JPH08107608A - Motor driver used also as battery charger and electric motor vehicle - Google Patents

Abstract

PURPOSE: To charge the battery of an electric motor vehicle without using any special purpose charger having large weight and volume. CONSTITUTION: A chopper 23 made of a transistor 24, etc., is connected in parallel with an inverter for driving a motor. At the time of charging a battery 10, a charging adapter 30 having a step-up reactor 31 is connected to a charging connector 27. When the adapter 30 is connected to the AC power source 32 of an external power source, a stand power source or a solar cell 43, a microcomputer identifies whether the external power source is the AC power source, the stand power source or the cell 43 according to the output signal from a photocoupler 37 and the measurement of a power source impedance, and controls on, off the transistor 14U of the one arm 17U of the inverter and the transistor 24 of the chopper 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor drive device that also serves as a battery charging device that charges a battery by using a part of a drive circuit that drives a motor using a battery as a DC power supply, and an electric vehicle using this device.

[0002]

2. Description of the Related Art For example, in an electric vehicle, a DC power source from a battery is converted into an AC power source and supplied to a motor such as a brushless motor or an induction motor, and this motor passes through a transmission, a differential gear and an axle. A wheel drive arrangement is provided. A rechargeable lead-acid battery is generally used as the battery.

When the battery discharges and the voltage drops, the electric power required to drive the motor cannot be obtained.
Conventionally, a charger is mounted on an electric vehicle. This charger is composed of a transformer that transforms the AC power supply voltage of the AC power supply and a rectifying / smoothing circuit that rectifies and smoothes the AC voltage from this transformer into a DC voltage. Its input terminal is connected to the charging connector. The output terminals are connected to both the positive and negative terminals of the battery. When charging the battery, the charger is connected to an external AC power source via the charging connector.

[0004]

In the conventional structure, a charger having a transformer or the like is required to charge the battery, and the transformer of this type of charger is large in weight and volume and needs a large installation space. In addition, there is a problem that the manufacturing cost increases, which is disadvantageous especially for electric vehicles.

It has been conventionally considered to mount a solar cell on an electric vehicle and charge the battery with a DC power supply from now on. In this case, however, the solar cell operates with the largest output power. It is necessary to provide a maximum power point tracking control device for controlling the operation at a point, which requires a wider space, which further increases the manufacturing cost.

The present invention has been made in view of the above circumstances. A first object of the present invention is to charge a battery without using a dedicated charger having a transformer having a large weight and volume. Moreover, it is an object of the present invention to provide a battery drive device / motor drive device capable of preventing abrupt charging assuming the battery to be over-discharged.

A second object of the present invention is to provide a battery charging device / motor capable of performing maximum power point tracking control without using a dedicated maximum power point tracking control device when charging a battery with a solar cell. In providing a drive device.

A third object of the present invention is to provide an electric vehicle using a battery drive and a motor drive.

[0009]

According to another aspect of the present invention, there is provided a motor drive for a battery charger and a motor, which has at least one arm formed by connecting in series two switching elements each having a flywheel diode. Is connected to a battery, an output terminal is connected to a motor, and a drive circuit for energizing and controlling the motor by turning on / off the switching element, and a flywheel diode for one arm of the drive circuit are used to charge the battery. A chopper circuit that is provided so as to form a rectifying circuit and has a switching element, a reactor that is connected to at least one of the arm of the drive circuit and one of the chopper circuits when charging the battery, and when the motor is operating. , ON / OFF control the switching element of the drive circuit, At the time of power supply, in a state where an external power supply is connected between the one arm and the chopper circuit via the reactor, a control means for controlling ON / OFF of the switching element of the one arm and the switching element of the chopper circuit, The present invention is characterized in that it is provided in the charging path of the battery, and is provided with a current limiting switching element which is controlled by the control means to limit the current when the external power source is an AC power source.

According to a second aspect of the present invention, there is provided a motor drive for a battery charger and a motor, which is equipped with a power supply identification sensor for identifying the type of the external power supply, and the control means controls the external power supply to be an AC power supply or a DC power supply according to the output of the power supply identification sensor. Identify the power source,
It is characterized in that it is configured so as to select a switching element to be on / off controlled according to the identification.

According to another aspect of the present invention, there is provided a battery charger / motor driver, wherein the control means performs power factor correction control when the external power source is identified as the AC power source, and the charging current when the external power source is identified as the DC power source. It is characterized in that it is configured to perform control.

According to another aspect of the present invention, there is provided a motor driving device for a battery charging device, wherein the control means, when the external power source is identified as a direct current power source, measures the impedance of the power source to determine whether the direct current power source is a solar cell. When it is determined to be a solar cell, the maximum power point tracking control is performed by software.

