) disposed in the two-wheeler 100 serves as a primary power source for the first supply 235 and the second supply 240.
An armature of the magneto rotates with a crankshaft or a camshaft of the engine 125 to produce an AC voltage. The AC voltage generated by the magneto is fed to both, the first supply 235 and the second supply 240. In one implementation, the first supply 235 includes a step-up transformer for raising the voltage of the electrical energy received from the magneto up to 300V to 600V. fhe AC supply from the first supply 235 charges a capacitor of the first ignition unit 205-1 to a threshold voltage.
In case of the second ignition unit 205-2 being a DC CDI unit, the second supply 240 includes a rectifier circuit, a battery, and a pulse transformer. The second supply 240 rectifies the AC voltage received from the magneto to a DC voltage and provides the DC voltage to the second ignition unit 205-2 either directly through the pulse transformer or through the battery. In the latter case, the supply from the battery is supplied to the second ignition unit 205-2 through the pulse transformer. The battery can be any regular battery used in vehicles or an additional battery disposed for the purpose of the supplying charge to an energy storage device of the one or more ignition unit(s). In operation, the pulse transformer can produce a voltage of approximately 300V. The voltage from the second supply 240 charges a capacitor of the second ignition unit 205-2 to a threshold voltage.
In one embodiment the second ignition unit 205-2 is an IDI unit and the second supply 240 is consequently implemented as a DC source as explained above.

Fig.3 shows a block diagram representation of the control unit 215 of the CIS 200 of the Fig.2 and its working, according to an embodiment of the invention. In one implementation, the control unit 215 includes a processor 310, a memory 320, an analog-to-digital (A/D) converter 330, a digital to analog (D/A) converter 340, and a switching unit 350. The processor 310 and the switching unit 350 are shown here as two separate units; however, their functionality may be realized in a single unit as well. The control unit 215 controls the selection of the one or more ignition units 205-1, 205-2,... 205-n, also referred to as ignition units 205 as aforementioned. The control unit 215 selects the ignition unit(s) 205 by monitoring the engine's operation through the multiple sensors 360-1, 360-2, to 360-n, collectively referred as the sensors 360 hereinafter.
The control unit 215 can be configured to receive various signals from the sensors 360 regarding various parameters such as piston position, engine load, engine RPM, throttle position, engine manifold pressure, engines' air mass flow-rate, and so on. The sensors 360 may include manifold absolute pressure (MAP) sensors, throttle position sensors, engine RPM sensors, speed sensors, air temperature sensors, oxygen sensors, pulser coil sensors, etc. In one implementation, the sensor 360-1 may be the pulser coil 220. As mentioned previously, the pulser coil 220 provides the timing signal to the ignition unit(s) 205 and the engine RPM information to the control unit 215.
In operation, the A/D converter 330 in the control unit 215 serves as an interface between the sensors 360 and the processor 310. The sensors 360 sense the instantaneous value of the selected parameters and provide them to the A/D converter 330. The A/D converter 330 coverts analog signals received from the sensors 360 to digital signals to be further processed by the processor 310. The processor 310 processes the digital signals based on the predetermined logic of the control unit 215. The predetermined logic may be based on a variety of parameters like

engine load, engine RPM, piston position, throttle position, etc. The processor 310 compares the instantaneous value of the sensed parameter to a threshold value of the sensed parameter. The threshold values are selected so as to ensure an efficient combustion of the air-fuel mixture. The threshold values and the predetermined logic may be stored in the memory 320. The predetermined logic includes logic for selection of the ignition units 205 such that a selected permutation and combination of the ignition units 205 provides efficient combustion and hence better engine performance.
Further, based on the comparison of the instantaneous value of the selected parameters with the threshold values and using the predetermined logic, the switching unit 350 selectively triggers one or more of the ignition units 205. The switching unit 350 also determines the ignition unit(s) 205 to be triggered for firing the first spark and the ignition unit(s) 205 to be triggered for firing a second spark and so on, and accordingly provides the trigger signal to the selected ignition unit(s) 205. The D/A converter 340 converts a digital signal received from the switching unit 350 into an analog signal before passing the signal to the ignition unit(s) 205. Upon receiving the trigger signal from the switching unit 350, the corresponding ignition unit(s) 205 is enabled for discharging of the energy storage device of the ignition unit(s) 205. Once an ignition unit(s) 205 is enabled the instance of discharging is determined by the ignition controller 210 (shown in Fig.2).
In one implementation, the predetermined logic of the control unit 215 may be based on RPM of the engine 125. The control unit 215 receives a signal from one of the sensors 360 sensing the RPM, such as the pulser coil 220. The processor 310 determines whether the RPM is higher than a threshold RPM as stored in the memory 320. If the RPM is below the threshold RPM value, the switching unit 350, based on the predetermined logic, triggers a DC supply-

