Patent ID: 12187262

DETAILED DESCRIPTION

An embodiment of a control apparatus for an electric vehicle will hereinafter be described with reference to drawings. The control device for an electric vehicle will be described herein as an example.

(General Configuration of Electric Vehicle)

FIG.1illustrates a control system of an electric vehicle. An electric vehicle1includes a traveling motor11for traveling. The traveling motor11is mechanically connected with drive wheels14and14via a speed reducer13. The speed reducer13reduces a speed of an output of the traveling motor11. When the output of the traveling motor11is transmitted to the drive wheels14and14, the electric vehicle1travels.

The electric vehicle1includes a high-voltage battery23. The high-voltage battery23accumulates electric power for traveling. The high-voltage battery23is a lithium-ion battery, for example.

The traveling motor11is electrically connected with the high-voltage battery23via a first inverter21. The traveling motor11and the first inverter21are electrically connected together via a harness line indicated by a broken line inFIG.1, and the first inverter21and the high-voltage battery23are electrically connected together via a harness line. The traveling motor11performs power running by being supplied with electric power from the high-voltage battery23. The traveling motor11also performs electricity generation driving when the electric vehicle1decelerates. The first inverter21supplies regenerative electric power of the traveling motor11to the high-voltage battery23. The high-voltage battery23is charged by the regenerative electric power of the traveling motor11.

A range extender device30is installed in the electric vehicle1. The range extender device30includes a generator motor12for electricity generation and an internal combustion engine which drives the generator motor12. In the electric vehicle1raised here as an example, the internal combustion engine is a rotary engine3.

A shaft of the rotary engine3is mechanically connected with the generator motor12. When the rotary engine3is driven, the generator motor12performs electricity generation driving. Note that a configuration of the rotary engine3will later be described in detail.

The generator motor12is connected with the high-voltage battery23via a second inverter22. The generator motor12and the second inverter22are electrically connected together via a harness line indicated by a broken line inFIG.1, and the second inverter22and the high-voltage battery23are electrically connected together via a harness line. The second inverter22supplies electric power generated by the generator motor12to the high-voltage battery23. The high-voltage battery23is charged by the electric power generated by the generator motor12. Note that as described later, there may be a case where the generator motor12performs power running by being supplied with electric power from the high-voltage battery23. The generator motor12also functions as a starter. The generator motor12starts the rotary engine3by applying a cranking torque to the rotary engine3.

The electric vehicle1includes an engine ECU (electric control unit)25, a motor ECU26, and a battery ECU27. Each of the engine ECU25, the motor ECU26, and the battery ECU27is a controller based on a known microcomputer. Each of the ECUs includes a central processing unit (CPU), a memory, and an I/F circuit. The CPU executes programs. The memory is configured with a RAM (random access memory) and a ROM (read-only memory), for example. The memory stores programs and data. The I/F circuit inputs and outputs electric signals.

The engine ECU25, the motor ECU26, and the battery ECU27are connected with each other via a CAN (car area network) communication line28. The engine ECU25, the motor ECU26, and the battery ECU27can mutually transmit and receive signals via the CAN communication line28.

The engine ECU25is electrically connected with the rotary engine3via a signal line indicated by a two-dot chain line. The engine ECU25controls the rotary engine3. An eccentric-shaft angle sensor SN1is connected with the engine ECU25. The eccentric-shaft angle sensor SN1outputs a signal related to rotation of an eccentric shaft35as an output shaft of the rotary engine3. The engine ECU25can acquire information about a revolution position of the rotary engine3based on the signal of the eccentric-shaft angle sensor SN1.

The engine ECU25has, as function blocks, an engine operating point setting unit251and an engine control unit252. Details of control of the rotary engine3by the engine ECU25will be described later.

The motor ECU26is electrically connected with the first inverter21and the second inverter22via signal lines indicated by two-dot chain lines. The motor ECU26controls the traveling motor11through the first inverter21. The motor ECU26controls the generator motor12through the second inverter22.

An accelerator opening sensor SN2, a vehicle speed sensor SN3, and a motor rotation sensor SN4are connected with the motor ECU26. The accelerator opening sensor SN2outputs a signal corresponding to a depression amount of an accelerator pedal to the motor ECU26. The vehicle speed sensor SN3outputs a signal corresponding to a speed of the electric vehicle1to the motor ECU26.