According to a fifth aspect of the present invention, there is provided a motor driving device for a battery charging device and a motor driving device, wherein when the external power source is an AC power source, the energizing phase of the current limiting switching element is gradually increased from substantially zero at the start of charging. It is characterized in that it is configured to control so as to perform.

An electric vehicle according to a sixth aspect is characterized by using the motor drive device also serving as the battery charging device according to any one of the first to fifth aspects.

[0015]

According to another aspect of the present invention, there is provided a battery charging device / motor driving device, wherein when the battery is being charged, the driving circuit 1
An external power supply is connected between the two arms and the chopper circuit via a reactor. Therefore, when the on / off control of the switching element of one arm and the chopper circuit is repeated, an electric current intermittently flows from the external power supply to the reactor to accumulate electromagnetic energy, and the electromagnetic energy is stored in the battery via the one arm and the chopper circuit. Will be given to you to charge it. Therefore, the battery can be charged only by controlling one arm and the chopper circuit by the control means without using a dedicated charger having a transformer with a large weight and volume.

In this case, since the current limiting switching element is provided in the charging path of the battery, the control means is
Assuming that the battery is over-discharged, the charging current is limited by controlling the current limiting switching element when the external power source is an AC power source to prevent rapid charging of the battery.

According to another aspect of the present invention, when the battery is charged, the control means discriminates whether the external power source is an AC power source or a DC power source, and performs on / off control according to the discrimination. Since a switching element is selected, either an AC power supply or a DC power supply can be used as an external power supply.

According to another aspect of the present invention, there is provided a battery charger / motor driver, wherein the control means performs power factor correction control when the external power source is an AC power source during charging of the battery. In addition, when the external power source is a DC power source, the charging current is controlled, so that an overvoltage is not applied to the battery.

According to another aspect of the present invention, there is provided a motor driving device for a battery charger as well, wherein the control means performs maximum power point tracking control by software when it determines that the DC power source is a solar cell, so that a dedicated maximum power point tracking is performed. It is not necessary to provide a control device.

According to another aspect of the present invention, in the motor driving device also serving as the battery charging device, the control means gradually increases the energization phase of the current limiting switching element from substantially zero at the start of charging when the external power source is an AC power source. The charging current is controlled so as to increase gradually because the charging current is increased.

According to the electric vehicle of the sixth aspect, since the battery driving device / motor driving device according to any one of the first to fifth aspects is used, it is possible to reduce the size and weight of the mounted object. Accordingly, the one-charge traveling distance can be lengthened, and conversely, more batteries can be mounted to reduce the size and weight, and the one-charging traveling distance can be lengthened.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an electric vehicle will be described below with reference to the drawings. First, in FIG. 7 showing the overall configuration, an electric motor 1 is equipped with an induction motor 2 as a motor. As shown in FIG. 1, the induction motor 2 includes a stator 3 having stator coils 3U, 3V and 3W having a plurality of phases, for example, three phases, and a rotor (not shown). Then, by the induction motor 2, the axles 7, 7 of the rear wheels 6, 6 are transmitted via the transmission 4 and the differential gear 5.
Is driven. The axles 9 and 9 of the front wheels 8 and 8 of the electric vehicle 1 are not driven. Then, the electric vehicle 1 can be charged with, for example, a lead storage battery or the like.
A battery 10 having a 30 volt rating is mounted, and a DC power source from the battery 10 is converted into an AC power source by a battery charger / motor driving device 11 and supplied to the induction motor 2.

Now, a specific structure of the motor drive device 11 also serving as the battery charger will be described with reference to FIG. The inverter circuit 12 as a drive circuit includes NPN type transistors 13U, 13V, 1 which are six switching elements.
3W and 14U, 14V, 14W is configured by connecting three-phase bridge, flywheel diode 15U, 15V, 15W between the collector and the emitter respectively.
And 16U, 16V, 16W are connected, thus having three arms 17U, 17V and 17W. The input terminals 18 and 19 of the inverter circuit 12 are connected to the positive and negative terminals of the battery 10 via the DC buses 20 and 21, respectively, and the output terminals 22U, 22V and 22W are the stator coils 3U of the induction motor 2. , 3V and 3
It is connected to each one terminal of W. The stator coil 3
The other terminals of U, 3V and 3W are commonly connected.

The chopper circuit 23 comprises an NPN type transistor 24 and a diode 2 as switching elements.
In the transistor 24, the collector is connected to the DC bus 20 via the diode 25, the emitter is connected to the DC bus 21, and the diode 26 is connected between the collector and the emitter.
The charging connector 27 has four terminals 27a to 27d, the terminal 27a is connected to the output terminal 22U of one arm 17U of the inverter circuit 12 via the charging line 28, and the terminal 27b is of the chopper circuit 23. It is connected to the collector of the transistor 24, that is, the power supply terminal 23a via the charging line 29. As a result, the flywheel diodes 15U and 16U of one arm 17U forming a part of the inverter circuit 12 and the diodes 25 and 26 of the chopper circuit 23 constitute a full-wave rectification circuit in which the charging lines 28 and 29 are on the AC input side. To do.

