JP3660664B2 - Hybrid vehicle drive apparatus and drive method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for driving a hybrid car in which a sufficient electric power is continuously stored in a battery for excellent driving characteristics. <P>SOLUTION: A controller of the hybrid car driving device has a plurality of drive modes which control an engine and a motor generator according to the open-degree of an accelerator that operates the engine and the charge rate of a battery. An engine travel power-generation mode is employed if the charge rate of the battery is low, where the engine is driven as a driving source for the car and motor generator while the electric power generated by the motor generator is collected into the battery. An acceleration mode is employed if the charge rate of the battery is high and the open-degree of the accelerator or the changing rate of the accelerator open-degree is high, where the engine and the motor generator are used for driving the car. An engine travel mode is employed if the charge rate of the battery is high and the open-degree of the accelerator is low, where only the engine is used for driving the car. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving apparatus and a driving method for a hybrid vehicle using both an engine and a motor / generator as driving sources.
[0002]
[Prior art]
Conventionally, as described in Japanese Patent Application Laid-Open No. 9-65508, there is known a hybrid vehicle that travels by driving a generator of an engine to generate electric power and driving a traveling motor with the electric power.
[0003]
[Problems to be solved by the invention]
In a conventional hybrid vehicle, fuel consumption reduction and exhaust purification are performed by switching the drive source appropriately according to the running state, for example, by starting the motor where exhaust gas becomes a problem, or by driving the motor during acceleration. In addition, stopping the engine during idling is also an effective method as an exhaust gas countermeasure.
[0004]
However, in a hybrid vehicle, there is still a problem to be solved in order to maintain sufficient driving characteristics while ensuring sufficient power for the battery and extending the travel distance.
[0005]
As an exhaust gas countermeasure, for example, when the vehicle is temporarily stopped, such as when waiting for a signal, the engine idling is stopped to reduce the exhaust amount of harmful exhaust gas. If sufficient electric power is not secured in the battery even if the engine is restarted, the engine cannot be restarted smoothly and the acceleration operation cannot be performed. Further, if the environmental conditions such as the cooling water temperature of the engine are not in an appropriate range when the vehicle is temporarily stopped, the engine may not be restarted smoothly immediately after that.
[0006]
An object of the present invention is to overcome the above-described problems and to provide a driving device and a driving method for a hybrid vehicle that is excellent in driving characteristics while ensuring sufficient power for a battery at all times.
[0007]
Another object of the present invention is to smoothly perform restart and acceleration operation after stopping idling when the engine idling is stopped at the time of temporary stop of the vehicle to reduce the exhaust amount of harmful exhaust gas as a measure against exhaust gas. It is an object of the present invention to provide a driving device and a driving method for a hybrid vehicle.
[0008]
[Means for Solving the Problems]
  To achieve the above object, the present invention provides an engine, a motor / generator coupled to the engine, a main battery connected to the motor / generator via a power converter, and the main battery.Via the switching elementConnected auxiliary battery,Depending on the charging rate of the main batteryThe engine,Motor / generatorAnd the switching elementAnd a controller for controlling the main battery,By the controllerThe controller is controlled to a voltage higher than that of the auxiliary battery and is used as a power source of an electromagnetic coil that drives an injector or an intake / exhaust valve of the engine. The controller is responsive to a driving state of the vehicle and a charging rate of the main battery. A plurality of operation modes for controlling the engine and the motor / generator, and when the charging rate of the main battery is lower than a predetermined value, the engine is driven by the vehicle and the motor / generator drive source. And the engine running power generation mode in which the electric power generated by the motor / generator is collected in the main battery, the charging rate of the main battery is higher than a predetermined value, and the opening degree of the accelerator for operating the engine is predetermined. If the value is greater than the value, the engine and the motor / generator are An engine running mode in which only the engine is operated as a vehicle driving source when the charging rate of the main battery is higher than a predetermined value and the opening degree of the accelerator is smaller than a predetermined value. It is characterized by.