The motor rotation sensor SN4outputs a signal related to rotation of the generator motor12to the motor ECU26. The motor ECU26can recognize a rotation angle of the eccentric shaft35of the rotary engine3, with which the generator motor12is mechanically connected, based on the signal of the motor rotation sensor SN4.

The motor rotation sensor SN4also outputs signals related to rotations of the traveling motor11to the motor ECU26.

The motor ECU26has, as function blocks, a generator motor control unit261and a traveling motor control unit262. The generator motor control unit261has a start control unit263, an electricity generation control unit264, and a stop position control unit265. Details of control of the generator motor12by the generator motor control unit261will be described later.

The traveling motor control unit262controls the traveling motor11based on the signals of the accelerator opening sensor SN2, the vehicle speed sensor SN3, and the motor rotation sensor SN4. Accordingly, the electric vehicle performs acceleration or deceleration corresponding to a manipulation of the accelerator pedal by a driver.

A voltage-current sensor SN5is connected with the battery ECU27. The voltage-current sensor SN5outputs a signal related to an output voltage and an output current of the high-voltage battery23to the battery ECU27. The battery ECU27has, as function blocks, an SOC calculation unit271and a generated electric power calculation unit272. The SOC calculation unit271calculates an SOC (state of charge) of the high-voltage battery23based on the signal from the voltage-current sensor SN5. In a case where charging for the high-voltage battery23is necessary, the generated electric power calculation unit272calculates a target electricity generation amount based on the SOC of the high-voltage battery23.

(Configuration of Rotary Engine)

FIG.2illustrates the rotary engine3as an example.FIG.2illustrates, as an example, an internal configuration of the rotary engine3as seen from front. A front-rear direction of the rotary engine3corresponds to an axial direction of the eccentric shaft35and a direction orthogonal to the page ofFIG.2.

The rotary engine3has one rotor34and a rotor housing chamber31. The rotor housing chamber31is formed with a rotor housing32and a side housing33. The rotor housing32has a trochoidal inner peripheral surface321. The rotor34is housed in the rotor housing chamber31. The rotor34has a nearly triangular shape. The rotor housing chamber31is demarcated into three operation chambers of a first chamber361, a second chamber362, and a third chamber363.

The eccentric shaft35is provided to pass through the rotor housing chamber31. The rotor34is supported to perform planetary revolution motion with respect to the eccentric shaft35. The rotor34revolves around the eccentric shaft35such that three top portions move along the trochoidal inner peripheral surface321.

As illustrated inFIG.6while being enlarged, an apex seal341is mounted on each of the top portions of the rotor34. Further, generally circular columnar corner seals342are provided to both of front-rear end portions of each of the apex seals341. In addition, side seals343are provided to both of front-rear side surfaces of the rotor34. The side seals343couple the corner seals342with each other in parallel with an outer peripheral edge of the rotor34.

The apex seal341abuts the trochoidal inner peripheral surface321of the rotor housing32. Accordingly, the apex seal341keeps airtightness of the operation chamber. The side seal343abuts the side housing33. Accordingly, the side seal343keeps airtightness of the operation chamber. The corner seals342keep airtightness of a joined portion between the side seals343and the apex seal341.

In response to revolution of the rotor34which is indicated by an arrow inFIG.2, the first chamber361, the second chamber362, and the third chamber363are displaced around the eccentric shaft35, and strokes of intake, compression, expansion, and exhaust are performed in each of the first chamber361, the second chamber362, and the third chamber363. A rotational force produced by this is output from the eccentric shaft35.

More specifically, the rotor34revolves in a clockwise direction inFIG.2. The rotor housing chamber31can be divided into a left-upper region, a right-upper region, a right-lower region, and a left-lower region by a major axis Y and a minor axis Z which pass through a rotation axis X. Each of the operation chambers mostly performs an intake stroke in the left-upper region, mostly performs a compression stroke in the right-upper region, mostly performs an expansion stroke in the right-lower region, and mostly performs an exhaust stroke in the left-lower region.