The charging adapter 30 has six terminals 30a.
30 to 30f and a boosting reactor 31, the reactor 31 is provided between the terminals 30e and 30c.
Are connected between terminals 30a and 30f and between terminals 30b and 3
0d are connected to each other. The charging adapter 30
The positive (+) side terminal 30a and the negative (-) side terminal 30b of
As will be described later, the terminals 32a and 32b of the AC power source 32 as an external power source, the positive (+) side terminal 33a and the negative (−) side terminal 33b of the stand power source 33, or the positive (+) side terminal 43a of the solar cell 43 and Negative (-) side terminal 43b
It is designed to be connected to and detachable from.

In this case, the station power source 33 is a power source from a quick charging station which is installed on the street like a gas station and supplies a DC power source, and includes a similar type. The solar cell 43 is mounted on the electric vehicle 1 so as to receive sunlight.

The DC voltage detector 34 is composed of, for example, a voltage / frequency converter, is connected between the DC buses 20 and 21, and detects the terminal voltage of the battery 10. The input current detector 35 is arranged on the charging line 29 and detects the current flowing through the charging line 29 (current flowing through the reactor 31 as described later). The charging current detector 36 is arranged on the DC bus 20 and detects the charging current flowing through the battery 10. The input current detector 35 and the charging current detector 36 are Hall element type current transformers capable of detecting both alternating current and direct current.

The photocoupler 37, which is a power supply identification sensor, is
It has a light emitting diode 37a and a phototransistor 37b, and the light emitting diode 37a is connected between terminals 27d and 27b of the charging connector 27 via a resistor 38 in series. The emitter of the phototransistor 37b is grounded, and the connector is connected to the DC power supply line 40 to which the DC voltage + Vc is applied via the resistor 39. The collector of the phototransistor 37b becomes the output terminal of the photocoupler 37.

Now, the microcomputer 41 as a control means has a DC voltage detector 34, an input current detector 35, a charging current detector 36 and a photocoupler 37 at each input port.
Output terminals are connected to each other, and each output port is connected to each input terminal of the photocoupler type gate drive circuit 42, which operates as described later. The output terminals of the gate drive circuit 42 are connected to the transistors 13U to 13W and 14U to 14W of the inverter circuit 12 and the base (gate) of the transistor 24 of the chopper circuit 23, respectively. One output port of the microcomputer 41 is connected to the control terminal of the transmission 4 as shown in FIG.

On the other hand, the input voltage detector 44 is composed of, for example, a voltage / frequency converter, and has a charging connector 27.
Is connected between the terminals 27b and 27c of the microcomputer and detects the DC power supply voltage applied between the terminals 27b and 27c, and its output terminal is connected to the input port of the microcomputer 41. A bidirectional three-terminal thyristor (hereinafter referred to as a triac) 45, which is a current limiting switching element, is a terminal 2 of the charging connector 27.
It is connected between 7c and 27d. One output port of the microcomputer 41 is connected to the input terminal of the photocoupler type gate drive circuit 46, and the output terminal of the gate drive circuit 46 is connected to the gate of the triac 45.

Next, the operation of this embodiment will be described with reference to FIGS. 2 to 6. First, the operation of the electric vehicle 1 during traveling will be described. That is, the microcomputer 41
The energization timing signals for the transistors 13U to 13W and 14U to 14W of the inverter circuit 12 are output and given to the base drive circuit 42. The base drive circuit 42 determines the bases of the transistors 13U to 13W and 14U to 14W according to the energization timing signal. A base signal (gate signal) is applied to the transistors in a predetermined order to control on / off of the transistors 13U to 13W and 14U to 14W. As a result, the inverter circuit 12
An AC voltage is created from the DC voltage of the battery 10 and applied to the induction motor 2, the induction motor 2 rotates, and the electric vehicle 1 runs.

In this case, the microcomputer 41
Transistor 13U according to the opening degree of the accelerator (not shown)
To 13W or 14U to 14W by PWM control,
Thus, the rotation speed of the induction motor 2 is controlled, and a control signal is given to the transmission 4 to control the speed ratio thereof.

Now, the operation of charging the battery 10 will be described. At this time, the terminals 30c, 30d, 30e and 30f of the charging adapter 30 are connected to the charging connector 2.
7 terminals 27a, 27b, 27c and 27d.