[0009]
  Another feature of the present invention is that the controller has a key switch on,SaidThe accelerator is off and the vehicle speed is below a predetermined value, andMainThe battery charge rate is higher than the specified valueWhenIsSet to engine stop mode to stop the engineThere is.
[0010]
  Another feature of the present invention is that the controller, in addition to the stop condition,SaidEngine coolant temperature is predeterminedLess thanThe inclination angle of the car that is on and stopped is predeterminedLess thanIn the case ofSaidThe engine stop mode is set.
[0011]
  Other features of the present invention include an engine, a motor / generator coupled to the engine, a main battery connected to the motor / generator via a power converter, and the main battery.Via the switching elementAuxiliary battery connected and the engine according to the driving state of the car and the charging rate of the main battery,Motor / generatorAnd the switching elementA controller that controls the main battery,By the controllerWhen driving a hybrid vehicle controlled to a voltage higher than that of the auxiliary battery and used as a power source of an electromagnetic coil for driving an injector or an intake / exhaust valve of the engine, the charging rate of the main battery is lower than a predetermined value Operates in the engine running power generation mode, operates the engine as a drive source for the car and the motor / generator, collects the electric power generated by the motor / generator in the main battery, and the charging rate of the main battery exceeds a predetermined value. And when the accelerator opening degree for operating the engine is larger than a predetermined value, the engine and the motor / generator are operated as a vehicle drive source when the engine and the motor / generator are driven, and the charging rate of the main battery is higher than the predetermined value. Higher and the accelerator opening is smaller than a predetermined value. As engine travel mode is to be operated only the engine as a vehicle driving source.
[0012]
According to the present invention, it is possible to improve driving characteristics such as fuel consumption reduction and acceleration of a hybrid vehicle. In particular, even when the key switch is on, the engine idling is stopped under certain conditions when the accelerator is off. Therefore, as a measure against exhaust gas, the engine idling is stopped when the vehicle is temporarily stopped to reduce harmful exhaust gas emissions. In addition, the operation at the time of temporary stop can be simplified, and restart after the stop and acceleration operation can be performed smoothly.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a hybrid vehicle driving apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a controller that controls the engine 2, the motor / generator 3, and the like according to the driving state of the vehicle. A clutch 9 is provided between the motor / generator 3 and the transmission 10. When the automatic transmission mechanism is employed, the clutch 9 is omitted. The motor / generator 3 is supplied with electric power from the main battery 5 via the inverter 4, and the electric power generated by the motor / generator 3 is charged to the main battery 5 with a required voltage via the inverter 4. 7A is a load suitable for using a relatively high voltage as a power source, for example, an electromagnetic coil of an injector of the engine 2 or an electromagnetic valve for driving an air supply / exhaust valve.
[0014]
The rotor 31 of the motor / generator 3 is directly connected to the crankshaft 21 of the engine 2. 32 is a stator of the motor / generator 3, and 33 is a permanent magnet. The rotor 31 of the motor / generator 3 and the crankshaft 21 of the engine 2 may be connected via a power transmission mechanism such as a gear.
[0015]
Reference numeral 6 denotes an auxiliary battery that supplies power to a load 7B such as a lamp, and is connected to the main battery 5 via a switching element (eg, FET element) 8. The auxiliary battery 6 is charged from the main battery 5 by turning on and off the switching element 8 at a frequency of about 100 kHz. The voltage of the main battery 5 is controlled to a voltage lower than 60V and higher than that of the auxiliary battery 6, such as 48V or 36V. By using the main battery 5 as a power source such as an electromagnetic coil for driving the fuel injection valve of the engine 2, the responsiveness of the fuel injection valve can be increased, for example. On the other hand, the voltage of the auxiliary battery 6 is controlled to a value lower than the voltage of the main battery 5, for example, 12V or 24V.
