JP4747933B2 - Power supply device and vehicle equipped with the same - Google Patents

Description

  The present invention relates to a power supply device and a vehicle including the same.

Conventionally, as this type of power supply device, a device that boosts the voltage of a DC power supply by a boost converter having two switching elements and a reactor and supplies the boosted voltage to an electric load has been proposed (for example, see Patent Document 1). In this device, the on-time of the two switching elements is duty-controlled based on the voltage command on the boost side.
WO 03/056694 A1

  In the above-described power supply device, when the electric power input / output by the electric device connected to the booster side changes suddenly, the booster converter has low responsiveness, which may cause a voltage drop or an overvoltage on the booster side. The voltage drop on the boosting side hinders the desired drive of the electric device, and the overvoltage may cause damage to the elements of the circuit provided between the DC power supply and the electric device.

  The power supply device of the present invention and a vehicle equipped with the power supply device are intended to suppress a voltage drop on the boost side of the boost converter. Another object of the power supply device of the present invention and a vehicle including the same is to suppress overvoltage on the boost side of the boost converter. Furthermore, it is an object of the power supply device of the present invention and a vehicle equipped with the power supply device to ensure the driving of the electrical equipment. Alternatively, a power supply device according to the present invention and a vehicle including the power supply device have an object of suppressing breakage and damage of the element.

  The power supply device of the present invention and a vehicle including the same employ the following means in order to achieve at least a part of the above-described object.

The first power supply device of the present invention includes:
A power supply device that exchanges power with electrical equipment,
DC power supply,
A boost converter capable of boosting the voltage of the DC power supply and supplying the boosted voltage to the electrical device;
A diode connected in parallel to the boost converter in a forward direction with respect to the electrical device as viewed from the positive electrode of the DC power supply;
It is a summary to provide.

  In the first power supply device of the present invention, when the voltage on the boosting side of the boost converter drops and becomes less than the voltage of the DC power supply, the voltage of the DC power supply acts on the electrical equipment via the diode. The voltage on the boosting side can be made higher than the voltage of the DC power supply. As a result, it is possible to suppress the voltage on the boosting side of the boosting converter from dropping below the voltage of the DC power supply, and it is possible to ensure driving of the electric device. Here, the electrical device may be any device as long as it can exchange power with the power supply device.

The second power supply device of the present invention is
A power supply device that exchanges power with electrical equipment,
DC power supply,
A boost converter capable of boosting the voltage of the DC power supply and supplying the boosted voltage to the electrical device;
A capacitor connected to a boost side terminal of the boost converter;
A bypass circuit for bypassing the boost converter from the DC power supply to the capacitor;
It is a summary to provide.

  In the second power supply device of the present invention, the capacitor connected to the booster side terminal of the boost converter functions as a bypass circuit that bypasses the boost converter from the DC power supply, thereby causing an unexpected overvoltage or voltage drop of the capacitor. Can deal with. For example, if a diode connected in the forward direction with respect to the electrical equipment as viewed from the positive electrode of the DC power supply is used as the “bypass circuit”, the diode when the voltage on the boost side of the boost converter drops below the voltage of the DC power supply Since the voltage of the DC power supply acts on the capacitor side via the capacitor, the voltage of the capacitor can be made higher than the voltage of the DC power supply. As a result, it is possible to suppress the voltage of the capacitor from dropping below the voltage of the DC power source, and to ensure the driving of the electric device. Note that even in the second power supply device, the electrical device may be any device as long as it can exchange power with the power supply device.

  In the first power supply device of the present invention and the second power supply device of the present invention having a diode as a bypass circuit, a switching element connected in parallel with the diode and a voltage for detecting a voltage on the boost side of the boost converter When the detected voltage reaches the first voltage or higher, the switching element is turned on, and when the detected voltage is lower than the second voltage lower than the first voltage. Switch on / off means for turning off the switching element may be provided. In this way, it is possible to suppress the voltage on the boost side of the boost converter from exceeding the first voltage. As a result, it is possible to suppress an overvoltage on the boosting side of the boost converter, and it is possible to suppress damage or breakage due to an overvoltage of an element connected to the boosting side of the boost converter.

  In the first or second power supply device of the present invention having a switching element in parallel with such a diode, a resistor connected in series to the diode may be provided. Further, the diode may be connected to an intermediate tap of a reactor included in the boost converter. In these cases, voltage drop due to resistance or reactor can be expected.

  In the first or second power supply device of the present invention, the boost converter may include a relay that disables the boost function. In this way, when an abnormality occurs, it can be dealt with. In this case, the relay may be connected in series with a reactor of the boost converter.