(A) When the external power source is an AC power source (commercial power source) of single-phase 200 V. When the terminals 30a and 30b of the charging adapter 30 are connected to the terminals 32a and 32b of the AC power source 32, the light emitting diode of the photocoupler 37 is connected. As shown in FIG. 4A, the AC power supply voltage Vac is supplied to 37a, so that the light emitting diode 37a thereof intermittently emits light. That is, the light emitting diode 37a repeatedly emits light during a positive half-wave of the AC power supply voltage Vac and stops emitting light during a negative half-wave, and accordingly, the phototransistor 37b repeatedly turns on and off. And the phototransistor 3
The output signal S of the photocoupler 37, which is the collector potential of 7b
Becomes low level when turned on and high level when turned off, and this is given to the microcomputer 41.

When the microcomputer 41 detects that the output signal S from the photocoupler 37 repeats the low level and the high level, it determines that the charging is started and also identifies that the external power source is the AC power source 32. 2, one arm 17U of the inverter circuit 12
14U and transistors 13U to 13W and 14 other than the transistor 24 of the chopper circuit 23
Turn off V and 14W. Further, as shown in FIG. 4B, the microcomputer 41 waveform-shapes the output signal S from the photocoupler 37 to obtain a rectangular wave signal P, and from the rising and falling edges thereof, the zero-cross point of the AC power supply voltage Vac. To detect.

When the microcomputer 41 detects the zero-cross point of the AC power supply voltage Vac, the microcomputer 41 detects P
By the LL control, a sine wave reference (voltage) signal VR synchronized with the AC power supply voltage Vac is created as shown in FIG. The microcomputer 41 determines the polarity of the AC power supply voltage Vac from the reference signal VR, and based on this, performs the following control.

The microcomputer 41 has an AC power source 3
When it is determined that the charging is performed by 2, the initial charging operation is started. That is, when the AC power supply voltage Vac is a positive (+) half-wave, the microcomputer 41 determines that the chopper circuit 23
When the AC power supply voltage Vac has a negative (-) half-wave, the transistor 24 is turned off and the transistor 14U of one arm 17U is turned on. Conversely, the transistor 14U is turned off and the transistor 24 is turned on. Further, the microcomputer 41 first gives a gate signal to the triac 45 near the zero crossing point where the AC power supply voltage Vac (see FIG. 3A) changes from the negative half wave to the positive half wave. Fig. 3 shows the energization phase of
As shown in (b), it becomes substantially zero. After that, the microcomputer 41 controls the gate signal applied to the triac 45 so that the energization phase of the triac 45 gradually increases as shown in FIG.

Thus, while the triac 45 is on, a current flows through the reactor 31, electromagnetic energy is accumulated in the reactor 31, and the triac 4
When 5 is turned off, the electromagnetic energy is applied to the battery 10, and the battery 10 is charged with the boosted voltage. Therefore, the AC power supply current Iac of the AC power supply 32 is as shown in FIG. It gradually increases as shown in. The principle of charging the battery 10 will be described in detail later. The charging current Ib for the battery 10 is detected by the charging current detector 36 and given to the microcomputer 41. When the charging current Ib reaches a predetermined value, the microcomputer 41 shifts to the next normal charging operation. To do.

That is, when the AC power supply voltage Vac is a positive (+) half-wave, the microcomputer 41 first turns off the transistor 24 of the chopper circuit 23, turns on the transistor 14U of one arm 17U, and The triac 45 of the chopper circuit 23 is turned on. As a result, the triac 45, the reactor 31, the charging line 2
8, transistor 14U, DC bus 21, diode 2
The AC power supply current Iac flows through the reactor 31 through the path of 6 and the charging line 29, and electromagnetic energy is accumulated in the reactor 31. AC power supply current I flowing through this reactor 31
ac is detected by the input current detector 35 and the detected current I
It is given to the microcomputer 41 as d. still,
The detection current Id is actually converted into a voltage and given to the microcomputer 41, but here,
For convenience of description, the detection current Id will be described.

When the detection current Id increases due to the ON state of the transistor 14U and becomes larger than the reference signal VR, the microcomputer 41 causes the transistor 1
Turn off 4U. As a result, the electromagnetic energy stored in the reactor 31 passes through the charging line 28, the flywheel diode 15U, and the DC bus 20 to the battery 10.
Then, the battery 10 is charged with the boosted voltage.

Thereafter, the detection current I of the input current detector 35 is detected.
When d decreases and becomes smaller than the reference signal VR, the microcomputer 41 turns on the transistor 14U again. After that, the same operation is repeated. Therefore, the gate signal Sy applied to the transistor 14U
Is as shown in FIG.

