JP6983305B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device.

Conventionally, a vehicle control device including a battery, a motor, and an inverter circuit has an overvoltage protection function. For example, if an abnormality occurs in which the connection between the battery and the inverter circuit is cut while the vehicle is running, the voltage applied to the circuit element constituting the inverter circuit becomes excessive due to the induced voltage accompanying the rotation of the motor, which may lead to the failure of the circuit element.

On the other hand, the technique described in Patent Document 1 is known as a technique for suppressing the generation of overvoltage when the connection between the battery and the inverter circuit is cut off. According to Patent Document 1, when a rotary electric machine is functioning as a generator and a circuit breaker or the like connecting a control device and a DC power supply is opened due to vibration of a vehicle or the like, a sudden voltage rise occurs in the charging path of the control circuit. It is described that when it occurs and the overvoltage determining means determines that it is overvoltage, the power conversion device puts the rotary electric machine in a phase short-circuit state.

Japanese Unexamined Patent Publication No. 2006-340599

When the power conversion device described in Patent Document 1 puts the rotary electric machine in a phase short-circuited state, it is possible to suppress the overvoltage and quickly reduce the voltage, and the circuit element used for the control device is deteriorated or damaged due to the overvoltage. It becomes possible to protect.

However, the effect is limited to this, and it is difficult to quickly control the motor by reconnecting the battery and the inverter circuit from the phase short-circuit state in which the torque control of the motor is lost.

An object of the present invention is a vehicle capable of continuously controlling the torque of a motor even when the connection between the battery and the inverter circuit is disconnected, and continuously controlling the torque of the motor even when the battery and the inverter circuit are reconnected. It is to realize a control device.

In order to solve the above problems, the present invention is configured as follows.

In a vehicle control device, a motor that generates a driving force of a vehicle, an inverter circuit that is composed of a switching element and drives the motor, a battery that is connected to the inverter circuit and supplies power to drive the motor, and the above. A capacitor connected between the battery and the inverter circuit, a contactor connected between the battery and the capacitor, and a voltage between the inverter circuit and the motor when the contactor is off. A control unit for passing a current between the inverter circuit and the motor so as to approach the voltage applied to the capacitor side is provided , the control unit vector-controls the motor, and the control unit controls the motor. A voltage sensor that detects the voltage across the capacitor, a current sensor that detects the current flowing on the high potential side of the battery, and feedback that calculates and outputs a torque command that brings the current detected by the current sensor closer to the target current. It has a control unit and a current command calculation unit that outputs a q-axis current command value and a d-axis current command value for vector control. In the current command calculation unit, the voltage detected by the voltage sensor is the first threshold value. When the voltage is equal to or lower than the voltage, the d-axis current command value and the q-axis current command value are calculated and output based on the torque command input from the outside, and the voltage detected by the voltage sensor is the first threshold value. When the voltage exceeds the first threshold voltage after the voltage is equal to or lower than the voltage, the d-axis current command value and the q-axis current command value are calculated and output based on the torque command output by the feedback control unit. When the voltage detected by the voltage sensor exceeds the first threshold voltage and then becomes lower than the second threshold voltage lower than the first threshold voltage, the d-axis current is based on a torque command input from the outside. It is characterized in that the command value and the q-axis current command value are calculated and output.

According to the present invention, the torque control of the motor can be continued even when the connection between the battery and the inverter circuit is cut off, and the torque control of the motor can be continued even when the battery and the inverter circuit are reconnected. A control device can be realized.

Issues, configurations and effects other than those described above will be clarified by the following description of the embodiments.

It is a block diagram which shows the structure of the motor control system which concerns on this invention. It is a processing block diagram of the controller which performs the motor control which concerns on this invention. It is a processing flow which shows the processing procedure at the time of opening the contactor which concerns on this invention. It is a timing diagram of each signal in the processing at the time of opening the contactor which concerns on this invention. It is a processing block diagram of the controller which performs the motor control which concerns on this invention. It is a processing flow which shows the processing procedure at the time of opening the contactor which concerns on this invention. It is a block diagram which shows the structure of the motor control system which concerns on the brake compensation which concerns on this invention.

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

(Example 1)
FIG. 1 is a configuration example of a motor control system that drives a vehicle with the motor of the first embodiment.

The motor control system of the first embodiment, which is an example of the vehicle control device according to the present invention, mainly includes an inverter circuit 1, a motor 101, a battery 201, and a controller 51.

