Electric vehicle control device

The control device for an electric vehicle efficiently manages engine rotational positioning and battery charging to ensure quick and efficient engine startup, minimizing fuel waste and emissions by using dual motors and independent controllers.

JP7725874B2Active Publication Date: 2025-08-20MAZDA MOTOR CORP
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Patent Information

Application Number
JP2021091091
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2021-05-31
Publication Date
2025-08-20
Estimated Expiration
2041-05-31

AI Technical Summary

Technical Problem

Starting an engine in an electric vehicle with a low battery State of Charge (SOC) can result in inappropriate rotational positioning, leading to inefficient fuel ignition and prolonged engine startup times, and consuming battery power to adjust this position is undesirable.

Method used

A control device for an electric vehicle that includes a first motor for propulsion, a second motor for generating electricity, and an engine mechanically connected to the second motor, with independent controllers to manage engine startup, power generation, and stop position adjustment, ensuring accurate rotational positioning for efficient engine operation.

Benefits of technology

The solution allows for quick engine startup from an appropriate rotational position, reducing fuel consumption and emissions while optimizing battery charging, and avoids damage to engine components during positioning adjustments.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To set an engine rotation position at an appropriate position, and start an engine.SOLUTION: A control device of an electric vehicle 1 includes: a first motor (travelling motor 11) for traveling; a battery (high voltage battery 23); a second motor (power generation motor 12) for power generation; an engine (rotary engine 3); a first controller (engine ECU 25); a second controller (motor ECU 26); and a sensor (voltage / current sensor SN5). The second controller has: a start control part 263 for starting the engine by power running the second motor; a power generation control part 264 for running the second motor for generating power so as to charge the battery; and a stop position control part 265 for adjusting an engine stop position by power running the second motor following after the first controller stops the engine when SOC of the battery is increased and running of the second motor for generating power is ended.SELECTED DRAWING: Figure 1
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Description

[Technical Field]

[0001] The technology disclosed herein relates to a control device for an electric vehicle. [Background technology]

[0002] Patent Document 1 describes an electric vehicle. This electric vehicle is equipped with a generator motor and an engine that drives the generator motor. When the SOC of the battery drops, the generator motor operates in power running mode to start the engine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-52500 A Summary of the Invention [Problem to be solved by the invention]

[0004] If the engine's rotational position is not appropriate when starting the engine, the fuel supplied to the engine may not ignite or it may take a long time for the engine to start. Therefore, it is possible to adjust the engine's rotational position to an appropriate position using the motor used to start the engine before starting the engine. However, because the battery's SOC is low before starting the engine, consuming battery power to adjust the rotational position is undesirable.

[0005] The technology disclosed herein sets the rotational position of the engine to an appropriate position and starts the engine. [Means for solving the problem]

[0006] The technology disclosed herein relates to a control device for an electric vehicle. a first motor for running the vehicle mechanically connected to a drive wheel of the vehicle; a battery electrically connected to the first motor and supplying power to the first motor; a second motor for generating electricity electrically connected to the battery; an engine having a shaft mechanically connected to the second motor and generating a driving force for moving the second motor; a first controller that operates the engine; a second controller that operates the second motor; a sensor that outputs an electrical signal related to the SOC of the battery to the second controller; The second controller a start control unit that starts the engine by powering the second motor when the SOC of the battery decreases based on the electrical signal of the sensor; a power generation control unit that causes the second motor to perform a power generation operation so that the battery is charged after the engine is started; and a stop position control unit that adjusts the stop position of the engine by powering the second motor after the first controller has stopped the engine when the SOC of the battery becomes high based on the electrical signal of the sensor and the power generation operation of the second motor is terminated.

[0007] According to this configuration, the electric vehicle includes a first motor, a second motor, and an engine. The first motor is a motor for propelling the electric vehicle. The second motor is a motor for generating electricity, and generates electricity when the engine is operating. The second motor and the engine are mechanically connected, and the second motor operates as a power running motor when the engine is started.

[0008] The first controller that operates the engine and the second controller that operates the second motor are independent of each other. The second controller has a starting control unit, a power generation control unit, and a stop position control unit. When the SOC of the battery drops, the starting control unit starts the engine using the second motor. The power generation control unit operates the second motor to generate electricity. This charges the battery.