When the AC power supply voltage Vac is a negative (-) half-wave, the microcomputer 41 has one arm 17
The transistor 14U of U is turned off, and the chopper circuit 23
Turning on the transistor 24 of the TRIAC 4
Turn 5 on. The on / off operation of the transistor 24 in this case is similar to that of the transistor 14U described above. Therefore, the gate signal Sz given to the transistor 24 becomes as shown in FIG.

That is, the microcomputer 41 shown in FIG.
As shown in (f), the transistors 14U and 24 are on / off controlled so that the detection current Id follows the reference signal VR, whereby the detection current Id has a sinusoidal waveform in phase with the AC power supply voltage Vac. The AC power supply current Iac is controlled as shown in FIG.

The terminal voltage of the battery 10 is detected by the DC voltage detector 34 and applied to the microcomputer 41. The microcomputer 41 sets the terminal voltage of the battery 10 to a specified value. When it reaches, it is judged that the charging is completed and the transistors 14U, 24
Is turned off, and a notification device (not shown) is operated to notify the completion of charging.

(B) When the external power source is a DC power source In the circuit state shown in FIG. 2, the positive side terminal 30a and the negative side terminal 30b of the charging adapter 30 are connected to the positive side terminal 33a and the negative side terminal 33b of the stand power source 33 or the sun. When connected to the positive side terminal 43a and the negative side terminal 43b of the battery 43, the DC power supply voltage Vdc (see FIG. 5 (a)) is applied to the photocoupler 37.
Is supplied to the light emitting diode 37a of
7a emits light, and accordingly, the phototransistor 37b
Turns on and the output signal S becomes low level. in this case,
When the external power supply is the stand power supply 33 or the solar battery 43 which is a DC power supply, unlike the AC power supply 32, the light emitting diode 37a continuously emits light, so that the output signal S remains low level.

The microcomputer 41 outputs the output signal S
Is continuously set to the low level, it is determined that the charging is started, the external power supply is identified as the DC power supply, and the DC power supply determination operation is performed. That is, the microcomputer 41 turns on the triac 45, and as shown in FIG. 5B, a pulse signal (gate signal) of, for example, 100 μsec is applied to the base of the transistor 14U.
Pa is applied to turn on the transistor 14U. Then, a current flows through the reactor 31 and the DC power supply voltage Vd
c is lowered as shown in FIG. After that, when the transistor 14U is turned off, the DC power supply voltage Vdc returns to the original state.

Therefore, the microcomputer 41 causes the voltage value V1 of the DC power supply voltage Vdc immediately after the transistor 14U is turned on (immediately after the rise of the pulse signal Pa) and the voltage value V1 immediately before it is turned off (immediately before the fall of the pulse signal Pa) to the time T2. Of the voltage value V2 is detected through the input voltage detector 44, and it is determined whether the voltage value V2 is lower than the voltage value V1 by 20% or more, for example. That is, the solar cell 43
Since its impedance is higher than that of the stand power supply 33, the voltage drop when current is taken is significant,
For example, when the current is taken out for 100 μsec, the decrease of the voltage value V2 with respect to the voltage value V1 reaches 20% or more. From the above, the microcomputer 41 determines whether the DC power source is the stand power source 33 or the solar battery 43.

(B-1) When the DC power supply is the stand power supply 33 of 180 V, the microcomputer 41 first sets the triac 45.
And the transistor 14U of one arm 17U is turned on, whereby an input current flows through the reactor 31 and electromagnetic energy is accumulated. The transistor 14U is the microcomputer 41.
ON / OFF control is performed as will be described later. Therefore, when the transistor 14U is turned off,
The electromagnetic energy accumulated in the reactor 31 is the charging line 2
8, flywheel diode 15U and DC bus 20
Is supplied to the battery 10 via the battery, and the battery 10 is charged with the boosted DC voltage.

In this case, the microcomputer 41
The detection current of the charging current detector 36 that detects the charging current Ib of the battery 10 is input, and when the detected charging current Ib is larger than the set value, the on / off duty of the transistor 14U is reduced. To reduce the charging voltage for the battery 10, and conversely, the charging current I
When b is smaller than the set value, the on / off duty of the transistor 14U is set to be large, and the charging voltage for the battery 10 is controlled to be large.

Thereafter, the microcomputer 41 repeats the same operation to charge the battery 10 by the stand power supply 33, and the detection voltage of the DC voltage detector 34 for detecting the terminal voltage of the battery 10. Reaches a specified value, it is determined that the charging is completed, the transistor 14U is turned off, and a notifying device (not shown) is informed of the completion of charging.

(B-2) DC power source is 160 V to 3
In the case of the solar cell 43 of 00 volt, the microcomputer 41 turns on the triac 45 and turns on / off the transistor 14U to charge the battery 10 as in the case of the stand power source 33, and performs maximum power point tracking control (MPPT control). ).