An injector37, a first spark plug381, and a second spark plug382are mounted on the rotor housing32. The injector37is mounted on a top portion of the rotor housing32. The injector37injects fuel into the operation chamber in the intake stroke or in the compression stroke.

The first spark plug381is mounted on a right side wall portion of the rotor housing32. The second spark plug382is also mounted on the right side wall portion of the rotor housing32. The second spark plug382is positioned on an advancing side of the rotor34relative to the first spark plug381. Each of the first spark plug381and the second spark plug382ignites air-fuel mixture in the operation chamber in the compression stroke.

In the side housing33, an intake port391and an exhaust port392open. An opening of the intake port391is positioned in the left-upper region of the rotor housing chamber31. The intake port391generally linearly extends, in an internal portion of the side housing33, from this opening toward a left side in a horizontal direction. The opening of the intake port391opens and closes in response to revolution of the rotor34. The intake port391communicates with the operation chamber in the intake stroke. The intake port391is connected with an intake passage. A throttle valve394is disposed in the intake passage. The throttle valve394is a throttling valve which adjusts an air amount to be supplied to the rotary engine3.

An opening of the exhaust port392is positioned in the left-lower region of the rotor housing chamber31. The opening of the exhaust port392is positioned below the opening of the intake port391. The exhaust port392generally linearly extends, in an internal portion of the side housing33, from this opening toward a left side in the horizontal direction. The opening of the exhaust port392opens and closes in response to revolution of the rotor34. The exhaust port392communicates with the operation chamber in the exhaust stroke.

(Electricity Generation Control in Electric Vehicle)

Next, electricity generation control in the electric vehicle1will be described with reference toFIGS.3to5. The flowchart inFIG.3illustrates a management procedure of the high-voltage battery23which is executed by the battery ECU27.

First, in step S51after a start, the SOC calculation unit271of the battery ECU27calculates the SOC of the high-voltage battery23based on the signal from the voltage-current sensor SN5. In next step S52, the battery ECU27determines whether or not the calculated SOC is less than a first reference SOC1. In a case where the determination in step S52is YES, the process progresses to S53. The battery ECU27determines that charging for the high-voltage battery23is necessary. In a case where the determination in step S52is NO, the process returns to S51.

In step S53, the battery ECU27calculates a decreasing rate of the SOC, and in next step S54, the generated electric power calculation unit272of the battery ECU27calculates a target electricity generation amount in accordance with the calculated decreasing rate of the SOC. The battery ECU27makes the target electricity generation amount larger as the decreasing rate is higher.

When the target electricity generation amount is calculated, in step S55, the battery ECU27outputs an electricity generation request to each of the engine ECU25and the motor ECU26through the CAN communication line28.

In step S56, the battery ECU27determines whether or not the rotary engine3is started based on information from the engine ECU25. Until a start of the rotary engine3is completed, step S56is repeated in the process, and when the start of the rotary engine3is completed, the process progresses to step S57.

When the rotary engine3is started and electricity generation by the generator motor12is started, in step S57, the SOC calculation unit271of the battery ECU27calculates the SOC of the high-voltage battery23. In next step S58, the battery ECU27determines whether or not the calculated SOC exceeds a second reference SOC2. In a case where the determination in step S58is NO, the process returns to S57, and the battery ECU27causes electricity generation to be continued. In a case where the determination in step S58is YES, the process progresses to S59. In step S59, the battery ECU27assumes that charging for the high-voltage battery23is completed and outputs an end of electricity generation to each of the engine ECU25and the motor ECU26through the CAN communication line28.

FIG.4illustrates a control procedure of the rotary engine3which is executed by the engine ECU25. First, in step S61after a start, the engine ECU25determines whether or not the electricity generation request from the battery ECU27is made. In a case where the electricity generation request is not made, step S61is repeated in the process, but in a case where the electricity generation request is made, the process progresses to S62.

In step S62, the engine ECU25reads the target electricity generation amount calculated by the battery ECU27, and in next step S63, the engine operating point setting unit251of the engine ECU25sets an operating point of the rotary engine3based on the target electricity generation amount. Further, in step S64, the engine control unit252of the engine ECU25sets an opening of the throttle valve394and a fuel injection amount such that the rotary engine3is driven at the set operating point.