[0009] When the battery SOC becomes high, the second motor stops generating power. After the first controller stops the engine, the stop position control unit causes the second motor to operate in power running mode. This allows the stop position control unit to adjust the stop position of the engine. The next time the engine is started, the engine can be started from an appropriate rotation position. The engine starts quickly, and degradation of fuel economy and exhaust emission performance can be suppressed.

[0010] The stop position control unit also adjusts the rotational position of the engine when the engine stops operating for power generation. At this time, the battery SOC is high, so it is acceptable to consume battery power to adjust the rotational position.

[0011] the first controller and the second controller are connected to each other via a communication line; the first controller transmits the engine position information to the second controller via the communication line; The second controller receives the signal from the first controller. of the engine The stop position of the engine is adjusted based on the position information. do.

[0012] Because the engine and the second motor are mechanically connected, the relative positional relationship between the rotational position of the engine and the rotational position of the second motor is always constant. The second controller can acquire positional information of the engine and the second motor based on the engine position information from the first controller. By adjusting the engine stop position based on the position information from the first controller, the second controller can adjust the engine rotational position to an appropriate position after the engine operation has ended.

[0013] The second controller is configured to: determining a relative positional relationship between a rotational position of the engine and a rotational position of the second motor in a state in which the rotations of the engine and the second motor are stable; The second controller adjusts the stop position of the engine based on the determined relative positional relationship. . While the second motor is operating in power generation mode, the engine rotates stably. The second controller can obtain accurate engine position information from the first controller. The second controller can accurately determine the position of the stopped engine based on the engine position information obtained while the second motor is operating in power generation mode. After the engine operation has ended, the second controller can adjust the engine rotation position to an appropriate position.

[0014] The second controller may monitor the rotational position of the engine based on the determined relative positional relationship and a signal from a motor rotation sensor that outputs a signal related to the rotation of the second motor. The stop position control unit may adjust the stop position of the stopped engine so that, if the rotational position of the stopped engine deviates from an appropriate stop position at which the engine can be started completely with a small amount of fuel without degrading exhaust emission performance the next time the engine is started, the difference from the appropriate stop position is eliminated.

[0015] the engine is a rotary engine, The second controller may adjust the stop position of the rotary engine by rotating the shaft of the rotary engine in a forward rotation direction.

[0016] When a rotary engine is rotated in reverse, the edge of the side seal attached to the rotor may interfere with the opening of the intake port, potentially damaging the side seal.

[0017] The second controller rotates the shaft in the forward direction when adjusting the rotational position of the rotary engine, thereby preventing damage to the side seal. [Effects of the Invention]

[0018] As described above, the control device for an electric vehicle can start the engine by setting the rotational position of the engine to an appropriate position. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 illustrates an exemplary electric vehicle control system. [Figure 2] FIG. 2 shows an exemplary rotary engine. [Figure 3] FIG. 3 illustrates an exemplary battery management procedure. [Figure 4] FIG. 4 shows an exemplary engine control procedure. [Figure 5] FIG. 5 shows an exemplary motor control procedure. [Figure 6] FIG. 6 shows an example of interference between a side seal and an intake port of a rotary engine. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of a control device for an electric vehicle will be described with reference to the drawings. The control device for an electric vehicle described here is an example.

[0021] (Overall configuration of electric vehicle) Fig. 1 shows a control system for an electric vehicle. The electric vehicle 1 is equipped with a traction motor 11 for driving. The traction motor 11 is mechanically connected to drive wheels 14, 14 via a reducer 13. The reducer 13 reduces the output of the traction motor 11. When the output of the traction motor 11 is transmitted to the drive wheels 14, 14, the electric vehicle 1 starts to drive.

[0022] The electric vehicle 1 includes a high-voltage battery 23. The high-voltage battery 23 stores electric power for traveling. The high-voltage battery 23 is, for example, a lithium-ion battery.