FIG. 6 is a flowchart showing the principle of maximum power point tracking control. The microcomputer 41
First, electric power is calculated from the input voltage detected by the input voltage detector 44 and the input current detected by the input current detector 35, and this is stored in the RAM. Microcomputer 41
Is next the judgment step S1 of "power increase?", And here it is judged whether or not the power calculated this time is more than the power calculated in the previous time and stored in the RAM, and "YES". When it is determined (increase), the process proceeds to a determination step S2 of "increased voltage command value last time?"

In this judgment step S2, the microcomputer 41 judges whether or not the charging voltage command value for the battery 10 was increased last time.
When it is determined to be "ES" (increase), the process proceeds to step S3 of "increasing voltage command value". Then, in this processing step S3, the microcomputer 41 increases the charging voltage command value so as to increase by a constant voltage, whereby the ON / OFF duty of the transistor 14U is increased by a constant rate and the battery 10 is increased. Increase the charging voltage for the constant voltage.

On the other hand, when the microcomputer 41 judges "NO" (decrease) in the judgment step S1 of "power increase?", The judgment step S of "previous voltage command value increase?"
4, the same judgment as the judgment step S2 is made here. When the microcomputer 41 determines "YES" (increase) in this determination step S4, it shifts to a "voltage command value decrease" processing step S5, where the charge voltage command value is decreased so as to decrease by a constant voltage. I will let you. As a result, the microcomputer 41
Reduces the on / off duty of the transistor 14U by a certain ratio to reduce the charging voltage for the battery 10 by a certain voltage.

Further, the microcomputer 41 determines "NO" (decrease) in the determination step S2 of "increased voltage command value last time?"
If it is determined that the voltage command value is reduced, step S
5, and when it is determined to be "NO" (decrease) in the determination step S4 for "previous voltage command value increase?", The process proceeds to "voltage command value increase" processing step S3.

As described above, the microcomputer 41
Is to control the solar cell 43 to operate at the maximum power point by software processing, and then charge when the detection voltage of the DC voltage detector 34 that detects the terminal voltage of the battery 10 reaches a specified value. When it is determined that the charging is completed, the transistor 14U is turned off, and a notifying device (not shown) is informed of the completion of charging.

According to the present embodiment constructed and operated as described above, the following effects can be obtained. That is, when the battery 10 is charged, the output terminal 22U of one arm 17U of the inverter circuit 12, which is the drive circuit, and the chopper circuit 2 are charged.
An external power source (AC power source 32, stand power source 33, or solar cell 43) is connected to the power source terminal 23a of the transistor 3 via the reactor 31, and the transistors 14U and 24 are connected.
Since both or one of them is controlled to be turned on and off, an electric current intermittently flows from the external power supply to the reactor 31 to accumulate electromagnetic energy, and the electromagnetic energy is reduced to 1
It is given to the battery 10 via the one arm 17U and the chopper circuit 23 and is charged.

Therefore, unlike the prior art, even if a dedicated charger having a transformer of large weight and volume is not used,
The chopper circuit 23 is additionally provided to add a microcomputer 41.
The battery 10 can be charged only by controlling
Therefore, the manufacturing cost can be reduced, and the size and weight of the mounted object in the machine room of the electric vehicle 1 can be reduced.
The one-charge traveling distance can be lengthened, and conversely, the number of batteries 10 can be increased as much as the reduction in size and weight, so that the one-charge traveling distance can be lengthened. Further, even if an external power source having a lower voltage (for example, 200 V, 180 V, or 160 V to 300 V) than the battery 10 rated at 330 V, the battery 10 can be easily charged. Therefore, it is extremely advantageous for the user.

Further, when charging the battery 10, the microcomputer 41 discriminates whether the external power source is the AC power source 32 or the DC power source by the output signal of the photocoupler 37, and when discriminating from the AC power source 32, one arm is provided. Transistors 13U to 13W and 14 other than the 17U transistor 14U and the chopper circuit 23 transistor 24
Turn off V and 14W to turn on transistors 14U and 24
Is selected to perform on / off control, and when the external power supply is identified as a DC power supply, the transistors 13U to 13E and 14 other than the transistor 14U of one arm 17U are selected.
Turn off V, 14W and 24 to turn on transistor 14U
Only selected and controlled to turn on and off. Therefore, when charging the battery 10, the user only has to connect the charging adapter 30 to an external power supply, and does not need to switch between running and charging, and the external power supply is an AC power supply. The battery 10 can be automatically charged by any of the 32 and DC power supplies, and there is no need to perform an AC / DC switching operation, which is extremely convenient in use and also requires AC / DC switching means. There is no need, and a simple structure can be achieved, and there is no erroneous switching operation.