The vehicle of the present invention
An electric motor that outputs driving force for traveling;
The first or second power supply device according to any one of the above-described aspects that exchanges electric power with the electric motor as the electric device, that is, basically a power supply device that exchanges electric power with the electric device, A power supply; a boost converter capable of boosting the voltage of the DC power supply and supplying the boosted voltage to the electrical device; and a diode connected in parallel to the boost converter in a forward direction with respect to the electrical device as viewed from the positive electrode of the DC power supply A first power supply device according to the present invention, or a power supply device for exchanging electric power with an electric device, the step-up converter capable of boosting the voltage of the DC power source and supplying the voltage to the electric device. A capacitor connected to a booster side terminal of the boost converter, and a bypass circuit bypassing the boost converter from the DC power supply to the capacitor A second power supply device of the present invention comprising a
It is a summary to provide.

  Since the vehicle of the present invention includes the first or second power supply device of the present invention according to any one of the above-described aspects, the effect of the first or second power supply device of the present invention, for example, boosting of the boost converter The effect that can suppress the voltage drop on the side, the effect that can ensure the drive of the electrical equipment accompanying this, the effect that can suppress the overvoltage on the boost side of the boost converter, and the damage or breakage of the element accompanying this It is possible to achieve the same effects as the effect of suppressing the voltage, the effect of coping with unexpected overvoltage and voltage drop of the capacitor, and the like.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of a configuration of an in-vehicle power supply device 20 as an embodiment of the present invention. As shown in the figure, the power supply device 20 of the embodiment is connected to two motors MG1 and MG2 that output driving power via inverters 11 and 12, and includes a battery 22 as a DC power source, A boost converter 30 that boosts the voltage and supplies it to the two motors MG1 and MG2 side, or steps down the voltage on the motor MG1 and MG2 side and supplies it to the battery 22 side, and a function for stopping the function of the boost converter 30 A relay 26, a smoothing capacitor 42 that is arranged on the boosting side (two motors MG1, MG2 side) of the boosting converter 30 and smoothes the voltage on the boosting side, an adjustment circuit 46 that adjusts the voltage on the smoothing capacitor 42 side, and a device And an electronic control unit 50 for controlling the whole.

  The battery 22 is configured as a rechargeable secondary battery such as a lithium ion battery or a nickel metal hydride battery.

  Boost converter 30 includes two gate type switching elements (for example, MOSFETs) Tr1 and Tr2 arranged in series so as to be parallel to smoothing capacitor 42 on the positive and negative buses of inverters 11 and 12, and each switching element Tr1, A known diode composed of two diodes D1 and D2 attached to hold a voltage in parallel with Tr2, and a coil 32 attached to the middle of the two switching elements Tr1 and Tr2 and the positive side of the battery 22. This is a boost converter. Relay 26 is attached between the positive output terminal of battery 22 and coil 32 of boost converter 30.

  The adjustment circuit 46 includes a diode D3 mounted in the forward direction between the positive output terminal of the battery 22 and the positive bus of the inverters 11 and 12, and a switching element Tr3 and a switching element Tr3 connected in parallel to the diode D3. And a resistor R3 connected in series with the diode D3.

  The electronic control unit 50 is configured as a microprocessor centered on the CPU 52. In addition to the CPU 52, a ROM 54 that stores processing programs, a RAM 56 that temporarily stores data, input / output ports and communication ports (not shown), and the like. Is provided. In the electronic control unit 50, the battery voltage Vb from the voltage sensor 24 attached between the output terminals of the battery 22, the capacitor voltage Vh from the voltage sensor 44 attached between the terminals of the smoothing capacitor 42, and the like pass through the input port. Have been entered. The electronic control unit 50 outputs a switching signal to the switching elements Tr1 and Tr2 of the boost capacitor 30, a switching signal to the switching element Tr3 of the adjustment circuit 46, a drive signal to the relay 26, and the like from the output port. . The electronic control unit 50 not only functions as a control unit for the power supply device 20, but also functions as a drive control unit for the two motors MG1 and MG2 for traveling. For this reason, the electronic control unit 50 is applied to the motor MG1 and MG2 from the rotational position of the rotor from the rotational position sensors 13 and 14 attached to the motors MG1 and MG2 and from a current sensor (not shown) attached to the inverters 11 and 12. The phase current to be input is input via the input port, and the switching signal to the inverters 11 and 12 is output from the electronic control unit 50 via the output port.

  The two motors MG1 and MG2 can be driven as generators and are configured as well-known synchronous generator motors that can be driven as motors, and are connected to the battery 22 via inverters 11 and 12 and a boost converter 30. Exchange power.