[0023] The traction motor 11 is electrically connected to the high-voltage battery 23 via a first inverter 21. The traction motor 11 and the first inverter 21 are electrically connected via a harness wire shown by a dashed line in FIG. 1 , and the first inverter 21 and the high-voltage battery 23 are electrically connected via a harness wire. The traction motor 11 receives power supply from the high-voltage battery 23 to perform power running. The traction motor 11 also performs power generation operation when the electric vehicle 1 decelerates. The first inverter 21 supplies regenerative power from the traction motor 11 to the high-voltage battery 23. The high-voltage battery 23 is charged by the regenerative power from the traction motor 11.

[0024] The electric vehicle 1 is equipped with a range extender device 30. The range extender device 30 includes a generator motor 12 for generating electricity and an internal combustion engine that drives the generator motor 12. In the electric vehicle 1 illustrated here, the internal combustion engine is a rotary engine 3.

[0025] The shaft of the rotary engine 3 is mechanically connected to the generator motor 12. When the rotary engine 3 operates, the generator motor 12 operates to generate electricity. The configuration of the rotary engine 3 will be described in detail later.

[0026] The generator motor 12 is connected to the high-voltage battery 23 via a second inverter 22. The generator motor 12 and the second inverter 22 are electrically connected via a harness wire indicated by a dashed line in FIG. 1, and the second inverter 22 and the high-voltage battery 23 are electrically connected via a harness wire. The second inverter 22 supplies the power generated by the generator motor 12 to the high-voltage battery 23. The high-voltage battery 23 is charged with the power generated by the generator motor 12. As will be described later, the generator motor 12 may also be powered by receiving power from the high-voltage battery 23. The generator motor 12 also functions as a starter. The generator motor 12 applies cranking torque to the rotary engine 3 to start the rotary engine 3.

[0027] The electric vehicle 1 includes an engine ECU (Electric Control Unit) 25, a motor ECU 26, and a battery ECU 27. The engine ECU 25, the motor ECU 26, and the battery ECU 27 are each a controller based on a well-known microcomputer. Each ECU includes a central processing unit (CPU), a memory, and an I / F circuit. The CPU executes a program. The memory is configured, for example, with a RAM (Random Access Memory) or a ROM (Read Only Memory). The memory stores programs and data. The I / F circuit inputs and outputs electrical signals.

[0028] The engine ECU 25, the motor ECU 26, and the battery ECU 27 are connected to one another via a CAN (Car Area Network) communication line 28. The engine ECU 25, the motor ECU 26, and the battery ECU 27 can transmit and receive signals to and from one another via the CAN communication line 28.

[0029] The engine ECU 25 is electrically connected to the rotary engine 3 via a signal line indicated by a two-dot chain line. The engine ECU 25 controls the rotary engine 3. An eccentric angle sensor SN1 is connected to the engine ECU 25. The eccentric angle sensor SN1 outputs a signal related to the rotation of an eccentric shaft 35, which is the output shaft of the rotary engine 3. The engine ECU 25 can obtain information about the rotational position of the rotary engine 3 based on the signal from the eccentric angle sensor SN1.

[0030] The engine ECU 25 has, as functional blocks, an engine operating point setting unit 251 and an engine control unit 252. The control of the rotary engine 3 by the engine ECU 25 will be described in detail later.

[0031] The motor ECU 26 is electrically connected to the first inverter 21 and the second inverter 22 via signal lines indicated by two-dot chain lines. The motor ECU 26 controls the traction motor 11 through the first inverter 21. The motor ECU 26 controls the generator motor 12 through the second inverter 22.

[0032] An accelerator opening sensor SN2, a vehicle speed sensor SN3, and a motor rotation sensor SN4 are connected to the motor ECU 26. The accelerator opening sensor SN2 outputs a signal corresponding to the depression amount of the accelerator pedal to the motor ECU 26. The vehicle speed sensor SN3 outputs a signal corresponding to the speed of the electric vehicle 1 to the motor ECU 26.

[0033] The motor rotation sensor SN4 outputs a signal related to the rotation of the generator motor 12 to the motor ECU 26. Based on the signal from the motor rotation sensor SN4, the motor ECU 26 can determine the rotation angle of the eccentric shaft 35 of the rotary engine 3 to which the generator motor 12 is mechanically connected.

