JPH07250403A - Controller for electric vehicle - Google Patents

Abstract

PURPOSE:To operate a motor constantly in a high efficiency region by controlling the driving of two motors depending on the magnitude of load and to prolong the run distance of an electric vehicle between charging operations by enhancing the efficiency over the entire operational region, i.e., from light load to heavy load. CONSTITUTION:The controller for an electric vehicle comprises a first motor P2 interlocked with a wheel P1, a second motor P5 coupled mechanically with the output shaft P3 of the first motor P2 through a clutch means P4, means P6 for determining the magnitude of load, and a control means P7 for driving the first motor P2 in the case of a light load and driving the first and second motors P2, P5 in the case of heavy load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle controller for driving and controlling right and left wheels by a three-phase AC cage electric motor (so-called motor).

[0002]

2. Description of the Related Art Conventionally, as a control device for the electric vehicle (electric vehicle) of the above-mentioned example, there is a device described in Japanese Patent Application Laid-Open No. 5-115108.

That is, the left and right wheels are connected to a differential device via a drive shaft, the differential device is linked to each output shaft of two motors via a speed reducer, and the required torque for these two motors is detected. Required torque detecting means, torque distribution amount setting means for setting the distribution amount of the required torque to the two motors according to the detected required torque amount, and so that the output torque of the two motors becomes the set distribution amount. Is a control device for an electric vehicle configured to improve driving efficiency of the motor at low speed and light load, and a drive control means for driving and controlling two motors.

However, in this conventional device, the above-mentioned 2
Since the output shafts of one motor are made to face each other and the outputs of the two motors are combined into one output shaft, the two motors are simultaneously driven and controlled in the entire operating range from low load to high load. There was a problem that we could not expect a sufficient improvement in efficiency.

That is, the electric motor itself, such as the three-phase AC squirrel-cage electric motor constituting the above-mentioned motor, has a high efficiency (motor efficiency) as shown in FIG. 7 in a region where the applied load is large (high load region). ) Is exhibited, but in the area where the applied load is small (light load area), the efficiency is inferior as shown in FIG. Such an essential problem cannot be solved, and there is a problem that the efficiency during steady running shown by hatching in the figure becomes low.

On the other hand, as a conventional apparatus for effectively utilizing regenerative energy as electric energy for driving an electric vehicle, there is, for example, an apparatus described in Japanese Patent Laid-Open No. 4-355604.

That is, the vehicle braking device is provided with a power generation means for generating power when the vehicle is being braked (when braking), and the battery is charged with the generated power generated by the regenerative energy when the battery voltage is equal to or lower than a predetermined voltage. The device is configured to consume generated power by using a predetermined impedance element when the battery voltage exceeds the predetermined voltage.

However, in order to convert regenerative energy during deceleration or traveling downhill into electric energy and store it in the above-mentioned battery, it is necessary to perform rapid charging with a large current, and such rapid charging is performed. Since the heat generation of the battery deteriorates the charging efficiency and shortens the battery life, it is impossible to recover all the regenerative energy. At present, the energy storage efficiency in the battery is only about 30%. .

Further, as a conventional device for recovering the deceleration energy of the vehicle as the rotational energy of the flywheel and reproducing the recovered energy at the time of acceleration, there is, for example, the device disclosed in Japanese Patent Laid-Open No. 62-106171. .

That is, in a vehicle equipped with an engine, a CVT (Continuously Variable Tr) for transmitting rotation between the drive shaft for transmitting the engine output to the wheels and the flywheel for energy recovery by continuously changing the rotation therebetween.
ansmission, a continuously variable transmission) is provided, deceleration energy from the wheels is accumulated as rotation energy in the flywheel via the above CVT when the vehicle decelerates, and the above CTV gear ratio is controlled during acceleration transition. Then, the rotational energy accumulated in the flywheel is transmitted to the wheel to be effectively used as acceleration energy.

However, the above-mentioned CVT has a problem that it is not suitable for mounting on an electric vehicle because it is expensive, has a large mass, and is heavy.

[0012]

The invention according to claim 1 of the present invention always controls the efficiency by controlling the driving of the two motors according to the magnitude of the load (hereinafter simply referred to as efficiency, which is simply referred to as efficiency). It is an object of the present invention to provide a control device for an electric vehicle that allows the motor to be used in a high operating range, improves efficiency in the entire operating range, and extends the mileage per charge.

The invention according to claim 2 of the present invention has the object of the invention according to claim 1 as well as regenerative (regenerative).
braking), the regenerative energy of the first motor is stored as the rotational energy of the second motor, and the first motor is driven by the rotational energy stored in the second motor during the transition from the regenerative time to the non-regenerative time. High efficiency (specifically about 8
It is an object of the present invention to provide an electric vehicle control device capable of storing regenerative energy at 5%).