[0016]
Since the voltage of the main battery 5 is low, an electric shock can be avoided, so that the negative (ground) line of the main battery 5 and the auxiliary battery 6 can be made common and special wiring can be omitted. However, a two-wire system in which a plus line and a minus (ground) line of the main battery 5 and the auxiliary battery 6 are individually provided as necessary may be used.
[0017]
The controller 1 controls the operation of the engine 2 and the motor / generator 3 according to the driving state of the car and the charging state of the main battery. The electric power generated by the motor / generator 3 while the vehicle is running and stored in the main battery 5 is a power source that replaces the engine or assists the engine when starting, accelerating, or when power is insufficient. Is used to drive the motor / generator 3. The obtained power may be used for lamps and other auxiliary electrical equipment. However, when the storage amount of the main battery 5 is equal to or less than a predetermined value, power is not supplied to the auxiliary machine.
[0018]
FIG. 2 shows a detailed configuration example of the controller 1. The controller 1 includes an integrated control unit 11, a motor / generator controller 12, an engine controller 13, and an auxiliary battery controller 14.
[0019]
The integrated control unit 11 has an operation mode determination processing unit, and information such as a key switch, an accelerator switch (accelerator on / off), an accelerator opening sensor, a brake switch, a vehicle speed sensor, a tilt switch, a battery voltage sensor, and the like. Entered. Based on this information, the integrated control unit 11 determines the driving mode of the vehicle, calculates the driving commands NMG *, τMG *, τNE *, VBs *, S *, and outputs each driving command to the motor / generator controller 12. , Output to the engine controller 13, auxiliary battery controller 14, and transmission 8, respectively.
[0020]
The motor / generator controller 12 generates and outputs a PWM signal for controlling the inverter 4 from the operation commands NMG *, τMG * and information on the rotation speed and current of the motor / generator 3. The motor / generator functions as an electric motor when the operation command τMG * is +, and functions as a generator when the operation command τMG * is −.
[0021]
The engine controller 13 controls the fuel injection amount, ignition timing, and opening / closing of the supply / exhaust valve based on the operation command τNe * and the engine speed N.
[0022]
The auxiliary battery controller 14 generates and outputs a PWM signal so that the voltage of the auxiliary battery coincides with the command VBs *, chopper-controls the switching element 8, and maintains the charging rate of the auxiliary battery at a predetermined value.
[0023]
FIG. 3 shows a detailed configuration example of the motor / generator controller 12. The motor / generator controller 12 includes idq detection means 124, id, iq current control means 125, 2/3 phase conversion means 121, PWM control means 122, phase calculation means 120, and speed calculation means 123. The speed calculation means 123 is connected to the encoder 15, and the phase calculation means 120 is connected to the magnetic pole position detection means 16. The motor / generator controller 12 further includes a torque command generation unit 128, an Iq control unit 127, and an Id control unit 126.
[0024]
The torque command generator 128 receives the driving finger NMG * or the target torque command τMG *. When it is desired to accurately control the rotational speed of the motor / generator to a predetermined value as in the case of engine cranking, an operation command NMG * that directly indicates the rotational speed NMG of the motor / generator is given. Further, when it is desired to generate a predetermined torque in the motor / generator as in the acceleration operation, the target torque command τM * is directly given. Further, when the motor / generator is operated as a generator, the value of the given target torque command τMG * is negative.
[0025]
When the operation command NMG * is given, the torque command calculation unit 128 calculates the torque command value τMG * based on the rotation number calculated by the speed calculation means 123 from the operation command NMG * and the pulse signal from the encoder 15. To do. Based on the torque command value τMG * or the directly given target torque command τMG *, the Iq control means 127 calculates a command value Iq * of the q-axis current corresponding to the torque component current. On the other hand, the command value Id * of the d-axis current is calculated by the Id control means 126 based on the torque command value τMG * and the rotational speed calculated by the speed calculation means 123, so that Id * that minimizes the loss is calculated. In this way, the motor / generator controller 12 calculates current command values Iq * and Id * necessary for high-efficiency control of the motor / generator 3.