The motor 101 is connected to a drive mechanism of a vehicle (not shown), and the vehicle is propelled by the rotation of the motor 101. Further, the motor 101 of the first embodiment is a three-phase permanent magnet synchronous motor. 102, 103, and 104 shown in FIG. 1 are windings provided in the motor 101. The motor 101 operates by the interaction between a magnetic flux generated from a permanent magnet provided in a rotor (not shown) and a magnetic field generated by a current flowing through windings 102, 103, 104 fixed to a stator (not shown). The currents Iu, Iv, and Iw flowing through the windings 102, 103, and 104 are U-phase current, V-phase current, and W-phase current, respectively. The currents Iu, Iv, and Iw are usually in the form of sinusoidal alternating currents that are 120 degrees out of phase with each other.

The motor 101 includes a temperature sensor 105. The temperature sensor 105 detects the temperature of the motor 101 and outputs a temperature sensor signal 106 indicating the detected temperature. The temperature sensor signal 106 is input to the controller 51. The controller 51 is an inverter circuit 1 based on information from each sensor including the temperature sensor signal 106 in order to give the motor 101 the torque required by the torque command 52 input from the vehicle controller 53 that controls the vehicle system. The currents Iu, Iv, and Iw are passed through the motor 101 to rotate the motor 101. The details of the processing of the controller 51 will be described later with reference to FIG.

The temperature sensor signal 106 is information necessary mainly for torque temperature compensation. Since the magnetic flux generated from the magnets constituting the rotor of the motor 101 is temperature-dependent, the relationship between the currents Iw, Iv, Iw flowing through the windings of the motor 101 and the torque generated in the motor 101 changes depending on the temperature. be.

Further, the motor 101 includes a rotation position sensor 107. The rotation position sensor 107 has a function of detecting the rotation position of the rotor of the motor 101 as a rotation angle. The rotation position sensor 107 outputs a rotation position sensor signal 108 indicating the detected rotation position. The rotation position sensor signal 108 is input to the controller 51. The processing of the rotation position sensor signal 108 in the controller 51 will be described later with reference to FIG.

The current sensors 109, 110, and 111 detect the current amounts of the currents Iu, Iv, and Iw, respectively, and output the current sensor signals 112, 113, and 114 based on the current amounts. The current sensor signals 112, 113, 114 are input to the controller 51. The processing of the current sensor signals 112, 113, and 114 in the controller 51 will also be described later with reference to FIG.

The inverter circuit 1 includes switching elements 2, 3, 4, 5, 6, 7 and freewheeling diodes 8, 9, 10, 11, 12, and 13.

The switching elements 2, 3, 4, 5, 6, and 7 of the first embodiment are IGBTs (insulated gate bipolar transistors), and include a gate terminal, a collector terminal, and an emitter terminal. The freewheeling diodes 8, 9, 10, 11, 12, and 13 are connected between the collector terminal and the emitter terminal of the switching elements 2, 3, 4, 5, 6, and 7. The freewheeling diodes 8, 9, 10, 11, 12, 13 are the freewheeling diodes 8, 9, 10, 11 when the collector terminals of the switching elements 2, 3, 4, 5, 6, and 7 have a higher potential than the emitter terminals. , 12, 13 is passed through, and the switching elements 2, 3, 4, 5, 6, and 7 are prevented from being subjected to a high reverse voltage.

Switching the on and off of the switching elements 2, 3, 4, 5, 6, 7 is performed by the gate drive signals 14, 15, 16, which are connected to the gate terminals of the switching elements 2, 3, 4, 5, 6, 7. Performed by 17, 18 and 19. The six gate signals 21 that are the basis of the respective gate drive signals 14, 15, 16, 17, 18, and 19 are generated and output by the controller 51. The gate signal 21 output from the controller 51 is input to the gate drive circuit 20.

The gate drive circuit 20 converts the gate signal 21 into the potential required for switching the switching elements 2, 3, 4, 5, 6, 7 on and off, and the gate drive signals 14, 15, 16, 17, 18, Output 19 is output. The generation of the gate signal 21 in the controller 51 will be described later with reference to FIG.

The emitter terminal of the switching element 2 and the collector terminal of the switching element 3 are connected, and the connection point is connected to the winding 102 to pass a current Iu. The emitter terminal of the switching element 4 and the collector terminal of the switching element 5 are connected, and the connection point is connected to the winding 103 to pass a current Iv. The emitter terminal of the switching element 6 and the collector terminal of the switching element 7 are connected, and the connection point is connected to the winding 104 to pass a current Iw. The collector terminals of the switching elements 2, 4 and 6 are commonly connected and connected to the high potential DC wiring 22. Further, the emitter terminals of the switching elements 3, 5 and 7 are commonly connected and connected to the low potential DC wiring 23.