  The power supply device 20 thus configured basically has an electronic control unit so that the capacitor voltage Vh becomes the voltage command Vh * in order to smoothly exchange power between the battery 22 and the two motors MG1, MG2. 50, the switching elements Tr1 and Tr2 of the boost converter 30 are on / off controlled.

  Next, the operation of the diode D3 of the adjustment circuit 46 in the power supply device 20 of the embodiment will be described. When the power consumption of the motors MG1 and MG2 temporarily becomes excessive, the capacitor voltage Vh decreases due to the discharge from the smoothing capacitor. At this time, when the capacitor voltage Vh falls below the battery voltage Vb, a current flows from the battery 22 side to the smoothing capacitor 42 side via the diode D3. For this reason, the capacitor voltage Vh becomes the battery voltage Vb. Considering the case where the diode D3 is not provided as a comparative example, if the power consumption of the motors MG1 and MG2 temporarily becomes excessive, the capacitor voltage Vh will drop to a value of zero. Therefore, by providing the diode D3, an unexpected decrease in the capacitor voltage Vh can be suppressed to the battery voltage Vb.

  Next, the operation of the switching element Tr3 of the adjustment circuit 46 in the power supply device 20 according to the embodiment will be described. FIG. 2 is a flowchart showing an example of a switching control routine for turning on and off the switching element Tr3 of the adjustment circuit 46 executed by the electronic control unit 50. This routine is repeatedly executed every predetermined time (for example, every several msec). When the switching control routine is executed, the CPU 52 of the electronic control unit 50 firstly sets the voltage command Vh * set by the drive control routine (not shown) and the capacitor voltage Vh from the voltage sensor 44 to drive the motors MG1 and MG2. Is input (step S100), and the process of subtracting the capacitor voltage Vh from the input voltage command Vh * to calculate the voltage deviation ΔV is executed (step S110). Then, it is determined whether or not the voltage deviation ΔV is within the normal voltage range that is the range of the threshold value Vref with the value 0 interposed therebetween (step S120). When the voltage deviation ΔV is within the normal voltage range, this routine is terminated. When the voltage deviation ΔV falls below the normal voltage range, the switching element Tr3 is turned on to lower the capacitor voltage Vh (step S130), and this routine ends. When the voltage deviation ΔV exceeds the normal voltage range, the capacitor voltage Vh is reduced. In order to increase the switching element Tr3, the switching element Tr3 is turned off (step S140), and this routine is terminated. That is, when the capacitor voltage Vh becomes larger than the voltage command Vh * by the threshold value Vref, the switching element Tr3 is turned on to pass a current through the resistor R3 to the output terminal on the positive side of the battery 22 to lower the capacitor voltage Vh. When the voltage Vh becomes smaller than the voltage command Vh * by the threshold value Vref, the switching element Tr3 is turned off and current is prevented from flowing to the battery 22 side. In the embodiment, the threshold value Vref is set as a value smaller than the difference between the maximum voltage command Vh * set in the control and the withstand voltage of the smoothing capacitor 42. Thus, the capacitor voltage Vh is set to the voltage command Vh. * It is possible to suppress the threshold value Vref from being raised above the threshold value V, and to prevent the smoothing capacitor 42 from being damaged.

  FIG. 3 is a flowchart showing an example of a relay control routine for controlling on / off of the relay 26. This routine is repeatedly executed every predetermined time (for example, every several msec). When the relay control routine is executed, the CPU 52 of the electronic control unit 50 inputs an abnormality determination signal that is set to a value of 1 when an abnormality has occurred in the boost converter 30 by an abnormality determination routine (not shown) (step S200). Then, it is determined whether or not an abnormality has occurred in boost converter 30 based on the input abnormality determination signal (step S210). If no abnormality has occurred in boost converter 30, this routine is terminated as it is, and an abnormality has occurred in boost converter 30. If so, the relay 26 is turned off (step S220), and this routine ends. When relay 26 is turned off, boost converter 30 does not function. Thereby, boost converter 30 can be stopped only by turning off relay 26.

  According to the power supply device 20 of the embodiment described above, the diode D3 is attached in the forward direction between the positive buses of the inverters 11 and 12 and the positive output terminal of the battery 22 as viewed from the positive output terminal of the battery 22. Thus, an unexpected decrease in the capacitor voltage Vh that may occur when the power consumption of the motors MG1 and MG2 becomes temporarily excessive can be suppressed to the battery voltage Vb. As a result, it is possible to ensure the driving of the motors MG1 and MG2 without breaking the control of the motors MG1 and MG2.