In step S65, engine start control is executed. This engine start control is executed by using the generator motor12as a starter. Consequently, the engine start control is executed by cooperation between the engine ECU25and the motor ECU26. The start control unit263of the motor ECU26causes the generator motor12to perform power running. A cranking torque is applied to the rotary engine3.

In step S66, the engine ECU25determines whether or not a start of the rotary engine3is completed. In a case where the start is not completed, the process returns to step S65, but in a case where the start is completed, the process progresses to S67.

In step S67, the engine control unit252of the engine ECU25causes the rotary engine3to be driven at the set operating point. In next step S68, the engine ECU25determines whether or not an instruction to stop electricity generation is made. While no instruction to stop electricity generation is made, the process returns to step S67, and the engine control unit252continues driving of the rotary engine3. When the instruction to stop electricity generation is made, the process progresses from step S68to step S69. In step S69, the engine ECU25stops the rotary engine3.

(Motor Control in Electricity Generation)

The flowchart inFIG.5illustrates a control procedure of the generator motor12in electricity generation, the control procedure being executed by the motor ECU26. First, in step S41after a start, the motor ECU26determines whether or not electricity generation by the electricity generation request from the battery ECU27is being performed. In a case where electricity generation is not being performed, step S41is repeated in the process, but in a case where electricity generation is being performed, the process progresses to S42.

In step S42, the electricity generation control unit264of the motor ECU26reads the target electricity generation amount calculated by the battery ECU27, and in next step S43, the electricity generation control unit264sets an operating point of the generator motor12based on the target electricity generation amount. Further, in step S44, the electricity generation control unit264controls the second inverter22such that the generator motor12acts at the set operating point.

In step S45, the motor ECU26obtains revolution position information of the rotary engine3from the engine ECU25. In step S46, the motor ECU26determines whether or not the revolution of the rotary engine3and the rotation of the generator motor12are stable based on the obtained revolution position information. In a case where the revolution and rotation are not stable, the process returns to step S45, but in a case where the revolution and rotation are stable, the process progresses to S47.

In step S47, the motor ECU26confirms the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12. Then, in step S48, the motor ECU26corrects the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12based on the difference between a sampling frequency of the engine ECU25and a sampling frequency of the motor ECU26and on the rotation speed of the generator motor12. In general, the sampling frequency of the engine ECU25is low, and the sampling frequency of the motor ECU is high. The correction corresponding to the difference in the sampling frequency is performed, and the motor ECU26can thereby precisely confirm the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12.

In next step S49, the motor ECU26corrects the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12based on a delay time in communication through the CAN communication line28. Accordingly, the motor ECU26can further precisely confirm the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12.

Then, in step S410, the motor ECU26monitors the revolution position of the rotary engine3based on an output signal of the motor rotation sensor SN4. The rotary engine3and the generator motor12are mechanically connected together, and the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12is confirmed in the above-described steps S47to S49. Thus, the motor ECU26can precisely monitor the revolution position of the rotary engine3based on the output signal of the motor rotation sensor SN4.

In step S411, the electricity generation control unit264of the motor ECU26determines whether or not an instruction to stop electricity generation is made. While no instruction to stop electricity generation is made, step S411is repeated in the process. The generator motor12continues electricity generation driving. When the instruction to stop electricity generation is made, the process progresses to step S412. In step S412, the electricity generation control unit264stops inverter control.

In step S413, the motor ECU26determines whether or not the revolution of the rotary engine3and the rotation of the generator motor12are stopped. Until the revolution of the rotary engine3and the rotation of the generator motor12are stopped, step S413is repeated in the process. When the revolution of the rotary engine3and the rotation of the generator motor12are stopped, the process transits to step S414.

In step S414, the motor ECU26checks a stop position of the rotary engine3. At this point, the motor ECU26checks the stop position of the rotary engine3based on the signal of the motor rotation sensor SN4, which is output while the rotary engine3and the generator motor12reach stops. As described above, because the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12is confirmed while the rotary engine3stably revolves and the generator motor12stably rotates, the motor ECU26can check the stop position of the rotary engine3based on the signal of the motor rotation sensor SN4. Because an output of the eccentric-shaft angle sensor SN1is not stable immediately before the rotary engine3stops, precision of information of the revolution position of the engine is low, the information being output by the engine ECU25. The relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12is confirmed in advance, and the motor ECU26can thereby accurately recognize the stop position of the rotary engine3based on the signal of the motor rotation sensor SN4.

