JP5338390B2 - Electric vehicle motor control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor controller of an electric vehicle that reduces the number of motor revolutions using a three-phase short circuit without increasing energy quantity, while controlling the number of motor revolutions to a target number of revolutions in a short period of time. <P>SOLUTION: The motor controller of the electric vehicle is equipped with: a motor-torque calculating means 113 for controlling the motor torque so that actual number of motor revolutions attains the target number of motor revolutions; an inverter three-phase output unit 140 performing three-phase short circuiting to a motor generator MG to reduce the number of motor revolutions; and an integrated controller 1 to reduce the number of motor revolutions by the three-phase short circuiting at the three-phase output unit 140 on shifting a gear from Low to High, to interrupt the three-phase short circuiting when the number of motor revolutions reaches the number of revolutions Nth for stopping the three-phase short circuiting set higher than the target number of motor revolutions, and to perform a feedback control to the number of revolutions so that the actual number of motor revolutions reaches the target number of motor revolutions by the motor-torque calculating means 113. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a motor control device for an electric vehicle, and more particularly to a technique for executing control for reducing the motor rotation speed using a three-phase short circuit.

In a conventional motor control device for an electric vehicle, for example, Japanese Patent Application Laid-Open No. H10-228707 is known in which a motor is braked by three-phase short-circuiting.
This prior art has a field winding type electric motor having a field winding and a field current control means for controlling a field current flowing in the field winding of the motor, and the motor armature during braking of the motor Armature winding short-circuiting means for short-circuiting the windings is provided, and the field current control means controls the field current so that the braking force acts on the motor during braking of the motor.

JP 2005-168083 A

  However, when a conventional motor control device for an electric vehicle performs a three-phase short circuit, the motor speed can be reduced without charging the battery. However, since the three-phase short circuit can only be turned ON and OFF, a certain target speed When the rotational speed is decreased toward the target, the target rotational speed is greatly overshot, and it takes time to match the target rotational speed.

  The present invention has been made by paying attention to the above-mentioned problem. While the motor rotation speed can be reduced without increasing the amount of energy using a three-phase short circuit, the motor rotation speed can be set to the target rotation speed in a short time. An object of the present invention is to provide a motor control device for an electric vehicle that can be controlled.

  In order to achieve the above object, the motor control device for an electric vehicle according to the present invention reduces the motor speed by a three-phase short circuit caused by a three-phase short circuit during a shift from a low gear to a high gear. When the short-circuiting stop speed set higher than the motor target speed is reached, the three-phase short-circuit is stopped, and then the speed feedback control unit controls the speed feedback so that the actual motor speed becomes the motor target speed. The motor control device for the electric vehicle is provided with a motor control means for executing the above.

  In the motor control device for an electric vehicle according to the present invention, when the transmission shifts from the low speed stage to the high speed stage, the clutch is released, the motor and the transmission are disconnected, and the motor rotational speed upstream of the clutch is changed to the speed change downstream of the clutch. The motor rotation speed is reduced so that the input rotation speed of the machine is reached, and the clutch is engaged.

  When reducing the motor rotation speed to the motor target rotation speed during such a shift, the motor control device for an electric vehicle according to the present invention first brakes the motor by a three-phase short circuit by the three-phase short circuit unit, and in a short time. The rotation speed is decreased to the short-circuit stop rotation speed, and then the rotation speed is decreased from the short-circuit cancellation rotation speed to the motor target rotation speed by the rotation speed feedback control by the rotation speed feedback control unit.

  Therefore, while using a three-phase short circuit to reduce the rotational speed with high response without increasing the energy, the rotational speed reduction from the motor target rotational speed to the short-circuiting stopped rotational speed is exceeded by the rotational speed feedback. The number of revolutions can be reduced without shooting. Therefore, it is possible to reduce the rotational speed while suppressing an increase in the amount of energy, and it is possible to reduce the motor rotational speed and the target rotational speed in a shorter time than when overshoot occurs.