In addition to the object of the invention described in claim 2, the invention according to claim 3 of the present invention comprises respective drive control means (specifically, drive control means for controlling the rotation speeds of the first and second motors). By providing an inverter), the existing inverter (frequency conversion means) can be effectively used to easily control the rotation speed of each motor, particularly the second motor, without using a CVT as a heavy object. It is intended to provide a vehicle control device.

According to a fourth aspect of the present invention, in addition to the object of the third aspect of the present invention, when the acceleration demand is small at the time of re-acceleration when transitioning from regeneration to non-regeneration,
An object of the present invention is to provide a control device for an electric vehicle capable of ensuring traveling performance in response to an acceleration request by converting rotational energy accumulated in a motor into drive energy for a first motor.

According to the invention of claim 5 of the present invention, in addition to the object of the invention of claim 3, when the acceleration demand is large at the time of re-acceleration at the time of transition from regeneration to non-regeneration,
Prohibiting conversion of the rotational energy accumulated in the motor into drive energy for the first motor, and driving both the first and second motors together with the battery power supply, is sufficient to handle large acceleration demands. It is an object of the present invention to provide a control device for an electric vehicle, which can ensure excellent running performance.

The invention according to claim 6 of the present invention, in addition to the object of the invention according to claim 2, 3, 4 or 5,
When the battery charge amount is less than or equal to a predetermined value (for example, when not fully charged), a part of the regenerative energy of the first motor is accumulated as the rotational energy of the second motor, and the other part of the regenerative energy of the first motor is stored in the battery. It is an object of the present invention to provide a control device for an electric vehicle that can store the above-mentioned regenerative energy with higher efficiency by charging the electric vehicle.

According to a seventh aspect of the present invention, in addition to the object of the fourth or fifth aspect of the invention, an electric vehicle control device capable of accurately detecting an acceleration request using an existing device. For the purpose of providing.

In addition to the object of the invention described in claim 2, the invention described in claim 8 of the present invention acts as a flywheel by setting the inertial force of the second motor to be large (mass is large). An object of the present invention is to provide a control device for an electric vehicle capable of improving the rotational energy storage rate of the second motor (acting as a means for storing kinetic energy).

According to a ninth aspect of the present invention, in addition to the object of the eighth aspect of the invention, by setting the outer diameter of the rotor of the second motor to a large value, the length of the second motor can be increased. It is an object of the present invention to provide an electric vehicle control device capable of improving the rotational energy storage rate of the second motor while suppressing the above.

According to a tenth aspect of the present invention, in addition to the object of the eighth aspect of the invention, the outer diameter of the second motor is set by setting the total length of the rotor of the second motor to be large. It is an object of the present invention to provide an electric vehicle control device capable of improving the rotational energy storage rate of the second motor while suppressing the above.

[0022]

According to a first aspect of the present invention, a first motor interlocked with a wheel and an output shaft of the first motor are mechanically connected to each other via a connecting / disconnecting means. The second motor, load determining means for determining the magnitude of the load, and the first determination when the load is light based on the output of the load determining means.
It is characterized in that it is an electric vehicle control device provided with a control means for driving a motor and driving both the first and second motors when the load is high.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, a first motor that is interlocked with the wheels to generate regenerative energy in a predetermined operating range, and the first motor are provided. A second motor to which the regenerative energy of the motor is supplied, a first energy converting means for converting and controlling the regenerative energy of the first motor into the rotational energy of the second motor at the time of regeneration, and at the time of transition from regeneration to non-regeneration. A control device for an electric vehicle comprising: a second energy conversion means for converting and controlling the rotational energy of the second motor into the drive energy of the first motor.

According to a third aspect of the present invention, in addition to the configuration of the second aspect of the invention, the first and second aspects are combined.
The energy conversion means of the first and second drive control means for driving and controlling the rotation speeds of the first and second motors respectively,
It is a control device for an electric vehicle, comprising: a supply path for supplying the power generation energy when the first motor is regenerated to the second drive control means.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect of the present invention, acceleration determining means for determining the magnitude of the re-acceleration request for transition from regeneration to non-regeneration is provided, and the acceleration is performed. When the determination means detects that the acceleration request is small, the second energy conversion means performs the second energy conversion.
It is a control device for an electric vehicle that converts rotational energy of a motor into drive energy of the first motor.