driven ignition unit, i.e., the DC CDI unit, of the ignition units 205. Further, if the RPM is found to be higher than the threshold value, the switching unit 350 triggers an AC supply-driven ignition module, i.e., the AC CDI unit, of the ignition units 205. In another implementation, when the RPM goes higher than the threshold RPM, the switching unit 350 triggers two or more ignition units 205. Further, the ignition controller(s) 210 may discharge the triggered ignition unit(s) 205 simultaneously or one after another i.e. sequentially.
In another implementation, the predetermined logic of the control unit 215 may be based on the engine load also. The control unit 215 may receive information regarding the engine load condition through one of the sensors 360, such as a throttle position sensor. The processor 310 determines whether the engine load is higher or lower than a threshold value of the engine load. If the engine load is found out to be lower than the threshold value of the engine load, the switching unit 350 triggers an appropriate ignition unit, such as the IDI unit, of the ignition units 205. As mentioned in earlier sections, the IDI unit is preferred for the combustion of a lean air-fuel mixture as the same provides a long spark duration, which ensures a better combustion under low load conditions.
Further, if the engine load is found out to be higher than the threshold value of the engine load, the switching unit 350 may trigger two or more of the ignition units 205. The triggered ignition unit may be an AC CDI unit, a DC CDI unit, or an IDI unit.
In operation, upon receiving a trigger from the control unit 215 and a timing signal from the sensor 360, the triggered ignition unit 205 may generate a first spark when the piston is a few degrees before the TDC. The first spark results in the ionization of a spark gap of the spark plug 217, thus creating an electrically conductive plasma. In order to achieve a sustained plasma, additional energy in the form of a second spark may be provided subsequent to the ionization.

The additional energy results in the plasma extending into the air-fuel mixture, which facilitates efficient and complete combustion. Further, if required, subsequent sparks can also be provided across the spark plug 217 (shown in Fig.2).
Depending upon the requirements of the engine 125 and the preferences of a user, the switching unit 350 may trigger one or more ignition units 205 within a single cycle of combustion. Accordingly, the CIS 200 may operate in a single ignition mode or a multiple ignition mode. In another implementation, the control unit 215 may combine the information provided by the sensors 360 and suitably trigger one or more of the ignition units 205. In yet another implementation, in case the supply of an ignition unit 205_n is not adequately charged, such as during the engine start up, the control unit 215 triggers another ignition unit 205_n, such as the DC CDl, which is adequately charged.
As mentioned previously, the conditions influencing the use of one or more ignition units 205 can be predefined in the control unit 215. Hence, one can understand that the most suitable of the ignition units 205 can be used based on the conditions and user preferences. Similarly, more than one ignition units 205 may be triggered when conditions are such that a sustained plasma is required for efficient operation of the engine 125. In an implementation, the control unit 215 may be an electronic control unit (ECU); however, a separate control unit 215 for controlling the ignition timing may also be provided.
In one more embodiment of the present subject matter, the IC engine 125 may include two spark plugs 217. In such a case, depending upon the engine conditions, the CIS 200 can be configured to generate two simultaneous sparks across both the spark plugs 217. Further, the CIS 200 may generate two or more sparks in a desired sequence based on the predetermined logic of the control unit 215. For example, the first ignition unit 205-1 may be triggered to spark one of

the spark plugs 217 and, after a predefined time gap, the second ignition unit 205-2 may be triggered to spark the other spark plug 217 and, if required, a third ignition unit may be triggered to generate a third spark using either of the two spark plugs 217, and so forth.
In accordance with an aspect of the present subject matter, the threshold values of the selected the parameters, the voltage and energy storing capacity of the energy storing device(s), etc., can all be adjusted to generate sparks of any desired energy distribution and duration.
Fig.4 illustrates an exemplary method 400 by way of a flow chart elucidating the working of an exemplary CIS, according to an embodiment of the subject matter. In a preferred embodiment, the method 400 is implemented in the aforementioned CIS 200 of Fig.2.
The method 400 is initiated at step 402 where the CIS is actuated. Upon actuation, at step 404 a control unit of the CIS senses selected engine conditions by utilizing a variety of sensors. In one implementation, the control unit is the control unit 215. The control unit receives signals from the sensors, such as the sensors 360, sensing the selected engine conditions.
At step 406, a sensor, such as the pulser coil 220, generates a timing signal, which is fed to the ignition unit(s). The timing signal provides information regarding a position of the piston of the engine. In one implementation, the timing signal is simultaneously provided to both the control unit and the ignition unit(s).
Upon receiving the timing signal, at step 408, it is determined whether the value of the sensed parameter is greater than a threshold value of the parameter. At step 408, if it is determined that the value of the selected parameter is lower than the threshold value of the parameter, the control unit selects a first ignition unit, for example ignition unit 205-1, as shown at step 410. In one implementation, the selection of an ignition unit is based on a predetermined logic of the control unit.