1 is an overall system diagram illustrating a motor control device for an electric vehicle according to a first embodiment. 1 is a schematic diagram illustrating an example of an automatic transmission AT applied to Embodiment 1. FIG. FIG. 3 is a collinear diagram of a planetary gear mechanism PG of the automatic transmission AT shown in FIG. 2. FIG. 6 is a shift characteristic diagram in an automatic transmission AT of a hybrid vehicle to which the clutch control device of Embodiment 1 is applied. It is a block diagram which shows the structure which calculates the motor torque command value and three-phase output in Example 1. FIG. 3 is a flowchart showing a flow of a process of motor rotation speed control associated with an increased speed change in the first embodiment. 3 is a time chart showing an operation example at the time of a speed increasing shift according to the first embodiment. It is a block diagram which shows the structure which calculates the motor torque command value and three-phase output in Example 2. FIG. 6 is a time chart showing an operation example at the time of a speed increasing shift according to the second embodiment. 6 is a flowchart illustrating a flow of a process for controlling the motor rotation speed in association with a speed increasing shift in the second embodiment. 10 is a flowchart showing a flow of processing at the time of sudden grip determination in Embodiment 3. 10 is a flowchart showing a flow of processing when traveling downhill in the third embodiment.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The clutch control apparatus according to the embodiment of the present invention includes a motor (MG) as a drive source for driving the drive wheels (LT, RT), and the motor (MG) and the drive wheels (LT, RT). A transmission (AT) capable of changing the gear ratio to at least a low gear stage having a relatively large gear ratio and a high gear stage having a relatively small gear ratio, and the motor (MG) according to the vehicle state. ) Target rotational speed calculation means (112) for calculating the target rotational speed of the motor (MG), a motor rotational speed sensor (21) for detecting the actual rotational speed of the motor (MG), and the actual motor rotational speed. A rotation speed feedback control section (113) for controlling the motor torque so that the motor rotation speed becomes the motor target rotation speed, and a three-phase short-circuit section (140) for reducing the motor rotation speed by three-phase short-circuiting the motor (MG). The low gear At the time of shifting to a high gear, the motor rotation speed is reduced by a three-phase short circuit by the three-phase short circuit (140), and the motor rotation speed reaches a short-circuit stop rotation speed set higher than the motor target rotation speed. Then, the motor control means (1) for stopping the three-phase short circuit, and thereafter, executing the rotational speed feedback control so that the actual motor rotational speed becomes the motor target rotational speed by the rotational speed feedback control unit (113), A motor control device for an electric vehicle characterized by comprising:

  A clutch control device according to a first embodiment of the best mode for carrying out the invention will be described with reference to FIGS.

  First, the configuration of the drive system and the control system will be described based on a schematic diagram showing a rear wheel drive type electric vehicle to which the motor control device for an electric vehicle according to the first embodiment of FIG. 1 is applied.

(Configuration of drive system)
First, the configuration of the drive system of the electric vehicle to which the first embodiment is applied will be described.
As shown in FIG. 1, the drive system of the electric vehicle to which the first embodiment is applied includes a motor generator MG, a battery BAT, an automatic transmission AT, a propeller shaft PS, a differential DF, a left drive wheel LT, and a right drive wheel RT. ing.

  Motor generator MG has an AC synchronous motor structure, and performs drive torque control and rotation speed control when starting and running, and recovers vehicle kinetic energy to battery BAT by regenerative brake control during braking and deceleration. is there.

The automatic transmission AT is a transmission capable of shifting in two stages, a low gear (low gear stage) and a hi gear (high gear stage), and is interposed between the motor generator MG and the differential DF.
As shown in FIG. 2, the automatic transmission AT includes a planetary gear mechanism PG, a low clutch LC, and a high clutch HC. In the planetary gear mechanism PG, the input shaft IPS is coupled to the output side member 102 of the clutch CL, the sun gear Sg is coupled to the input shaft IPS, and the carrier Ca is coupled to the propeller shaft PS. The ring gear Rg can be connected to and released from the housing HS by the low clutch LC, and can be connected to and released from the sun gear Sg (input shaft IPS) by the high clutch HC.