As a result, the controller 51 turns on and off the switching elements 2, 3, 4, 5, 6, and 7 at appropriate timings based on the generated gate signal 21, and the current flowing through the windings 102, 103, 104. Iu, Iv, and Iw are controlled to realize the rotation control of the motor 101. Normally, the gate signal 21 forms a PWM (Pulse Width Modulation) signal so that the currents Iu, Iv, and Iw are sinusoidal signals having 120-degree phases different from each other.

The voltage sensor 25 is connected to the high-potential DC wiring 22 and the low-potential DC wiring 23, and detects the potential difference between them. Since the potential difference between the high-potential DC wiring 22 and the low-potential DC wiring 23 is usually a high voltage of 100 V or more, the voltage sensor 25 generates a DC voltage sensor signal 26 converted into a low voltage that can be detected by the controller 51. Output. The DC voltage sensor signal 26 is input to the controller 51.

The DC current sensor 27 detects the current flowing through the high-potential DC wiring 22. The DC current sensor 27 generates and outputs a DC current sensor signal 28 indicating the detected current. The DC current sensor signal 28 is input to the controller 51.

The smoothing capacitor 29 included in the inverter circuit 1 is connected between the high-potential DC wiring 22 and the low-potential DC wiring 23. The smoothing capacitor 29 has a function of suppressing the pulsation of the DC voltage generated by the switching operation of the switching elements 2, 3, 4, 5, 6, and 7.

In the battery 201, the terminal on the high potential side of the battery 201 and the high potential DC wiring 22 are connected, the terminal on the low potential side of the battery 201 and the low potential DC wiring 23 are connected, and power is supplied to the inverter circuit 1 and the motor 101. Works as a DC power source.

The contactor 202 is provided between the high potential side of the battery 201 and the high potential DC wiring 22. By operating the contactor 202 on and off, power transmission between the battery 201 and the inverter circuit 1 and its disconnection are realized. In the operation control of the contactor 202, a battery controller (not shown) operates on and off in response to a command from the vehicle controller 53.

FIG. 2 is a processing block diagram illustrating the processing of the controller 51 that controls the motor in the first embodiment shown in FIG.

The processing by the controller 51 is performed by the current command calculation unit 61, the current control unit 62, the two-phase three-phase conversion unit 65, the gate control signal calculation unit 66, the three-phase two-phase conversion unit 67, the position / speed calculation unit 68, and the DC voltage. The ascending determination unit 71 is included. The controller 51 flows three-phase currents Iu, Iv, and Iw through the motor 101 to control rotation, but inside the controller 51, the coordinates of the three-phase AC system are converted into two-phase coordinates represented by the d-axis and the q-axis. The so-called vector control method, which processes in the coordinate system, is used.

The processing of the controller 51 in the state where the contactor 202 is turned on and the battery 201 is connected to the inverter circuit 1 will be described.

The current command calculation unit 61 calculates the d-axis current command value Id * and the q-axis current command value Iq *. The d-axis current command value Id * and the q-axis current command value Iq * are calculated based on the torque command 52, the rotation speed ω, and the temperature sensor signal 106. The torque command 52 indicates the torque to be output by the motor 101. Generally, the torque T of the motor is expressed by the relation of the following equation (1) and depends on the current.

T = α (A ・ IQ + B ・ ID ・ IQ) ・ ・ ・ (1)
In the above equation (1), ID is the d-axis current, IQ is the q-axis current, α is the number of motor pole pairs, A is the magnetic flux of the magnet, and B is the inductance difference between the d-axis and the q-axis, which are constants determined by the motor. ..

The rotation speed ω is obtained by the position speed calculation unit 68 based on the rotation position sensor signal 108, and is output. Since the electromotive force induced from the windings 102, 103, 104 of the motor 101 changes according to the rotation speed ω, the rotation speed ω affects the current and is required for the calculation of the current command value.

The temperature sensor signal 106 is information necessary for temperature compensation of the current command value because the magnetic flux of the permanent magnet provided in the rotor of the motor 101 changes depending on the temperature and as a result affects the torque of the motor.

The position speed calculation unit 68 calculates the rotation speed ω and the magnetic pole position θd based on the rotation position sensor signal 108. The magnetic pole position θd is input to the two-phase three-phase conversion unit 65 and the three-phase two-phase conversion unit 67, and is used for conversion between the two-phase coordinates and the three-phase coordinates of the d-axis and the q-axis. The three-phase two-phase conversion unit 67 performs coordinate conversion of the current sensor signals 112, 113, 114 corresponding to the three-phase currents Iu, Iv, and Iw to the d-axis and q-axis based on the information of the magnetic pole position θd. The d-axis detection current Id and the q-axis detection current Iq are output.

