JP5769780B2 - Switching power supply device and power supply method - Google Patents

Description

  The present invention relates to a switching power supply device and a power supply method that are mounted on a vehicle, for example, and step down a high voltage of a high voltage battery to a low voltage to charge the low voltage battery.

  2. Description of the Related Art Conventionally, for example, an insulated DC-DC converter device that converts a voltage level of DC power is known as a vehicle-mounted insulated switching power supply device mounted on an electric vehicle or a hybrid car. This insulated DC-DC converter device steps down a high voltage supplied from a high voltage battery typified by a lithium ion battery to a low voltage that is a power supply voltage of an auxiliary electrical component while maintaining insulation.

  Here, in such an insulation type DC-DC converter device, an insulation type control power supply circuit that steps down the high voltage of the high voltage battery to a low voltage is used to supply the power supply voltage to the control unit inside the DC-DC converter. In addition, it is known to use a control power supply circuit that steps up and down a low voltage of an auxiliary battery (hereinafter also referred to as “low voltage battery”).

  In addition, a DC-DC converter that converts a high voltage of the high voltage battery into a low voltage and a voltage dividing circuit for extracting the low voltage from the high voltage battery are provided, and the low voltage extracted from the voltage dividing circuit is controlled by the DC-DC converter. A power supply control device is proposed in which the DC-DC converter can be started by supplying to the unit, and the output of the DC-DC converter and the control unit of the DC-DC converter are connected after the completion of the startup of the DC-DC converter. (For example, refer to Patent Document 1).

Japanese Patent No. 4622642

However, the prior art has the following problems.
That is, the isolated control power supply circuit that steps down the high voltage of the high-voltage battery to a low voltage is effective against noise (EMC: Electromagnetic Compatibility), but compared to the control power supply circuit that steps up and down the low voltage of the auxiliary battery. High cost. On the other hand, the control power supply circuit is less expensive than the insulated control power supply circuit, but it is difficult to take measures against noise.

  In order for the control unit of the DC-DC converter to communicate the DC-DC converter state and the self-failure diagnosis result, such as the temperature of the DC-DC converter and the voltage value of the high-voltage / low-voltage battery line, to the host or other microcomputer. However, it is necessary to connect both the insulated control power supply circuit and the control power supply circuit to the control unit of the DC-DC converter, which is very expensive and disadvantageous in terms of noise and board occupation.

  In addition, the high-voltage battery line connected to the DC-DC converter including the power supply control device of Patent Document 1 is disconnected due to an accident, malfunction, repair, etc., or the contactor is turned off. When a disconnection or the like occurs, there is a problem that the control unit of the DC-DC converter may not be able to communicate the state of the DC-DC converter and the self-failure diagnosis result to the host or another microcomputer.

  The present invention has been made to solve the above-described problems, and can reliably communicate the state of the DC-DC converter and the self-failure diagnosis result to a host or another microcomputer at a low cost. An object of the present invention is to obtain a switching power supply device and a power supply method.

A switching power supply according to the present invention is a switching power supply that steps down a high voltage of a high voltage battery to a low voltage and charges the low voltage battery, a switching unit that converts a DC voltage from the high voltage battery into an AC voltage, A control circuit that controls the operation of the drive circuit, and that can communicate with the outside, and a control power supply circuit unit that supplies a power supply voltage to the drive circuit and the controller. The first low voltage generation circuit that transforms the power supply voltage supplied to the drive circuit to a low voltage that is the power supply voltage of the controller and supplies the low voltage from the low-voltage battery to the controller power supply and a second low-voltage generating circuit to the control unit and transformer to a low voltage which is a voltage, and a high voltage from the high voltage battery, a transformer to drive rotating at a low voltage is a supply voltage of the driving circuit And supplies to and supplies at least one of the low voltage from the high voltage and the low voltage battery from the high-voltage battery, the controller then transformed to a low voltage is a supply voltage of the controller.

A power supply method according to the present invention includes a switching unit that converts a DC voltage from a high-voltage battery into an AC voltage, a drive circuit that drives the switching unit, and a controller that controls the operation of the drive circuit and can communicate with the outside. And a control power supply circuit section that supplies a power supply voltage to the drive circuit and the controller, and the control power supply circuit section transforms the power supply voltage supplied to the drive circuit to a low voltage that is the power supply voltage of the controller. And a second low voltage generation circuit that transforms the low voltage from the low-voltage battery into a low voltage that is a power supply voltage of the controller and supplies the low voltage to the controller. and, a power supply method performed by a switching power supply for charging the low voltage battery by stepping down the high voltage of the high voltage battery to a low voltage, the high voltage from the high voltage battery, a low voltage is a supply voltage of the driving circuit Transforming and supplying to the drive circuit; transforming at least one of a high voltage from the high voltage battery and a low voltage from the low voltage battery to a low voltage which is a power supply voltage of the controller; It is what has.