[0034] The motor rotation sensor SN4 also outputs a signal related to the rotation of the travel motor 11 to the motor ECU .

[0035] The motor ECU 26 has, as functional blocks, a generator motor control section 261 and a travel motor control section 262. The generator motor control section 261 has a start control section 263, a generator control section 264, and a stop position control section 265. Details of the control of the generator motor 12 by the generator motor control section 261 will be described later.

[0036] The traveling motor control unit 262 controls the traveling motor 11 based on signals from the accelerator opening sensor SN2, the vehicle speed sensor SN3, and the motor rotation sensor SN4, thereby causing the electric vehicle 1 to accelerate or decelerate in response to the driver's operation of the accelerator pedal.

[0037] A voltage / current sensor SN5 is connected to the battery ECU 27. The voltage / current sensor SN5 outputs signals related to the output voltage and output current of the high-voltage battery 23 to the battery ECU 27. The battery ECU 27 has, as functional blocks, an SOC calculation unit 271 and a generated power calculation unit 272. The SOC calculation unit 271 calculates the SOC (State Of Charge) of the high-voltage battery 23 based on the signal from the voltage / current sensor SN5. The generated power calculation unit 272 calculates a target amount of power generation based on the SOC of the high-voltage battery 23 when charging of the high-voltage battery 23 is required.

[0038] (Rotary engine configuration) Fig. 2 illustrates an example of the rotary engine 3. Fig. 2 illustrates an example of the internal configuration of the rotary engine 3 when viewed from the front. The front-to-rear direction of the rotary engine 3 is the axial direction of the eccentric shaft 35, and is a direction perpendicular to the plane of the paper on which Fig. 2 is drawn.

[0039] The rotary engine 3 has one rotor 34 and a rotor accommodating chamber 31. The rotor accommodating chamber 31 is formed by a rotor housing 32 and a side housing 33. The rotor housing 32 has a trochoid inner circumferential surface 321. The rotor 34 is accommodated in the rotor accommodating chamber 31. The rotor 34 has a roughly triangular shape. The rotor accommodating chamber 31 is divided by the rotor 34 into three working chambers: a first chamber 361, a second chamber 362, and a third chamber 363.

[0040] The eccentric shaft 35 is disposed to pass through the rotor accommodating chamber 31. The rotor 34 is supported so as to perform planetary rotation relative to the eccentric shaft 35. The rotor 34 rotates around the eccentric shaft 35 so that its three apexes move along the trochoid inner peripheral surface 321.

[0041] As shown enlarged in Figure 6, an apex seal 341 is attached to each apex of the rotor 34. Furthermore, substantially cylindrical corner seals 342 are provided at both front and rear ends of each apex seal 341. Furthermore, side seals 343 are provided on both front and rear side surfaces of the rotor 34. The side seals 343 connect the corner seals 342 to each other substantially parallel to the outer periphery of the rotor 34.

[0042] The apex seal 341 abuts against the trochoid inner peripheral surface 321 of the rotor housing 32. This allows the apex seal 341 to maintain airtightness in the working chamber. The side seal 343 abuts against the side housing 33. This allows the side seal 343 to maintain airtightness in the working chamber. The corner seal 342 maintains airtightness at the joint between the side seal 343 and the apex seal 341.

[0043] 2, the first chamber 361, the second chamber 362, and the third chamber 363 move around the eccentric shaft 35, and intake, compression, expansion, and exhaust strokes are performed in the first chamber 361, the second chamber 362, and the third chamber 363, respectively. The rotational force generated by this movement is output from the eccentric shaft 35.

[0044] More specifically, the rotor 34 rotates clockwise in Fig. 2. The rotor accommodating chamber 31 is divided into an upper left region, an upper right region, a lower right region, and a lower left region by a major axis Y and a minor axis Z that pass through the rotation axis X. Each working chamber generally performs an intake stroke in the upper left region, a compression stroke in the upper right region, an expansion stroke in the lower right region, and an exhaust stroke in the lower left region.