At step 408, if it is determined that the value of the selected parameter is higher than the threshold value of the parameter, at step 412 it is determined whether a single ignition unit would be sufficient for an efficient combustion. Again, based on the predetermined logic of the control unit, if found YES, the control unit selects the second ignition unit as shown at step 414 and if found NO, the control unit selects a combination of two or more ignition units as illustrated at step 416.
Upon selection of the ignition unit(s), a switching unit of the control unit fires the trigger
signal to the selected ignition unit(s), in accordance with the predetermined logic of the control
unit. In one implementation, the switching unit may be the switching unit 350. Upon receiving f
the trigger signal and the timing signal processed by an ignition controller of the ignition unit(s),
the triggered ignition unit fires a spark across a spark generation device, such as the spark plug
217. as illustrated at step 418. In another implementation, a trigger signal from the control unit
controls the ignition timing as well as the selection of the ignition units to discharge into the
spark generation device.
At step 420, it is determined whether a next combustion cycle is initiated. If found YES,
the steps 406 to 420 are repeated, else the loop is brought to a STOP and the CIS is de-actuated,
as shown at step 422. Hence, the CIS can be devised to produce a sequence of one or more
sparks across the spark plug in a single combustion cycle.
The order in which the method 400 is described is not intended to be construed as a limitation, and the steps described can be combined in other ways obvious to a person skilled in the art. Additionally, individual blocks may be added or deleted from the method without departing from the spirit and scope of the subject matter described.

The previously described versions of the subject matter and its equivalent thereof have many advantages, some of which are described below. The subject matter described herein provides a CIS having multiple ignition units for controllably generating sparks across a spark generation device. The CIS can be configured to trigger the ignition units at different instants and in different permutations to produce a plasma of desired energy and durations to suit any engine condition. The CIS produces an efficient combustion of the air-fuel mixture at all operating conditions of the engine.
Moreover, the extended spark energy and the extended duration of a spark helps in achieving an extended plasma. Also, the CIS described herein enhances the engine performance, by providing high efficiency, increased fuel economy, high reliability, accurate ignition timing, high spark energy, and low maintenance requirements. Additionally, owing to the employment of additional ignition units, the load on an individual ignition unit is reduced considerably, thereby increasing the life of the CIS system.
While certain features of the claimed subject matter have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes that fall within the true spirit of the claimed subject matter.

1. A controlled ignition system (200) for a small bore IC engine (125), said controlled
ignition system (200) comprising:
at least one spark generation device (217); and
a control unit (215) for controlling spark generation across said spark generation device
(217);
characterized in that,
said control unit (215) receives signals from a plurality of sensors (360) for sensing selected engine conditions, wherein based on said received signals and a predetermined logic of said control unit (215), said control unit (215) selectively causes one or more of a plurality of ignition units (205) to discharge into said spark generation device (217) through an ignition coil (230).
2. The controlled ignition system (200) as claimed in claim 1, wherein said control unit (215) selectively triggers one or more of said ignition units (205) upon comparing a sensed value of the selected engine condition with a threshold value of the selected engine condition.
3. The controlled ignition system (200) as claimed in claim 1, wherein said control unit (215) comprises a switching unit (350) for selectively triggering one or more of said ignition units (205).
4. The controlled ignition system (200) as claimed in claim 1, wherein said ignition units (205) comprise at least one ignition controller 210 for controlling the ignition timing of said ignition units 205.
5. fhe controlled ignition system (200) as claimed in claim 1, wherein said plurality of sensors (360) are selected from the group consisting of a pulser coil (220), a throttle position sensor, and an engine RPM sensor.

(3. The controlled ignition system (200) as claimed in claim 5, wherein said plurality of ignition units (205) discharge into said spark generation device (217), upon receiving a timing signal from said pulser coil (220) and a trigger signal from said control unit (215).
7. The controlled ignition system (200) as claimed in claim 1, wherein said plurality of
ignition units (205) are selected from the group consisting of an AC capacitor discharge
ignition unit, a DC capacitor discharge ignition unit, and an inductor discharge ignition
unit.
8. The controlled ignition system (200) as claimed in claim 1, wherein said controlled
ignition system (200) operates in a single ignition mode or a multiple ignition mode.
9. The controlled ignition system (200) as claimed in claim 8, wherein said control unit
(215) in said multiple ignition mode operates two or more of said ignition units (205)
simultaneously or sequentially.
10. The controlled ignition system (200) as claimed in claim 1, wherein said spark generation device (217) is a spark plug.
11. A vehicle (100) comprising a controlled ignition system (200) as claimed in any one of the preceding claims.
12. A vehicle (100) of claim 11, wherein said vehicle (100) comprises a magneto, said
magneto being a primary power source for said controlled ignition system (200).