According to the switching power supply device according to the present invention, the control power supply circuit unit transforms the high voltage from the high voltage battery into the low voltage that is the power supply voltage of the drive circuit and supplies it to the drive circuit, and the high voltage from the high voltage battery. At least one of the voltage and the low voltage from the low-voltage battery is transformed into a low voltage that is a power supply voltage of the controller and supplied to the controller.
According to the power supply method of the present invention, the step of transforming the high voltage from the high voltage battery to the low voltage, which is the power supply voltage of the drive circuit, and supplying it to the drive circuit, the high voltage and low voltage from the high voltage battery, Transforming at least one of the low voltages from the battery to a low voltage, which is a power supply voltage of the controller, and supplying it to the controller.
Therefore, it is possible to obtain a switching power supply device and a power supply method that can reliably communicate the state of the DC-DC converter and the self-failure diagnosis result to the host or another microcomputer at low cost.

It is a block diagram which shows the switching power supply device concerning Embodiment 1 of this invention with a battery. It is a block diagram which shows the switching power supply apparatus which concerns on Embodiment 2 of this invention with a battery. It is a block diagram which shows the switching power supply apparatus which concerns on Embodiment 3 of this invention with a battery.

  Hereinafter, preferred embodiments of a switching power supply device and a power supply method according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.

Embodiment 1 FIG.
1 is a configuration diagram showing a switching power supply device according to Embodiment 1 of the present invention together with a battery. In FIG. 1, an insulation type DC-DC converter 1 which is a switching power supply device is connected between a high voltage battery 2 and an auxiliary battery 3. The DC-DC converter 1 steps down the high voltage of the high-voltage battery 2 to a low voltage that is a power supply voltage of auxiliary equipment electrical equipment (not shown) and charges the auxiliary battery 3.

  The DC-DC converter 1 includes an input filter unit 11, for example, a switching unit 12 constituted by a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), a transformer unit 13, and a rectifying / smoothing unit 14.

  Here, the DC-DC converter 1 inputs a high voltage from the high-voltage battery 2 to the switching unit 12 via the input filter unit 11, converts it to an AC voltage by the switching unit 12, and then transforms it by the transformer unit 13. Further, the rectifying and smoothing unit 14 rectifies and smoothes and outputs a DC low voltage.

  The DC-DC converter 1 includes a DC-DC converter drive circuit 15 that generates a switching waveform of the switching unit 12, a controller 16 that controls the operation of the DC-DC converter 1, and the DC-DC converter drive circuit 15 and the controller 16. And a control power supply circuit section 20 for supplying a power supply voltage necessary for the operation.

  The controller 16 is composed of a microcomputer, a control IC, and the like, and controls the operation of the DC-DC converter drive circuit 15, and also the DC-DC converter, such as the temperature of the DC-DC converter 1 and the voltage value of the high-voltage / low-voltage battery line. The state of 1 and the self-failure diagnosis result are communicated to the host and other microcomputers.

  The control power supply circuit unit 20 includes a control power supply drive circuit 21, a control power supply transformation unit 22, a control power supply rectification smoothing unit 23, a first low voltage generation circuit 24, a first diode 25, a second low voltage generation circuit 26, and a second diode. 27 and a smoothing capacitor 28.

  The control power supply circuit unit 20 converts the high voltage from the high voltage battery 2 into an AC voltage by the control power supply drive circuit 21 and transforms it to a low voltage that is the power supply voltage of the DC-DC converter drive circuit 15 by the control power supply transformer unit 22. After that, the control power supply rectifying / smoothing unit 23 rectifies and smoothes the power supply voltage to the DC-DC converter drive circuit 15.

  The first low voltage generation circuit 24 steps down the voltage supplied to the DC-DC converter drive circuit 15 to generate a low voltage that is a power supply voltage of the controller 16, and supplies the generated low voltage to the controller 16. To do. The first diode 25 prevents a current from flowing back to the first low voltage generation circuit 24.