According to a fifth aspect of the present invention, in addition to the configuration of the third aspect of the invention, the first and second aspects are combined.
A battery for accumulating energy for driving each motor is provided, and when the acceleration request is detected by the acceleration determining means for determining the magnitude of the acceleration request at the time of transition from regeneration to non-regeneration, the second energy conversion is performed. It is a control device for an electric vehicle that prohibits energy conversion control by means, connects the first and second motors by the connecting and disconnecting means, and drives both motors with a battery power source.

The invention according to claim 6 of the present invention, in addition to the constitution of the invention according to claim 2, 3, 4 or 5,
A charge determination unit that determines the magnitude of the charge amount of the battery is provided, and when the battery charge amount is equal to or less than a predetermined value based on the output of the charge determination unit, a part of the regenerative energy of the first motor is regenerated during regeneration. It is a control device for an electric vehicle, which is provided with a third energy converting means for converting the rotational energy of the motor into another energy and for charging the other part of the regenerative energy of the first motor into the battery.

According to a seventh aspect of the present invention, in addition to the configuration of the fourth or fifth aspect of the invention, an electric vehicle provided with an accelerator opening sensor for detecting the acceleration request based on the magnitude of the accelerator opening. It is a control device of.

According to the invention of claim 8 of the present invention, in addition to the structure of the invention of claim 2, an electric power in which the inertial force of the second motor is set to be large with respect to the inertial force of the first motor. It is a vehicle control device.

According to a ninth aspect of the present invention, in addition to the structure of the eighth aspect of the invention, the outer diameter of the rotor of the second motor is set to the outer diameter of the rotor of the first motor. It is a control device for an electric vehicle that is set to a large size.

According to a tenth aspect of the present invention, in addition to the structure of the eighth aspect of the invention, the total length of the rotor of the second motor is larger than the total length of the rotor of the first motor. It is a control device for an electric vehicle set to.

[0032]

According to the invention described in claim 1 of the present invention, as shown in the claim correspondence diagram of FIG. 6, the first motor P2 interlocked with the wheel P1 and the first motor P
A second motor P5 mechanically connected to the second output shaft P3 via a connecting / disconnecting unit P4, a load determining unit P6, and a control unit P7. The load determining unit P6 determines the magnitude of the load. However, the above-mentioned control means P7 drives only the first motor P2 when the load is light, based on the output of the load determination means P6, while both the first and second motors P2 and P when the load is high.
Drive 5 together.

That is, when the load applied to the motor is small, such as during steady running, the control means P7 turns off the connecting and disconnecting means P4 and concentrates all the load on the first motor P2. The first motor P2 can be used in a high-efficiency region shown by hatching in the motor isoefficiency diagram of No. 4, and when the load applied to the motor is large, the above-mentioned control means P7 is a disconnecting means. Turn on P4
By driving both motors P2 and P5 in this way, each motor P2 and P5 can be used in a high efficiency region shown by hatching the motor isoefficiency diagram of FIG.

As a result, since the motors P2 and P5 can be used in a region where the motor efficiency is always high, the efficiency can be improved in the entire operating region of the electric vehicle and the traveling distance per charge can be extended. effective.

According to the second aspect of the present invention,
In addition to the effect of the invention described in claim 1, the first energy conversion means stores the regenerative energy of the first motor as the rotational energy of the second motor during regeneration, and the second energy conversion means described above regenerates the energy. The first motor is driven by the rotational energy accumulated in the second motor during the transition from time to non-regeneration.

Since the regenerative energy at the time of regeneration is stored as the rotational energy of the second motor in this manner, the efficiency (about 85%) is higher than the efficiency (about 30%) for recovering the conventional regenerative energy in the battery. Thus, there is an effect that the regenerative energy can be stored and the recovered regenerative energy can be effectively used when shifting to the non-regenerative mode.

According to the invention of claim 3 of the present invention,
In addition to the effect of the invention described in claim 2, the first and second energy conversion means described above have first and second drive control means (specifically, drive control of the rotation speed of each motor separately). Since it has an inverter) and the above-mentioned supply path,
There is an effect that the rotation speed control of each motor, particularly the second motor, can be easily performed.

According to the invention of claim 4 of the present invention,
In addition to the effect of the invention according to claim 3, the acceleration determination means determines the magnitude of the acceleration request at the time of re-acceleration when transitioning from regeneration to non-regeneration, and the acceleration determination means detects that the acceleration request is small. At this time, the second energy converting means described above converts the rotational energy accumulated in the second motor into energy for driving the first motor, and drives the first motor. As a result, there is an effect that sufficient traveling performance can be ensured even when the acceleration request is small.