[0026]
The IdIq detecting means 124 converts the three-phase / two-phase coordinates of the three-phase AC current of the motor current detected by the current detector 17 to process and calculate the d and q-axis currents Id and Iq. Based on these detected values and command values Iq * and Id *, the IdIq current control means 125 performs proportional or proportional integral current control processing to calculate voltage command values Vq * and Vd *.
[0027]
Further, the 2 / 3-phase conversion means 121 performs 2-phase / 3-phase coordinate conversion to calculate 3-phase AC voltage command values VU *, VV *, and VW *. The PWM control unit 122 compares the voltage command values VU *, VV *, and VW * with a carrier wave signal of a triangular wave signal, generates a PWM signal for the inverter 4, and drives the inverter 4. In this way, by applying a PWM-controlled voltage to the motor / generator 3, the motor current is controlled to the current command values Iq * and Id *.
[0028]
The phase angles θ1 and θ2 used in the 2/3 phase conversion process 121 and the coordinate conversion process of the IdIq detection unit 124 are magnetic poles that output a signal having the same phase as the induced voltage of the motor / generator 3 in the phase calculation unit 120. It is calculated from each output of the position detector 16 and the encoder 15 that outputs a rotation angle signal (pulse signal).
[0029]
By performing such processing, the motor / generator 3 is controlled with a torque command value τM * and high efficiency with a minimum loss.
[0030]
FIG. 4 shows a configuration example of the engine controller 13 and the engine controlled by the engine controller 13.
[0031]
Reference numeral 20 denotes a throttle valve assembly or throttle body having a throttle valve for controlling the amount of intake air. Reference numeral 21 denotes an air cleaner, and a plurality of intake branch pipes 22 supply air to each cylinder of the engine 26 at the outlet. Is connected. Reference numeral 23 denotes an electronically controlled fuel injection valve attached to the intake branch pipe 22. An intake valve 24 driven by an electromagnetic valve 25 is provided on the intake side of the engine, and an exhaust valve 29 driven by an electromagnetic valve 30 is provided on the discharge side. An O2 sensor 31 is provided in the exhaust pipe 28. The engine controller 13 receives outputs from the water temperature sensor 32, the cam angle sensor 18, the pressure sensor of the intake branch pipe 22, the throttle sensor for detecting the opening of the throttle valve, etc., and inputs the fuel injection valve 23, the ignition coil 27, A control signal is output to the ISC valve, the fuel pump 32 and the like. 31 is a fuel pump relay. Reference numeral 30 denotes a fuel chamber. The fuel is sucked out by the fuel pump 32, is adjusted by a pressure regulator through the fuel pipe 33, and reaches the fuel injection valve 23. An appropriate injection amount of the fuel injection valve 23 is determined by calculation by the engine controller 13 based on inputs from various sensors.
[0032]
The controller 13 includes a computer including an input circuit 131, an A / D conversion unit 132, a central processing unit 133, a ROM 138, a RAM 139, and an output circuit 136. The input circuit 131 receives an input signal 130 (for example, a signal from an operation command τNE *, a coolant temperature sensor, a throttle opening sensor, or the like), removes a noise component from the signal, and converts the signal into an A / D signal. The data is output to the conversion unit 132. The A / D conversion unit 132 performs A / D conversion on the signal and outputs the signal to the central processing unit 133. The central processing unit 133 is a function that performs the above-described control by taking in the A / D conversion result and executing a predetermined control program for a fuel injection control program stored in a medium such as the ROM 138 or other control. It has.
[0033]
The calculation result and the result of the A / D conversion are temporarily stored in the RAM 139, and the calculation result is output as a control output signal 137 through the output circuit 136, and the fuel injection valve 23, the ignition coil 27, and the ISC valve. And used for controlling the solenoid valves 25 and 30 and the fuel pump 32. The opening / closing timing of the solenoid valves 25 and 30 is calculated based on the output of the cam angle sensor 18.
