Voltage detection device

Patent metadata

Field	Value
Publication number	US-10031190-B2
Application number	US-201414264195-A
Country	US
Kind code	B2
Filing date	Apr 29, 2014
Priority date	May 6, 2013
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A voltage detection device controls operation of system main relays to change an applied voltage supplied to detection circuits. An error of each of the detection circuits is corrected on the basis of a detection value of each of the detection circuits when the applied voltage is changed. In particular, an offset value is corrected on the basis of a detection value of each of the detection circuits when the system main relays and booster switches are controlled so that a voltage of a high voltage battery supplied to each of the detection circuits becomes zero. A gain error is further corrected on the basis of a detection value of each of the detection circuits when the system main relays and the booster switches are controlled so that the applied voltage supplied to each of the detection circuits becomes equal to the voltage of the high voltage battery.

First claim

What is claimed is:

1. A voltage detection device to be applied to an inverter device capable of converting a direct current power of a direct current power source to an alternating current power,
the voltage detection device comprising:
a pair of a first connection line and a second connection line connected to both end terminals of the direct current power source;
an input voltage detection circuit connected between the first connection line and the second connection line, configured to detect a supplied direct current voltage which is supplied from the direct current power source to the inverter device;
a reference voltage detection circuit connected between the first connection line and the second connection line to detect, as a reference voltage, a voltage potential between the first connection line and the second connection line, the reference voltage detection circuit having a detection accuracy higher than a detection accuracy of the input voltage detection circuit;
a voltage change circuit comprising a booster circuit and an inverter circuit configured to adjust the supplied direct current voltage detected by the input voltage detection circuit, the booster circuit comprising a first booster switch and a second booster switch connected in series, the first booster switch being connected to the first connection line, the second booster switch being connected to the second connection line, and the booster circuit boosting the supplied direct current voltage supplied from the direct current power source, the inverter circuit converting the voltage boosted by the booster circuit to an alternating current voltage;
a computer system, comprising a central processing unit and memory for storing instructions which upon execution by the central processing unit enable the computer system to at least provide:
a voltage control section configured to generate a voltage control signal to control a voltage value changing operation of the voltage change circuit, and to transmit the voltage control signal to the voltage change circuit; and
an error correction section configured to calculate a voltage difference between the supplied direct current voltage detected by the input voltage detection circuit and a predetermined voltage, to generate a correction signal on the basis of the voltage difference calculated by the error correction section, and to transmit the correction signal to the voltage control section so that the supplied direct current voltage becomes equal to the predetermined voltage,
wherein the input voltage detection circuit comprises a low voltage detection circuit configured to detect a voltage at a low voltage side of the booster circuit,
the reference voltage detection circuit comprises a high voltage detection circuit configured to detect a voltage boosted by the booster circuit at a high voltage side of the booster circuit, and
the error correction section corrects the gain error of the input voltage detection circuit on the basis of the supplied direct current voltage detected by the input voltage detection circuit and the reference voltage detected by the reference voltage detection circuit when the voltage control section controls the operation of the voltage change circuit so that a voltage at the high voltage side of the booster circuit and a voltage at the low voltage side of the booster circuit become equal to the supplied direct current voltage supplied from the direct current power source at a timing when the first booster switch in the booster circuit is turned on and the second booster switch is turned off.

2. The voltage detection device according to claim 1 , wherein the inverter device comprises the booster circuit configured to boost the supplied direct current voltage supplied from the direct current power source and the inverter circuit configured to convert the voltage boosted by the booster circuit to an alternating current voltage,
the reference voltage detection circuit comprises a power source voltage detection circuit configured to detect the power source voltage of the direct current power source, and
the error correction section corrects the gain error of the input voltage detection circuit on the basis of
the supplied direct current voltage detected by the input voltage detection circuit and the reference voltage detected by the reference voltage detection circuit when the voltage control section controls the operation of the voltage change circuit so that the supplied direct current voltage becomes equal to the power source voltage of the direct current power source to be supplied to the reference voltage detection circuit.

3. The voltage detection device according to claim 2 , wherein the error correction section prohibits the correction of the gain error when the reference voltage detected by the reference voltage detection circuit is not more than a predetermined judgment threshold value.

4. The voltage detection device according to claim 1 , wherein the first connection line is connected to a high voltage side of the direct current power source and the second connection line is connected to a low voltage side of the direct current power source,
the first booster switch and the second booster switch form a series connection unit connected in series in the booster circuit, the first booster switch is connected to the first connection line and the second booster switch is connected to the second connection line,
the inverter circuit comprises series connection units, each of the series connection units in the inverter circuit comprises a first conversion switch and a second conversion switch connected in series, the first conversion switch is connected to the first connection line, and the second conversion switch is connected to the second connection line, and
the voltage change circuit comprises at least one of the series connection unit comprised of the first booster switch and the second booster switch and the series connection units comprised of the first conversion switch and the second conversion switch.

5. The voltage detection device according to claim 1 , wherein the error correction section performs, as an abnormality process, one of prohibition from correcting the gain error and a warning of an abnormality state supplied to an operator when the supplied direct current voltage detected by the input voltage detection circuit and the reference voltage detected by the reference voltage detection circuit become out from a predetermined allowable range at a timing when the voltage control section performs a control of the voltage change circuit so that the supplied direct current voltage and the voltage supplied to the reference voltage detection circuit become equal to the power source voltage of the direct current power source.

6. The voltage detection device according to claim 1 , wherein the voltage change circuit comprises a switching section capable of electrically connecting and disconnecting an electrical connection between the direct current power source and the inverter device, and
the error correction section corrects an offset error of the input voltage detection circuit on the basis of the supplied direct current voltage detected by the input voltage detection circuit when the voltage control section turns off at least the switching section so that the supplied direct current voltage becomes zero.

7. The voltage detection device according to claim 6 , wherein the error correction section prohibits the correction of the offset error when the supplied direct current voltage detected by the input voltage detection section is more than a predetermined threshold value when the voltage control section turns off the switching section.

Assignees

• Denso Corp

Inventors

• Nakamura Syota
• Fukuta Junichi

Classifications

• G01R31/42 Primary

  AC power supplies · CPC title

• G01R19/0084

  Measuring voltage only · CPC title