  Therefore, the automatic transmission AT used in the first embodiment can form a low gear by disengaging the high clutch HC and engaging the low clutch LC. In this case, the ring gear Rg is fixed, and as shown in the collinear diagram of FIG. 3, the sun gear Sg rotates integrally with the input shaft IPS, and the carrier Ca rotates at a reduced speed integrally with the output shaft OTS.

  On the other hand, the Hi gear can be formed by engaging the high clutch HC and releasing the low clutch LC. In this case, the sun gear Sg, the carrier Ca, and the ring gear Rg are integrally rotated at a constant speed.

  The clutch CL described above is interposed between the motor generator MG and the automatic transmission AT so that the transmission torque can be changed. The input side member 101 of the clutch CL is connected to the motor generator MG via an output gear OTG. Further, as described above, the output side member 102 of the clutch CL is coupled to the input shaft IPS of the automatic transmission AT.

(Control system configuration)
Next, the configuration of the control system of the electric vehicle to which the first embodiment is applied will be described.
The control system of the electric vehicle includes an integrated controller (motor control means) 1, a battery controller 11, a clutch controller 12, an AT controller 13, and a motor controller 14.
The integrated controller 1 includes a motor speed sensor 21, an AT input speed sensor 22, a vehicle speed sensor 23, a wheel speed sensor 24, an accelerator sensor 25, and the like as means for detecting a running state. A detection value is input.

  The integrated controller 1 determines the power generation torque command value, the motor torque command value, the clutch torque command value from the battery state, accelerator opening, vehicle speed (value synchronized with the transmission output speed) obtained from the sensors 21 to 25, etc. And so on. Then, based on this calculation result, command values for motor generator MG and clutch CL are transmitted to controllers 11-14.

  The battery controller 11 manages the state of charge (battery charge / discharge SOC) of the battery BAT and transmits the information to the integrated controller 1.

  The clutch controller 12 controls the current of a solenoid valve provided in the clutch CL so as to realize the clutch hydraulic pressure (current) command value with respect to the clutch hydraulic pressure command value from the integrated controller 1.

  The AT controller 13 outputs a command signal for controlling the gear determined by the shift request determination unit 111 (see FIG. 5) of the integrated controller 1 toward the automatic transmission AT. Note that the shift request determination unit 111 determines which gear ratio to select between the low gear and the hi gear according to the accelerator opening and the vehicle speed based on a preset shift map shown in FIG. . In the shift map, hysteresis for preventing hunting is set for switching from the Low gear to the Hi gear and vice versa, for switching from the Hi gear to the Low gear.

  The motor controller 14 drives the motor generator MG via the inverter 2 so as to achieve the power generation torque command value, the motor torque command value, and the motor rotation speed command value from the integrated controller 1.

The motor rotation speed sensor 21 detects the rotation speed of the motor generator MG and the input rotation speed of the clutch CL.
The AT input rotational speed sensor 22 detects the input rotational speed of the automatic transmission AT and the output rotational speed of the clutch CL.
The vehicle speed sensor 23 is provided in the drive transmission system of the propeller shaft PS from the ring gear Rg of the planetary gear mechanism PG, and detects the vehicle speed.
The wheel speed sensor 24 is provided on each wheel and detects the number of rotations of each wheel.
The accelerator sensor 25 is provided in an accelerator pedal operation transmission system (not shown) and detects the accelerator opening.

(About motor speed control)
Next, a description will be given of the motor control executed in the integrated controller 1, and in particular, the configuration for executing the motor rotation speed control when shifting the automatic transmission AT from the Low gear to the Hi gear.