[0034]
The electric power of the fuel injection valve 23, the electromagnetic valve 25, and the electromagnetic valve 30 is supplied from the battery 5.
[0035]
The hybrid vehicle drive device of the present invention is driven based on a predetermined operation mode as shown in FIG. That is, one of a plurality of preset driving modes is selected based on the driving state of the vehicle, for example, the accelerator opening or the transmission state, and the vehicle target torque, the vehicle speed, etc. The optimum driving source is selected from the viewpoint of reducing harmful exhaust gas and improving fuel efficiency. The target torque to be output by the vehicle drive device is obtained, for example, by calculation.
[0036]
As shown in FIG. 5, there are the following operation modes, and one of these is selected according to whether the vehicle accelerator or clutch is on or off.
[0037]
(1) Start mode 1
When the key switch is on and the starter switch is on, the motor / generator is rotated to start the engine. As an operation command, NMG * corresponding to an engine speed of 50 to 100 RPM is output. Note that τNE * = 0, VBs * = OFF, and S * = OFF. A starter motor (not shown) may be used instead of the motor / generator.
[0038]
(2) Start mode 2
After the engine is temporarily stopped with the key switch on, the engine is started by the motor / generator or starter motor with the accelerator switch on and the clutch off. The operation command NMG * is the same as in the start mode 1.
[0039]
(3) Idling mode
After the engine is started, if the key switch is on, the accelerator switch is off, and the engine stop mode is not established, the engine is idled. When the charging rate of the battery is high, NMG * corresponding to an engine idling speed of 600 to 700 rpm is output as an operation command. Note that τMG * = 0, VBs * = OFF, and S * = OFF. However, when the charging rate of the main battery is low, for example, when the battery voltage VBM is below a predetermined value, a predetermined τNE * is output (τMG *> 0), and the motor / generator is rotated to charge the main battery. Also do.
[0040]
(4) Engine running power generation mode
  When the charging rate of the main battery does not reach a predetermined value VBMH (for example, 70%), the motor / generator is used as a generator to run while charging the battery. When the accelerator opening is large (more than the target torque TA), the main battery charge rate is a predetermined value.V BML The engine running power generation mode is set below (for example, 40%). At this time, the operation command S * = ON and VBs * = ON. Further, as τMG *, a torque equivalent value for driving the motor / generator is added to an engine speed equivalent value corresponding to the accelerator opening and output. The motor / generator generates an output of 3 KW to 4 KW at 48V, for example. τNE * is a value such that the motor / generator generates a predetermined rated power.
[0041]
(5) Acceleration mode
  Battery charge rate is a predetermined valueV BML When the accelerator opening is large (the target torque TA or more), not only the engine but also the motor / generator is used as a power source for accelerating the vehicle. Set operation command S * to ON. Further, τMG * and τNE * are determined and output so that the acceleration torque corresponding to the accelerator opening is output by the engine and the motor / generator. It is desirable to set VBs * = OFF.
[0042]
(6) Engine running mode
When the battery charging rate exceeds a predetermined value (VBMH) and the accelerator opening is not large (less than the target torque TA), the engine is operated only. Set operation command S * to ON. Also, τMG * = 0, and τNE * outputs an engine speed equivalent value corresponding to the accelerator opening.
[0043]
(7) Regeneration mode
If the key switch is on, the accelerator switch is off, the vehicle speed is greater than 0, and the battery charge rate has not reached the specified value (VBMH), the motor / generator is used as a generator and the battery Drive at a reduced speed while charging. The operation command S * = ON, VBs * = ON, and τNE * = 0. τMG * is set to a negative value so that the motor / generator generates a predetermined rated power. When the brake switch is on, τMG * is increased to increase the braking force. When the charging rate of the battery is greater than or equal to a predetermined value, τMG * = 0.
[0044]
(8) Engine stop mode
When either of the following conditions (a) or (b) is satisfied, the engine is stopped.
[0045]
(A) The key switch is off.