[0045] An injector 37, a first spark plug 381, and a second spark plug 382 are attached to the rotor housing 32. The injector 37 is attached to the top of the rotor housing 32. The injector 37 injects fuel into the working chamber during the intake stroke or the compression stroke.

[0046] The first spark plug 381 is attached to the right side wall of the rotor housing 32. The second spark plug 382 is also attached to the right side wall of the rotor housing 32. The second spark plug 382 is located on the leading side of the rotor 34 relative to the first spark plug 381. The first spark plug 381 and the second spark plug 382 each ignite the air-fuel mixture in the working chamber during the compression stroke.

[0047] An intake port 391 and an exhaust port 392 open to the side housing 33. The opening of the intake port 391 is located in the upper left region of the rotor accommodating chamber 31. The intake port 391 extends horizontally leftward from this opening in a substantially straight line inside the side housing 33. The opening of the intake port 391 opens and closes as the rotor 34 rotates. The intake port 391 communicates with the working chamber during the intake stroke. The intake port 391 is connected to an intake passage. A throttle valve 394 is disposed in the intake passage. The throttle valve 394 is a throttle valve that adjusts the amount of air supplied to the rotary engine 3.

[0048] The opening of the exhaust port 392 is located in the lower left region of the rotor accommodating chamber 31. The opening of the exhaust port 392 is located below the opening of the intake port 391. The exhaust port 392 extends horizontally leftward from this opening in a substantially straight line inside the side housing 33. The opening of the exhaust port 392 opens and closes as the rotor 34 rotates. The exhaust port 392 communicates with the inside of the working chamber during the exhaust stroke.

[0049] (Power generation control for electric vehicles) Next, power generation control of the electrically powered vehicle 1 will be described with reference to Figures 3 to 5. The flowchart in Figure 3 shows the procedure for managing the high-voltage battery 23 that the battery ECU 27 executes.

[0050] First, in step S51 after starting, the SOC calculation unit 271 of the battery ECU 27 calculates the SOC of the high-voltage battery 23 based on the signal of the voltage / current sensor SN5. Subsequently, in step S52, the battery ECU 27 determines whether the calculated SOC is less than the first reference SOC1. If step S52 is YES, the process proceeds to step S53. The battery ECU 27 determines that the high-voltage battery 23 needs to be charged. If step S52 is NO, the process returns to step S51.

[0051] In step S53, the battery ECU 27 calculates the decrease rate of the SOC, and in the following step S54, the power generation calculation unit 272 of the battery ECU 27 calculates the target power generation amount according to the calculated decrease rate of the SOC. The battery ECU 27 increases the target power generation amount as the decrease rate increases.

[0052] After calculating the target power generation amount, the battery ECU 27 outputs a power generation request to each of the engine ECU 25 and the motor ECU 26 via the CAN communication line 28 in step S55.

[0053] In step S56, the battery ECU 27 determines whether or not the rotary engine 3 has started, based on information from the engine ECU 25. The process repeats step S56 until the rotary engine 3 has started, and once the rotary engine 3 has started, the process proceeds to step S57.

[0054] When the rotary engine 3 starts and the generator motor 12 starts generating electricity, the SOC calculation unit 271 of the battery ECU 27 calculates the SOC of the high-voltage battery 23 in step S57. In the following step S58, the battery ECU 27 determines whether the calculated SOC exceeds the second reference SOC2. If step S58 is NO, the process returns to step S57, and the battery ECU 27 continues generating electricity. If step S58 is YES, the process proceeds to step S59. In step S59, the battery ECU 27 determines that charging of the high-voltage battery 23 has been completed, and outputs a power generation end signal to each of the engine ECU 25 and the motor ECU 26 via the CAN communication line 28.

[0055] 4 shows a control procedure for the rotary engine 3 executed by the engine ECU 25. First, in step S61 after starting, the engine ECU 25 determines whether or not there has been a power generation request from the battery ECU 27. If there has been no power generation request, the process repeats step S61, and if there has been a power generation request, the process proceeds to step S62.