According to the invention of claim 5 of the present invention,
In addition to the effect of the invention as set forth in claim 3, the acceleration determination means determines the magnitude of the acceleration request at the time of re-acceleration when transitioning from regeneration to non-regeneration, and the acceleration determination means detects that the acceleration request is large. When this occurs, the energy conversion control by the second energy converting means is prohibited, and the first disconnecting means makes the first converting operation.
Since the second motors are connected to each other and both motors are driven by the battery power source, there is an effect that sufficient traveling performance can be ensured in response to a large demand for acceleration.

According to the invention of claim 6 of the present invention,
In addition to the effect of the invention described in claim 2, 3, 4 or 5, the charge determination means determines whether the charge amount of the battery is large or small, and the charge determination means determines that the battery charge amount is a predetermined value or less. When it is determined that the third energy conversion means stores a part of the regenerative energy of the first motor as the rotational energy of the second motor during regeneration, the other part of the regenerative energy of the first motor is stored in the battery. Since the electric energy is charged, there is an effect that the regenerative energy can be stored with higher efficiency.

According to the invention of claim 7 of the present invention,
In addition to the effect of the invention described in claim 4 or 5, since the acceleration request is detected by the accelerator opening sensor, it is possible to accurately detect the acceleration request corresponding to the stepping operation of the driver using the existing device. There is.

According to the invention of claim 8 of the present invention,
In addition to the effect of the invention described in claim 2, since the inertial force of the second motor is set to be large with respect to the inertial force of the first motor, the second motor when the second motor acts as a flywheel. It is possible to improve the rotational energy storage rate of the.

According to the invention of claim 9 of the present invention,
In addition to the effect of the invention described in claim 8, since the outer diameter of the rotor of the second motor is set to be larger than the outer diameter of the rotor of the first motor, the length of the second motor is suppressed. While the second
It is possible to improve the rotational energy storage rate of the motor.

According to the invention of claim 10 of the present invention, in addition to the effect of the invention of claim 8, the total length of the rotor of the second motor is made longer than the total length of the rotor of the first motor. Since the setting is made, it is possible to improve the rotational energy storage rate of the second motor while suppressing the outer diameter of the second motor.

[0045]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. The drawing shows a control device for an electric vehicle. In FIG. 1, the electric vehicle includes first and second motors M1 and M2.
Is configured to drive the left and right wheels 1 and 2. Here, a three-phase induction motor (squirrel cage) is used as each of the above-mentioned motors M1 and M2, but in the following description, they are simply referred to as motors.

The output shaft 3 of the above-mentioned first motor M1 is of a double shaft type, and one end of the output shaft 3 is provided with gears 4, 5, a propeller shaft 6, a differential device 7 and left and right drive shafts 8, 9. The above-mentioned wheels 1 and 2 are interlocked with each other.

The other end of the output shaft 3 of the first motor M1 and the output shaft 1 of the second motor M2 of which the output shaft is a single shaft type.
A clutch 11 serving as a connecting / disconnecting means is provided between 0 and
These two motors M1 and M2 are configured to be mechanically connectable.

The above-mentioned first motor M1 generates regenerative energy (generated energy) when the electric vehicle is traveling at a reduced speed and when the electric vehicle is traveling on a downhill, and this regenerative energy is, for example, each element 17 described later. , 19, 16 is supplied to the second motor M2.

The CPU 20 controls the rotation speed N of the first motor M1.
1, the number of revolutions N2 of the second motor M2, the accelerator opening Ac from the accelerator opening sensor 12 which detects the acceleration request based on the magnitude of the accelerator opening, the first and second motors M1,
The inverters 15 and 16 and the supply means 17 are driven and controlled in accordance with a program stored in the ROM 14 based on various necessary signal inputs such as the battery voltage V from the battery 13 that stores electric energy for driving M2, and R
The AM 18 stores data, maps and the like corresponding to the previous regeneration control determination graph F, the predetermined values V1 and V2 of the battery voltage, the predetermined accelerator opening value Aco, and the predetermined rotation speed value No (see FIG. 2).

The above-mentioned inverter 15 converts the DC power supply of the battery 13 into a three-phase AC power supply and, if necessary, performs a three-phase AC frequency conversion to change the rotation speed of the first motor M1. It is a drive control means.

Similarly, the above-mentioned inverter 16 is the battery 1
The DC power source 3 is converted into a three-phase AC power source, and the frequency of the three-phase AC is converted as necessary, so that the second motor M
It is a second drive control means for changing the rotation speed of No. 2.

The above-mentioned supply means 17 supplies the regenerative energy (generated energy) of the first motor M1 to the battery 13 and also supplies the above-mentioned generated energy to the inverter 16 (second drive) via the supply line 19 as a supply path. Control means) and, if necessary, after converting the rotational energy accumulated in the second motor M2 into electric energy, it is supplied to the first motor M1.