The comparator 63 calculates the deviation between the d-axis current command value Id * output from the current command calculation unit 61 and the d-axis detection current Id output from the three-phase two-phase conversion unit 67, and calculates the d-axis current deviation ΔId. Is output.

The comparator 64 calculates the deviation between the q-axis current command value Iq * output from the current command calculation unit 61 and the q-axis detection current Iq output from the three-phase two-phase conversion unit 67, and the q-axis current deviation ΔIq. Is output.

The current control unit 62 performs feedback control so that the d-axis difference current ΔId and the q-axis current deviation ΔIq, which indicate the deviation between the command value which is the target value and the measured value which is the output value, become zero, and updates the output value. The d-axis voltage command Vd * and the q-axis voltage command Vq *, which are voltage commands, are calculated and output.

The current control unit 62 outputs the command value in the form of voltage because the gate signal 21 output from the gate control signal calculation unit 66 is a PWM signal that is more convenient to define the command by voltage. The feedback control in the current control unit 62 is performed by, for example, PI control.

Further, the current control unit 62 has a path for directly inputting the d-axis current command value Id * and the q-axis current command Iq * in order to realize feedforward control in which the command value is used as the output value as it is. The current control unit 62 may change the combination of feedback control and feedforward control depending on the conditions, and is also implemented in the embodiment of the present invention.

The d-axis voltage command value Vd * and the q-axis voltage command value Vq * output from the current control unit 62 are input to the two-phase three-phase conversion unit 65. The two-phase three-phase conversion unit 65 calculates three-phase voltage command values Vu *, Vv *, and Vw based on the input d-axis voltage command value Vd *, q-axis voltage command value Vq *, and magnetic pole position θd. ,Output.

The gate control signal calculation unit 66 generates six gate signals 21 which are PWM signals by comparing the three-phase voltage command values Vu *, Vv *, and Vw with a carrier carrier wave (not shown), and outputs the six gate signals 21 to the gate drive circuit 20. do.

The above is the normal processing of the controller 51. Next, the process according to the present invention will be described.

In the first embodiment, the DC voltage rise determination unit 71 is added to the processing of the controller 51. The DC voltage rise determination unit 71 inputs the DC voltage sensor signal 26 and detects a state in which the DC voltage rises, thereby determining that the connection of the contactor 202 has been released.

When the regenerative brake is operated while the vehicle is running, the electric power generated by the induced voltages of the windings 102, 103, 104 of the rotating motor 101 is charged to the battery 201 via the inverter circuit 1 and the connected contactor 202. It becomes a state. At this time, if the contactor 202 is released for some reason such as a malfunction, the electric power generated by the motor 101 is not charged in the battery 201 but is accumulated in the smoothing capacitor 29, and the voltage appearing in the DC voltage sensor signal 26 rises. Is detected. Therefore, sensing an increase in the DC voltage during power regeneration control can be a method for determining the connection opening of the contactor 202.

Further, as another determination method for opening the connection of the contactor 202, a battery controller (not shown) that monitors the execution of the connection of the contactor 202 and the connection state, and a vehicle controller 53 that instructs the battery controller to control the contactor 202 The state information of the contactor 202 may be sent to the controller 51 for monitoring.

When the connection of the contactor 202 is opened while the vehicle is in power regeneration control, the DC voltage rises, which may cause deterioration or failure of circuit components such as the smoothing capacitor 29 connected to the DC voltage. Therefore, in the present invention, there is a method of suppressing an increase in the DC voltage when the contact of the contactor 202 is opened and controlling the voltage to converge to the voltage before the opening to prevent failure of circuit components and enable the contactor 202 to be reconnected. show.

FIG. 3 shows an example of a control processing flow for detecting that the contactor 202 has been opened and for subsequent processing according to the first embodiment of the present invention.

Step S1 is a process of initializing the count value count. The count value count is used to indicate the passage of time.

Step S2 is a timer interrupt, and an interrupt is input every 125 μs, for example, based on a timer (not shown) inside the controller, and the process proceeds to the next step.

In step S3, the DC voltage rise determination unit 71 compares the voltage threshold value V1 (for example, 840V) set in advance with the DC voltage information obtained from the DC voltage sensor signal 26. If the DC voltage information is equal to or less than the voltage threshold value V1, the process returns to step S1 and the count value count is initialized. If the DC voltage information exceeds the voltage threshold value V1, the process proceeds to step S4 and the count value count is incremented by one. The reason why the DC voltage information exceeds the voltage threshold V1 is not the superposition of noise, but as a method for obtaining the certainty that the voltage rise is the reason. Detects that it exceeds.