[0056] In step S62, the engine ECU 25 reads the target power generation amount calculated by the battery ECU 27. In the following step S63, the engine operating point setting unit 251 of the engine ECU 25 sets the operating point of the rotary engine 3 based on the target power generation amount. In addition, in step S64, the engine control unit 252 of the engine ECU 25 sets the opening of the throttle valve 394 and the fuel injection amount so that the rotary engine 3 operates at the set operating point.

[0057] In step S65, engine start control is executed. This engine start control is executed using the generator motor 12 as a starter. Therefore, the engine start control is executed in cooperation with the engine ECU 25 and the motor ECU 26. The start control unit 263 of the motor ECU 26 powers the generator motor 12. A cranking torque is applied to the rotary engine 3.

[0058] In step S66, the engine ECU 25 determines whether or not the starting of the rotary engine 3 is complete. If the starting is not complete, the process returns to step S65, and if the starting is complete, the process proceeds to step S67.

[0059] In step S67, the engine control unit 252 of the engine ECU 25 operates the rotary engine 3 at the set operating point. In the following step S68, the engine ECU 25 determines whether or not a command to stop power generation has been issued. If a command to stop power generation has not been issued, the process returns to step S67, and the engine control unit 252 continues to operate the rotary engine 3. If a command to stop power generation has been issued, the process proceeds from step S68 to step S69. In step S69, the engine ECU 25 stops the rotary engine 3.

[0060] (Motor control during power generation) The flowchart in Figure 5 shows the control procedure for the generator motor 12 during power generation, executed by the motor ECU 26. First, in step S41 after starting, the motor ECU 26 determines whether or not power generation is in progress in response to a power generation request from the battery ECU 27. If power generation is not in progress, the process repeats step S41, and if power generation is in progress, the process proceeds to step S42.

[0061] In step S42, the power generation control unit 264 of the motor ECU 26 reads the target power generation amount calculated by the battery ECU 27, and in the following step S43, the power generation control unit 264 sets an operating point of the generator motor 12 based on the target power generation amount. In addition, in step S44, the power generation control unit 264 controls the second inverter 22 so that the generator motor 12 operates at the set operating point.

[0062] In step S45, the motor ECU 26 obtains rotational position information of the rotary engine 3 from the engine ECU 25. In step S46, the motor ECU 26 determines whether the rotation of the rotary engine 3 and the generator motor 12 is stable based on the obtained rotational position information. If the rotation is not stable, the process returns to step S45, and if the rotation is stable, the process proceeds to step S47.

[0063] In step S47, the motor ECU 26 determines the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12. Then, in step S48, the motor ECU 26 corrects the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12 based on the difference between the sampling frequency of the engine ECU 25 and the sampling frequency of the motor ECU 26 and the rotation speed of the generator motor 12. Generally, the sampling frequency of the engine ECU 25 is low and the sampling frequency of the motor ECU 26 is high. By performing a correction corresponding to the difference in sampling frequencies, the motor ECU 26 can accurately determine the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12.

[0064] In the following step S49, the motor ECU 26 corrects the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12 based on the delay time of communication via the CAN communication line 28. This allows the motor ECU 26 to determine the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12 with even greater accuracy.

[0065] Then, in step S410, the motor ECU 26 monitors the rotational position of the rotary engine 3 based on the output signal of the motor rotation sensor SN4. The rotary engine 3 and the generator motor 12 are mechanically connected, and the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12 has been determined in steps S47 to S49 described above. Therefore, the motor ECU 26 can accurately monitor the rotational position of the rotary engine 3 based on the output signal of the motor rotation sensor SN4.

[0066] In step S411, the power generation control unit 264 of the motor ECU 26 determines whether or not a command to stop power generation has been issued. While a command to stop power generation has not been issued, the process repeats step S411. The power generation motor 12 continues to generate power. If a command to stop power generation has been issued, the process proceeds to step S412. In step S412, the power generation control unit 264 stops inverter control.

[0067] In step S413, the motor ECU 26 determines whether or not the rotation of the rotary engine 3 and the generator motor 12 has stopped. The process repeats step S413 until the rotation of the rotary engine 3 and the generator motor 12 has stopped. If the rotation of the rotary engine 3 and the generator motor 12 has stopped, the process proceeds to step S414.