  The second low voltage generation circuit 26 steps down the low voltage from the auxiliary battery 3 to generate a low voltage that is a power supply voltage of the controller 16, and supplies the generated low voltage to the controller 16. The second diode 27 prevents the current from flowing back to the second low voltage generation circuit 26. The smoothing capacitor 28 smoothes the low voltage from the first low voltage generation circuit 24 and the second low voltage generation circuit 26.

  Here, the low voltage generated by the first low voltage generation circuit 24 and the low voltage generated by the second low voltage generation circuit 26 have the same potential or have a gradient so that a high voltage is obtained. Even when the voltage of the battery 2 or the auxiliary battery 3 is lowered or opened, the power supply voltage of the controller 16 is supplied from any battery.

  That is, even when the high voltage value deviates from the normal range due to a contactor or other unit malfunction or repair of the high voltage battery 2 or when the voltage drop of the auxiliary battery 3 is significant, the high voltage battery 2 and the auxiliary battery As long as at least one of the terminals 3 is connected, the power supply voltage is supplied to the controller 16 and the controller 16 operates.

  Thereby, the controller 16 can communicate the state of the DC-DC converter 1 and the self-failure diagnosis result, such as the temperature of the DC-DC converter 1 and the voltage value of the high-voltage / low-voltage battery line, to the host computer and other microcomputers. The DC-DC converter 1 can sufficiently improve safety and reliability.

  In addition, unlike the conventional technology, both the isolated control power supply circuit that steps down the high voltage of the high voltage battery to the low voltage and the control power supply circuit that steps up and down the low voltage of the auxiliary battery are prepared from the auxiliary battery. By reducing the capacity of the control power supply circuit, the cost can be reduced and the size can be reduced.

As described above, according to the first embodiment, the control power supply circuit unit transforms the high voltage from the high voltage battery into the low voltage that is the power supply voltage of the drive circuit and supplies the transformed voltage to the drive circuit. At least one of the high voltage and the low voltage from the low voltage battery is transformed into a low voltage which is a power supply voltage of the controller and supplied to the controller.
The control power supply circuit unit transforms the power supply voltage supplied to the drive circuit into a low voltage that is the power supply voltage of the controller and supplies the low voltage from the low voltage battery. And a second low voltage generation circuit that transforms the power to a low voltage that is a power supply voltage of the controller and supplies the voltage to the controller.
Therefore, it is possible to obtain a switching power supply device and a power supply method that can reliably communicate the state of the DC-DC converter and the self-failure diagnosis result to the host or another microcomputer at low cost.

Embodiment 2. FIG.
FIG. 2 is a block diagram showing a switching power supply device according to Embodiment 2 of the present invention together with a battery. In FIG. 2, the control power supply circuit unit 20 </ b> A of the DC-DC converter 1 </ b> A further includes a determination circuit 29 that determines the voltage value of the power supply voltage supplied to the DC-DC converter drive circuit 15. Other configurations are the same as those shown in FIG.

  The determination circuit 29 operates the first low voltage generation circuit 24 when the voltage value of the power supply voltage supplied to the DC-DC converter drive circuit 15 is larger than a predetermined set voltage value, The low voltage generation circuit 26 is not operated.

  The determination circuit 29 stops the operation of the first low voltage generation circuit 24 when the voltage value of the power supply voltage supplied to the DC-DC converter drive circuit 15 is equal to or lower than the set voltage value. The second low voltage generation circuit 26 is operated. Thereby, supply of the power supply voltage to the controller 16 can be continued.

  In addition, the determination circuit 29 has a second low voltage when the voltage value of the power supply voltage supplied to the DC-DC converter drive circuit 15 is larger than the set voltage value (that is, when the voltage value returns to the normal range). The operation of the voltage generation circuit 26 is stopped and the first low voltage generation circuit 24 is operated.

  As a result, as long as at least one of the high voltage battery 2 and the auxiliary battery 3 is connected, the power supply voltage is supplied to the controller 16, and the controller 16 determines the temperature of the DC-DC converter 1 and the high voltage / low voltage battery line. The state of the DC-DC converter 1 and the self-failure diagnosis result, such as the voltage value of, can be communicated to the host and other microcomputers, and the DC-DC converter 1 can sufficiently improve safety and reliability. .

  In addition, unlike the conventional technology, both the isolated control power supply circuit that steps down the high voltage of the high voltage battery to the low voltage and the control power supply circuit that steps up and down the low voltage of the auxiliary battery are prepared from the auxiliary battery. By reducing the capacity of the control power supply circuit, the cost can be reduced and the size can be reduced.