[0046]
  (B) The key switch is on, the accelerator switch is off, the vehicle speed is 0, and the battery charging rate is equal to or higher than a predetermined value (or the battery voltage is a predetermined value).V BML Above). As a requirement, the engine cooling water temperature is not less than the predetermined value TS, the tilt angle of the stopped vehicle body is not more than the predetermined value θ, and the auxiliary equipment such as an air conditioner is switched off. May be.
[0047]
In the engine stop mode, the operation command S * = OFF, VBs * = OFF, τNE * = 0, and NMG * = 0.
[0048]
The engine stop mode is set in consideration of vehicle restart and safety. For example, if the battery voltage is low or the engine coolant temperature is low, it is difficult to start the engine when restarting after a temporary stop. Therefore, when the engine is not suitable for restarting the engine, the eye drink operation of the engine is continued for a while after the accelerator switch is turned off to charge the battery or warm the engine. In addition, when the vehicle is temporarily stopped on a slope, the engine's eye drink operation is continued to ensure the necessary torque so that the vehicle does not run under its own weight. Further, when the voltage of the auxiliary battery is not sufficient to continue the operation of auxiliary equipment such as an air conditioner, the eye drink operation is continued to secure necessary power.
[0049]
Next, FIG. 6 is a diagram showing an outline of the operation flow of the controller 1. When the key switch is on, the operation is started in the start mode 1. The start mode 1 is set as an initial setting, an operation command NMG * of the motor / generator 3 is output, and the motor / generator 3 is operated alone (steps 602 and 604). However, when the storage amount (charging rate) of the main battery 5 is equal to or less than a predetermined value, necessary measures for securing the storage amount are taken. Next, the state of an accelerator opening, a clutch, a key switch, etc. is detected. Further, the vehicle speed, the engine speed, the engine coolant temperature, the inclination sensor, and the on / off states of auxiliary devices are also detected (step 606).
[0050]
Further, the storage amount (charge rate) of the battery is obtained from the voltages of the main battery 5 and the auxiliary battery 6 (step 608).
[0051]
Then, it is determined from the detected various values whether or not the operation mode needs to be changed (step 610). If it is necessary to change the operation mode, the operation mode is changed (step 612). Next, the operation command NMG * or τMG *, NE *, VB *, S * is calculated and output based on the detected value in accordance with the set operation mode (step 614). This process is repeated until the key switch is turned off. If the key switch is turned off, operation stop processing is performed (steps 616 and 618).
[0052]
FIG. 7 shows an example of the relationship between the driving conditions during traveling and the operating states of the respective driving sources by the hybrid vehicle driving apparatus of FIG. After the key switch is turned on (T0) and activated, first, the motor / generator 3 functions as an engine cranking motor to start the engine and start fuel injection. Further, after the engine is started and the idling speed is reached (T2), the clutch 9 is turned on to transmit the driving force to the vehicle. When the battery charging rate is low during idling, the motor / generator 3 is driven as a generator to charge the battery.
[0053]
After the accelerator is in an ON state, that is, after the accelerator is depressed (T3), the engine speed increases and the vehicle speed increases according to the accelerator opening. When the battery charge rate is high and the accelerator opening, that is, the target torque is large, the acceleration mode is set, and the motor / generator 3 is driven as a motor by the electric power stored in the main battery 5 to assist the acceleration of the vehicle.
[0054]
When the battery charge rate is high, the vehicle speed exceeds SA, and the accelerator opening is relatively small (T4), the motor / generator 3 is stopped and the engine is operated only (engine operation mode).
[0055]
When the charging rate of the battery is low (T5-T6), the engine running power generation mode is set, and the motor / generator 3 is driven as a generator using the remaining power of the engine to charge the main battery and the auxiliary battery. When the battery is fully charged, the drive of the motor / generator 3 is stopped.