[0068] In step S414, the motor ECU 26 confirms the stop position of the rotary engine 3. At this time, the motor ECU 26 confirms the stop position of the rotary engine 3 based on the signal of the motor rotation sensor SN4 output while the rotary engine 3 and the generator motor 12 are stopped. As described above, the relative positional relationship between the rotational position of the rotary engine 3 and the generator motor 12 is determined while the rotary engine 3 and the generator motor 12 are rotating stably. Therefore, the motor ECU 26 can confirm the stop position of the rotary engine 3 based on the signal of the motor rotation sensor SN4. Immediately before the rotary engine 3 is stopped, the output of the eccentric angle sensor SN1 is unstable, and therefore the information on the engine rotational position output by the engine ECU 25 is low in accuracy. Because the relative positional relationship between the rotational position of the rotary engine 3 and the rotational position of the generator motor 12 is determined in advance, the motor ECU 26 can accurately determine the stop position of the rotary engine 3 based on the signal of the motor rotation sensor SN4.

[0069] In step S415, the stop position control unit 265 of the motor ECU 26 calculates the difference between the rotational position of the stopped rotary engine 3 and the appropriate stop position of the rotary engine 3. Here, the appropriate stop position of the rotary engine 3 means a stop position where the next time the rotary engine 3 is started, the rotary engine 3 can be started quickly with a small amount of fuel without degrading exhaust emission performance. In other words, if the rotational position of the stopped rotary engine 3 deviates from the appropriate stop position, the fuel injected into the working chambers will not burn, or will be discharged with almost no combustion, thereby degrading exhaust emission performance. Furthermore, the injected fuel that does not burn will be wasted, and the completion of starting the rotary engine 3 will be delayed.

[0070] In the following step S416, the stop position control unit 265 powers the generator motor 12 so as to eliminate the difference between the stop position of the rotary engine 3 and the appropriate stop position of the rotary engine 3, thereby changing the stop position of the rotary engine 3. Because the stop position of the rotary engine 3 is changed using the generator motor 12 when charging of the high-voltage battery 23 is completed, it is acceptable to consume power from the high-voltage battery 23 to adjust the stop position.

[0071] If there is no difference between the stop position of the rotary engine 3 and the appropriate stop position of the rotary engine 3, the stop position control unit 265 skips the step of changing the stop position of the rotary engine 3.

[0072] When adjusting the stop position of the rotary engine 3, the stop position control unit 265 powers the generator motor 12 so that the rotary engine 3 rotates in the forward direction. This is because if the rotary engine 3 is rotated in the reverse direction, the edge of the side seal 343 may interfere with the opening of the intake port 391, which could damage the side seal 343.

[0073] 6 illustrates an example of interference between the edge of the side seal 343 and the opening of the intake port 391. The side seal 343 is attached to the side of the rotor 34. The side seal 343 is disposed along the outer periphery of the triangular rotor 34 so as to span between the apexes of the roughly triangular rotor 34.

[0074] When the rotary engine 3 is rotating in the forward direction, the trajectory of the tip of the side seal 343 does not intersect with the edge of the opening of the intake port 391, as illustrated by the dashed-dotted arrow in the upper diagram of Figure 6. When the rotary engine 3 is rotating in the forward direction, the tip of the side seal 343 does not interfere with the opening of the intake port 391. However, when the rotary engine 3 is rotating in the reverse direction, the trajectory of the tip of the side seal 343 intersects with the edge of the opening of the intake port 391, as illustrated by the dashed-dotted arrow in the upper diagram of Figure 6. Note that the tip of the side seal 343 when the rotor 34 is rotating in the reverse direction is the opposite end to the tip of the side seal 343 when the rotor 34 is rotating in the forward direction.

[0075] The lower diagram of Figure 6 is a cross-sectional view taken along line AA of the upper diagram. As illustrated in the lower diagram of Figure 6, a groove 344 is formed in the side surface of the rotor 34. A spring 345 disposed in this groove 344 presses the side seal 343 toward the side housing 33. Therefore, when the tip of the side seal 343 overlaps the opening of the intake port 391, the tip of the side seal 343 is pressed by the spring 345 and protrudes inward of the intake port 391, that is, upward in the plane of the paper in the lower diagram of Figure 6.