By the way, the inertial force of the second motor M2 is set to be larger than the inertial force of the first motor M1.
That is, when the second motor M2 stores regenerative energy as rotational energy, the rotor acts as a flywheel. Therefore, by increasing the rotor weight (mass), the inertial force of the second motor M2 is increased. Is set to be larger than that of the first motor M1.

When increasing the inertial force of the second motor M2,
When the outer diameter of the rotor of the second motor M2 is set larger than the outer diameter of the rotor of the first motor M1, the rotational energy of the second motor M2 is suppressed while suppressing the length of the second motor M2. The storage rate (kinetic energy storage efficiency) can be improved. On the other hand, if the total length of the rotor of the second motor M2 is set longer than the total length of the rotor of the first motor M1, the outside of the second motor M2 is It is possible to improve the rotational energy storage rate of the second motor M2 while suppressing the diameter dimension.
The outer diameter and the total length of the rotor of the motor M2 are set to the first motor M1.
When the outer diameter and the total length of the rotor are set to be large, the rotational energy storage rate of the second motor M2 can be further improved.

On the other hand, the CPU 20 described above has a load determining means (first subroutine of the subroutine shown in FIG. 3) for determining the magnitude of the load.
(See step S21) and the clutch 11 when the load is light (including when the load is low) based on the output of the load determining means described above.
Is disconnected to drive only the first motor M1, and the clutch 11 is connected at the time of high load to connect both the first and second motors M1.
Control means for driving both 1 and M2 (routine R1 consisting of steps S22 and S23 of the subroutine shown in FIG. 3)
And the regenerative energy (generated energy) of the first motor M1 during regeneration is supplied to the second motor M2 via the supply means 17, the supply line 19, and the inverter 16, and the rotor of the second motor M2 is used as a flywheel. Rotate as
The first energy conversion means (refer to the sixth step S6 of the main routine shown in FIG. 2) for accumulating the rotational energy in the second motor M2 and the second motor M2 for accumulating at the time of transition from the regenerative time to the non-regenerative time. After the clutch 11 is turned off and the electric energy is converted into electric energy once using the electric path, the first motor M is converted with this electric energy.
1 or drive energy for driving the first motor M1 is directly converted to drive energy for driving the first motor M1 by turning on the clutch 11 and using the mechanical path. 2 energy conversion means (corresponding to the twelfth step S12 of the main routine shown in FIG. 2, which corresponds to the former using an electric path in this embodiment),
A large acceleration request is detected by the acceleration determination means (see step S10 in the main routine shown in FIG. 2) for determining the magnitude of the acceleration request at the time of re-acceleration when transitioning from regeneration to non-regeneration and the acceleration determination means described above. At this time, the prohibiting means for prohibiting the energy conversion control by the second energy converting means (the eleventh step S11 of the main routine shown in FIG. 2).
When the prohibiting means prohibits the above, the clutch 11 is turned on to connect the first and second motors M1 and M2 to each other, and both motors M1 and M2 are connected.
2 is driven by a battery 13 power source (see FIG. 3).
(See step S23 of the subroutine shown in FIG. 2), charge determining means for determining the amount of charge of the battery 13 (see fifth step S5 of the main routine shown in FIG. 2), and output of the charge determining means. When the battery charge amount is less than or equal to a predetermined value (for example, under a full potential), a part of the regenerative energy of the first motor M1 is converted into the rotational energy of the second motor M2 during regeneration, and 1
It also serves as third energy conversion means (see seventh step S7 of the main routine shown in FIG. 2) for charging the battery 13 with the other part of the regenerative energy of the motor M1.

The operation of the thus configured electric vehicle controller will be described in detail below with reference to the flowcharts of FIGS. First, the main routine of FIG. 2 will be described. In the first step S1, the CPU 20 executes the initial setting (initialization) by setting the previous regeneration control determination flag F to F = 0, and in the next second step S2. The CPU 20 executes reading of various necessary signal inputs from the accelerator opening sensor 12, such as the current accelerator opening Ac, the battery voltage V, and the rotation speeds N1 and N2 of the motors M1 and M2.

Next, in a third step S3, the CPU 20 determines whether or not the accelerator opening is fully closed. When the accelerator is fully closed, the CPU 20 proceeds to the next fourth step S4 while the accelerator opening is not fully closed. When not regenerated, the process proceeds to another ninth step S9.

