JP3145313B2 - Electric vehicle control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric vehicle control device for controlling the driving of an electric vehicle using a permanent magnet type synchronous motor.

[0002]

2. Description of the Related Art In an electric vehicle driving device including a battery, an inverter, a motor, a control device, and the like, a permanent magnet type synchronous motor having high efficiency in terms of one charge traveling distance and the like is used. In addition, motors are becoming smaller and lighter in order to reduce the weight of electric vehicles, and motors are of high-speed rotation type in order to obtain high output. The control device is constituted by a microcomputer or the like, and employs a system in which the current is divided into a torque component current iq and an excitation component current id by vector control according to a torque command. When the permanent magnet type synchronous motor is rotated to a high rotation speed, the voltage generated at the motor terminal becomes extremely high due to the electromagnetic induction phenomenon, and exceeds the voltage that can be output from the inverter. For this reason, the control device sets the excitation component current id
A control method is used in which field weakening control is performed to make the negative value, and the induced voltage generated by the motor is reduced.

When a key switch of an electric vehicle is turned on,
A low-voltage control power supply is applied to the control device.
The control of the electric vehicle control device is started as follows. Upper arm (+ side) and lower arm on the input side of the inverter
A smoothing capacitor is connected between the (-) sides, and is charged to the same voltage as the battery before starting switching of the inverter. When the main relay (inverter relay) that connects the battery and the inverter is turned on, a large charging current flows through the smoothing capacitor, and the main relay and the connection circuit are broken.Therefore, a current limiting resistor connected in parallel with the main relay is connected in series. The connected auxiliary relay is turned on, and after the smoothing capacitor is charged to the same voltage as the battery, the main relay is turned on. Then, the auxiliary relay turns off. Then, switching of the inverter is started, and control of the motor current according to the torque command is started. The structure of the main relay, the auxiliary relay, and the current limiting resistor is disclosed in Japanese Patent Application Laid-Open No. 4-275002.

Next, consider a case where a driver turns off a key switch while an electric vehicle using a permanent magnet type synchronous motor is running. When the key switch is turned off, the control power is not applied to the control device, the main relay is turned off, and the switching of the inverter stops. Permanent magnet synchronous motors generate an induced voltage at the motor terminals in proportion to the rotation speed.When the motor line voltage becomes higher than the voltage of the smoothing capacitor, a current flows through the diode in the inverter to the smoothing capacitor. The smoothing capacitor is charged to the motor line voltage.

In particular, when the key switch is turned off during high-speed running, the line voltage of the motor (= the voltage across the smoothing capacitor) is much higher than that of the battery. When the switch is turned on and the auxiliary relay is turned on as usual (when the electric vehicle is stopped), an excessive current larger than that allowed by the current limiting resistor flows due to the high capacitor voltage. In some cases, the resistor may be destroyed, or an overcharge current may flow through the battery, thereby damaging the battery. For this purpose, Japanese Patent Application Laid-Open No. 7-8
Japanese Patent Application Laid-Open No. 7605 provides a determination means for determining whether the induced voltage of the motor is in a state in which an overcharge current can flow to the battery, in preparation for the case where the key switch is turned off and the field weakening control is stopped. For example, even if the key switch is turned off, the main relay is not turned off and the operation of the control device is not stopped.

[0006]

However, consider the case where the electric vehicle is traveling on a long downhill. The speed at which the driver turns off the key switch is 20km when the driver starts to descend.
/ h. Obviously, since the field for field weakening control is not performed, the control power supply is turned off, and thereafter, the above-described determination of the overcharged state cannot be performed. Therefore, the main relay is turned off, the motor control stops, and the operation of the inverter also stops. Then, without stepping on the brake, the electric vehicle travels downhill and is gradually accelerated, and when the speed becomes 100 km / h or more (field weakening control region), the induced voltage generated by the permanent magnet type synchronous motor becomes high. Thus, current flows through the diode in the inverter to the smoothing capacitor, and the voltage across the smoothing capacitor is charged to a higher voltage than the battery. Here, when the key switch is turned on, the auxiliary relay is also turned on, so that a very large capacitor voltage may damage components such as a current limiting resistor and a battery.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electric vehicle control device capable of avoiding damage to components due to unnecessary accumulated charge of a capacitor generated when a relay circuit is opened during running.

[0008]

The electric vehicle control device according to the present invention which achieves the above object is characterized by a relay circuit for opening and closing the power supply of a battery, and a capacitor provided at a subsequent stage of the relay circuit and connected in parallel to the battery. And an inverter at the subsequent stage of the capacitor for supplying the electric power of the battery to the permanent magnet synchronous motor; and a power supply control for the relay circuit, and thereafter, the motor of the permanent magnet synchronous motor using the inverter. An electric vehicle control device including a controller that executes control, wherein the controller turns on the power of the capacitor that is induced and accumulated by the permanent magnet synchronous motor when the relay circuit is opened. Prior to the control and the restart of the motor control, the preceding control consumed by the permanent magnet type synchronous motor is executed. And then shifting to the power-on control and the motor control.

Another feature is that a relay circuit comprising a main relay, an auxiliary relay and a resistor connected in parallel to the main relay for opening and closing the power supply of the battery, and a relay circuit provided at a subsequent stage of the relay circuit and connected in parallel to the battery And a power supply control of the relay circuit that turns on the main relay after the auxiliary relay. And thereafter controlling the power supply of the inverter by outputting a control signal, and a controller that executes a motor control, comprising: a means for measuring a terminal voltage of the capacitor, The controller includes means for monitoring the input of the terminal voltage, and a torque component current iq for controlling the motor. Run the preceding motor control to a value corresponding to the difference between the voltage and the predetermined voltage, and the terminal voltage to the predetermined voltage corresponding, in a means for transition to the power-on control of the relay circuit.

Another feature is that the controller has means for measuring a terminal voltage of the capacitor, and means for measuring a rotation speed of the permanent magnet type synchronous motor. Means for input monitoring the rotation speed, and means for shifting to power-on control of the relay circuit if the rotation speed is equal to or less than a predetermined rotation speed,
If the rotation speed exceeds a predetermined rotation speed, a preceding motor control is performed in which the torque component current iq of the motor control is set to a value corresponding to a difference between the terminal voltage and the predetermined voltage, and the terminal voltage is made equivalent to the predetermined voltage. Means for shifting to power-on control of the relay circuit.

Further, another feature is that a relay circuit for opening and closing the power supply of the battery is constituted by a main relay, an auxiliary relay and a resistor connected in parallel to the main relay, A capacitor connected in parallel, an inverter at a subsequent stage of the capacitor for supplying power from the battery to the permanent magnet type synchronous motor, and powering on the relay circuit for turning on the main relay after the auxiliary relay Take control,
And a controller that outputs a control signal to control the power supply of the inverter to execute motor control of the permanent magnet synchronous motor. The controller executes means for monitoring the input of the input current, and a preceding motor control for setting a torque component current iq of the motor control to a value corresponding to the input current, and sets the input current to 0 (zero). Correspondingly, means for shifting to power-on control of the relay circuit.

Alternatively, another feature is that the controller sets the torque component current iq of the motor control to 0.
The present invention is characterized in that there is means for shifting to power-on control of the relay circuit while executing the preceding motor control to be (zero).

According to the present invention, unnecessary accumulated charges are consumed in advance, so that damage to components can be avoided.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment according to the present invention.
It is a figure showing the electric vehicle control device of an example. The electric vehicle control device in the figure is a relay circuit including a relay 2 as a main relay (referred to as an inverter relay in this embodiment), an auxiliary relay 3 and a resistor 4 as a current limiting resistor, and a capacitor as a smoothing capacitor. 5, consisting of an inverter 6, and a controller 9.

[0015] The electric vehicle control device may be a current sensor.
8, a motor 7 serving as a permanent magnet type synchronous motor that inputs signals from various sensors such as an encoder 10, a magnetic pole position sensor 11, controls power supply from the battery 1, and drives a driving wheel 13 via a differential gear 12. Is controlling the output. The electric vehicle includes a battery 1, an electric vehicle controller, a motor 7, various sensors, a differential gear 12, driving wheels 13, a key switch 23, and the like. On the other hand, the controller 9 includes an id * command value calculation unit 14 that is an excitation component current, an iq * command value calculation unit 15 that is a torque component current,
It comprises a capacitor voltage determination section 16, a relay input section 17, a current command switching section 18, a capacitor voltage control section 19, a torque shock absorption processing section 20, a current control processing section 21, and a PWM output stop section 22.

During normal running, the battery 1 and the inverter 6
Is connected to the relay 2 and the capacitor 5. The inverter 6 is controlled by a PWM signal output from the controller 9, and supplies (applies) electric power (voltage) to the motor 7. The current flowing through the motor 7 is detected by the current sensor 8 and taken into the controller 9. The rotation speed of the motor 7 is detected by the encoder 10, and the magnetic pole position sensor 11 detects the magnetic pole position of the motor 7, and these are taken into the controller 10. The torque of the motor 7 is transmitted to drive wheels 13 through a differential gear 12.

When the key switch 23 of the electric vehicle is turned on, a control power is applied to the controller 9 and the control in the controller 9 is started. Similarly, by turning off the key switch, the controller
The power is not applied to 9 and the control operation in the controller 9 stops.