[0076] Therefore, if the rotor 34 rotates in the reverse direction and the trajectory of the tip of the side seal 343 crosses the edge of the opening of the intake port 391, the protruding tip of the side seal 343 may collide with the vertical wall 393 of the opening of the intake port 391, which may damage the side seal 343.

[0077] Therefore, when adjusting the stop position of the rotary engine 3, the stop position control unit 265 of the motor ECU 26 powers the generator motor 12 so that the rotor 34 rotates in the forward direction, thereby preventing damage to the side seal 343.

[0078] Note that even when the rotor 34 is rotating in the forward direction, if the rear end of the side seal 343 overlaps with the opening of the intake port 391, it is pushed by the spring 345 and protrudes inward of the intake port 391. However, in this case, the rear end of the side seal 343 moves from left to right on the paper in the lower drawing of Figure 6, so the rear end of the side seal 343 does not collide with the edge of the opening of the intake port 391.

[0079] Note that the order of steps in each of the above-described flows is not necessarily fixed. The order of steps can be changed to the extent possible, and the processing of multiple steps can sometimes be executed simultaneously. Also, in each flow, some steps can be omitted, and new steps can be added.

[0080] 1 is an example, and systems to which the technology disclosed herein can be applied are not limited to the system shown in Fig. 1. The technology disclosed herein can be widely applied to rotary engine control systems, and the structure of the rotary engine is not limited to the structure shown in Fig. 2.

[0081] Furthermore, the electric vehicle 1 may be equipped with a reciprocating engine as the internal combustion engine. [Explanation of symbols]

[0082] 1 Electric vehicles 11. Travel motor (first motor) 12 Generator motor (second motor) 14 drive wheels 23 High Voltage Battery 25 Engine ECU (first controller) 26 Motor ECU (second controller) 263 Starting control unit 264 Power Generation Control Unit 265 Stop position control unit 28 CAN communication lines 3. Rotary engine 35 eccentric shaft SN5 Voltage / Current Sensor

Claims

1. a first motor for running the vehicle mechanically connected to a drive wheel of the vehicle; a battery electrically connected to the first motor and supplying power to the first motor; a second motor for generating electricity electrically connected to the battery; an engine having a shaft mechanically connected to the second motor and generating a driving force for moving the second motor; a first controller that operates the engine; a second controller that operates the second motor; a sensor that outputs an electrical signal related to the SOC of the battery to the second controller; The second controller a start control unit that starts the engine by powering the second motor when the SOC of the battery is reduced based on the electrical signal of the sensor; a power generation control unit that causes the second motor to perform a power generation operation so that the battery is charged after the engine is started; a stop position control unit that adjusts a stop position of the engine by powering the second motor after the first controller has stopped the engine when the SOC of the battery becomes high based on the electrical signal of the sensor and the power generation operation of the second motor is terminated, the first controller and the second controller are connected to each other via a communication line; the first controller transmits the engine position information to the second controller via the communication line; the second controller determines a relative positional relationship between a rotational position of the engine and a rotational position of the second motor based on the position information of the engine from the first controller while rotations of the engine and the second motor are stable; the second controller adjusts the stop position of the engine based on the determined relative positional relationship. Control device for electric vehicles.

2. The control device for an electric vehicle according to claim 1, the second controller monitors a rotational position of the engine based on the determined relative positional relationship and a signal from a motor rotation sensor that outputs a signal related to rotation of the second motor; Control device for electric vehicles.

3. The control device for an electric vehicle according to claim 1, When the rotational position of the stopped engine deviates from an appropriate stop position at which the engine can be started with a small amount of fuel without deteriorating exhaust emission performance the next time the engine is started, the stop position control unit adjusts the stop position of the engine so that the difference from the appropriate stop position is eliminated. Control device for electric vehicles.

4. The control device for an electric vehicle according to any one of claims 1 to 3, the engine is a rotary engine, the second controller adjusts the stop position of the rotary engine by rotating the shaft of the rotary engine in a forward rotation direction; Control device for electric vehicles.

Citation Information

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