In the above-mentioned fourth step S4, the CPU 20R
The previous regeneration control determination flag F in the predetermined area of the AM 18 is set to F = 1 corresponding to the regeneration. Next, in a fifth step, the CPU 20 compares the current battery voltage V with the battery voltage predetermined value V1, determines whether V <V1, and determines whether V <V1.
> V1 (when the battery voltage V is equal to or higher than the predetermined value V1), the process proceeds to the next sixth step S6, and when V <V1 (when the battery voltage V is equal to or lower than the predetermined value V1), another 7th
Control goes to step S7.

In the above-described sixth step S6, the CPU 20 supplies the total amount of power generation of the first motor M1 to the second motor M2 and stores it as rotational energy. That is, the condition leading to step S6 is when the electric vehicle is decelerating or traveling downhill, and the battery voltage V is equal to or higher than the predetermined value V1, so the above-described first motor M1 functions as a generator. Then, in this sixth step S6, the CPU 20
Turns off the clutch 11 to supply the regenerative energy (generated energy) of the first motor M1 to the supply means 17 and the supply line 1.
9, supply to the second motor M2 via the inverter 16,
By rotating the rotor of the second motor M2 as a flywheel, the regenerative energy described above is accumulated as rotational energy.

Next, in the eighth step, the CPU 20 directs
Inverter 1 with AC conversion function and frequency conversion function
Controlling the rotation speed of the second motor M2 via 6 (frequency control)
To execute.

On the other hand, in the above-mentioned seventh step S7, the CPU
Reference numeral 20 divides the regenerative energy of the first motor M1 into a part and another part, accumulates a part of the regenerative energy as the rotational energy of the second motor M2 as in the process of the sixth step S6, and regenerative energy The other part is charged to the battery 13 via the supply means 17. Next, the process proceeds to the eighth step S8 described above.

By the way, at the time of non-regeneration when it is determined that the accelerator opening degree is not fully closed in the above-described third step S3, the CPU 20 sets the previous regeneration control determination flag F to F = 1 in the following ninth step S9. By determining whether or not it is determined whether the transition from regeneration to non-regeneration is performed or not, the following tenth step S10 is performed at the time of YES determination (when transitioning from regeneration to non-regeneration).
When NO is determined (non-regeneration continues), the process proceeds to another fifteenth step S15.

In the tenth step S10 described above, the CPU 2
0 is the current accelerator opening Ac and the accelerator opening predetermined value Ac
Ac is compared with o to determine the magnitude of the acceleration request, and Ac <Aco
When the acceleration request of is small, the process proceeds to the next twelfth step S12, and when the acceleration request of Ac> Aco is large, the process proceeds to another eleventh step S11.

In this eleventh step S11, the CPU 20
Compares the current battery voltage V with a predetermined battery voltage value V2, and when the battery charge amount of V <V2 is small, the process proceeds to the next twelfth step S12, while when the battery charge amount of V> V2 is large, it is different. Then, the process proceeds to the fifteenth step S15.

In the above-mentioned twelfth step S12, the CPU 2
0 supplies the energy accumulated as rotational energy in the second motor M2 to the supply means 17 and once converts it into electric energy, and then supplies this electric energy to the first motor M1. At this time, the clutch 11 is turned off. Instead of supplying energy through such an electric path, the following energy supply may be performed. That is, the clutch 11 may be turned on and the energy accumulated as rotational energy in the second motor M2 may be directly supplied to the first motor M1 via the mechanical path. In any case, the rotational energy accumulated in the second motor M2 is converted into the drive energy of the first motor M1.

Next, in a thirteenth step S13, the CPU 20
Compares the rotation speed N2 of the second motor M2 with a predetermined value No. When N2 <No, the rotation speed N2 of the second motor M2 is small, and the second step S14 is performed through the following fourteenth step S14.
When the rotation speed N2 of the second motor M2 of N2> No is large, the routine returns to the second step S2 without passing through the fourteenth step S14.

In the 14th step S14 described above, the CPU 2
0 sets the previous regeneration control determination flag F in a predetermined area of the RAM 18 to F = 0. By the way, in the above-mentioned fifteenth step S15, normal control is executed during power running, and this normal control is as shown in the subroutine of FIG.

Next, the subroutine of FIG. 3 will be described. In the first step S21, the CPU 20 executes the load judgment, and when the load is light including the low load, the following second step S2 is executed.
On the other hand, when the load is high, another third step S2
Move to 3.

In the above-mentioned second step S22, the CPU 20
Turns off the clutch 11 and drives only the first motor M1 in response to a light load. Also, the above-mentioned third step S2
At 3, the CPU 20 turns on the clutch 11 to drive both the first and second motors M1 and M2 in response to a high load. The processing in each of steps S22 and S23 described above is performed after the battery 13 power supply as a DC power supply is once converted into a three-phase AC power supply by the inverters 15 and 16, and the rotation speed is increased as the frequency is increased. Of course, it can be done.

In summary, the above-mentioned load determining means (see FIG.
The first step S21) determines whether the load is large or small, and the control means (see routine R1 in FIG. 3) drives only the first motor M1 when the load is light based on the output of the load determination means. When loaded, both the first and second motors M1 and M2 are driven.

That is, when the load applied to the motor is small, such as during steady running, the above-mentioned control means (see R1).
4 turns off the connecting / disconnecting means (see the clutch 11) to concentrate all the load on the first motor M1.
The first motor M1 can be used in a high-efficiency region shown by hatching the motor iso-efficiency diagram, and when the load applied to the motor is large, the above-mentioned control means (see R1) continues. By turning on the disconnecting means (see the clutch 11) to drive both motors M1 and M2, as shown in FIG.
The respective motors M1 and M2 can be used in a high efficiency region shown by hatching the motor isoefficiency diagram.

As a result, since the motors M1 and M2 can be always used in a region where the motor efficiency is high, the efficiency can be improved in the entire operating region of the electric vehicle and the traveling distance per charge can be extended. effective.

Further, the above-mentioned first energy conversion means (see sixth step S6 in FIG. 2) accumulates the regenerative energy of the first motor M1 as the rotational energy of the second motor M2 during regeneration, and at the same time the above-mentioned second energy conversion. Means (first in FIG. 2
In 2 step S12), the first motor M1 is driven by the rotational energy accumulated in the second motor M2 during the transition from the regeneration time to the non-regeneration time.

Since the regenerative energy at the time of regeneration is accumulated as the rotational energy of the second motor M2 in this way, the efficiency (about 85%) is higher than the efficiency (about 30%) for recovering the conventional regenerative energy in the battery. ), The regenerative energy can be stored, and the recovered regenerative energy can be effectively used during the transition from regenerative to non-regenerative.

Further, in the hardware structure constituting the above-mentioned first and second energy converting means, each motor M1,
Since each of the motors M1 and M2 is provided with the first and second drive control means (see inverters 15 and 16) for individually controlling the rotation speed of M2 and the above-mentioned supply path (see supply line 19). Especially, there is an effect that the rotation speed control of the second motor M2 can be easily performed.

In addition, the above-mentioned acceleration determination means (the first in FIG.
0 step S10) determines the magnitude of the acceleration request at the time of re-acceleration when transitioning from regeneration to non-regeneration, and when the acceleration determination means detects that the acceleration request is small, the above-mentioned second energy conversion means (Fig. 2 twelfth step S12), the rotational energy accumulated in the second motor M2 is transferred to the first motor M2.
It is converted into energy for one drive and drives the first motor M1. As a result, there is an effect that sufficient traveling performance can be ensured even when the acceleration request is small.

In addition, the above-mentioned acceleration determination means (first in FIG.
0 step S10) determines the magnitude of the acceleration request at the time of re-acceleration when transitioning from regeneration to non-regeneration, and when the acceleration determination means detects that the acceleration request is large, the second energy conversion means (FIG. 2). The energy conversion control by the twelfth step S12) is prohibited by the prohibiting means (see NO determination in the eleventh step of FIG. 2), and the first and second motors M by the connecting / disconnecting means (see the clutch 11).
Since the motors M1 and M2 are connected and the motors M1 and M2 are driven by a battery power source, there is an effect that sufficient traveling performance can be ensured in response to a large demand for acceleration.

Further, the above-mentioned charge determination means (see the fifth step S5 in FIG. 2) determines the magnitude of the charge amount of the battery 13, and the charge determination means determines that the battery charge amount is less than or equal to a predetermined value (V < When it is determined that V1),
The above-mentioned third energy conversion means (seventh step S7 in FIG. 2)
(See) stores a part of the regenerative energy of the first motor M1 as the rotational energy of the second motor M2 during regeneration and charges the other part of the regenerative energy of the first motor M1 to the battery 13 as electric energy. There is an effect that the regenerative energy can be stored with higher efficiency.

Furthermore, the acceleration request is sent to the accelerator opening sensor 1
Since it is detected by No. 2, there is an effect that the acceleration request corresponding to the stepping operation of the driver can be accurately detected using the existing device.

Furthermore, since the inertial force of the second motor M2 described above is set to be large with respect to the inertial force of the first motor M1, when the second motor M2 acts as a flywheel, the second motor M2 is used. There is an effect that the rotational energy storage rate can be improved.