Furthermore, when charging the battery 10,
When the external power supply is the AC power supply 32, the microcomputer 41 detects the zero-cross point of the AC power supply voltage Vac based on the output signal of the photocoupler 37, and based on this, the reference signal synchronized with the AC power supply voltage Vac. VR is obtained, and the input current Id of the input current detector 35 for detecting the AC power supply current Iac is made to follow the reference voltage VR.

Therefore, even if the boosting reactor 31 is used, the power factor of the AC power source 32 can be controlled to be improved.
The power supply harmonics can be reduced, and at the same time, the charging current for the battery 10 can be controlled.

When the external power source is identified as the AC power source 32 when the battery 10 is being charged, the microcomputer 41 gradually increases the energization phase of the triac 45 provided in the charging path of the battery 10 from substantially zero. Since the initial charging operation is controlled so that
Even if the battery 10 is over-discharged, it is possible to prevent the battery 10 from being charged rapidly,
There is no adverse effect on 0.

Further, when the external power source is identified as the DC power source during charging of the battery 10, the microcomputer 41 further measures the power source impedance to determine whether the DC power source is the stand power source 33 or the solar battery 43. I chose When the DC power source is the stand power source 33, the microcomputer 41 operates the battery 10
Since the on / off duty of the transistor 14U of one arm 17U is changed to small or large depending on whether the charging current of is larger or smaller than the set value, the charging voltage for the battery 10 can be made appropriate, The charging voltage does not become an overvoltage and adversely affects the battery 10, and control without power loss can be performed.

Further, when the DC power supply is determined to be the solar cell 43, the microcomputer 41 performs the maximum power point tracking control of the solar cell 43 by software processing, so that the solar cell 43 can be efficiently used. It can be operated, and unlike the prior art, it is not necessary to provide a dedicated maximum power point tracking control device, and accordingly, the installation space in the electric vehicle 1 can be widened and the manufacturing cost can be reduced.

Further, the photocoupler 37 as the power source identification sensor has the AC power source voltage Va of the AC power source 32 during the power factor correction control when the external power source is the AC power source 32.
Since it is also used as a zero-cross point detection sensor for obtaining the reference signal VR synchronized with c, it is not necessary to provide a special zero-cross point sensor, and the configuration can be further simplified.

Since the boosting reactor 31 is configured as the charging adapter 30, the weight and volume of the load in the machine room of the electric vehicle 1 can be further reduced, which is more advantageous for the electric vehicle 1. become.

In the above embodiment, the induction motor 2 drives the axle 7 of the wheel 6 through the transmission 4 and the differential gear 5, but the induction motor 2 directly drives the axle 7. May be.

Further, in the above embodiment, the induction motor 2 is used as the motor, but instead of this, the induction motor 2 is used.
A phase motor, a brushed DC motor, a brushless DC motor or a reluctance motor may be used, and in this case, the drive circuit has one arm in which two transistors, which are switching elements having flywheel diodes, are connected in series. Some have only this (for example, a DC motor with a brush), and therefore, a drive circuit having one or more arms is a target.

Further, although the triac 45 is provided as the current limiting switching element in the above embodiment, two antiparallel connected thyristors may be provided instead, or two antiparallel connected two thyristors may be provided. Alternatively, a photo thyristor or a photo triac may be provided.

In addition, the present invention is not limited to the above-described embodiments, and is applicable not only to electric vehicles but also to all devices requiring a motor drive device for driving a motor using a battery as a power source. As a matter of course, the present invention can be appropriately modified and implemented without departing from the scope of the invention.

[0071]

Since the present invention is as described above, it has the following effects. According to the motor drive device that also functions as the battery charging device according to claim 1, when charging the battery, an external power supply is connected between one arm of the drive circuit and the chopper circuit via the reactor, and the current is limited to the charging path. Since the switching element for the
When the ON / OFF control of the switching element of one arm and the chopper circuit is repeated, a current flows intermittently from the external power supply to the reactor to accumulate electromagnetic energy, and the electromagnetic energy is given to the battery via the one arm and the chopper circuit. Therefore, the battery can be charged only by controlling one arm and the chopper circuit by the control means without using a dedicated charger having a transformer with a large weight and a large volume. In addition, when the external power source is an AC power source, it is possible to prevent the battery from being rapidly charged.

According to the second aspect of the present invention, there is provided a motor drive device for a battery charger and a battery charger. When the battery is charged, the control means discriminates whether the external power source is an AC power source or a DC power source, and performs on / off control according to the discrimination. Since the switching element is selected, either an AC power supply or a DC power supply can be used as an external power supply. In this case, there is no need to switch between AC and DC, which is extremely convenient in use and can be used in a correct operation. There is no fear.

According to the third aspect of the present invention, there is provided a battery charger / motor driving device. When the battery is charged, the control means performs the power factor correction control when the external power source is an AC power source. The harmonics can be reduced, and when the external power supply is a DC power supply, the charging current is controlled, so that an overvoltage is not applied to the battery.