Step S5 detects whether or not the DC voltage information in step S3 exceeds the voltage threshold value V1 until the number of times the count value incremented in step S4 reaches a predetermined value (3 in the first embodiment). When the count value count reaches a predetermined value in step S5, it is detected that the DC voltage information exceeds the voltage threshold value V1 for 125 μsec × 3 = 375 μsec, and it is determined that the connection of the contactor 202 is released. The above steps S1 to S5 are the processes performed by the DC voltage rise determination unit 71 in FIG. The DC voltage rise determination unit 71 outputs the determination result 72. The determination result 72 corresponds to the determination result output in step S5 of FIG.

If it is determined that step S5 is YES, the process proceeds to step S6. In the process of step S6, the q-axis current command Iq * is forcibly set to a predetermined fixed value in the current command calculation unit 61. FIG. 2 schematically represents this process, and a q-axis current command fixed value setting 73 is provided inside the current command calculation unit 61. The current command calculation unit 61 connects the q-axis current command fixed value setting 73 and the q-axis current command Iq * output by the current command calculation unit 61 via a switch 74. The on / off operation of the switch 74 is controlled by the determination result 72 output from the DC voltage rise determination unit 71. Further, although the process of step S6 is not shown, the current control unit 62 mainly performs feedforward control in which the q-axis current command Iq * is directly input, and feedback control by the q-axis current deviation ΔIq is not performed. Alternatively, reduce the proportion involved in current control. Further, the q-axis current command value Iq * set in the q-axis current command fixed value setting 73 is set in advance so that the current flowing through the DC bus becomes 0 A. Since the specific set value differs depending on the characteristics of the vehicle system, it will be obtained by experiments or the like, but it will be a value close to Iq * = 0A.

Similar to step S2, step S7 is for determining the DC voltage of the next step S8 at a periodic timing.

Step S8 detects whether the DC voltage information is lower than the voltage threshold value V2. When the increase in the DC voltage is stopped by the control in step S6, the DC voltage maintains the voltage exceeding the voltage threshold value V1. When the contactor 202 changes from the open state (off) to the connected state (on) in that state, the DC voltage approaches the electromotive force of the battery 201, so that the voltage drops. In step S8, the voltage threshold value V2 is set lower than the voltage threshold value V1 (for example, 820V) in order to increase the probability that the voltage drop has occurred in consideration of the influence of noise superposition, and it is determined that the contactor 202 is reconnected. .. If the DC voltage does not drop below the voltage threshold V2, the process returns to step S7, and at the next predetermined timing, the process proceeds to step S8 and the DC voltage comparison is repeated.

If it is determined in step S8 that the contactor 202 is reconnected, the process proceeds to step S9, and the q-axis current command value Iq * output from the current command calculation unit 61 is also used for the torque command 52 before the contactor 202 is released. Returns to the value calculated in. In FIG. 2, this process corresponds to outputting the determination result 72 by the DC voltage rise determination unit 71, turning off the switch 74, and returning the process of the current command calculation unit 61 to the conventional calculation.

FIG. 4 is a timing diagram illustrating each signal and state in the processing of the controller 51 according to the first embodiment of the present invention. This is an example in which the connection of the contactor 202 is released during the regenerative operation of the vehicle, and then the contactor 202 is reconnected.

The time T0 is the timing at which the DC voltage rise determination unit 71 senses that the DC voltage sensor signal 26 has a voltage higher than the voltage threshold V1. In the period before the time T0, the DC current sensor signal 28 has a current of 250 A flowing from the inverter circuit 1 toward the battery 201 due to the regenerative operation. Here, when the DC current sensor signal 28 takes a negative value, it is defined as a regenerative operation, and when it takes a positive value, it is defined as a power running operation in which a current flows from the battery 201 to the inverter circuit 1.

In the period before the time T0, the q-axis current Iq flows according to the current value (-100A in this embodiment) specified in the q-axis current command value Iq *. Further, the d-axis current command value Id * is set to a predetermined current value (-100A in the first embodiment) in order to obtain a predetermined regenerative current. The voltage of the DC voltage sensor signal 26 rises immediately before the time T0. The moment when this voltage rise occurs is assumed to be the moment when the connection of the contactor 202 is released.

The determination by the DC voltage rise determination unit 71 that the connection of the contactor 202 has been released is determined by the DC voltage sensor signal 26 for a certain period by the timer inside the controller as shown in steps S2 to S5 of the processing flow shown in FIG. After confirming that the voltage threshold value V1 is continuously exceeded, the control processing method is changed.