As described above, according to the second embodiment, the control power supply circuit unit further includes a determination circuit that determines the voltage value of the power supply voltage supplied to the drive circuit, and the determination circuit is supplied to the drive circuit. When the voltage value of the power supply voltage is equal to or lower than a predetermined set voltage value, the operation of the first low voltage generation circuit is stopped and the second low voltage generation circuit is operated to be supplied to the drive circuit. When the voltage value of the power supply voltage to be larger than the set voltage value, the operation of the second low voltage generation circuit is stopped and the first low voltage generation circuit is operated.
Therefore, it is possible to obtain a switching power supply device and a power supply method that can reliably communicate the state of the DC-DC converter and the self-failure diagnosis result to the host or another microcomputer at low cost.
Further, power consumption and noise can be reduced by operating only one of the first low voltage generation circuit and the second low voltage generation circuit at the same time.

Embodiment 3 FIG.
FIG. 3 is a configuration diagram showing a switching power supply device according to Embodiment 3 of the present invention together with a battery. In FIG. 3, the control power supply circuit unit 20B of the DC-DC converter 1B has a first low voltage generation circuit 24B instead of the first low voltage generation circuit 24 and the second low voltage generation circuit 26 shown in FIG. doing. Other configurations are the same as those shown in FIG.

  In the control power supply circuit unit 20 </ b> B, the low voltage from the auxiliary battery 3 is supplied to the line through which the power supply voltage is supplied to the DC-DC converter drive circuit 15 via the second diode 27. That is, the low voltage generated by insulation from the high voltage battery 2 and the low voltage from the auxiliary battery 3 are supplied to the first low voltage generation circuit 24B.

  Here, the first low voltage generation circuit 24B normally generates a low voltage that is a power supply voltage of the controller 16 by stepping down the voltage supplied to the DC-DC converter drive circuit 15, and supplies the controller 16 with the low voltage. Supply.

  Further, the first low voltage generation circuit 24B is configured such that when the output voltage of the first low voltage generation circuit 24B decreases (for example, the voltage value of the power supply voltage supplied to the DC-DC converter drive circuit 15 is equal to or less than the set voltage value). ), The low voltage from the auxiliary battery 3 is stepped down to generate a low voltage that is the power supply voltage of the controller 16 and supplied to the controller 16.

  As a result, as long as at least one of the high voltage battery 2 and the auxiliary battery 3 is connected, the power supply voltage is supplied to the controller 16, and the controller 16 determines the temperature of the DC-DC converter 1 and the high voltage / low voltage battery line. The state of the DC-DC converter 1 and the self-failure diagnosis result, such as the voltage value of, can be communicated to the host and other microcomputers, and the DC-DC converter 1 can sufficiently improve safety and reliability. .

As described above, according to the third embodiment, the control power supply circuit unit transforms and controls the power supply voltage supplied to the drive circuit and the low voltage from the low-voltage battery to the low voltage that is the power supply voltage of the controller. A first low voltage generation circuit for supplying to the device.
Therefore, it is possible to obtain a switching power supply device and a power supply method that can reliably communicate the state of the DC-DC converter and the self-failure diagnosis result to the host or another microcomputer at low cost.
Further, by supplying the power supply voltage to the controller 16 only by the first low voltage generation circuit 24B, the second low voltage generation circuit 26 shown in FIGS. 1 and 2 can be made unnecessary and the cost can be reduced. Can do.

  In the first to third embodiments, the configuration in which the control power supply circuit unit is provided inside the DC-DC converter is shown, but the present invention is not limited to this. The control power supply circuit unit is not mounted on the DC-DC converter and can supply power supply voltage from other units.

  In the first to third embodiments, the control power supply circuit unit is applied to a DC-DC converter. However, the present invention is not limited to this. The control power supply circuit unit can also be applied to an inverter, a boost converter, and the like.

  1, 1A, 1B converter, 2 high voltage battery, 3 auxiliary battery, 11 input filter unit, 12 switching unit, 13 transformer unit, 14 rectifying smoothing unit, 15 DC-DC converter drive circuit, 16 controller, 20, 20A, 20B control power supply circuit section, 21 control power supply drive circuit, 22 control power supply transformer section, 23 control power supply rectification smoothing section, 24, 24B first low voltage generation circuit, 25 first diode, 26 second low voltage generation circuit, 27 first 2 diodes, 28 smoothing capacitors, 29 judgment circuit.