According to another aspect of the present invention, there is provided a motor drive for a battery charger and a controller. When the DC power supply is determined to be a solar cell, the control means performs maximum power point tracking control by software. It is not necessary to provide a tracking control device.

According to another aspect of the present invention, in the battery driving device / motor driving device, when the external power source is an AC power source, the control means gradually changes the energization phase of the current limiting switching element from substantially zero at the start of charging. Therefore, the charging current is controlled so as to gradually increase, and rapid charging of the battery can be prevented.

According to the electric vehicle of the sixth aspect, the battery driving device and the motor driving device according to any one of the first to fifth aspects are used. Therefore, it is possible to reduce the size and weight of the mounted object, Accordingly, the one-charge traveling distance can be lengthened, and conversely, more batteries can be mounted to reduce the size and weight, and the one-charging traveling distance can be lengthened.

[Brief description of drawings]

FIG. 1 is an electrical configuration diagram showing an embodiment of the present invention.

FIG. 2 is an electrical configuration diagram during battery charging.

FIG. 3 is a waveform diagram of each part at the time of initial charging operation with an AC power source for a battery.

FIG. 4 is a waveform diagram of each part during the normal charging operation.

[Figure 5] Waveform diagram of each part when measuring the power supply impedance

FIG. 6 is a flowchart showing the contents of maximum power point tracking control.

FIG. 7 is an explanatory diagram of the configuration of an electric vehicle.

[Explanation of symbols]

In the drawing, 1 is an electric vehicle, 2 is an induction motor (motor), 3 is a stator, 3U to 3W are stator coils, 10 is a battery, 11 is a battery charger / motor drive device, 12 is an inverter circuit (drive circuit), 1
3U to 13W and 14U to 14W are transistors (switching elements), 15U to 15W and 16U to 16W are flywheel diodes, and 17U to 17
W is an arm, 18 and 19 are input terminals, 22U to 22
W is an output terminal, 23 is a chopper circuit, 24 is a transistor (switching element), 27 is a charging connector, 30
Is a charging adapter, 31 is a boosting reactor, 32 is an AC power supply (external power supply), 33 is a stand power supply (external power supply,
DC power supply), 34 is a DC voltage detector, 35 is an input current detector, 36 is a charging current detector, 37 is a photocoupler (power supply identification detection sensor, zero-cross point detection sensor), 41 is a microcomputer (control means), 43 is a solar cell (external power source, DC power source), 44 is an input voltage detector, 45
Indicates a bidirectional three-terminal thyristor (switching element for current limitation).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaki Hirata 991, Anada-cho, Seto-shi, Aichi Factory, Toshiba Aichi Co., Ltd. Within

Claims (6)

[Claims] 1. A switching element comprising: one or more arms having two switching elements each having a flywheel diode connected in series; an input terminal connected to a battery; and an output terminal connected to a motor. A drive circuit for controlling energization of the motor by turning on and off, and a chopper circuit provided with a switching element to form a rectifier circuit for charging the battery together with a flywheel diode of one arm of the drive circuit, At least one reactor of the drive circuit at the time of charging the battery and a reactor connected to one of the chopper circuits, and a switching element of the drive circuit is on / off controlled during operation of the motor, and at the time of charging the battery, The reactor is provided between the one arm and the chopper circuit. Control means for controlling ON / OFF of the switching element of the one arm and the switching element of the chopper circuit in a state in which an external power source is connected via an external power source; A motor drive device also serving as a battery charging device, comprising a current limiting switching element that is controlled by a control means to limit a current. 2. A power supply identification sensor for identifying the type of the external power supply, and the control means identifies whether the external power supply is an AC power supply or a DC power supply based on the output of the power supply identification sensor,
2. The motor drive device for a battery charger / motor according to claim 1, wherein the switching device to be turned on / off is selected according to the identification. 3. The control means is configured to perform power factor correction control when the external power supply is identified as an AC power supply, and to perform charging current control when the external power supply is identified as a DC power supply. The motor drive device also serving as the battery charging device according to claim 2. 4. The control means, when the external power supply is identified as a direct current power supply, determines whether the direct current power supply is a solar cell by measuring the impedance of the power supply. 4. The motor drive device for a battery charging device combined with a battery charging device according to claim 3, wherein the motor drive device is configured to perform maximum power point tracking control. 5. The control means is configured to control the energizing phase of the current limiting switching element to gradually increase from substantially zero at the start of charging when the external power source is an AC power source. The motor driving device for a battery charging device according to claim 1, wherein the motor driving device also serves as a battery charging device. 6. An electric vehicle using the battery charger / motor drive device according to claim 1. Description: