JP2016046851A - Power supply - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply capable of reducing the state where power cannot be supplied to a power supplied part because of temperature characteristics of circuit elements or influences of individual differences.SOLUTION: In the case where a predetermined condition is satisfied after the lapse of a first preset time even if an inter-terminal voltage of a capacitor 15 does not become equal to or higher than a first voltage threshold until the first preset time elapses after a precharge relay 11 is turned on, in a power supply 3, an ECU 20 compares the inter-terminal voltage with the first voltage threshold until a second preset time further elapses. When the inter-terminal voltage becomes equal to or higher than the first voltage threshold, a main relay 12 is turned on and next, the precharge relay 11 is turned off. The predetermined condition indicates that, after the lapse of the first preset time, the inter-terminal voltage of the capacitor 15 is equal to or higher than a second voltage threshold which is smaller than the first voltage threshold.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power supply device that prevents an inrush current from flowing from a power supply unit to a power supply unit.

  A power supply device is provided between a power supply unit such as a commercial power supply and a power supply unit such as an electric load. The power supply device rectifies AC power by a rectifier circuit, and converts the rectified current into a capacitor. It is smoothed by.

  As a conventional power supply device of this type, a device in which a precharge relay is provided in parallel with a main relay and a resistor is connected in series to the precharge relay is known (see Patent Document 1).

  The power supply device described in Patent Document 1 turns on the precharge relay in advance and charges the capacitor with a current limited by the resistance, and then turns on the main relay to start supplying power to the electric load. The inrush current is prevented from flowing through the capacitor when the main relay is turned on.

  This power supply device determines that a failure has occurred in the power supply device when the voltage between the terminals of the capacitor does not exceed the determination voltage threshold before the predetermined time elapses after the precharge relay is turned on, and notifies the failure. The power supply to the load is not performed by turning on the main relay.

JP 2010-178413 A

  However, in the power supply device described in Patent Document 1, due to the temperature characteristics of the circuit elements and individual differences, even if the power supply device is not faulty, the voltage across the terminals of the capacitor is increased before a predetermined time elapses. The determination threshold voltage may not be exceeded.

  For this reason, the power supply device described in Patent Document 1 has a problem that it may be unable to supply power to the power supply unit due to the temperature characteristics of the circuit elements and individual differences.

  Therefore, an object of the present invention is to provide a power supply device that can reduce the state in which power cannot be supplied to the power supply unit due to the temperature characteristics of circuit elements and individual differences.

  A power supply device according to the present invention includes a capacitor provided in a power supply line between a power supply unit and a power supply unit, and a main unit provided between the power supply unit and the capacitor in the power supply line. A relay, a precharge relay provided to bypass the main relay between the power supply unit and the capacitor in the power supply line, and a resistor connected in series, and a voltage between terminals of the capacitor are detected. A voltage detection unit; and a relay control unit that controls the main relay and the precharge relay, and the relay control unit turns on the precharge relay until the first set time elapses. And the first voltage threshold, the main relay is turned on when the voltage between the terminals is equal to or higher than the first voltage threshold, In the power supply apparatus for turning off the precharge relay, the relay control unit is configured to perform the first operation even when the voltage between the terminals does not exceed the first voltage threshold before the first set time elapses. If the predetermined condition is satisfied when one set time elapses, a second set time comparison process for comparing the inter-terminal voltage and the first voltage threshold is executed until the second set time elapses, and the terminal When the inter-voltage becomes equal to or higher than the first voltage threshold, the main relay is turned on and then the precharge relay is turned off.

  According to the present invention, even if the voltage between the terminals of the capacitor does not exceed the first voltage threshold before the first set time elapses after the precharge relay is turned on, the predetermined condition is satisfied. In addition, when the voltage between the terminals becomes equal to or higher than the first voltage threshold before the second set time elapses, the main relay is turned on by the relay control unit.

  Thereby, possibility that electric power can be supplied to a to-be-powered supply part can be increased. Therefore, it is possible to reduce a situation in which power cannot be supplied to the power supply unit due to the influence of the temperature characteristics of the circuit elements and individual differences.