In the configuration of the electric vehicle control device shown in FIG. 1, in a normal state (when the electric vehicle is started from a stop), the "power-on control of the relay circuit" is performed as follows. First, when the driver turns on the key switch 23, a control power supply (not shown) is applied to the controller 9. The controller 9 turns on the auxiliary relay 3 first if the vehicle is in a state where the vehicle can travel after performing abnormality diagnosis or the like of the control device. Before the auxiliary relay 3 is turned on, the voltage of the capacitor 5 is 0 (zero). When the auxiliary relay 3 is turned on, the capacitor 5 is charged to the voltage of the battery 1. Since the current limiting resistor 4 is connected in series to the auxiliary relay 3, the maximum value of the current flowing through the circuit is determined by the voltage of the battery 1 and the size of the resistor 4, and the current is determined by the resistor 4 and the capacitor 5 It gradually decreases to 0 (zero) with a time constant determined from.

The capacity of the resistor 4 can be determined from the maximum value of the current and the time constant of the circuit as a value that does not cause the resistor 4 to burn out. Although it depends on the heat dissipation method of the resistor 4, if the allowable current is about 10 times the allowable current determined by the capacitance, it is considered that the current can flow for several tens of ms. When the voltage of the capacitor 5 becomes the same as that of the battery 1, the relay 2 is turned on and the auxiliary relay 3 is turned off.

Thereafter, the controller 9 starts “motor control” to be described later, fetches a motor current value from the current sensor 8 to calculate current control, and sends a voltage command to the inverter 6 by PWM.
Output as a signal. The control of the motor 7 is performed by vector control, and the excitation current id is determined from the motor rotation speed and the torque command, and the torque current iq is determined from the excitation current id and the torque command. In areas where the motor speed is high,
In order to reduce the induced voltage of the permanent magnet synchronous motor, field weakening control in which the exciting current id is negative is generally performed.

In the configuration of the electric vehicle control device shown in FIG. 1, normal "motor control" is executed as follows.
First, the torque command value TRQ is stored in the torque shock absorption processing unit 20.
Is input to Here, it is assumed that the torque command value TRQ is determined according to the amount of depression of the accelerator and the brake.
In the “motor control”, the torque shock absorption processing unit 20
Without performing any processing, the torque command value TRQ from the external microcomputer or the like is directly used as the torque command value TRQ ′, and the torque command value TRQ ′ is transmitted to the id * command value calculation unit 14 and the iq * command value calculation unit 15. Output. Separately, the rotation speed ω of the motor 7 is calculated from the signal of the encoder 10, and the magnetic pole position θ of the motor 7 is calculated from the signal of the magnetic pole position sensor 11.

The id * command value calculator 14 calculates an exciting component current command value id * from the torque command value TRQ and the motor speed ω. The iq * command value calculation unit 15 calculates a torque component current command value iq * from the torque command value TRQ and the current command value id *. The current iu, iv, iw flowing through the motor 7 is detected from the current sensor 8. The current control processing unit 21 includes a current command value id * calculated by the id * command value calculation unit 14 and a current command value calculated by the iq * command value calculation unit 15.
The motor current is controlled using iq * as the command value, and the PWM signal
Create Pu, Pv, Pw. Normally, the PWM output stop unit 22
Signal output is permitted and output to inverter 6.
As a result, the torque of the motor 7 is controlled to the torque command value TRQ and transmitted to the drive wheels 13. In this way, the electric vehicle can run at an arbitrary speed when the driver operates the accelerator and the brake.

Next, in the configuration of the electric vehicle control device described above, when the electric vehicle is traveling at high speed on a downhill, the driver turns off the key switch 23 and turns off the controller 9. Consider the case. In this case, the controller 9 stops the control, and the relay 2 is disconnected (the auxiliary relay 3 is originally disconnected). If the driver notices and the key switch 23 is turned on again,
A method for returning to normal running will be described below. That is, the operation of the controller 9, such as the capacitor voltage determination unit 16, the relay input unit 17, the switching unit 18, the capacitor voltage control unit 19, and the torque shock absorption processing unit 20, will be described.

When the rotation speed of the motor 7 is high, the motor control performs control to suppress the induced voltage of the motor 7 by performing field weakening control. However, since the field-weakening control is also stopped by temporarily stopping the motor control, a high induced voltage is generated in the motor 7 when the rotation speed of the motor 7 is high. Therefore, when the key switch 23 is turned off, the power of the controller 9 is turned off, the relay 2 is turned off, and the output of the PWM signals Pu, Pv, Pw is stopped, the terminal of the capacitor 5 is The voltage Vc is charged to a high voltage. This voltage Vc is equal to the line voltage of the permanent magnet type synchronous motor, and may be higher than the battery voltage VB by 100 V or more.

In such a state, when the key switch 23 is turned on again and the controller 9 is started, before the relay 2 is operated following the auxiliary relay 3, first, the capacitor voltage judging section 16 firstly sets the battery as a predetermined voltage. The voltage difference between the voltage and the terminal voltage Vc of the capacitor 5 is determined. The predetermined voltage used for this determination is a predetermined minimum guaranteed voltage VB ₀ (or a battery nominal voltage or a reference voltage) of the battery 1 or an actual voltage VB of the battery 1.

The actual voltage VB of the battery 1 is measured using a battery voltage sensor (not shown) directly connected to the battery 1 or obtained from communication information from a microcomputer that manages charging of the battery. Can be. Alternatively, the terminal voltage of the capacitor 5 measured by the terminal voltage measuring means of the controller 9 is determined as the battery voltage VB when the electric vehicle is running, particularly when the relay 2 is turned on and the torque command is 0. The value stored in the memory of the controller 9 may be used. Even if the voltage Vc of the capacitor 5 is lower than the voltage VB of the battery 1, if the motor 7 is rotating, the voltage Vc of the capacitor 5 can be made equal to the battery voltage VB by regenerative charging.

Then, in the capacitor voltage judging section 16, the voltage Vc of the capacitor 5 is changed to the minimum guarantee voltage V as a predetermined voltage.
Whether exceeds the B ₀ or battery voltage VB is determined. The capacitor voltage Vc is not high (Vc ≦ VB ₀ or VB)
At times, the flag ryon is set (output), and the relay closing process is executed. That is, the relay input unit 17 turns on Ry2 to turn on the auxiliary relay 3, and turns on Ry1 to turn on relay 2 after a certain period of time when it is expected that the voltage of the capacitor 5 and the voltage of the battery 1 will be equal. Then, the "relay circuit power-on control" operation of turning off Ry2 and disconnecting the auxiliary relay 3 is executed.

Then, the PWM output stopping unit 22 outputs the PWM signal P
A “motor control” operation of permitting output of u, Pv, and Pw is executed. Note that a method of actually measuring the voltage of the capacitor 5 and confirming that the voltage becomes equal to the voltage of the battery 1 and then turning on Ry1 and turning on the relay 2 is also conceivable. Also,
The above-described “power-on control of the relay circuit” and “motor control” of the PWM output stop unit may be the same as those in the related art.

On the other hand, when it is determined to be above (Vc> VB ₀ or VB) is a flag Vccont (output) capacitor voltage control unit 19, the minimum guaranteed voltage as a predetermined voltage
VB ₀ or battery voltage VB (actual battery 1 voltage VB)
Motor control that equalizes the voltage Vc of the capacitor 5
The capacitor voltage control process is executed. That is, when the flag Vccont is set, the capacitor voltage control unit 19 outputs the current command value for performing the capacitor voltage control of lowering the voltage Vc of the capacitor 5 which is higher to be equal to or less than the battery voltage VB. iq * '. And the switching unit 18 is also the iq * command value calculation unit 1
Instead of the current command value iq * calculated in 5, the current command value iq * '
Is selected, and capacitor voltage control is performed to lower the terminal voltage of the capacitor to a value equivalent to a predetermined voltage. Note that the expression “corresponding to the predetermined voltage” indicates that the voltage Vc may not be equal to the predetermined voltage as long as the voltage Vc falls within a voltage range where no harm occurs.

On the other hand, the torque shock absorption processing section 20 sets the torque command value TRQ 'to 0. The id * command value calculation unit 14 calculates a current command value id * when the torque command value TRQ 'is 0 in a field weakening region in a high rotation region according to the motor rotation speed ω. The PWM output stop unit 22 permits the output of the PWM signals Pu, Pv, Pw, and the current control processing unit 21 executes the current control according to the current command values iq * ', id *.

As described above, the electric charge once charged in the capacitor 5 is given a current command value iq * ', so that a positive torque current flows to the motor 7 and is consumed as a torque. Terminal voltage can be reduced. Also, by executing the field-weakening control that has been stopped regardless of the turning on of the relay circuit, the induced voltage generated in the motor 7 is suppressed, and the line voltage is the maximum voltage that the inverter can output (≒ the battery voltage). It can also be as follows. By performing such control, the motor 7
No unlimited current flows from the capacitor 5 to the capacitor 5.

When the capacitor voltage determination unit 16 determines that the charge stored in the capacitor 5 has been discharged and the voltage Vc has become substantially equal to the battery voltage VB, the capacitor voltage control unit 19 Current command value iq
Set * 'to 0 to stop capacitor voltage control. The current control processing unit 21 performs current control according to the current command values iq * ', id *. Then, the torque current value iq is equal to the command value iq * '
At the point of time equal to (= 0) or at the point in time when a predetermined time of a predetermined current response has elapsed, the capacitor voltage control unit 19 sets the flag ryon and outputs permission to start the relay-on process.