The time T1 is the timing when the DC voltage rise determination unit 71 determines that the connection of the contactor 202 is released. During the period from time T0 to time T1, the regenerated current flows into the smoothing capacitor 29, and the voltage applied across the smoothing capacitor 29 becomes high. Therefore, in order to protect the element, for example, in order to keep the voltage applied to the smoothing capacitor 29 below the withstand voltage thereof, it is necessary to appropriately set the period from the time T0 to the time T1. In this embodiment, as shown in FIGS. 3 and 4, the clock inside the controller 51 (125 μs cycle in the first embodiment) and the number of counts (3 counts in the first embodiment) are used from time T0 to time T1. Although the period is determined, it should be set appropriately in consideration of the withstand voltage of the circuit element to be used.

When it is determined that the connection of the contactor 202 is released at the time T1, the q-axis current command value Iq * is forcibly set to a fixed value close to 0A (0A in the first embodiment). As a result, the q-axis current Iq is controlled to converge to 0A. The d-axis command value Id * is calculated by the current command calculation unit 61 so as to suppress the induced voltage of the windings 102, 103, 104 of the motor 101. The d-axis current command value Id * tends to have a higher current value than the value at the time of regenerative operation before the time T1. As a result, the voltage rise of the DC voltage sensor signal 26 subsides after the time T1, and the DC current sensor signal 28 converges to almost zero.

The time T2 is the timing when it is determined that the contactor 202 is connected again. When the contactor 202 is reconnected immediately before the time T2, the voltage of the DC voltage sensor signal 26 drops sharply and approaches the electromotive force of the battery 201. Therefore, the DC voltage rise determination unit 71 detects that the voltage of the DC voltage sensor signal 26 is lower than the voltage threshold V2 at the timing of the time T2, and determines that the contactor 202 has been reconnected. Then, as described earlier in step S9 of FIG. 3, the DC voltage rise determination unit 71 cancels the forced setting of the q-axis current command value Iq * and returns to the conventional control. In the example of FIG. 4, after determining the reconnection of the contactor 202, the q-axis current command value Iq * is smoothly changed without suddenly returning to the original set value (here, −100A). This suppresses sudden torque fluctuations and realizes smooth operation of the vehicle.

The method shown in Example 1 makes it possible to determine whether to open or reconnect the contactor 202, and it is possible to continue the torque control of the motor while suppressing the increase in the DC voltage while the contactor 202 is open. Reconnection of the contactor 202 can be easily realized.

According to the first embodiment, even when the contactor 202 is in the open state, the torque control of the motor 101 can be continued while suppressing the overvoltage. Therefore, the torque control of the motor 101 is continued even if the contactor 202 is reconnected. Is possible.

(Example 2)
The second embodiment is another example in which the same effect as that of the first embodiment is obtained, and is an example considering a case where the increase in the DC voltage does not stop due to an error included in the output value of the sensor.

FIG. 5 is a processing block diagram illustrating the processing of the controller 51 that controls the motor according to the second embodiment of the present invention. FIG. 6 is a processing flow diagram showing the processing procedure. The processing block of the controller 51 in FIG. 5 will be described focusing on a configuration different from that of FIG.

The torque command 52 output from the vehicle controller 53 is input to the 0-side terminal of the selector 84. The contactor open torque command 83, which is characteristic of the second embodiment, is connected to the other one terminal of the selector 84.

A method of generating the torque command 83 when the contactor is open will be described. The DC current setting 80 is a setting of the target DC current, and is set to, for example, 0A. The comparator 81 compares the input DC current setting 80 with the DC current sensor signal 28, and outputs the DC current deviation ΔIdc. The PI control unit 82 inputs a DC current deviation ΔIdc, performs feedback control of PI control so that the DC current deviation ΔIdc becomes 0, and outputs a torque command 83 when the contactor is open in the form of a torque command.

As described in FIG. 2, the DC voltage rise determination unit 71 determines whether or not the connection of the contactor 202 is opened as a result of detecting the voltage of the DC voltage sensor signal 26, and determines whether the contact is open or not as the determination result 72 in the selector 84. Output.

The selector 84 is normally (when the DC voltage rise determination unit 71 does not determine that the connection of the contactor 202 is released), the switch is pushed down to the 0 side terminal (connected to the 0 side terminal), and is output from the vehicle controller 53. The torque command 52 is input to the current command calculation unit 61 as an internal torque command 85 incorporated inside the controller 51, and motor control in a normal state is executed.