[0056]
After the brake is turned on and the accelerator is in the OFF state, that is, after the accelerator depression is stopped (T6), the vehicle is decelerated. When the battery charge rate is low during deceleration, the regeneration mode is set, and the motor / generator 3 functions as a generator that uses the inertia energy of the vehicle and collects power in the main battery 5. When the battery is fully charged, the drive of the motor / generator 3 is stopped.
[0057]
When the accelerator is OFF and the vehicle speed is reduced to a predetermined value, for example, zero (T7), it is determined whether the engine stop mode is established. Even if the key switch is on, if the accelerator switch is off, the vehicle speed is 0, and the battery voltage is equal to or higher than the predetermined value VBS, the engine stop mode is established, so the engine is stopped. As engine stop mode conditions, the engine coolant temperature is not less than the predetermined value TS, the tilt angle of the stopped vehicle body is not more than the predetermined value θ, and auxiliary equipment such as an air conditioner is switched off. These conditions may be added.
[0058]
If the engine stop mode is not established at (T7), the idling mode is continued and the engine rotation is continued. In the meantime, if the engine stop mode is established such as an increase in engine coolant temperature (T8), the engine is stopped.
[0059]
After the engine is stopped, if the key switch remains on and the accelerator switch is turned on again (T9), the engine is started in the start mode 2 (T10), and an acceleration operation corresponding to the accelerator opening is performed (T12). ).
[0060]
If the key switch is turned off (T13), the engine stop mode is established, so the engine is stopped.
[0061]
In this way, the hybrid vehicle drive system as a whole can be improved in fuel consumption and driving characteristics by appropriately controlling the relationship between the operating states of the driving sources based on the battery charge rate and the driving conditions during driving. However, it is possible to reduce the emission amount of harmful exhaust gas components.
[0062]
In the above example of FIG. 7, when (T6) is the deceleration in front of the traffic light and (T7) to (T9) are waiting for the signal, the engine idling is stopped during the period (T8) to (T9). The amount of harmful exhaust gas emitted can be suppressed. In addition, in the period (T7) to (T8), consideration is given to maintaining the battery voltage and the engine coolant temperature. Therefore, in (T9), the engine is smoothly operated even after idling is stopped. Can be restarted.
[0063]
Next, the auxiliary battery controller 14 includes a duty calculation unit 141 and a PWM control unit 142, as shown in FIG. The duty calculation unit 141 calculates the duty α from the command VBs * and the auxiliary battery voltage VBs which are in a predetermined relationship with the charging rate (voltage VBM) of the main battery 5. As shown in FIG. 9, the duty α decreases as the voltage VBM increases. The PWM control unit 142 generates a PWM signal corresponding to the duty α, and chopper-controls the switching element 8.
[0064]
【The invention's effect】
As described above, according to the present invention, it is possible to improve driving characteristics such as fuel consumption reduction and acceleration of a hybrid vehicle. In particular, even when the key switch is on, the engine idling is stopped under certain conditions when the accelerator is off. Therefore, as a measure against exhaust gas, the engine idling is stopped when the vehicle is temporarily stopped to reduce harmful exhaust gas emissions. In addition, the operation at the time of temporary stop can be simplified, and restart after the stop and acceleration operation can be performed smoothly.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of a hybrid vehicle drive apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a detailed configuration example of a controller in FIG. 1;
FIG. 3 is a diagram showing a detailed configuration example of the motor / generator controller of FIG. 2;
4 is a diagram showing a configuration example of an engine controller of FIG. 2 and an engine controlled by the engine controller. FIG.
FIG. 5 is a diagram showing an example of an operation mode of the hybrid vehicle drive device of the present invention.
6 is a diagram showing an outline of an operation flow of the controller in FIG. 1; FIG.
7 is a diagram showing an example of the relationship between driving conditions during driving and operating states of each driving source by the hybrid vehicle driving apparatus of FIG. 1; FIG.