Here, when the capacitor voltage control becomes unnecessary, the current command value iq * 'is set to 0 and the relay closing process is executed because the current command value iq *' used for the capacitor voltage control is used. When the auxiliary relay 3 is turned on and normal motor control is started, the motor torque suddenly changes or the resistance
This is because burnout 4 may occur. That is, in the preceding motor control, it can be said that it is important to control the torque component current iq to 0 (zero) after the capacitor terminal voltage reaches a predetermined voltage.

Incidentally, the burnout of the resistor 4 occurs when there is an error between the value of the voltage command used in the capacitor voltage controller 19 and the actual voltage VB of the battery 1 while performing the capacitor voltage control. When the relay 3 is turned on, the terminal voltage of the capacitor 5 becomes equal to the actual battery voltage and differs from the voltage command, so that the torque current command iq * 'changes. When the torque current command iq * 'is positive, a current flows from the battery 1 to the motor 7 through the resistor 4, and the resistor 4 is burned. Similarly, when the torque current command iq * 'is negative, a regenerative current flows from the motor 7 to the battery 1 through the resistor 4, and the resistor 4 is burned.

[0035] In the above-described first embodiment, first, when it is determined that Vc ≦ VB ₀ or VB in the capacitor voltage determining unit 16,
Although an example in which the power-on control is executed by the relay input unit 17 has been described, since the required control time is extremely short as described later, the capacitor voltage control unit 19 executes the preceding motor control from the beginning, and Vc ≦ VB ₀ or VB during control
May be determined, and the process may shift to power-on control.

Next, the relay input unit 17 turns on Ry2 and turns on the auxiliary relay 3 by the above-mentioned flag ryon.
At this time, if there is a voltage difference between the voltage Vc across the capacitor 5 and the actual battery voltage VB, a current flows through the resistor 4. To reduce the flowing current, the battery voltage
Auxiliary relay by reducing the voltage difference between VB and capacitor voltage Vc
3 needs to be turned on.

For example, the voltage difference that allows a rated current of 1.4 A to flow with a resistance of 20 (Ω) and 40 (W) is within 28 V, but can be suppressed within this range by controlling the capacitor voltage. Also, depending on the heat radiation state of resistor 4,
If it is for 0 ms (about the time constant determined by the capacitor 5 and the resistor 4), it is possible to pass a current of about 10 times the rated value, and the resistance 4 from the battery 1 to the motor 7 or from the motor 7 to the battery 1 If no current flows through the resistor 4, even if the voltage difference between the voltage Vc across the capacitor 5 and the actual battery voltage is larger than the rating, it is considered that the resistor 4 will not burn out.

On the other hand, as another advantage of lowering the voltage of the capacitor 5 by performing the capacitor voltage control, there is a case where an extremely high voltage cannot be applied depending on the type of the battery, and deterioration of such a battery is prevented. Sometimes. In this case, the voltage Vc of the capacitor 5 is the same as the actual battery 1 voltage VB or the actual battery 1 voltage.
Better than VB. Therefore, the control of the determination or the capacitor voltage control unit 19 of the capacitor voltage determination unit 16, it may be desirable to use a minimum guaranteed voltage VB ₀ of the battery 1. Finally, the relay input section 17
After a certain time from the input of 3, the signal Ry1 is turned on and the relay 2 is turned on, and then the signal Ry2 is turned off and the auxiliary relay is turned off.
Execute "power-on control" to turn off 3.

When a series of the above-described processes for turning on the relay is completed, the relay turning-on section 17 sets a flag trqon,
With rqon, the torque shock absorption processing unit 20 gradually returns the torque command value TRQ 'from 0 to the original command value. i
The d * command value calculation unit 15 calculates the current command value id * according to the torque command value TRQ ', and the iq * command value calculation unit 16 calculates the torque command value T
Calculate the current command value iq * according to RQ '. Current control processing unit 2
1 controls the motor current according to the current command value id * and the current command value iq *. After turning on relay 2, torque command value T
Since RQ 'is gradually increased from 0, the current command value of the torque component does not become discontinuous with the value calculated by the capacitor voltage control unit 19, so that a sudden change in the motor torque does not occur. It is good that the behavior change of the electric vehicle is small.

With the above processing, the normal "motor control"
Can be returned to. The method shown in FIG. 1 focuses on the voltage of the capacitor and makes it possible to turn on the relay regardless of the motor rotation speed. This is particularly effective when a high voltage is applied to the battery to deteriorate the battery.

Among the processes performed by the controller 9, the id * command value calculation unit 14, the iq * command value calculation unit 15, the relay input unit 17, the capacitor voltage processing unit 19, and the torque shock absorption processing unit 20
Is performed at a relatively long interval of 2 ms or more, whereas the current control processing unit 21
It is performed at a short interval of about 00 μs. For the PWM output stop unit 22, if the microcomputer itself has a function of stopping the PWM signal, that function is used. As another method, a method of externally creating a circuit that performs an AND operation with a PWM signal and outputting a signal to the circuit can be considered.

Next, a capacitor voltage determining section 16, a relay input section 17, a current command switching section 18, a capacitor voltage control section 19,
For details of the torque shock absorption processing unit 20 and the like,
This will be described with reference to a flowchart. FIG. 2 is a diagram illustrating a flowchart (initialization) of the capacitor voltage determination according to the first embodiment. FIG. 2 shows a capacitor voltage determination process performed as part of the initialization process of the controller 9 when the key switch is turned on. here,
It is assumed that the key switch is turned off and then the key switch is turned on again, and that the signal Ry1 is turned off and the inverter relay is disconnected.

First, the PWM output is stopped so that the PWM signal is not output (step 25). Voltage V across capacitor 5
It is determined whether or not c is equal to or less than a predetermined minimum guaranteed voltage value of battery 1 or voltage VB of battery 1 (step 26). When the voltage Vc at both ends of the capacitor 5 is smaller, the flag Vccont is set to 0 to perform the relay closing process.
(Step 27), and the flag ryo for permitting the relay
n is set to 1 (step 28). Voltage Vc across capacitor 5
If is larger, it is necessary to perform a relay re-closing process employing capacitor voltage control, and the flag Vccont is set to 1 (step 29). Then, the flags flagINVRY and flagVc used in the relay closing process are cleared to 0, and the torque command value TRQ 'is set to 0. (Steps 30, 31, 32).

FIG. 3 is a diagram showing a flowchart (at the time of failure) of the capacitor voltage judgment of the first embodiment. In FIG. 3, although the key switch is turned on, the controller 9 makes a determination such as a failure (fail), disconnects the relay 2, stops the motor control, and then (when the failure is recovered) 3 shows a capacitor voltage determination process performed as a part of the process of the controller 9 when returning to the motor control. This process is a process that is executed at every fixed sampling time.

First, it is determined whether the rotation speed ω of the motor 7 exceeds the maximum speed ωMAX of the motor (step 35). If it exceeds, the flag flagFAIL is set to 1 (step 36),
The signal Ry1 is turned off to disconnect the relay 2 (step 37).
The output of the PWM signal from the controller 9 is stopped (step 38). The rotational speed ω of the motor 7 is the maximum motor speed ωMAX
If not, it is determined whether the flag flagFAIL is 1 (step 39). If the flag flagFAIL is 1, the flag flagFAIL is set to 0 (step 40).

Then, it is determined whether or not the voltage Vc across the capacitor 5 is equal to or lower than a predetermined minimum guarantee voltage of the battery 1 or the voltage VB of the battery 1 (step S1).
41). When the voltage Vc at both ends of the capacitor 5 is smaller, the flag Vccont is set to 0 to perform the relay closing process.
(Step 42) The flag ryon is set to 1 (Step 43). When the voltage Vc at both ends of the capacitor 5 is large, it is necessary to perform a relay re-input process employing capacitor voltage control, and the flag Vccont is set to 1 (step 44). then,
Set the flags flagINVRY and flagVc used in the relay input process to 0
Clear and set the torque command value TRQ 'to 0 (steps 45 and 4).
6,47). The processing in FIG. 3 is a case where the relay 2 is cut off due to a rotational speed abnormality of the motor 7, but the relay 2 may be cut off due to another abnormality. This is a capacitor voltage determination process when the relay 2 is turned on again after the abnormality is eliminated.

FIG. 4 is a diagram showing a flow chart of the current command value calculation of the first embodiment. 4 is a process of calculating a current command value (id *, iq *).
The processing of the switching unit 18 that switches the current command calculated by the switching unit 18 is also included. Note that the process of FIG. 4 is executed at a constant sampling time after the initialization process of the controller 9 is completed. As described above, the process is executed at a longer sampling interval than the current control processing unit 21.

First, it is determined whether or not the flag flagFAIL is 0 (step 50). If it is 1, it is a failure,
It does not calculate the current command value. Next, it is determined whether or not the flag Vccont is 0 (step 51). Flag Vcco
If nt is 0, the capacitor voltage control has been completed, and the relay can be turned on. When the flag Vccont is 1
If not (0), capacitor voltage control is performed (step 56). Next, it is determined whether or not the flag ryon is 0 (step 52). Here, if the flag ryon is 0, the relay closing process has been completed. When the flag ryon is 1 (not 0), a relay closing process is performed (step 57). Next, it is determined whether or not the flag trqon is 0 (step 53). When the flag trqon is 0, the torque shock absorption processing has been completed. When the flag trqon is 1 (not 0), a torque shock absorption process is performed (step 58).