When the DC voltage rise determination unit 71 determines that the connection of the contactor 202 is released, the switch of the selector 84 is pushed down to the 1-side terminal (connected to the 1-side terminal) by the output of the determination result 72. As a result, the torque command 83 when the contactor is open is selected by the selector 84 and input to the current command calculation unit 61 as the internal torque command 85.

From the above configuration, when it is determined that the connection of the contactor 202 is released, the PI control unit 82 calculates the torque command value so that the DC current sensor signal 28 becomes 0A, and the torque command when the contactor is opened, which is the calculation result, is calculated. A feedback control system is formed by inputting 83 as a torque command to the current command calculation unit 61. As a result, the DC current is controlled to 0, the current flowing into the smoothing capacitor 29 also converges to zero, and an increase in the voltage applied thereto can be prevented.

FIG. 6 showing a processing flow corresponding to the configuration of FIG. 5 will be described. Steps S1 to S5 are exactly the same as the processing flow of FIG. 3 described above, and are processing for determining that the connection of the contactor 202 is released by the DC voltage rise determination unit 71.

When the release of the contactor 202 is determined in step S5 and the process proceeds to YES, the contactor opening torque command 83 generated by the PI control unit 82 so that the DC current becomes 0 in step S10 is input to the current command calculation unit 61. Applies to the internal torque directive 85 to be applied.

Steps S7 and S8 after step S10 are exactly the same as the processing flow of FIG. 3 described above, and are processing for determining that the contactor 202 is reconnected by the DC voltage rise determination unit 71.

When the reconnection of the contactor 202 is determined in step S8 and the process proceeds to YES, the selector 84 is tilted to the 0-side terminal (connected to the 0-side terminal) in step S11, and the motor control is performed based on the normal torque command 52. Will be implemented.

By the method shown in the second embodiment, it is possible to determine whether the contactor 202 is connected or reconnected, and the torque control of the motor 101 can be continued after suppressing the increase in the DC voltage during the period when the contactor 202 is open. , The contactor 202 can be easily reconnected. Further, by setting the control target to the DC current, the current flowing through the smoothing capacitor 29 can be controlled more directly, so that it is possible to perform accurate control excluding the influence of errors of sensors other than the DC current sensor 27. ..

(Example 3)
Example 3 is an example relating to vehicle control carried out together with the processing of Example 1 and Example 2. When the first and second embodiments are carried out when the connection of the contactor 202 is released, the braking torque generated by the regenerative control until now is almost eliminated. As a result, the speed of the vehicle slows down immediately after the contact of the contactor 202 is opened, so that the driver of the vehicle may feel a sense of discomfort because the braking method is weakened.

Therefore, in the third embodiment, in addition to the processing performed in the first and second embodiments when the connection of the contactor 202 is released, the processing for compensating for the insufficient braking torque due to the regenerative control by the friction brake is performed.

FIG. 7 illustrates Example 3 by adding components to the configuration example of the motor control system for driving the vehicle with the motor of FIG. 1 described above.

The required braking force 91 is information on the braking force required by the driver for the vehicle, which is detected when the driver depresses the brake pedal. The vehicle controller 53 to which the required braking force 91 is input performs a calculation in which the regenerative / friction brake coordinated control unit 92 contained therein appropriately distributes the required braking force into the regenerative braking amount and the friction braking amount. The required brake amount is required for the controller 51 that controls the regenerative control by the motor 101 and the brake controller 96 that controls the mechanical brake.

The brake controller 96 has a friction brake control unit 97 that performs arithmetic processing. The friction brake control unit 97 calculates a control amount suitable for the characteristics of the mechanical brake provided in the vehicle (not shown) based on the friction brake requirement value 98 input from the regenerative / friction brake cooperative control unit 92, and the brake controller 96. A mechanical brake is operated through the brake to generate a braking force due to friction.

The controller 51 has a braking force calculation unit 93. The braking force calculation unit 93 communicates with the regenerative / friction brake cooperative control unit 92. The regenerative / friction brake coordinated control unit 92 outputs the regenerative brake required value 94 to the braking force calculation unit 93. On the other hand, the braking force calculation unit 93 outputs the regenerative brake status 95 to the regenerative / friction brake coordinated control unit 92.