  The integrated controller 1 includes a shift request determination unit 111, a target rotation number calculation unit 112, a motor torque calculation unit (rotation number feedback control unit) 113, a short circuit stop rotation number calculation unit 114, and a three-phase short circuit availability determination unit illustrated in FIG. 115. Inverter output command section (three-phase short-circuit section) 140 is a part of motor controller 14 and is a section that performs three-phase output toward motor generator MG.

  As described above, the shift request determination unit 111 determines which gear ratio to select between the low gear and the hi gear based on the shift map.

  Target rotational speed calculation means 112 calculates a motor target rotational speed that is a target rotational speed of motor generator MG. This motor target rotational speed is calculated from the driver's drive request and gear ratio based on the accelerator opening. At the time of shifting from the Low gear to the Hi gear, the wheel speed and the gear ratio determined by the gear shift request determination unit 111 are determined. It calculates from the shift request flag shown.

  The motor torque calculation means 113 determines a motor torque command value based on the motor target rotational speed, and performs rotational speed feedback control based on a deviation between the motor target rotational speed and the detected actual motor rotational speed.

The short-circuit stop rotation speed calculation means 114 determines a short-circuit stop rotation speed addition value α that serves as a guide for the rotation speed at which the three-phase short-circuit is stopped when a three-phase short-circuit described later is executed. The number addition value α is determined by the battery chargeable amount and the target regenerative torque based on the arithmetic expression shown in the following expression (1).
α (rpm) = Battery chargeable amount (W) ÷ Target regeneration torque (1)
The battery chargeable amount is a charge amount that can be charged to the battery BAT at that time, and is calculated based on the battery charge / discharge amount SOC, the battery temperature, and the like.

  The three-phase short circuit availability determination means 115 permits the three-phase short circuit when the actual motor speed is equal to or greater than the three-phase short-circuit stop rotation speed Nth obtained by adding the short-circuit stop rotation speed addition value α to the motor target rotation speed, and the actual motor rotation When the number becomes less than the three-phase short circuit stop rotational speed Nth, the three-phase short circuit is prohibited.

  Inverter three-phase output unit 140 performs output for driving motor generator MG based on the motor torque command value, and also performs output for short-circuiting motor generator MG by a three-phase short-circuit command.

(Flow of motor speed control process during Low → Hi shift)
Next, based on the flowchart of FIG. 6, the flow of the process of the motor speed control executed when shifting the automatic transmission AT from the Low gear to the Hi gear will be described.
The motor speed control shown in this flowchart is started when the shift request determination unit 111 determines that the speed-up side shift from the Low gear to the Hi gear. In parallel with the motor speed control, a process for shifting the automatic transmission AT from the low gear to the HI gear is executed.

In step S1, the clutch CL is released, and the transmission and the motor generator are disconnected.
In step S2, it is determined whether or not the battery chargeable amount is small, that is, whether or not it is less than a preset regeneration prohibition threshold. If it is greater than or equal to the regeneration prohibition threshold, the process proceeds to step S3, and if it is less than the rotation prohibition threshold. If so, the process proceeds to step S4.

In step S3, the motor generator MG is regenerated to reduce the motor rotation speed, and the process proceeds to the next step S4.
In step S4, it is determined whether or not the motor rotation speed substantially matches the AT input rotation speed. If they match, the process proceeds to step S5 to engage the clutch CL. That is, during the clutch engagement in step S5 after the clutch is released in step S1, the automatic transmission AT has completed the shift, and the clutch CL can be engaged without causing a shift shock.