Claims (5)

A switching power supply that steps down a high voltage of a high voltage battery to a low voltage and charges the low voltage battery,
A switching unit that converts a DC voltage from the high-voltage battery into an AC voltage;
A drive circuit for driving the switching unit;
A controller for controlling the operation of the drive circuit and capable of communicating with the outside;
A control power supply circuit section for supplying a power supply voltage to the drive circuit and the controller,
The control power circuit section is
A first low voltage generation circuit that transforms a power supply voltage supplied to the drive circuit to a low voltage that is a power supply voltage of the controller and supplies the voltage to the controller;
A second low voltage generation circuit that transforms a low voltage from the low voltage battery into a low voltage that is a power supply voltage of the controller and supplies the low voltage to the controller;
The high voltage from the high voltage battery is transformed to a low voltage that is a power supply voltage of the drive circuit and supplied to the drive circuit, and at least one of the high voltage from the high voltage battery and the low voltage from the low voltage battery is supplied. A switching power supply that transforms the controller to a low voltage that is a power supply voltage of the controller and supplies the transformed voltage to the controller. The control power supply circuit unit further includes a determination circuit that determines a voltage value of a power supply voltage supplied to the drive circuit,
The determination circuit includes:
When the voltage value of the power supply voltage supplied to the drive circuit becomes equal to or lower than a predetermined set voltage value, the operation of the first low voltage generation circuit is stopped and the second low voltage generation circuit Operate
When the voltage value of the power supply voltage supplied to the drive circuit becomes larger than the set voltage value, the operation of the second low voltage generation circuit is stopped and the first low voltage generation circuit is operated. The switching power supply device according to claim 1 . A switching power supply that steps down a high voltage of a high voltage battery to a low voltage and charges the low voltage battery,
A switching unit that converts a DC voltage from the high-voltage battery into an AC voltage;
A drive circuit for driving the switching unit;
A controller for controlling the operation of the drive circuit and capable of communicating with the outside;
A control power supply circuit section for supplying a power supply voltage to the drive circuit and the controller,
The control power circuit section is
A first low voltage generation circuit that transforms a power supply voltage supplied to the drive circuit and a low voltage from the low-voltage battery into a low voltage that is a power supply voltage of the controller and supplies the low voltage to the controller;
The high voltage from the high voltage battery is transformed to a low voltage that is a power supply voltage of the drive circuit and supplied to the drive circuit, and at least one of the high voltage from the high voltage battery and the low voltage from the low voltage battery is supplied. A switching power supply that transforms the controller to a low voltage that is a power supply voltage of the controller and supplies the transformed voltage to the controller. A switching unit that converts a DC voltage from the high-voltage battery into an AC voltage, a drive circuit that drives the switching unit, a controller that controls the operation of the drive circuit, and that can communicate with the outside, the drive circuit, and the drive circuit A control power supply circuit section for supplying a power supply voltage to the controller, and the control power supply circuit section transforms the power supply voltage supplied to the drive circuit to a low voltage that is the power supply voltage of the controller. A first low voltage generation circuit that supplies the controller; and a second low voltage generation circuit that transforms the low voltage from the low-voltage battery into a low voltage that is a power supply voltage of the controller and supplies the low voltage to the controller. has a high voltage of the high voltage battery to a power supply method performed by a switching power supply device steps down to a low voltage to charge the low voltage battery,
Transforming a high voltage from the high voltage battery to a low voltage which is a power supply voltage of the drive circuit and supplying the transformed voltage to the drive circuit;
Transforming at least one of a high voltage from the high-voltage battery and a low voltage from the low-voltage battery into a low voltage that is a power supply voltage of the controller, and supplying the transformed voltage to the controller;
A power supply method. A switching unit that converts a DC voltage from the high-voltage battery into an AC voltage, a drive circuit that drives the switching unit, a controller that controls the operation of the drive circuit, and that can communicate with the outside, the drive circuit, and the drive circuit A control power supply circuit section for supplying a power supply voltage to the controller , wherein the control power supply circuit section supplies the power supply voltage supplied to the drive circuit and the low voltage from the low-voltage battery to the power supply voltage of the controller. and a transformer to a low voltage having a first low voltage generation circuit for supplying to the controller, the power supply that is performed by the switching power supply unit for charging the high voltage of the high voltage battery to the low voltage battery steps down to a low voltage A method,
Transforming a high voltage from the high voltage battery to a low voltage which is a power supply voltage of the drive circuit and supplying the transformed voltage to the drive circuit;
Transforming at least one of a high voltage from the high-voltage battery and a low voltage from the low-voltage battery into a low voltage that is a power supply voltage of the controller, and supplying the transformed voltage to the controller;
A power supply method.

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