Here, an example of the form of the regenerative brake required value 94 and the regenerative brake status 95 will be given. The regenerative / friction brake coordinated control unit 92 transmits information on the required brake amount to the braking force calculation unit 93 as the regenerative brake required value 94. Upon receiving this, the braking force calculation unit 93 sets the information on the currently generated regenerative braking force and the information on the maximum possible regenerative braking force determined from the current state as the regenerative braking status 95, and the regenerative / friction brake coordinated control unit 92. Send to. Based on this information, the regenerative / friction brake coordinated control unit 92 obtains an appropriate required amount of braking force to be distributed to the braking force calculation unit 93 and the friction brake control unit 97.

As an example of appropriate braking force distribution, if the currently generated regenerative braking force does not reach the maximum regenerative braking force that is possible and the required braking force 91 is larger than the maximum regenerative braking force, the maximum regenerative energy is recovered. For the purpose, the regenerative / friction brake coordinated control unit 92 sets the regenerative brake required value 94 to a value corresponding to the maximum possible regenerative braking force, and the amount obtained by subtracting the regenerative brake required value 94 from the required braking force 91 is the friction brake. It is possible to set the required value to 98.

Further, the vehicle controller 53 updates the torque command 52 output to the controller 51 together with the regenerative brake request value 94 calculated based on the regenerative brake status 95.

Here, a case where the connection of the contactor 202 shown in the first and second embodiments is opened will be described. When the connection of the contactor 202 is opened, in the present invention, the q-axis current Iq is controlled to be zero. At this time, as shown in the equation (1), no torque is generated in the motor 101, and the braking torque becomes zero. In this case, the maximum possible regenerative braking force included in the regenerative braking status 95 transmitted from the braking force calculation unit 93 to the regenerative / friction brake cooperative control unit 92 is set to zero. Based on this, the regenerative / friction brake coordinated control unit 92 distributes the amount obtained by subtracting the current regenerative braking amount included in the regenerative brake status 95 from the required braking force 91 requested by the driver to the friction brake required value 98. , The regenerative braking requirement value 94 is set to zero. By the above processing, the braking torque does not change suddenly even if the contactor 202 is opened, and the driver does not feel uncomfortable when the vehicle is running.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations.

Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment.

Further, it is possible to add / delete / replace a part of the configuration of each embodiment with another configuration.

Further, each of the above configurations, functions, processing units, processing means and the like may be realized by hardware by designing a part or all of them by, for example, an integrated circuit.

Further, each of the above configurations, functions, and the like may be realized by software by the processor interpreting and executing a program that realizes each function.

1 ... Inverter circuit, 2, 3, 4, 5, 6, 7 ... Switching element, 29 ... Smoothing capacitor, 51 ... Controller, 52 ... Torque command, 53 ... Vehicle controller, 101 ...・ ・ Motor, 201 ・ ・ ・ Battery, 202 ・ ・ ・ Contactor

Claims (2)

A motor that generates the driving force of the vehicle and
An inverter circuit that is composed of switching elements and drives the motor,
A battery connected to the inverter circuit and supplying electric power to drive the motor,
A capacitor connected between the battery and the inverter circuit,
A contactor connected between the battery and the capacitor,
When the contactor is off, a control unit that allows a current to flow between the inverter circuit and the motor so that the voltage between the inverter circuit and the motor approaches the voltage applied to the capacitor side.
Equipped with
The control unit vector-controls the motor and controls the motor.
The control unit
A voltage sensor that detects the voltage across the capacitor and
A current sensor that detects the current flowing on the high potential side of the battery, and
A feedback control unit that calculates and outputs a torque command that brings the current detected by the current sensor closer to the target current, and
A current command calculation unit that outputs the q-axis current command value and d-axis current command value of vector control,
Have,
When the voltage detected by the voltage sensor is equal to or less than the first threshold voltage, the current command calculation unit calculates the d-axis current command value and the q-axis current command value based on the torque command input from the outside. When the voltage detected by the voltage sensor is equal to or less than the first threshold voltage and then exceeds the first threshold voltage, the d is based on the torque command output by the feedback control unit. The axis current command value and the q-axis current command value are calculated and output, and after the voltage detected by the voltage sensor exceeds the first threshold voltage, the voltage is lower than the first threshold voltage and is lower than the second threshold voltage. A vehicle control device characterized in that when it becomes low, the d-axis current command value and the q-axis current command value are calculated and output based on a torque command input from the outside. In the vehicle control device according to claim 1,
The brake part that generates the braking force of the vehicle by friction,
A friction brake control unit that controls the braking force of the brake unit,
The braking force calculation unit that obtains the current regenerative braking force,
A regenerative / friction brake coordinated control unit that outputs the braking force of the brake unit controlled by the friction brake control unit to the friction brake control unit based on the regenerative braking force obtained by the braking force calculation unit.
A vehicle control device characterized by further comprising.

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