8 is a diagram showing a configuration example of an auxiliary battery controller in FIG. 2;
FIG. 9 is a diagram showing a relationship between duty α, main battery voltage VBM, and auxiliary battery voltage VBs;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Controller, 2 ... Engine, 3 ... Motor / generator, 4 ... Inverter, 5 ... Main battery, 6 ... Auxiliary battery, 8 ... Switching element, 11 ... Integrated control unit, 12 ... Motor / generator controller, 13 ... Engine Controller, 14 ... Auxiliary battery controller.

Claims (6)

An engine, a motor / generator coupled to the engine, a main battery connected via a power converter to the motor / generator, and the auxiliary battery which is connected via a switching element to the main battery, the A controller that controls the engine , the motor / generator, and the switching element according to a charging rate of a main battery, and the main battery is controlled to a voltage higher than the auxiliary battery by the controller , and The controller is used as a power source of an electromagnetic coil that drives an injector or an intake / exhaust valve of the engine, and the controller controls the engine and the motor / generator according to a driving state of the vehicle and a charging rate of the main battery. Has an operation mode When the charging rate of the main battery is lower than a predetermined value, the engine is operated as a drive source for the vehicle and the motor / generator, and the engine running power generation collects the electric power generated by the motor / generator in the main battery. Mode, and when the charging rate of the main battery is higher than a predetermined value and the opening degree of the accelerator for operating the engine is higher than a predetermined value, the engine and the motor / generator are operated as acceleration sources for driving the vehicle. When the charging rate of the main battery is higher than a predetermined value and the opening degree of the accelerator is smaller than a predetermined value, the engine running mode is set so that only the engine is operated as a vehicle drive source. Hybrid vehicle drive system.   2. The hybrid vehicle drive device according to claim 1, wherein when the key switch is on, the accelerator is off, the vehicle speed is equal to or lower than a predetermined value, and the charging rate of the main battery is equal to or higher than the predetermined value, the controller A hybrid vehicle drive apparatus characterized by being in an engine stop mode for stopping the engine.   The hybrid vehicle drive device according to claim 2, wherein, in addition to the stop condition, the controller has a cooling water temperature of the engine that is equal to or higher than a predetermined value and a tilt angle of the stopped vehicle is equal to or lower than a predetermined value. A hybrid vehicle drive device characterized by being in the engine stop mode.   4. The hybrid vehicle drive device according to claim 2, wherein when the engine is started, the controller provides the motor / generator with an operation command at a predetermined rotation speed using the motor / generator as an engine cranking motor. A hybrid vehicle drive device. An engine, a motor / generator coupled to the engine, a main battery connected to the motor / generator via a power converter, an auxiliary battery connected to the main battery via a switching element , a vehicle And a controller that controls the engine , the motor / generator, and the switching element in accordance with the operating state of the main battery and the charging rate of the main battery, and the main battery is controlled to a voltage higher than the auxiliary battery by the controller. When driving a hybrid vehicle used as a power source of an electromagnetic coil for driving an injector or an intake / exhaust valve of the engine, when the charging rate of the main battery is lower than a predetermined value, the engine is set as an engine running power generation mode. Car and motor / The generator is operated as a drive source of the generator, the electric power generated by the motor / generator is collected in the main battery, the charging rate of the main battery is higher than a predetermined value, and the opening degree of the accelerator for operating the engine is a predetermined value. When the engine and the motor / generator are operated as the driving source of the vehicle, the charging rate of the main battery is higher than a predetermined value and the opening degree of the accelerator is smaller than a predetermined value. Is a driving method for a hybrid vehicle, wherein only the engine is operated as a driving source of the vehicle in an engine running mode.   6. The method for driving a hybrid vehicle according to claim 5, wherein the key switch is on, the accelerator is off, the vehicle speed is equal to or lower than a predetermined value, the battery charging rate is equal to or higher than a predetermined value, and the engine coolant temperature is equal to or higher than a predetermined value. A method for driving a hybrid vehicle, wherein the engine is stopped in an engine stop mode when an inclination angle of the vehicle body in a stopped state is equal to or less than a predetermined value.

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