In step S415, the stop position control unit265of the motor ECU26calculates the difference between the revolution position of the stopped rotary engine3and a proper stop position of the rotary engine3. Here, a proper stop position of the rotary engine3means such a stop position that when the rotary engine3is started in the next time, exhaust emission performance is not lowered and the rotary engine3quickly completes a start with a small amount of fuel. In other words, when the revolution position of the stopped rotary engine3is deviated from a proper stop position, fuel injected into the operation chamber is not combusted or is discharged while being hardly combusted, and due to that, the exhaust emission performance is lowered. Further, for the amount of fuel which is not combusted, fuel is wasted, and completion of a start of the rotary engine3is delayed.

In next step S416, the stop position control unit265causes the generator motor12to perform power running such that the difference between the stop position of the rotary engine3and a proper stop position of the rotary engine3is removed and thereby changes the stop position of the rotary engine3. Because the stop position of the rotary engine3is changed by the generator motor12at a timing when charging for the high-voltage battery23is completed, consuming electric power of the high-voltage battery23for adjustment of the stop position is permitted.

Note that in a case where no difference is present between the stop position of the rotary engine3and a proper stop position of the rotary engine3, the stop position control unit265skips changing steps of the stop position of the rotary engine3.

In adjustment of the stop position of the rotary engine3, the stop position control unit265causes the generator motor12to perform power running such that the rotary engine3revolves in a direction of forward revolution. This is because when the rotary engine3is revolved in a direction of backward revolution, the side seal343might be damaged due to interference between an end of the side seal343and the opening of the intake port391.

FIG.6illustrates, as an example, an interference state between the end of the side seal343and the opening of the intake port391. The side seal343is mounted on the side surface of the rotor34. The side seal343is disposed along the outer peripheral edge of the triangular rotor34to be bridged from the top portion to the top portion of the nearly triangular rotor34.

A locus of a distal end of the side seal343in a case where the rotary engine3performs forward revolution does not become a locus which intersects with an edge of the opening of the intake port391, as indicated as an example by an arrow of a two-dot chain line in the upper part ofFIG.6. In a case where the rotary engine3performs forward revolution, the distal end of the side seal343does not interfere with the opening of the intake port391. However, the locus of the distal end of the side seal343in a case where the rotary engine3performs backward revolution becomes a locus which intersects with the edge of the opening of the intake port391, as indicated as an example by an arrow of a one-dot chain line in the upper part ofFIG.6. Note that the distal end of the side seal343in a case where the rotor34performs backward revolution corresponds to an end on the opposite side to the distal end of the side seal343in a case where forward revolution is performed.

The lower part ofFIG.6is a cross-sectional view taken along line A-A in the upper part. As illustrated as an example in the lower part ofFIG.6, a groove344is formed in the side surface of the rotor34. A spring345disposed in this groove344pushes the side seal343toward the side housing33. Thus, when the distal end of the side seal343overlaps with the opening of the intake port391, the distal end of the side seal343is pushed by the spring345and thereby protrudes toward an inner side of the intake port391, in other words, upward in the page in the lower part ofFIG.6.

Thus, when the locus of the distal end of the side seal343intersects with the edge of the opening of the intake port391due to backward revolution of the rotor34, the protruded distal end of the side seal343collides with a vertical wall393of the opening of the intake port391, and the side seal343might be damaged.

Accordingly, in a case where the stop position of the rotary engine3is adjusted, the stop position control unit265of the motor ECU26causes the generator motor12to perform power running such that the rotor34revolves in the direction of forward revolution. Accordingly, damage to the side seal343is avoided.

Note that even in a case where the rotor34performs forward revolution, when a back end of the side seal343overlaps with the opening of the intake port391, the back end is pushed by the spring345and thereby protrudes toward the inner side of the intake port391. However, in this case, because the back end of the side seal343moves from left to right in the page of the lower part of theFIG.6, the back end of the side seal343does not collide with the edge of the opening of the intake port391.