FIG. 1 is a block diagram of a charging system including a power supply device according to an embodiment of the present invention. FIG. 2 is a diagram showing a flowchart when the main relay and the precharge relay are controlled in the power supply device according to the embodiment of the present invention. FIG. 3 is a timing chart showing the terminal voltage of the capacitor and the determination result when the on-state of the precharge relay is extended in the power supply device according to the embodiment of the present invention. FIG. 4 is a time chart showing a voltage between terminals of the capacitor and a determination result when the precharge relay is once turned off and then turned on again in the power supply device according to the embodiment of the present invention. FIG. 5 is a diagram showing a change rate of the voltage between terminals of the capacitor and a determination result when the retry process is performed in the power supply device according to the embodiment of the present invention. FIG. 6 is a block diagram of a load system including a power supply device according to another embodiment of the present invention.

  Hereinafter, a power supply apparatus according to an embodiment of the present invention will be described with reference to FIGS.

  First, the configuration will be described. FIG. 1 is a block diagram of a charging system including a power supply device according to an embodiment of the present invention.

  As shown in FIG. 1, the charging system 1 includes a commercial power source 2, a power source device 3, and a high voltage storage battery 4, and AC power supplied from the commercial power source 2 as a power supply unit is It is rectified and smoothed by the power supply device 3 and converted into DC electricity, and the converted DC electricity is stored in the high-voltage storage battery 4 as the power supply section.

  The power supply device 3 includes power supply lines 9 and 10, a rectifier circuit 14, a capacitor 15, a voltage detection circuit 16, a charger circuit 17, a main relay 12, a precharge relay 11, and an ECU 20.

  The power supply lines 9 and 10 electrically connect the commercial power source 2 and the high voltage storage battery 4. Input terminals 5 and 6 are provided on the commercial power supply 2 side of the power supply lines 9 and 10, and AC electricity of the commercial power supply 2 is supplied to the power supply device 3 from the input terminals 5 and 6.

  Output terminals 7 and 8 are provided on the high-voltage storage battery 4 side of the power supply lines 9 and 10, and electricity converted into direct current by the power supply device 3 is supplied from the output terminals 7 and 8 to the high-voltage storage battery 4. .

  One of the power supply lines 9, 10 is a positive side line, and the other is a negative side line.

  The rectifier circuit 14 and the capacitor 15 are respectively connected in parallel to the power supply lines 9 and 10. The rectifier circuit 14 rectifies AC electricity supplied from the commercial power source 2. The capacitor 15 smoothes the electricity rectified by the rectifier circuit 14.

  The voltage detection circuit 16 is provided in parallel with the power supply lines 9 and 10, detects a voltage between terminals of the capacitor 15, and outputs a detection signal (voltage signal) to the ECU 20. The voltage detection circuit 16 constitutes a voltage detection unit in the present invention.

  The charger circuit 17 is provided in series with the power supply lines 9 and 10, and charges the high-voltage storage battery 4 with electricity rectified by the rectifier circuit 14 and smoothed by the capacitor 15. The charger circuit 17 is electrically connected to the ECU 20 and is driven by a charger drive signal from the ECU 20.

  The main relay 12 is provided between the commercial power supply 2 and the capacitor 15 in the power supply line 9. The precharge relay 11 is provided between the commercial power supply 2 and the capacitor 15 in the power supply line 9 so as to bypass the main relay 12. A resistor 13 is connected to the precharge relay 11 in series.

  The main relay 12 and the precharge relay 11 are electrically connected to the ECU 20 and are controlled to be turned on or off by the ECU 20. Here, in the main relay 12 and the precharge relay 11, “on” means a state in which the contact is closed and the power supply line 9 is conducted, and “off” means a state in which the contact is open and the power supply line 9 is shut off. .

  The ECU 20 is configured to include a microcomputer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an input / output interface, and the like.

  In the ECU 20, a program and various control constants are stored in advance in the ROM, and the CPU performs signal processing according to the program stored in advance in the ROM while using the temporary storage function of the RAM.

  The ECU 20 controls the main relay 12 and the precharge relay 11 to be turned on or off based on the voltage across the terminals of the capacitor 15 detected by the voltage detection circuit 16. Therefore, the ECU 20 includes a relay control unit 21.

  Next, the operation will be described. FIG. 2 is a flowchart when the ECU 20 controls the precharge relay 11 and the main relay 12.

  As shown in FIG. 2, first, the ECU 20 turns on the precharge relay 11 (step S1). As a result, the capacitor 15 passes through the resistor 13 provided in series with the precharge relay 11 and is charged with electricity whose current is limited. When charging of the capacitor 15 is started, the voltage between the terminals of the capacitor 15 gradually increases.