In step S6, the short-circuit stop rotational speed addition means α calculates the short-circuit stop rotational speed addition value α from the battery chargeable amount and the target regeneration torque, and further, from this short-circuit stop rotational speed addition value α, the following formula ( The three-phase short circuit stop rotational speed Nth is calculated by 2), and the process proceeds to the next step S7.
Nth = motor target rotational speed + α (2)
In step S7, the three-phase short circuit availability determination means 115 determines whether or not the actual motor speed is less than the three-phase short circuit stop rotational speed Nth. The process proceeds to step S9 as cancellation, and if it is equal to or higher than the three-phase short circuit cancellation rotation speed Nth, the process proceeds to step S8 as three-phase short circuit permission.
In step S8, the three-phase short circuit is turned on to decelerate motor generator MG.

On the other hand, in step S9 that proceeds when it is determined that the three-phase short-circuit is stopped, the three-phase short-circuit is turned OFF, and the process proceeds to step S10.
In step S10, the motor torque calculation means 113 performs the rotational speed feedback control of the motor generator MG, and outputs a motor torque command value for reducing the motor rotational speed so that the actual motor rotational speed matches the motor target rotational speed. The process proceeds to step S11.

  In step S11, the motor torque calculation means 113 determines whether or not the motor rotation speed substantially matches the AT input rotation speed. If the motor rotation speed substantially matches, the process proceeds to step S12 to engage the clutch CL. Also in this case, the shift in the automatic transmission AT is completed at this point, and no shock is generated when the clutch is engaged.

(Operation of Example 1)
Next, the operation example of Example 1 is demonstrated based on the time chart of FIG.
This time chart shows an operation example when a shift request from the Low gear to the Hi gear is generated in a state where the chargeable amount of battery is less than the regeneration prohibition threshold. It should be noted that the amount of chargeable battery decreases when the battery fails, when the charge / discharge amount of the battery decreases due to low temperatures, or when the battery is nearly fully charged due to regeneration.

  As shown in this time chart, a shift request is generated at the time t1, the shift process is performed by the AT controller 13, and the shift is completed at the time t3.

  Due to the occurrence of this speed change request, after calculating the three-phase short-circuit stop rotation speed Nth based on the processing of steps S1 → S2 → S6 at the time t1, the actual motor rotation speed is greater than the three-phase short-circuit stop rotation speed Nth. Since it is large, the three-phase short circuit is turned on based on the processing of steps S7 → S8. Thereby, the motor generator MG is braked without generating power by regeneration, and the motor rotation speed is reduced.

  Thereafter, at the time t2 when the motor rotation speed becomes less than the three-phase short-circuit stop rotation speed Nth, the three-phase short-circuit is switched OFF and the motor torque calculation means 113 based on the processing of steps S7 → S9 → S10. Then, the actual motor rotational speed is decreased toward the motor target rotational speed by the rotational speed feedback control. In this case, the speed of decrease in the rotational speed is slower than that in the case of the three-phase short circuit, but the rotational speed feedback control reduces the motor rotational speed without overshooting the motor target rotational speed.

  Before and after the time t2, the motor torque command value output from the motor torque calculator 113 is negative for a moment in order to suppress a decrease in the motor rotation speed as the motor rotation speed approaches the motor target rotation speed. After that, the actual motor rotation speed is gradually decreased toward the target rotation speed by turning from minus to plus.

  Thus, when the actual motor rotational speed substantially coincides with the AT input rotational speed, the clutch CL is engaged based on the processing of steps S11 → S12, and thereafter, the speed is increased by the Hi gear.

(Effect of Example 1)
As described above, the effects listed below can be obtained in the first embodiment.
a) When shifting from the Low gear to the Hi gear, in a situation where the battery chargeable amount is small and overcharging occurs when regeneration is performed, regeneration is used because a three-phase short circuit is used to reduce the motor speed. Compared with lowering the motor speed, the battery speed can be rapidly reduced without overcharging the battery BAT, and the response is excellent.
In addition, when the motor rotation speed decreases to the three-phase short circuit stop rotation speed Nth, the three-phase short circuit is stopped and the motor rotation speed is decreased toward the motor target rotation speed by the rotation speed feedback control. Compared to the control using a three-phase short circuit until it becomes, it is possible to reach the motor target rotational speed in a short time without overshooting, and in this respect also, the control response is excellent.

  b) The short-circuit stop rotational speed addition value α is set to perform regeneration within the range of the battery chargeable amount during the rotational speed feedback control based on the battery chargeable amount (W). Even if the rotational speed feedback control is performed later, the battery can be prevented from being overcharged.