  Further, according to the power supply device 20 of the embodiment, the switching element Tr3 is provided in parallel with the diode D3 and the resistor R3 is provided in series with the switching element Tr3, and when the capacitor voltage Vh becomes larger than the voltage command Vh * by the threshold value Vref, the switching element When Tr3 is turned on and the capacitor voltage Vh becomes smaller than the voltage command Vh * by the threshold value Vref, the switching element Tr3 is turned off to suppress the capacitor voltage Vh from becoming higher than the voltage command Vh * by the threshold value Vref or higher. In addition, the smoothing capacitor 42 can be prevented from being damaged.

  Furthermore, according to the power supply device 20 of the embodiment, the relay 26 is attached between the positive output terminal of the battery 22 and the coil 32 of the boost converter 30, and the relay 26 is turned off when an abnormality occurs in the boost converter 30. By doing so, it is possible to quickly cope with the abnormality of the boost converter 30.

  In the power supply device 20 of the embodiment, the resistor R3 is provided in series with the switching element Tr3. However, since it is sufficient if power can be consumed similarly to the resistor R3, as illustrated in the power supply device 20B of the modified example of FIG. The coil 32 of the boost converter 30 may be a coil 32B having an intermediate tap, and the switching element Tr3 may be connected to the intermediate tap of the coil 32B and the positive bus of the inverters 11 and 12.

  In the power supply device 20 of the embodiment, the switching element Tr3 is provided in parallel with the diode D3 and the resistor R3 is provided in series with the switching element Tr3. However, as illustrated in the power supply device 20C of the modified example of FIG. The element Tr3 and the resistor R3 may not be provided.

  In the power supply device 20 of the embodiment, the relay 26 is attached between the positive output terminal of the battery 22 and the coil 32 of the boost converter 30, but the intermediate point between the switching element Tr 1 and the switching element Tr 2 and the coil 32. It is good also as what attaches the relay 26 between. The relay 26 may not be provided.

  In the power supply device 20 of the embodiment, it has been described that it is connected to the two motors MG1 and MG2 via the inverters 11 and 12, but may be connected to one motor, and may be connected to three or more motors. It does not matter if it is done. Further, the connection destination is not limited to a motor or a generator, and any device that consumes power or any device that generates or regenerates power may be used.

  In the power supply device 20 of the embodiment, power is exchanged with the traveling motors MG1, MG2 mounted on the vehicle. However, power may be exchanged with other electrical devices without being mounted on the vehicle. .

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the manufacturing industry of a power supply device and a vehicle on which the power supply device is mounted.

It is a block diagram which shows the outline of a structure of the vehicle-mounted power supply device 20 as one Example of this invention. 3 is a flowchart showing an example of a switching control routine executed by an electronic control unit 50. 4 is a flowchart showing an example of a relay control routine executed by an electronic control unit 50. It is a block diagram which shows the outline of a structure of the power supply device 20B of a modification. It is a block diagram which shows the outline of a structure of the power supply device 20C of a modification.

Explanation of symbols

11, 12 Inverter, 13, 14 Rotation position sensor, 20, 20B, 20C Power supply device, 22 Battery, 24 Voltage sensor, 26 Relay, 30 Boost converter, 32 Coil, 42 Smoothing capacitor, 44 Voltage sensor, 46 Adjustment circuit, 50 Electronic control unit, 52 CPU, 54 ROM, 56 RAM, Tr1, Tr2, Tr3 switching element, D1, D2, D3 diode, R3 resistance, MG1, MG2 motor.

Claims (5)

A power supply device that exchanges power with electrical equipment,
DC power supply,
A boost converter capable of boosting the voltage of the DC power supply and supplying the boosted voltage to the electrical device;
A capacitor connected to a boost side terminal of the boost converter;
A bypass circuit configured to bypass the step-up converter from the DC power supply to the capacitor , the diode being connected in a forward direction with respect to the electrical device as viewed from the positive electrode of the DC power supply;
A switching element connected in parallel with the diode;
Voltage detecting means for detecting a voltage on the boost side of the boost converter;
The switching element is turned on when the detected voltage reaches a first voltage higher than a target voltage on the boost side set higher than the voltage of the DC power supply, and the detected voltage is applied to the DC power supply. Switch on / off means for turning off the switching element when a voltage lower than a second voltage higher than a voltage and lower than the target voltage is reached;
A power supply device comprising: The power supply device according to claim 1, further comprising a resistor connected in series to the diode. The power supply device according to claim 1 , wherein the diode is connected to an intermediate tap of a reactor included in the boost converter. 4. The power supply device according to claim 1 , wherein the step-up converter includes a relay that disables the step-up function while power can be supplied from the DC power source to the electric device. 5. An electric motor that outputs driving force for traveling;
The power supply device according to any one of claims 1 to 4 , wherein power is exchanged with the electric motor as the electric device.
A vehicle comprising:

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