When the flags Vccont, ryon, and trqon are all 0, it can be considered that normal motor control has been restored. At that time, the current command value id * is obtained by a table search or the like in consideration of high efficiency based on the torque command value TRQ and the motor rotation speed ω (step 54). The current command value iq * is obtained by a table search or the like in consideration of high efficiency based on the torque command value TRQ and the current command value id * (step 55).

As a process attached to normal motor control, it is determined whether or not the torque component current command value iq * is substantially 0 (step 59). Torque component current command value iq
When * is approximately 0, it is determined that the voltage Vc across the capacitor 5 is substantially equal to the voltage VB of the battery 1 and the voltage Vc across the capacitor 5 is determined as the voltage of the battery 1.
Save as VB in the memory of controller 9 (step
60).

FIG. 5 is a flowchart showing the capacitor voltage control of the first embodiment. First, the current command value id
* Is determined by a table search or the like considering high efficiency based on the torque command value TRQ 'and the motor rotation speed ω (step 6
1). At this time, the torque command value TRQ 'is set to 0, and the voltage generated by the permanent magnet type synchronous motor is suppressed by the field weakening control. next,
It is determined whether or not flagVc is 0 (step 62). The flag flagVc is the voltage Vc of the capacitor 5 and the voltage VB of the battery 1.
Are almost the same.

If the flag flagVc is 0, the torque component current command value iq * is changed to the voltage VB of the battery 1 and the voltage V
It is determined from the voltage difference from c (step 63). When the voltage of the battery 1 is high, the torque component current command value iq * is made positive, and the electric charge stored in the capacitor 5 is consumed as torque to lower the voltage of the capacitor 5. When the voltage of the battery 1 is low, the torque component current command value iq * is set to a negative value, the electric charge is stored in the capacitor 5 by the regenerative torque, and the capacitor 5
Increase the voltage. Here, although the torque component current command value iq * is a value (proportional value) according to the voltage difference between the voltage VB of the battery 1 and the voltage Vc of the capacitor 5 as the predetermined voltage, the torque component current command value iq * iq * may be a positive and negative constant value. Battery 1 voltage VB and capacitor 5
When the voltage Vc is substantially equal, the flag flagVc is set to 1.
(Step 64, Step 65). Finally, the current control processing unit 21
The stop of the PWM signal calculated by is released, and the output of the PWM signal to the inverter 6 is permitted. (Step 71).

On the other hand, when the flag flagVc is 1, the torque component current command value iq * is set to 0 (step 66), so that no torque is output. If the torque component current detection value iq becomes 0 (step 67), the flag Vccont is set to 0 (step 6).
8) The flag ryon is set to 1 (step 69), and the auxiliary relay 3 is permitted to be turned on. Clear the value of variable time2
(Step 70). In step 67, it is determined whether the torque component current detection value iq is 0. However, a method of adjusting only the current response time may be used.

FIG. 6 is a flowchart showing a relay closing process according to the first embodiment. First, the flag flagINVRY
Is checked (step 75). The flag flagINVRY indicates that the inverter relay is turned on. Flag flagINVRY
Is 0, the port output signal Ry2 is turned on to turn on the auxiliary relay (step 76). After turning on the auxiliary relay 3, the time required until the voltage VB of the battery 1 matches the voltage Vc of the capacitor 5 is adjusted (step 77). When the value of the variable time2 exceeds the fixed value α2 (step 78), the flag flagINVRY is set to 1 (step 79), and the turning on of the inverter relay is permitted. Clear the value of variable time1. (Step 80).

When the flag flagINVRY is 1, the signal Ry1 output from the port is turned on to turn on the inverter relay (step 81). Actually, a time delay until the inverter relay is turned on is adjusted (step 82). When the value of the variable time1 exceeds a certain value α1 (step 83), the flag trqon is set to 1 (step 84), the flag ryon is set to 0 (step 85), and the torque command value TRQ is returned to the normal value. To give permission. Further, the signal Ry2 output to the port is turned off, and the auxiliary relay is turned off (step 86). The output of the PWM signal is permitted (step 87).

FIG. 7 is a flowchart showing a torque shock absorbing process according to the first embodiment. By performing this process, in addition to the component damage that occurs when the driver accidentally turns off the key switch during high-speed driving and notices that the key switch is turned on again, the current command calculated by the capacitor voltage control unit 19 and the accelerator It is also possible to prevent a change in the behavior of the electric vehicle due to a sudden change in torque, which occurs when there is a large difference between the current commands calculated by the current command value calculation processing units 14 and 15 due to the torque command determined by the brake and the brake.

First, an externally input torque command value T
It is determined whether RQ is positive or negative (step 90). When the value is positive, the value of the torque command value TRQ ', which has been 0, is increased little by little (ΔTQ) (step 91), and when the value is negative, the value of the torque command value TRQ' is gradually reduced (ΔTQ) (step 91). 92). Current command value
id * is obtained based on the torque command value TRQ 'and the motor rotation speed ω (step 93). The current command value iq * is converted to the torque command value TRQ '
And the current command value id * (step 94). When the torque command values TRQ and TRQ 'are equal (step 9
5) Then, the flag trqon is set to 0 (step 96), and the torque shock absorption processing ends. As described in steps 52 to 53 in FIG. 4, the torque shock absorption processing is performed after the power-on control of the relay circuit is completed, that is, after the main relay 2 is turned on, the torque of the motor 7 is reduced to 0. From 0 or gradually from 0.

FIG. 8 is a block diagram showing the current control processing unit of the first embodiment. The current control processing unit 21 performs the coordinate conversion 10
0, PI control 101, PI control 102, non-interference control 103, dead time compensation 104, coordinate conversion 105, and triangular wave comparison 106. The coordinate conversion 100 converts the motor currents iu, iv, iw into an excitation component current id and a torque component current iq using the magnetic pole position θ of the motor. The PI control (101) calculation is performed by comparing the excitation current command value id * with the excitation current id. Torque current command value
PI control (102) by comparing iq * with torque current iq
Perform calculations. The non-interference control 103 is performed with the excitation current command value id *
Then, voltage command values Vdc and Vqc for removing interference between the d-axis and the q-axis are calculated from the current command value iq * and the torque component current command value iq *. PI control (101,102)
And the voltage command values Vdc and Vqc calculated by the non-interference control (103) are added to obtain voltage command values Vd and Vq.

The coordinate conversion 105 uses the magnetic pole position θ of the motor to convert the voltage command values Vdc and Vqc into AC three-phase voltage command values Vu, Vv and Vw.
Convert to The dead time compensation 104 calculates dead time compensation voltage values Vud, Vvd, Vwd using the magnetic pole position θ of the motor. Dead time compensation voltage values Vud, Vvd, Vwd are added to the AC three-phase voltage command values Vu, Vv, Vw to obtain final AC three-phase voltage command values Vu, Vv, Vw. The triangular wave comparison unit 106
(Triangular wave) and the three-phase AC voltage command values Vu, Vv, Vw
Create a PWM signal. Note that the triangular wave comparison unit 106 is configured not using software processing but using an internal counter and the like, and is capable of automatically generating six PWM signals required to drive the inverter 6. You may.

Although the description has been given of the case where the relay circuit is turned on again while performing the current control,
Similarly, when the inverter relay is disconnected at the time of the failure in FIG. 3, a method of disconnecting the relay while performing current control is also conceivable. Thereby, the shock of torque when the relay is disconnected can also be reduced.

Next, another embodiment will be described as a second embodiment. FIG. 9 is a diagram showing an electric vehicle control device according to a second embodiment of the present invention. In the figure, the electric vehicle control device includes a relay 11 as an inverter relay.
2, auxiliary relay 113, current limiting resistor 114, capacitor 1
15, an inverter 116, and a controller 119. The electric vehicle includes a key switch 23, a battery 111, a motor 117 as a permanent magnet type synchronous motor, a current sensor 118, an encoder 120, a magnetic pole position sensor 121, a differential gear 122, and driving wheels 123.

During normal running, battery 111 and inverter 116 are connected via relay 112 and capacitor 115. Inverter 116 is PWM output from controller 119
Controlled by a signal, a voltage is applied to the motor 117. The current flowing through the motor 117 is detected by the current sensor 118 and taken into the controller 119. The rotation speed of the motor 117 is detected by the encoder 120, and the magnetic pole position of the motor 117 is detected by the magnetic pole position sensor 121, and are taken into the controller 119. The torque of the motor 117 is transmitted to the drive wheels 123 through the differential gear 122.

The controller 119 includes an id * command value calculator 12
4, iq * command value calculation unit 125, speed determination unit 126, relay input unit 127, current command switching unit 128, capacitor voltage control unit 12
9, torque shock absorption processing unit 130, current control processing unit 13
1, comprising a PWM output stop unit 132. When the key switch 23 of the electric vehicle is turned on, control power is applied to the controller 119, and control in the controller 119 is activated. Similarly, turning off the key switch 23 stops power supply to the controller 119 and stops the control operation in the controller 119.

The processing from turning on the key switch 23 of the electric vehicle to running is the same as that described with reference to FIG. 1, and the motor control operates in the same manner as that shown in FIG. When the electric vehicle having the configuration shown in FIG. 9 is traveling at high speed on a downhill, the driver turns off the key switch 23, and the driver turns off the key switch 23 in a state where the relay 112 is disconnected and the motor control is stopped. Consider a case where the vehicle is turned on again to return to normal running. In FIG. 9, when the rotation speed of the motor 117 is high, a high induced voltage is generated at the terminal of the motor 117. At this time, if the key switch 23 is turned off, the controller 119 stops and the PWM signals Pu, Pv, Pw are turned off. The voltage Vc of the capacitor 115 is high due to the diode rectification of the inverter 116 (corresponding to the line voltage of the motor).
Is charged.

In this state, when the key switch 23 is turned on and the controller 119 is started, first, the speed judging section 126 judges whether or not the rotation speed ω of the motor 117 is larger than a predetermined value. When the rotation speed ω of the motor 117 is high, the voltage generated at the input side of the inverter may be higher than the voltage VB of the battery 111. At this time, if the auxiliary relay 113 is turned on as it is, there is a possibility that the auxiliary relay 113 and the resistor 114 may be broken due to an overcurrent. Therefore, before turning on the auxiliary relay 113, the “capacitor voltage control” as the preceding motor control is executed. And the capacitor 115
To lower the voltage across the terminals.

That is, when the rotation speed ω of the motor 117 is high, the flag Vccont is set, and the capacitor voltage control unit 129 sets the voltage Vc of the capacitor 115 to the voltage Vc of the battery 111.
Execute control to match B. This matching voltage VB is
The voltage VB of the actual battery 111 measured using the previously minimum guaranteed voltage VB ₀ or battery voltage sensor is determined. Note that the voltage VB of the battery 111 is obtained from communication information from a microcomputer that manages the charging of the battery or at the time when the electric vehicle is running (in particular, when the relay 112 is turned on and the torque command is 0). From the measured voltage across the capacitor 115 (at the time), stored in the memory of the controller 119 as the voltage of the battery 111,
You may get it.

When the rotation speed ω of the motor 117 is low, the flag ryon is set, and the relay closing process 127 is performed.
This is because even when a high voltage remains in the capacitor 115, when the rotation speed ω is low (when the line voltage of the motor is considered to be sufficiently lower than the voltage of the battery), the auxiliary relay 113 is turned on as it is. However, the motor current does not flow to the capacitor 115 side through the diode of the inverter 116, and the energy regenerated in the battery 111 is only the energy of the capacitor 115, and the possibility that the resistor 114 is broken is small. Although it depends on the heat radiation state of the resistor 114, the time required for the battery 111 to be charged from the capacitor 115 is considered to be about several tens of milliseconds, and it is considered that an overcurrent of about 10 times the rating can withstand sufficiently.

In the case of the present embodiment shown in FIG. 9, the case where the key switch 23 of the electric vehicle is turned off for a long time and the key switch 23 is turned on after the electric vehicle finishes descending the hill and the speed is considerably reduced is considered. The determination as to whether or not to perform the processing for preventing burnout of the resistor 114 is made based on the rotation speed of the motor.

In the relay input process 127, first, Ry2 is turned on to turn on the auxiliary relay 113, and the capacitor 115 and the battery
After a certain period of time when the voltage of 111 becomes equal, Ry1 is turned on and the relay 112 is turned on.Ry2 is turned off and the auxiliary relay 11 is turned on.
3 is to cut. At this time, a method of actually measuring the voltage of the capacitor 115 and confirming that the voltage becomes equal to the voltage of the battery 111 and then turning on Ry1 to turn on the relay 112 is also conceivable.

When the flag Vccont is set, the capacitor voltage control unit 129 calculates the current command value iq * 'so that the voltage Vc of the capacitor 115 becomes equal to the voltage VB of the battery 111. The switching unit 128 replaces the current command value iq * with the current command value iq * calculated by the iq *
Select '*'. The torque shock absorption processing unit 130 sets the torque command value TRQ 'to 0. The id * command value calculation unit 124 calculates a current command value id * when the torque command value TRQ 'is set to 0 in the field-weakening region in the high rotation range according to the motor rotation speed ω. The PWM output stop unit 132 permits the output of the PWM signals Pu, Pv, Pw, and the current control processing unit 131 performs current control according to the current command values iq * ', id *. At this time, by performing the field weakening control, the induced voltage generated by the permanent magnet motor can be suppressed, and the line voltage can be made equal to or less than the maximum voltage that can be output by the inverter (イ ン バ ー タ battery voltage). Further, a positive torque current flows, and the electric charge charged in the capacitor 115 is consumed as torque, so that the voltage of the capacitor 115 is reduced.

The voltage Vc of the capacitor 115 is equal to the battery voltage VB
In a state almost equal to
Sets the current command value iq * 'to 0. Current control processing unit 131
Performs current control according to the current command values iq * ', id *. When the torque current value iq becomes equal to the command value iq * '(= 0) or when a predetermined current response time has elapsed, the capacitor voltage control unit 129 sets the flag r
By setting yon, the relay input process 127 turns on Ry2 and turns on the auxiliary relay 113. The relay input process 127 turns on the signal Ry1 to turn on the relay 112 and then turns off the signal Ry2 and turns off the auxiliary relay, after a lapse of a predetermined time from the turning on of the auxiliary relay 113.

The torque shock absorption processing section 130 gradually returns the torque command value TRQ 'from 0 to the original command value. The id * command value calculation unit 124 calculates the current command value id * according to the torque command value TRQ ', and the iq * command value calculation unit 125 calculates the current command value iq * according to the torque command value TRQ'. The current control processing unit 131 controls the motor current according to the current command value id * and the current command value iq *. After turning on the inverter relay 2, the torque command value TRQ 'is gradually increased from 0.
Since there is no discontinuity with the value calculated in 129, there is no sudden change in motor torque. It is good that the behavior change of the electric vehicle is small. With the above processing, it is possible to return to the normal motor control.

The electric vehicle control apparatus according to the present embodiment shown in FIG. 9 performs a preceding control (in other words, a consumption control) for preventing the relay circuit from burning and overcharging the battery and turns on the relay. Whether the relay is turned on as usual without performing the preceding control can be selected according to the motor rotation speed.

In the processing performed by the controller 119, the id * command value calculation unit 124, the iq * command value calculation unit 125, the relay input unit 127, the capacitor voltage processing unit 129, and the torque shock absorption processing unit 130 Perform at relatively long intervals of 2 ms or more. In contrast, the current control processing unit 131
The sampling is performed at a short interval of about 100 μs.

FIG. 10 is a diagram showing a flowchart (initialization) of the speed judgment in the second embodiment. 10 is a flowchart of a capacitor voltage determination process performed as part of the initialization process of the controller 119 when the key switch 23 is turned on. Here, it is assumed that the key switch 23 is turned off and then the key switch 23 is turned on, that is, the signal Ry1 is turned off and the inverter relay is disconnected.

First, the PWM output is stopped so that the PWM signal is not output (step 135). Preset rotation speed ωry where the rotation speed ω of the permanent magnet type synchronous motor is predetermined
It is determined whether it is smaller than (Step 136).
Note that this preset value rotation speed ωr
If y is set so that the voltage generated on the input side of the inverter by the rotation of the permanent magnet type synchronous motor is equal to or lower than the minimum guaranteed voltage of the battery, the motor 117 can be turned on even if the auxiliary relay is turned on. Battery through resistor 114
No current flows into 111.

The rotation speed ω of the permanent magnet type synchronous motor is ωry
If it is smaller, the flag Vccont is set to 0 (step 137) and the flag ryon is set to 1 in order to perform the relay input processing.
(Step 138). If the rotation speed ω of the permanent magnet type synchronous motor is higher than ωry, the voltage of the capacitor 115 may be higher than the voltage of the battery 111. Therefore, the flag Vccont is set to 1 to perform the capacitor voltage control. (Step 139). Then, the flags flagINVRY and flagVc used in the relay closing process are cleared to 0, and the torque command value TRQ 'is set to 0. (Steps 140, 141, 142).

FIG. 11 is a view showing a flow chart (at the time of failure) of the speed judgment of the second embodiment. Key switch 2
3 is turned on, but controller 119
Is a flowchart of a capacitor voltage determination process performed as part of the process of the controller 119 when the motor control is stopped by determining the failure (failure), disconnecting the relay 112, and then returning to the normal motor control. It is. This process is a process that is executed at every fixed sampling time.

First, it is determined whether the rotation speed ω of the motor 117 exceeds the maximum speed ωMAX of the motor (step 145).
If it exceeds, the flag flagFAIL is set to 1 (step 14).
6) The signal Ry1 is turned off to disconnect the relay 112 (step 147). The output of the PWM signal from the controller 119 is stopped (step 148). If the rotation speed ω of the motor 117 does not exceed the maximum speed ωMAX of the motor, the flag flagFAIL
Is determined to be 1 (step 149). Flag fla
If gFAIL is 1, the flag flagFAIL is set to 0 (step 150).

Then, it is determined whether or not the rotation speed ω of the motor 117 is smaller than a predetermined ωry.
(Step 151). If the rotation speed ω of the permanent magnet type synchronous motor is smaller than ωry,
The flag Vccont is set to 0 (step 152), and the flag ryon is set to 1 (step 153). If the rotation speed ω of the permanent magnet type synchronous motor is higher than ωry, it is necessary to perform capacitor voltage control processing, and the flag Vccont is set to 1 (step 154). Then, the flag fl used in the relay input processing
agINVRY, flagVc is cleared to 0, and the torque command value TRQ 'is set to 0 (steps 155, 156, 157).

Although the process here is a case where the relay 112 is cut off due to an abnormal rotation speed of the motor 117, the relay 112 may be cut off due to other abnormalities. This is a capacitor voltage determination process when the relay 112 is turned on again after the abnormality is eliminated. Also, id *,
Regarding the iq * command value calculation processing, the capacitor voltage control processing, the relay closing processing, and the torque shock absorption processing, those similar to the flowcharts shown in FIGS. 4, 5, 6, and 7 can be used, respectively. Further, as the current control processing unit 131, the same one as the block diagram shown in FIG. 8 can be used.

Next, another embodiment will be described as a third embodiment. FIG. 12 is a diagram showing an electric vehicle control device according to a third embodiment of the present invention. The electric vehicle control device shown in the figure includes a relay 162 as an inverter relay, an auxiliary relay 163, a current limiting resistor 164, a capacitor 165,
It comprises an inverter 166, a controller 169, and a current sensor 182 for inverter input. The electric vehicle includes a key switch 23, a battery 161, a motor 167 as a permanent magnet type synchronous motor, a current sensor 168 for the motor, and an encoder 17
0, magnetic pole position sensor 171, differential gear 172,
The driving wheel 173 is included.

During normal running, battery 161 and inverter 166 are connected via relay 162 and capacitor 165. Inverter 166 is PWM output from controller 169
Controlled by a signal, a voltage is applied to the motor 167. The current flowing through the motor 167 is detected by the current sensor 168 and is taken into the controller 169. The rotation speed of the motor 167 is detected by the encoder 170, and the magnetic pole position of the motor 167 is detected by the magnetic pole position sensor 171, and the magnetic pole position is taken into the controller 169. The torque of the motor 167 is transmitted to the drive wheels 173 through the differential gear 172.

The controller 169 has an id * command value calculation unit 17
4, iq * command value calculation section 175, relay input section 176, current command switching 177, inverter input current control section 178, torque shock absorption processing section 179, current control processing section 180, PWM output stop section 181
Consists of When the key switch 23 of the electric vehicle is turned on, the control power is applied to the controller 169, and the control in the controller 169 is activated.
Similarly, turning off the key switch stops power supply to the controller 169, and stops the control operation in the controller 169.

The processing from turning on the key switch 23 of the electric vehicle to running is the same as that described with reference to FIG. 1, and the motor control operates in the same manner as that shown in FIG. When the electric vehicle having the configuration shown in FIG. 12 is traveling at high speed on a downhill, the driver turns off the key switch 23, and the driver turns off the key switch 23 from a state where the relay 162 is disconnected and the motor control is stopped. It is assumed that the vehicle is turned on to return to normal running. The electric vehicle control device having the configuration shown in FIG. 12, when there is no means for directly measuring the capacitor voltage,
The current sensor used for measuring the battery current is also used as the current sensor 182 for inputting to the inverter, so as to return to normal running. In FIG. 12, the motor
When the rotation speed of the 167 is high, a high induced voltage is generated at the terminal of the motor 167. At this time, if the key switch 23 is turned off, the controller 169 stops and the PWM signals Pu, Pv, Pw are turned off. By the diode rectification of the inverter 166, the voltage Vc of the capacitor 165 is charged to a high voltage (corresponding to the line voltage of the motor).

In this state, when the key switch 23 is turned on and the auxiliary relay 163 is turned on, the regenerative current as the induced power from the permanent magnet type synchronous motor is supplied to the auxiliary relay 163 and the resistor 1.
The controller 169 uses the current signal from the inverter input current sensor 182 to perform “inverter input current control” as a preceding motor control such that the inverter input current iINV becomes 0, since the inverter input current control 182 may be destroyed. While performing, turn on the relay circuit (auxiliary relay 163).

That is, when the inverter input current iINV can be made zero, the current flowing from the motor 167 to the capacitor 165 through the inverter 166 is zero.
In this state, even if the auxiliary relay 163 is turned on, the capacitor 1
Only the charge charged in the battery 65 is charged in the battery 161, and the regenerative current induced by the motor 167 does not flow into the battery 161, so that there is little possibility that the resistor 164 or the like is broken.

At this time, the current flowing to the relay circuit side depends on the potential difference between the capacitor 165 and the battery 161 and the resistance 164.
Is determined from the size of Assume that the internal resistance of the battery 161 is sufficiently smaller than the resistance 164 (in other words, the resistance
When the resistance value of 164 is larger than the internal resistance of battery 161), the current flowing through the relay circuit converges to 0 in several tens ms as a time constant calculated from capacitor 165 and resistor 164. Therefore, it is considered that the influence on the auxiliary relay 163, the resistor 164, the battery 161 and the like is small.

Then, the inverter input current control unit 178
Is the inverter input current iINV detected by the current sensor 182.
The current command value iq * 'is calculated so that is equal to zero. The switching unit 177 includes a current command value iq * calculated by the iq * command value calculation unit 175.
Instead, the current command value iq * 'is selected. The torque shock absorption processing unit 179 sets the torque command value TRQ 'to 0. i
The d * command value calculation unit 174 calculates a current command value id * when the torque command value TRQ 'is set to 0 in the field-weakening region in the high rotation range according to the motor rotation speed ω. The PWM output stop unit 181
The output of the WM signals Pu, Pv, Pw is permitted, and the current control processing unit 180
Performs current control according to the current command values iq * ', id *.

When the torque component current value iq becomes equal to the command value iq * ', or when a predetermined time of a predetermined current response has elapsed, the inverter input current control unit 178
Sets the flag ryon, and the relay input process 127 turns on Ry2 and turns on the auxiliary relay 163. Relay input processing 176
Is a predetermined time after the auxiliary relay 163 is turned on.
y1 is turned on to turn on relay 162, and then signal Ry2 is turned off to turn off the auxiliary relay.

The torque shock absorption processing section 179 gradually returns the torque command value TRQ 'from 0 to the original command value. The id * command value calculation unit 174 calculates the current command value id * according to the torque command value TRQ ′, and the iq * command value calculation unit 175 calculates the current command value iq * according to the torque command value TRQ ′. The current control processing unit 180 controls the motor current according to the current command value id * and the current command value iq *. After turning on relay 162,
In order to gradually increase the torque command value TRQ 'from 0, the current command value of the torque
Since the value does not become discontinuous with the value calculated in (1), no abrupt change in motor torque occurs. With the above processing, it is possible to return to the normal motor control.

The electric vehicle control apparatus of this embodiment shown in FIG. 12 does not include a means for measuring a voltage, but also serves as a current sensor used for measuring a battery current.
Preliminary control that sets the current input to the inverter to zero to prevent the relay circuit from burning and overcharging the battery
By performing (in other words, consumption control), the rotational energy of the motor is not regenerated to the battery side. If the system uses a current sensor in advance for battery energy management and the like, there is no need for a battery or capacitor voltage sensor, and there is a feature that it can be cheaper than the first and second embodiments.

In the processing performed by the controller 169, the id * command value calculation section 174, iq * command value calculation section 175, relay input section 176, inverter input current control section 178, and torque shock absorption processing section 179 perform sampling. While the current control processing unit 180 performs at a relatively long interval of 2 ms or more,
The sampling is performed at a short interval of about 100 μs.

FIG. 13 is a diagram showing a flow chart of the current command value calculation of the third embodiment. This is a current command value (id *, iq *) calculation process, in which switching to a current command by the inverter input current control unit 178 is performed. This process is performed by the controller
After the initialization processing of step 169 is completed, the processing is executed at a constant sampling time. Also, it is executed at a longer sampling interval than the current control processing unit 180. To perform this processing, the flag flagINVCONT is set to 1 and the flag ryon is set to 0 in the initialization processing. Flags used in relay input processing
Clear INVRY, variable time3 and torque command value TRQ 'to zero.

First, it is determined whether or not the flag flagINVCONT is 0 (step 185). The flag flagINVCONT is 0
If so, the relay input process has been completed. Flag flagIN
When VCONT is not 0 (when it is 1), the relay input process is performed while performing the inverter input current control (step 190) (steps 191 and 192). Next, it is determined whether or not the flag trqon is 0 (step 186). When the flag trqon is 0, the torque shock absorption processing has been completed. When the flag trqon is not 0
In the case of (1), it is necessary to perform a torque shock absorption process (step 189).

When the flag flagINVCONT, trqon is 0,
It can be considered that normal motor control has been restored. At this time, the current command value id * is obtained by a table search or the like in consideration of high efficiency based on the torque command value TRQ and the motor rotation speed ω (step 187). Further, a current command value iq * is obtained by a table search or the like in consideration of high efficiency based on the torque command value TRQ and the current command value id * (step 188).

FIG. 14 is a flowchart showing the inverter input current control processing of the third embodiment. 4 shows a flowchart of inverter input current control. First, the current command value id * is obtained by searching a table or the like in consideration of high efficiency based on the torque command value TRQ 'and the motor rotation speed ω.
(Step 195). At this time, the torque command value TRQ 'is set to 0, and the generated voltage of the permanent magnet type synchronous motor is further suppressed by the field weakening control. The torque component current command value iq * is obtained from the inverter input current iINV (step 196). When the inverter input current iINV is negative (regeneration), the torque component current command value iq * is made positive. Conversely, when the input current iINV is positive (power running), the torque component current command value iq * is made negative. Here, the magnitude of the torque component current command value iq * is determined by the input current iIN
Although proportional to the magnitude of V, the proportional / integral control may be performed.

Next, the output of the PWM signal is permitted (step
197). Next, after adjusting the time of the current response (steps 198 and 199), the flag ryon is set to 1 (step 200), and a relay closing process is performed (step 201).
Regarding the relay input processing, step 85 of the flowchart shown in FIG.
VCONT = 0 can be used as it is. The torque shock absorption process can use the flowchart shown in FIG. 7 as it is. In addition, current control processing 131
Also, the block diagram shown in FIG. 8 can be used.

Next, another embodiment will be described as a fourth embodiment. FIG. 15 is a diagram showing an electric vehicle control device according to a fourth embodiment of the present invention. In the figure, the electric vehicle control device includes a relay 212 as an inverter relay, an auxiliary relay 213, a current limiting resistor 214, a capacitor 215, an inverter 216, and a controller 219. Electric vehicle has key switch 23, battery 21
1. It includes a motor 217 as a permanent magnet type synchronous motor, a current sensor 218, an encoder 220, a magnetic pole position sensor 221, a differential gear 222, and driving wheels 223.

During normal running, the battery 221 and the inverter 216
Are connected via a relay 212. The inverter 216 is controlled by a PWM signal output from the controller 219, and applies a voltage to the motor 217. The current flowing through the motor 217 is detected by the current sensor 218 and is taken into the controller 219. The rotation speed of the motor 217 is detected by the encoder 220, and the magnetic pole position of the motor 217 is detected by the magnetic pole position sensor 221, and are taken into the controller 219. The torque of the motor 217 is the differential gear 222
Through the drive wheel 223.

The controller 219 includes an id * command value calculation unit 22
4, iq * command value calculation unit 225, relay input unit 226, switching unit 22
7, an iq0 control unit 228, a torque shock absorption processing unit 229, a current control processing unit 230, and a PWM output stop unit 231. Although not shown, a control power supply is applied to the controller 219 by turning on a key switch of the electric vehicle, and the control in the controller 219 is activated. Similarly, by turning off the key switch, the controller 2
The power is not applied to 19, and the control in the controller 219 stops.

The process from turning on the key switch of the electric vehicle to running is the same as that described with reference to FIG. 1, and the motor control operates in the same manner as that shown in FIG. When the electric vehicle having the configuration shown in FIG. 15 is traveling at high speed on a downhill, the driver turns off the key switch, the relay 212 is disconnected, and the motor control is stopped. Is turned on to return to normal running. The electric vehicle control device having the configuration shown in FIG. 15 shows an embodiment in which the vehicle returns to normal running without using the capacitor voltage sensor (first and second embodiments) and the inverter input current sensor (third embodiment). ing.

In FIG. 15, when the rotation speed of the motor 217 is high, a high induced voltage is generated at the terminal of the motor 217.
When the key switch 23 is turned off, the controller 219 stops, and the PWM signals Pu, Pv, and Pw are turned off.
By the diode rectification of step 6, the voltage Vc of the capacitor 215 is charged to a high voltage (a voltage equal to the line voltage of the motor). In this state, when the key switch is turned on again and the auxiliary relay 213 is turned on, the auxiliary relay 213 and the resistor 214 may be broken due to a regenerative current from the permanent magnet type synchronous motor, and an overcharge current may flow to the battery 211. Therefore, the controller 219 calculates the motor torque current value
“iq” as the preceding motor control to set iq to 0 (zero)
Turn on the relay circuit (auxiliary relay 213) while performing “0 control”. If the torque current value iq can be controlled to 0, even if the auxiliary relay 213 is turned on, only the charge in the capacitor 215 will be charged to the battery 211. Therefore, the regenerative current induced by the motor 217 does not flow into the battery 211. That is, if the relay is turned on while controlling the torque current to 0, the relay can be turned on without regenerating the motor current to the battery.

The current flowing to the relay circuit side at this time is determined by the potential difference between the capacitor 215 and the battery 211 and the magnitude of the resistor 214. The resistance of the resistor 214
If the internal resistance is sufficiently larger than 1, the current flowing through the relay circuit converges to 0 in several tens of ms as a time constant calculated from the capacitor 215 and the resistor 214. Therefore, it is considered that the influence of the induced power of the auxiliary relay 213, the resistor 214, and the battery 211 is reduced.

The iq0 control unit 228 sets the current command value to iq
* '= 0. The switching unit 227 selects the current command value iq * 'instead of the current command value iq * calculated by the iq * command value calculation unit 225. The torque shock absorption processing unit 229 calculates the torque command value T
RQ 'is set to 0. The id * command value calculation unit 224 calculates the torque command value in the weak field region in the high rotation region according to the motor rotation speed ω.
The current command value id * when TRQ 'is set to 0 is calculated. PWM
The output stop unit 231 permits the output of the PWM signals Pu, Pv, Pw, and the current control processing unit 230 performs current control according to the current command values iq * ', id *.

When the torque current value iq becomes equal to the command value iq * 'or when a predetermined current response time has elapsed, the iq0 control unit 228 sets the flag ryon.
Then, the relay input process 226 turns on Ry2 and turns on the auxiliary relay 213. A certain time after the auxiliary relay 213 is turned on, the relay input processing 226 turns on the signal Ry1 to turn on the relay 212, and then turns off the signal Ry2 to turn off the auxiliary relay.

The torque shock absorption processing section 229 gradually returns the torque command value TRQ 'from 0 to the original command value. The id * command value calculation unit 224 calculates the current command value id * according to the torque command value TRQ ′, and the iq * command value calculation unit 225 calculates the current command value iq * according to the torque command value TRQ ′. The current control processing unit 230 controls the motor current according to the current command value id * and the current command value iq *. After turning on relay 212,
Since the torque command value TRQ 'is gradually increased from 0, the current command value of the torque component does not become discontinuous with the value calculated by the iq0 control unit 228, so that a sudden change in the motor torque does not occur. With the above processing, it is possible to return to the normal motor control.

The electric vehicle control apparatus of this embodiment shown in FIG. 15 uses only the current sensor 218 without using the capacitor voltage sensor or the inverter input current sensor, and performs the burnout of the relay circuit and the overcharge of the battery. Preventive control to prevent
(In other words, consumption control) to enable the relay to be turned on. There is a feature that the cost can be further reduced as compared with the case of the third embodiment shown in FIG.

Note that among the processing performed by the controller 219, the id * command value calculation section 224, the iq * command value calculation section 225, the relay input section 226, the iq0 control section 228, the torque shock absorption processing section
229 is performed at a relatively long interval of 2 ms or more, and the current control processing unit 230 is performed at a short interval of about 100 μs.

The iq *, id * command value calculation processing 224, 225
The same flowchart as that shown in FIG. 13 may be used. The iq0 control process 228 may be a flowchart in which the step 196 in the inverter input current control process shown in FIG. 14 is changed to iq * = 0. Absorption of torque shock 229
May be the same as the flowchart shown in FIG. The current control process 230 uses the block diagram shown in FIG.

The above is summarized as follows. An inverter that supplies battery power to a permanent magnet synchronous motor that drives the driving wheels of an electric vehicle, a capacitor connected between the upper and lower arms of the inverter, a main relay that connects the battery and the inverter, and a main relay in parallel An auxiliary relay with a current limiting resistor connected in series before the main relay is turned on until the voltage of the connected capacitor and battery becomes equal, and an auxiliary relay and main relay are turned on in response to turning on the key switch. A controller that controls the torque of the permanent magnet synchronous motor by outputting a control signal to the inverter.The driver turns off the key switch while the electric vehicle is running, and the main relay is turned off to turn off the inverter. Operation stops, and the induced voltage generated by the permanent magnet synchronous motor When the auxiliary switch is turned on again by turning on the key switch again, the voltage across the capacitor is higher than the battery voltage. A first current for preventing a current exceeding the capacity of the relay or the capacity of the current limiting resistor from flowing to prevent the auxiliary relay or the current limiting resistor from burning, and further preventing an overcharge current from flowing to the battery. The feature of the electric vehicle control device according to the second embodiment is that a means for checking the voltage of the capacitor and a means for lowering the voltage of the capacitor are provided, and when the key switch is turned on, both ends of the capacitor are turned on before turning on the auxiliary relay. Check the voltage and when the capacitor voltage is higher than the battery voltage, As will properly lower the voltage of the capacitor, the capacitor voltage after becomes equal to the voltage of the battery, it is to put the auxiliary relay.

The electric vehicle control apparatus according to the third and fourth embodiments is characterized in that a means for reducing the current flowing from the permanent magnet type synchronous motor through the inverter to the capacitor to 0 is provided. It can be said that the current flowing from the permanent magnet type synchronous motor to the capacitor through the inverter is set to 0, and the auxiliary relay is turned on.
In other words, when the relay circuit is opened (key switch off and on, that is, the controller is temporarily stopped and restarted) at the time of an erroneous operation or failure (including failure diagnosis) during running, the permanent magnet type synchronous motor Unnecessary charge accumulated in the capacitor caused by the above is transferred to the permanent magnet type synchronous motor by executing the preceding motor control before the closing of the relay circuit (power-on control by turning on the key switch and subsequent motor control) is resumed. The point is that the power is consumed by the motor, and thereafter, the normal power-on control of the battery is executed, and then the normal motor control based on the original charge of the battery is executed.

[0113]

According to the present invention, when a permanent magnet type synchronous motor is used to drive an electric vehicle, the relay connecting the inverter and the battery is disconnected when the permanent magnet type synchronous motor is rotating at high speed. Thus, the control of the inverter is stopped, and the relay can be turned on again even when a high voltage is generated on the input side of the inverter. This is effective in improving the reliability of the electric vehicle control device and the safety of the electric vehicle during high-speed running.

[Brief description of the drawings]

FIG. 1 is a diagram showing an electric vehicle control device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a flowchart (initialization) of capacitor voltage determination according to the first embodiment.

FIG. 3 is a diagram showing a flowchart (at the time of failure) of capacitor voltage determination of the first embodiment.

FIG. 4 is a diagram illustrating a flowchart of a current command value calculation according to the first embodiment.

FIG. 5 is a diagram showing a flowchart of capacitor voltage control of the first embodiment.

FIG. 6 is a diagram showing a flowchart of a relay closing process of the first embodiment.

FIG. 7 is a view showing a flowchart of a torque shock absorbing process of the first embodiment.

FIG. 8 is a diagram illustrating a block diagram of a current control processing unit according to the first embodiment.

FIG. 9 is a diagram showing an electric vehicle control device according to a second embodiment of the present invention.

FIG. 10 is a diagram illustrating a flowchart (initialization) of speed determination according to the second embodiment.

FIG. 11 is a diagram illustrating a flowchart (at the time of failure) of speed determination according to the second embodiment.

FIG. 12 is a diagram showing an electric vehicle control device according to a third embodiment of the present invention.

FIG. 13 is a diagram showing a flowchart of a current command value calculation of the third embodiment.

FIG. 14 is a diagram illustrating a flowchart of an inverter input current control process of the third embodiment.

FIG. 15 is a diagram showing an electric vehicle control device according to a fourth embodiment of the present invention.

[Explanation of symbols]

1,111,161,211… Battery, 2,112,162,212… Inverter relay, 3,113,163,213… Auxiliary relay, 4,114,164,214…
Resistance, 5,115,165,215… Capacitor, 6,116,166,216… Inverter, 7,117,167,217… Motor, 8,118,168,218… Current sensor, 9,119,169,219… Controller, 10,120,170,
220… Encoder, 11,121,171,221… Magnetic pole position sensor, 1
2,122,172,222… differential gear, 13,123,173,
223: drive wheels, 14, 124, 174, 224 ... id * command value calculator, 15, 1
25,175,225 ... iq * command value calculation unit, 16 ... capacitor voltage judgment unit, 17,127,176,226 ... relay input unit, 18,128,177,227
… Switching unit, 19,129… Capacitor voltage control unit, 20,130,17
9,229… Torque shock absorption processing unit, 21,131,180,230…
Current control processing unit, 22, 132, 181, 231 ... PWM output stop unit, 23
… Key switch, 126… speed judgment section, 178… inverter input current control section, 182… current sensor for inverter input, 2
28 ... iq0 control unit

Continuation of the front page (56) References JP-A-9-266695 (JP, A) JP-A-7-87605 (JP, A) JP-A-4-275002 (JP, A) (58) Fields studied (Int .Cl. ⁷ , DB name) B60L ^7/ 00-13/00 B60L 15/00-15/42 H02M 7/48 H02P 7/63

Claims (11)

(57) [Claims] 1. A relay circuit for opening and closing a power supply of a battery;
A capacitor at the subsequent stage of the relay circuit and connected in parallel to the battery, an inverter at the subsequent stage of the capacitor to supply the power of the battery to the permanent magnet synchronous motor, and a power-on control of the relay circuit, And a controller that performs motor control of the permanent magnet synchronous motor using the inverter thereafter.The controller is configured to control the permanent magnet synchronous motor by opening the relay circuit. Prior to restarting the power-on control and the motor control, the induced and accumulated electric charge of the capacitor is executed by a preceding control for consuming the permanent magnet synchronous motor, and thereafter, the power-on control and the power-on control are performed. An electric vehicle control device having means for shifting to motor control. 2. A relay circuit, comprising a main relay, an auxiliary relay and a resistor connected in parallel to the main relay, for opening and closing a power supply of a battery, a capacitor at a subsequent stage of the relay circuit and connected in parallel to the battery, An inverter that is provided at a stage subsequent to the capacitor and supplies electric power from the battery to the permanent magnet synchronous motor; and performs a power-on control of the relay circuit that turns on the main relay after the auxiliary relay. A controller that outputs a signal to control the power supply of the inverter to execute motor control, comprising: a unit that measures a terminal voltage of the capacitor; A voltage input monitoring means, and a motor control torque component current iq is compared with the terminal voltage and a predetermined voltage. Run the preceding motor control to a value corresponding to the difference, the terminal voltage and the predetermined voltage corresponding electric vehicle control apparatus characterized by a means for transition to the power-on control of the relay circuit. 3. A relay circuit, comprising a main relay, an auxiliary relay and a resistor connected in parallel to the main relay, for opening and closing the power supply of a battery, a capacitor at a subsequent stage of the relay circuit and connected in parallel to the battery, An inverter that is provided at a stage subsequent to the capacitor and supplies electric power from the battery to the permanent magnet synchronous motor; and performs a power-on control of the relay circuit that turns on the main relay after the auxiliary relay. A controller that outputs a signal to control the power supply of the inverter to execute motor control; a means for measuring a terminal voltage of the capacitor; and a rotation of the permanent magnet synchronous motor. Means for measuring a speed, wherein the controller inputs the terminal voltage and the rotation speed Means for monitoring, if the rotation speed is equal to or less than a predetermined rotation speed, means for shifting to power-on control of the relay circuit, and if the rotation speed exceeds the predetermined rotation speed, the motor control torque current iq is transmitted to the terminal. Means for executing a preceding motor control having a value corresponding to a difference between the voltage and the predetermined voltage, setting the terminal voltage to the predetermined voltage, and shifting to power-on control of the relay circuit. Electric vehicle control device. 4. The precedent motor control according to claim 2, wherein the preceding motor control is a control in which the permanent magnet synchronous motor outputs a positive torque when the terminal voltage is higher than the predetermined voltage. An electric vehicle control device characterized by the above-mentioned. 5. The precedent motor control according to claim 2, wherein the preceding motor control is such that the permanent magnet synchronous motor outputs a negative torque when the terminal voltage is lower than the predetermined voltage. An electric vehicle control device characterized by the above-mentioned. 6. The precedent motor control according to claim 2, wherein the preceding motor control is a control to set the torque component current iq to 0 (zero) after the terminal voltage reaches a predetermined voltage. Characteristic electric vehicle control device. 7. The system according to claim 2, wherein the predetermined voltage is a value obtained from the terminal voltage input from the terminal voltage measuring means when the main relay is turned on by the controller. An electric vehicle control device, characterized in that: 8. A relay circuit comprising a main relay, an auxiliary relay and a resistor connected in parallel to the main relay, for opening and closing the power supply of a battery, and a capacitor at a subsequent stage of the relay circuit and connected in parallel to the battery. And an inverter at the subsequent stage of the capacitor for supplying power from the battery to the permanent magnet type synchronous motor, and a power-on control of the relay circuit for turning on the main relay after the auxiliary relay, And a controller that outputs a control signal to control the power supply of the inverter to execute motor control of the permanent magnet synchronous motor, wherein the input current of the inverter is measured. A controller for input monitoring the input current; and a torque for controlling the motor. Means for executing a preceding motor control in which a current iq is set to a value corresponding to the input current, setting the input current to 0 (zero), and shifting to power-on control of the relay circuit. Electric vehicle control device. 9. A relay circuit comprising a main relay, an auxiliary relay connected in parallel to the main relay, and a resistor for opening and closing the power supply of a battery, and a capacitor provided at a subsequent stage of the relay circuit and connected in parallel to the battery. And an inverter at the subsequent stage of the capacitor for supplying power from the battery to the permanent magnet type synchronous motor, and a power-on control of the relay circuit for turning on the main relay after the auxiliary relay, Then, a controller that outputs a control signal to control the power supply of the inverter to execute motor control of the permanent magnet synchronous motor, wherein the controller has a torque of the motor control. While executing the preceding motor control in which the divided current iq is set to 0 (zero),
An electric vehicle control device having means for shifting to power-on control of the relay circuit. 10. The method of claim 2 or claim 3 or claim 8.
Or the controller according to any one of claims 9 to 12, wherein the controller controls the torque of the permanent magnet synchronous motor after turning on the main relay so as to prevent the output torque of the permanent magnet synchronous motor from suddenly changing. To
An electric vehicle control device comprising a torque shock absorbing means for gradually increasing from 0 or gradually decreasing from 0. 11. The method of claim 2 or claim 3 or claim 8.
10. The electric vehicle control device according to claim 9, wherein the controller has means for turning on the auxiliary relay again while the electric vehicle is running. 11.