(Other examples)
Other embodiments will be described below. Since these other embodiments are modifications of the first embodiment, only the differences will be described, and the configuration common to the first embodiment or the other embodiments will be described. The description is omitted by giving a common reference numeral.

  The second embodiment is a modification of the first embodiment, and a part of the motor rotation speed control of the integrated controller 1 is different from the first embodiment. In addition, the same code | symbol is attached | subjected to the step which performs the same process as the flowchart of Example 1, and description is abbreviate | omitted.

  In the second embodiment, the three-phase short circuit availability determination means 215 shown in the block diagram of FIG. 8 determines whether or not a three-phase short circuit is possible based on the motor torque command value. That is, as shown in the time chart of FIG. 9, the three-phase short circuit availability determination means 215 calculates the motor rotation speed at the time when the motor torque command value changes from minus to plus after the three-phase short circuit is performed. The stop rotational speed Nth is configured to prohibit the three-phase short circuit and switch to the rotational speed feedback control.

  Therefore, in the second embodiment, as shown in the flowchart of FIG. 10, in step S <b> 206, which is determined as YES in step S <b> 2, the three-phase short circuit stop rotation speed Nth is obtained based on the motor torque command value. In the subsequent step S207, while the motor torque command value is negative, the process proceeds to step S8, and when it turns to positive, the process proceeds to step S9.

(Effect of Example 2)
When the actual motor speed approaches the motor target speed and the motor torque command value changes from negative to positive in order to loosen the braking force of the motor generator MG, the three-phase short-circuit is stopped and rotational speed feedback control is performed. I migrated.
For this reason, even if it shifts to rotation speed feedback control, possibility that regeneration will be performed in motor generator MG is very low, and it will reduce motor rotation speed without being charged by regeneration exceeding the battery chargeable amount. Can do.

  The third embodiment is an example in which a control for performing a three-phase short circuit is added to the motor control device of the first or second embodiment other than the shift from the Low gear to the Hi gear.

  That is, as shown in the flowchart of FIG. 11, when a later-described sudden grip determination is made in step S301, the process proceeds to step S302 to determine whether or not the battery chargeable amount is small, and the battery chargeable amount is small. Advances to step S303 to turn on the three-phase short circuit.

The sudden grip determination is performed when it is determined that it is necessary to apply a sudden braking force to the drive wheel, for example, when the vehicle suddenly stops or when the drive wheel slips such as overcoming a step or sudden acceleration. Made.
Further, whether or not the battery chargeable amount in step S302 is small is determined based on whether or not the battery chargeable amount is less than the regeneration prohibition threshold as in the first embodiment. It can occur at the time of failure, extremely low temperature, full charge, etc.

  Further, in the third embodiment, as shown in the flowchart of FIG. 12, in step S311 that proceeds when the battery chargeable amount is small in step S311, a downhill traveling determination is made, and an accelerator OFF inertial traveling determination is made. If it is determined that the speed has increased, the process proceeds to step S313 to set the three-phase short-circuit ON.

(Effect of Example 3)
In the third embodiment configured as described above, when the vehicle suddenly stops, or when the drive wheel slips such as when overcoming a step or when suddenly accelerating, it is necessary to apply a sudden braking force to the drive wheel. Sometimes the motor speed is reduced.
At this time, if the battery chargeable amount is less than the regeneration prohibition threshold and there is a possibility of overcharging if regeneration is performed, the three-phase short circuit is turned on based on the processing of steps S301 → S302 → S303, and the motor generator MG The motor speed can be reduced without generating electricity.