  Next, the ECU 20 compares the voltage between the terminals of the capacitor 15 detected by the voltage detection circuit 16 with the first voltage threshold until the first set time elapses after the precharge relay 11 is turned on. It is determined whether or not the voltage is equal to or higher than a first voltage threshold (step S2).

  When the voltage between the terminals is equal to or higher than the first voltage threshold in step S2, the ECU 20 turns on the main relay 12 (step S8). Here, the ECU 20 turns on the main relay 12 and supplies a charger drive signal to the charger circuit 17 to start charging the high-voltage storage battery 4.

  Next, the ECU 20 turns off the precharge relay 11 (step S7), and ends the process of this flowchart.

  When the voltage between the terminals of the capacitor 15 does not become the first voltage threshold or more until the first set time elapses in step S2, the ECU 20 determines whether or not a predetermined condition is satisfied (step S3). The predetermined condition in step S3 is a condition that the voltage across the capacitor 15 when the first set time has elapsed is equal to or greater than the second voltage threshold. The second voltage threshold is smaller than the first voltage threshold.

  The predetermined condition in step S3 may be a condition that the rate of change of the voltage between the terminals of the capacitor 15 when the first set time has elapsed is equal to or greater than the first voltage change rate threshold.

  When it is determined in step S3 that the predetermined condition is not satisfied, the ECU 20 determines that the power supply device 3 has failed, turns off the precharge relay 11 (step S7), and ends the process of this flowchart.

  In this case, the high voltage storage battery 4 is not charged. When it is determined in step S3 that the predetermined condition is not satisfied, the ECU 20 may notify that the power supply device 3 has failed.

  When it is determined in step S3 that the predetermined condition is satisfied, the ECU 20 performs a retry process (step S4). In this retry process, the ECU 20 determines to extend the ON state of the precharge relay 11.

  In the retry process, the ECU 20 may temporarily turn off the precharge relay 11 in addition to continuing the on state of the precharge relay 11.

  Next, the ECU 20 compares the inter-terminal voltage of the capacitor 15 with the first voltage threshold until the second set time elapses, and determines whether the inter-terminal voltage is equal to or higher than the first voltage threshold (step S5). ). Here, the start point of the second set time is the end point of the first set time. The process in step S5 corresponds to the second set time comparison process in the present invention. Hereinafter, the process of step S5 is also referred to as a second set time comparison process.

  When the inter-terminal voltage is equal to or higher than the first voltage threshold value in step S5, the ECU 20 proceeds to step S8. As a result, the main relay 12 is turned on.

  If the voltage between the terminals of the capacitor 15 does not exceed the first voltage threshold until the second set time elapses in step S5, the ECU 20 determines that the change rate of the voltage between the terminals when the second set time elapses is the second. It is determined whether or not the voltage change rate threshold value is exceeded (step S6).

  When the change rate of the voltage between the terminals is less than the second voltage change rate threshold value in step S6, the ECU 20 determines that the power supply device 3 has failed and turns off the precharge relay 11 (step S7). The process of the flowchart ends.

  When the change rate of the inter-terminal voltage is greater than or equal to the second voltage change rate threshold value in step S6, the ECU 20 returns the process to step S4. Thus, the ECU 20 compares the inter-terminal voltage and the first voltage threshold again in step S5 after step S4 until the second set time elapses.

  In the timing chart of FIG. 3, when the inter-terminal voltage changes in the form of the solid line Vc1, the inter-terminal voltage becomes equal to or higher than the first voltage threshold before the first set time elapses, and the power supply device 3 is operating normally. Therefore, the main relay 12 is turned on.

  In addition, when the voltage between the terminals has changed in the manner of the broken line Vc2, the voltage between the terminals did not become equal to or higher than the first voltage threshold before the first set time elapses. The on state of the precharge relay 11 is extended. Thereafter, since the voltage between the terminals is equal to or higher than the first voltage threshold before the second set time elapses, the main relay 12 is turned on.

  Further, when the inter-terminal voltage changes in the manner of the broken line Vc3, the inter-terminal voltage does not become the first voltage threshold or more and becomes the second voltage threshold or more before the first set time elapses. Absent. For this reason, it determines with the power supply device 3 being out of order, and the high voltage storage battery 4 is not charged.