(Modification of Motor Control)

In the flow inFIG.5, adjustment of the stop position of the rotary engine3is performed at a timing when charging for the high-voltage battery23is completed. Adjustment of the stop position of the rotary engine3may be performed immediately before the rotary engine3is started in the next time, for example. The left flow inFIG.7illustrates a part of a procedure of motor control in electricity generation by the motor ECU26. The right flow inFIG.7illustrates a part of a procedure of engine control by the engine ECU25.

First, the motor ECU26executes control of the generator motor12in accordance with steps S41to S410inFIG.5. In other words, the generator motor12is caused to perform electricity generation driving accompanying driving of the rotary engine3, while the rotary engine3stably revolves and the generator motor12stably rotates, the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12is in advance confirmed. The motor ECU26monitors the revolution position of the rotary engine3based on the output signal of the motor rotation sensor SN4.

In step S71, the motor ECU26determines whether or not an instruction to stop electricity generation is made. While no instruction to stop electricity generation is made, step S71is repeated in the process. The generator motor12continues electricity generation driving. When the instruction to stop electricity generation is made, the process progresses to step S72. In step S72, the motor ECU26stops inverter control.

In step S73, the motor ECU26determines whether or not the revolution of the rotary engine3and the rotation of the generator motor12are stopped. Until the revolution of the rotary engine3and the rotation of the generator motor12are stopped, step S73is repeated in the process. When the revolution of the rotary engine3and the rotation of the generator motor12are stopped, the process transits to step S74.

In step S74, the motor ECU26checks the stop position of the rotary engine3. As described above, the motor ECU26checks the stop position of the rotary engine3based on the signal of the motor rotation sensor SN4, which is output while the rotary engine3and the generator motor12reach stops. Based on the relative position relationship between the revolution position of the rotary engine3and the rotation position of the generator motor12, which is in advance confirmed, the motor ECU26can accurately recognize the stop position of the rotary engine3.

In step S75, the motor ECU26calculates the difference between the stop position of the rotary engine3and a proper stop position of the rotary engine3. Then, the motor ECU26stores the difference without adjusting the stop position of the rotary engine3.

In the right flow inFIG.7, first, in step S711after a start, the engine ECU25determines whether or not an electricity generation request from the battery ECU27is made. In a case where the electricity generation request is not made, step S711is repeated in the process, but in a case where the electricity generation request is made, the process progresses to S712to start the rotary engine3.

In step S712, the motor ECU26reads out the difference, which is stored in step S75, between the stop position of the rotary engine3and a proper stop position of the rotary engine3. Then, in step S713, the stop position control unit265of the motor ECU26adjusts the stop position by using the generator motor12such that the stop position of the rotary engine3becomes a proper stop position. In this case, the stop position control unit265causes the rotary engine3to revolve in the direction of forward revolution and thereby adjusts the stop position.

After the stop position of the rotary engine3is adjusted, in step S714, the engine ECU25reads the target electricity generation amount calculated by the battery ECU27, and in next step S715, the engine operating point setting unit251of the engine ECU25sets an operating point of the rotary engine3based on the target electricity generation amount. Further, in step S716, the engine control unit252of the engine ECU25sets an opening of the throttle valve394and a fuel injection amount such that the rotary engine3is driven at the set operating point.

In step S717, the engine start control is executed. This engine start control is executed by using the generator motor12as a starter and by cooperation between the engine ECU25and the motor ECU26. Subsequently, the flow transits to step S66inFIG.4.

Note that in step S75, the motor ECU26may store the stop position of the rotary engine3, and in step S712, the motor ECU may read out the stored stop position of the rotary engine3and may thereby calculate the difference between the read-out stop position and a proper stop position of the rotary engine3.

In each of the above-described flows, order of steps is not necessarily defined. In the possible range, order of steps can be altered, and processes of plural steps can simultaneously be executed. Further, in each of the flows, a part of steps can be omitted, and steps can also be added.

Further, the systems illustrated inFIG.1are examples, and a system to which the technique disclosed herein is applicable is not limited to the systems inFIG.1. Further, the technique disclosed herein is capable of being widely applied to a control system of a rotary engine, and a structure of a rotary engine is not limited to the structure inFIG.2.

Further, a reciprocating engine as an internal combustion engine may be installed in the electric vehicle1.