  Thereby, it is possible to reduce the motor rotation speed with high responsiveness while preventing the overcharged state of the battery BAT and the overspeed of the engine.

Also, in a situation where the battery is running near a fully charged state and the vehicle speeds up while not stepping on the accelerator, the three-phase short circuit is turned on based on the processing of steps S311 → S312 → S313, The motor rotational speed is reduced without being performed.
Therefore, the battery BAT does not become overcharged, and the braking force of the motor generator MG due to the three-phase short circuit reduces the operating amount of the mechanical brake device, thereby reducing the heat generation, wear and energy release of the brake. .

  As mentioned above, although the motor control apparatus of the electric vehicle of this invention has been demonstrated based on Embodiment and Examples 1-3, a specific structure is not restricted to these Examples, and it is a claim. Modifications and additions of the design are permitted without departing from the spirit of the invention according to the claims.

  In the first to third embodiments, the electric vehicle including only the motor generator MG as the drive source is shown. However, the vehicle type is not limited to the electric vehicle as long as it has a motor as the drive source. The present invention can also be applied to a so-called hybrid vehicle having an engine as a source.

  In the first to third embodiments, the rear-wheel drive vehicle is shown. However, the present invention is not limited to this, and can be applied to a front-wheel drive or four-wheel drive vehicle.

  In the first to third embodiments, the two-speed transmission of the Low gear and the Hi gear is shown as the transmission. However, the transmission is not limited to this, and a transmission that can change the speed to a plurality of stages of three or more stages is used. Also good. Although an automatic transmission is shown as a transmission, other types of transmissions such as a manual transmission may be used.

  Moreover, although the example provided with the battery BAT was shown in Examples 1-3, it can apply also to the structure which the motor MG drives only the part for the electric power generation of a generator, and is not provided with a battery.

1 Integrated controller (motor control means)
21 Motor rotation speed sensor 112 Target rotation speed calculation means 113 Motor torque calculation means (rotation speed feedback means)
114 Short-circuit stop rotational speed calculation means 140 Inverter three-phase output section (three-phase short-circuit section)
AT automatic transmission LT left drive wheel MG motor generator (motor)
Nth Three-phase short-circuit stop speed RT Right drive wheel α Short-circuit stop speed addition value

Claims (1)

A motor generator that is a drive source for driving the drive wheels and can charge the battery by regeneration; and
A battery controller for managing the state of charge of the battery;
A transmission that is interposed between the motor generator and the drive wheels and capable of changing the speed ratio to at least a low speed stage having a relatively large speed ratio and a high speed stage having a relatively small speed ratio;
Target rotational speed calculation means for calculating a motor target rotational speed that is a target rotational speed of the motor generator according to a vehicle state;
A motor speed sensor for detecting an actual speed of the motor generator;
A rotational speed feedback control unit for controlling the motor torque so that the actual motor rotational speed becomes the motor target rotational speed;
A three-phase short-circuit part that reduces the motor rotation speed by three-phase short-circuiting the motor;
Motor control means for reducing the motor rotation speed when shifting from the low gear to the high gear,
The motor control means, when the motor rotation speed is reduced,
If the battery chargeable amount of the battery is less than the regeneration prohibition threshold, the regeneration is performed to reduce the motor rotational speed,
On the other hand, when the battery chargeable amount exceeds the regeneration prohibition threshold, the motor rotation speed is reduced by a three-phase short circuit by the three-phase short circuit unit, and the motor rotation speed is set higher than the motor target rotation speed. The short-circuit stop rotational speed is reached, the three-phase short-circuit is stopped, and then the rotational speed feedback control unit performs rotational speed feedback control so that the actual motor rotational speed becomes the motor target rotational speed , and The motor control device for an electric vehicle is characterized in that the short-circuit stop rotational speed is calculated by adding a short-circuit stop rotational speed addition value determined by the battery chargeable amount and a target regeneration torque to the motor target rotational speed. .

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