  In the timing chart of FIG. 4, when the inter-terminal voltage changes in the form of the solid line Vc4, the inter-terminal voltage becomes equal to or higher than the first voltage threshold before the first set time elapses, and the power supply device 3 is operating normally. Therefore, the main relay 12 is turned on.

  Further, when the inter-terminal voltage changes in the manner of the broken line Vc5, the inter-terminal voltage does not become equal to or higher than the first voltage threshold before the first set time elapses but is equal to or higher than the second voltage threshold. Then, after the first set time has elapsed, the precharge relay 11 is once turned off and then turned on again. Thereafter, the main relay 12 is turned on because the voltage between the terminals is equal to or higher than the first voltage threshold before the second set time elapses.

  Further, when the inter-terminal voltage changes in the manner of the broken line Vc6, the inter-terminal voltage does not become equal to or higher than the first voltage threshold before the first set time elapses, and also exceeds the second voltage threshold. Absent. For this reason, it determines with the power supply device 3 being out of order, and the high voltage storage battery 4 is not charged.

  In step S6, as shown in FIG. 5, it is determined whether the power supply device 3 is operating normally or abnormally by comparing the rate of change of the voltage between the terminals and a predetermined value (second voltage change rate threshold). Is done.

  Next, the effect will be described. In the power supply device 3 according to the above-described embodiment, the ECU 20 performs the first set time even when the voltage between the terminals of the capacitor 15 does not exceed the first voltage threshold before the first set time elapses. If the predetermined condition is satisfied when the time elapses, the second set time comparison process (step S5) for comparing the voltage between the terminals and the first voltage threshold is further executed until the second set time elapses. When the voltage exceeds the first voltage threshold, the main relay 12 is turned on, and then the precharge relay 11 is turned off.

  As a result, even if the voltage between the terminals of the capacitor 15 does not exceed the first voltage threshold before the first set time elapses after the precharge relay 11 is turned on, the predetermined condition is satisfied. In addition, when the voltage between the terminals becomes equal to or higher than the first voltage threshold before the second set time elapses, the main relay is turned on by the ECU 20. Thereby, possibility that electric power can be supplied to the high voltage storage battery 4 can be increased.

  Therefore, it is possible to reduce the situation in which power cannot be supplied to the high-voltage storage battery 4 due to the temperature characteristics of the circuit elements and individual differences.

  Further, in the power supply device 3 according to the above embodiment, the predetermined condition is that the voltage between the terminals of the capacitor 15 when the first set time has elapsed is equal to or higher than the second voltage threshold value that is smaller than the first voltage threshold value. It is said.

  Thereby, when the voltage between the terminals of the capacitor 15 when the first set time has elapsed is equal to or higher than the second voltage threshold, the comparison between the terminal voltage and the first voltage threshold is further performed until the second set time elapses. Depending on the result, the main relay 12 may be turned on.

  For this reason, ECU20 can judge suitably the possibility that the voltage between the terminals of the capacitor | condenser 15 will become larger than a 1st voltage threshold value based on a 2nd voltage threshold value, when 1st setting time passes.

  In the power supply device 3 according to the above embodiment, the predetermined condition is that the rate of change of the voltage across the capacitor 15 when the first set time has elapsed is equal to or greater than the first voltage change rate threshold. Yes.

  Thereby, when the rate of change of the voltage between the terminals of the capacitor 15 when the first set time elapses is equal to or greater than the first voltage change rate threshold, the voltage between the terminal and the first voltage before the second set time elapses. The main relay 12 may be turned on according to the comparison result with the voltage threshold.

  For this reason, ECU20 can judge suitably the possibility that the voltage between the terminals of the capacitor | condenser 15 will become larger than a 1st voltage threshold value based on a 1st voltage change rate threshold value, when 1st setting time passes.

  Further, in the power supply device 3 according to the above-described embodiment, the ECU 20 compares the inter-terminal voltage of the capacitor 15 with the first voltage threshold until the second set time elapses. As a result, the inter-terminal voltage is the first voltage. Even when the voltage does not exceed the threshold, if the rate of change of the voltage between the terminals when the second set time elapses is equal to or greater than the second voltage change rate threshold, the second set time elapses further. The terminal voltage and the first voltage threshold are compared again. That is, the second set time comparison process in step S5 is executed again. Then, the ECU 20 turns on the main relay 12 and then turns off the precharge relay 11 when the inter-terminal voltage becomes equal to or higher than the first voltage threshold.