In the correspondence between the structure of the present invention and the above-described embodiment, the connecting / disconnecting means of the present invention is the clutch 1 of the embodiment.
In the same manner, the load determination means corresponds to the CPU 20.
Corresponding to the first step S21 by control (see FIG. 3),
The control means corresponds to the routine R1 (see FIG. 3) and has a first
The energy converting means corresponds to the sixth step S6 (see FIG. 2), and the second energy converting means corresponds to the twelfth step S1.
2 (see FIG. 2), the first and second drive control means correspond to the inverters 15 and 16, the supply path corresponds to the supply line 19, and the acceleration determination means corresponds to the tenth step S10 (FIG. 2), the charge determination means corresponds to the fifth step S5 (see FIG. 2), and the third energy conversion means corresponds to the seventh step S7 (see FIG. 2). It is not limited to the configuration of the above embodiment.

[Brief description of drawings]

FIG. 1 is a system diagram showing a control device for an electric vehicle according to the present invention.

FIG. 2 is a flowchart showing energy conversion control.

FIG. 3 is a flowchart showing motor drive control.

FIG. 4 is an isoefficiency diagram when the first motor is driven.

FIG. 5 is an isoefficiency diagram when driving both motors.

FIG. 6 is a diagram for responding to a complaint.

FIG. 7 is a motor isoefficiency diagram showing a conventional example.

[Explanation of symbols]

 1, 2 ... Wheels 3 ... Output shaft 11 ... Clutch 12 ... Accelerator opening sensor 13 ... Battery 15, 16 ... Inverter 19 ... Supply line M1 ... First motor M2 ... Second motor S5 ... Charge determination means S6 ... First energy Conversion means S7 ... Third energy conversion means S10 ... Acceleration determination means S12 ... Second energy conversion means S21 ... Load determination means R1 ... Control means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiji Tamura 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation

Claims (10)

[Claims] 1. A first motor linked to a wheel, a second motor mechanically connected to an output shaft of the first motor through a connecting / disconnecting means, and a load determining means for determining the magnitude of a load. A control device for an electric vehicle including control means for driving the first motor when the load is light and driving both the first and second motors when the load is high based on the output of the load determining means. 2. A first motor which is interlocked with the wheels to generate regenerative energy in a predetermined operating region, a second motor to which regenerative energy of the first motor is supplied, and regenerative energy of the first motor during regeneration. Energy conversion means for converting and controlling the rotational energy of the second motor into rotational energy of the second motor, and second energy for converting and controlling rotational energy of the second motor into drive energy of the first motor during transition from regeneration to non-regeneration. The control device for an electric vehicle according to claim 1, further comprising a conversion unit. 3. The first and second energy conversion means, first and second drive control means for driving and controlling the rotation speeds of the first and second motors, respectively, and the first motor regeneration time. The control device for an electric vehicle according to claim 2, further comprising: a supply path that supplies generated energy to the second drive control means. 4. An accelerating means for determining the magnitude of an acceleration request at the time of re-acceleration for transition from regeneration to non-regeneration, and when the acceleration determination means detects that the acceleration request is small, the second energy converting means. The rotational energy of the second motor is converted into drive energy of the first motor by means of
The electric vehicle control device described. 5. A large acceleration request is provided by the acceleration determination means for determining the magnitude of the acceleration request at the time of transition from regeneration to non-regeneration, by providing a battery for accumulating energy for driving each of the first and second motors. 4. When the above is detected, the energy conversion control by the second energy converting means is prohibited, the first and second motors are connected by the connecting and disconnecting means, and both motors are driven by a battery power source. Electric car control device. 6. A charge determination means for determining the amount of charge of the battery is provided, and when the battery charge amount is below a predetermined value based on the output of the charge determination means, the regenerative energy of the first motor is regenerated during regeneration. The third energy conversion means for converting a part of the regenerative energy of the first motor into a rotational energy of the second motor and charging the other part of the regenerative energy of the first motor to a battery.
The control device for an electric vehicle according to 3, 4, or 5. 7. A control device for an electric vehicle according to claim 4, further comprising an accelerator opening sensor for detecting the acceleration request according to the magnitude of the accelerator opening. 8. The electric vehicle control device according to claim 2, wherein the inertial force of the second motor is set to be large with respect to the inertial force of the first motor. 9. The outer diameter of the rotor of the second motor is set to the first outer diameter.
9. The control device for an electric vehicle according to claim 8, wherein the outer diameter of the rotor of the motor is set to be large. 10. The total length of the rotor of the second motor is set larger than the total length of the rotor of the first motor.
The electric vehicle control device described.