  Thereby, even if the voltage between the terminals of the capacitor 15 does not exceed the first voltage threshold before the second set time elapses, the rate of change in the voltage between the terminals when the second set time elapses. Is greater than or equal to the second voltage change rate threshold, the main relay 12 can be turned on according to the result of comparing the terminal voltage and the first voltage threshold again until the second set time elapses. There is sex.

  For this reason, ECU20 can judge suitably the possibility that the voltage between the terminals of the capacitor | condenser 15 will become larger than a 1st voltage threshold value based on a 2nd voltage change rate threshold value.

  In the power supply device 3 according to the above-described embodiment, the ECU 20 turns off the precharge relay 11 once and turns it on again as a retry process in step S4 immediately before the second set time comparison process in step S5. .

  As a result, even when the increase in the voltage across the terminals of the capacitor 15 is hindered due to poor contact of the precharge relay 11, the ECU 20 temporarily turns off the precharge relay 11 and turns it on again. The contact failure of the relay 11 can be eliminated.

  As described above, the embodiments of the present invention have been described, but it is obvious that those skilled in the art can make changes, modifications, and alterations without departing from the scope of the present invention. Such alterations, modifications, and variations and equivalents are intended to be included within the scope of the claims.

  The present invention can also be applied to the power supply device 33 provided in the load system 30 shown in FIG. In FIG. 6, the load system 30 includes a DC power supply 31 as a power supply unit, a power supply device 33, and a load 32 as a power supplied unit, and the power supply device 33 converts the direct current supplied from the DC power supply 31 into an inverter. It is converted into alternating current by 34 and supplied to the load 32.

  The power supply device 33 includes a precharge relay 11, a main relay 12, a capacitor 15, and a voltage detection circuit 16, similarly to the power supply device 3 of FIG. 1. The ECU 35 of the power supply device 33 includes the relay control unit 21 as in the power supply device 3 of FIG. The ECU 35 of the power supply device 33 controls the precharge relay 11 and the main relay 12 in the same manner as the ECU 20 of the power supply device 3 in FIG.

2 Commercial power supply (power supply unit)
3 Power supply device 4 High voltage storage battery (power supply unit)
9 Power supply line 11 Precharge relay 12 Main relay 13 Resistor 15 Capacitor 16 Voltage detection circuit (voltage detection unit)
21 Relay control unit

Claims (5)

A capacitor provided in a power supply line between the power supply unit and the power supply unit;
A main relay provided between the power supply unit and the capacitor in the power supply line;
A precharge relay provided to bypass the main relay between the power supply unit and the capacitor in the power supply line, and a resistor connected in series;
A voltage detection unit for detecting a voltage between terminals of the capacitor;
A relay control unit that controls the main relay and the precharge relay;
The relay control unit
The terminal voltage is compared with the first voltage threshold until the first set time elapses after the precharge relay is turned on, and the main relay is turned on when the terminal voltage exceeds the first voltage threshold. And then turning off the precharge relay,
The relay control unit
Even when the voltage between the terminals does not become the first voltage threshold or more before the first set time elapses, when a predetermined condition is satisfied when the first set time elapses,
Further, a second set time comparison process for comparing the inter-terminal voltage and the first voltage threshold is performed until a second set time elapses, and when the inter-terminal voltage becomes equal to or higher than the first voltage threshold, the main A power supply device characterized by turning on a relay and then turning off a precharge relay.   2. The power supply device according to claim 1, wherein the predetermined condition is that the voltage between the terminals when the first set time elapses is equal to or higher than a second voltage threshold value smaller than the first voltage threshold value.   2. The power supply device according to claim 1, wherein the predetermined condition is that a change rate of the inter-terminal voltage when the first set time elapses is equal to or greater than a first voltage change rate threshold value. The relay control unit
In the second set time comparison process, even when the voltage between the terminals does not become the first voltage threshold value or more,
When the change rate of the voltage between the terminals when the second set time has elapsed is equal to or greater than a second voltage change rate threshold,
The second set time comparison process is executed again, and when the inter-terminal voltage becomes equal to or higher than the first voltage threshold, the main relay is turned on and then the precharge relay is turned off. The power supply device according to any one of claims 1 to 3. The relay control unit
5. The power supply device according to claim 1, wherein the precharge relay is temporarily turned off and turned on again immediately before the second set time comparison process. 6.

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