Voltage conversion system and method and recording medium

• US 6,775,115 B2
• Filed: 12/13/2002
• Issued: 08/10/2004
• Est. Priority Date: 12/20/2001
• Status: Expired due to Term

• Current Assignee: DENSO Corporation
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Sato, Eiji
• Primary Examiner(s): Riley, Shawn
• Application Number:
  US10/318,226
• Publication Number:
  US 20030117823A1
• Time in Patent Office: 606 Days
• Field of Search: 307/10.7, 307/134, 307/125, 307/10.1, 361/18, 361/23, 363/56.02, 318/139, 318/141, 318/767, 180/2.1
• US Class Current: 361/23
• CPC Class Codes: H02M 1/32 Means for protecting converters other than automatic disconnection
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 5/4585 having a rectifier with controlled elements

Abstract

A battery voltage is increased in a converter and is input to an inverter that supplies a motor with a motor drive current. A control unit detects input and output voltages of the converter from outputs of voltage sensors and controls the switching in the converter in accordance with the detected input and output voltages. When one of the sensors fails, the control unit estimates the voltage that would have otherwise been detected by the failed voltage sensor based on the switching state in the converter and the voltage detected by the other voltage sensor.

Claims

1. A voltage conversion system comprising:

a converter that converts a voltage;

a converter control portion that variably controls widths of the voltage to be converted in the converter;

an input voltage sensor that detects an input voltage of the converter;

an output voltage sensor that detects an output voltage of the converter; and

a control unit that determines the presence of an abnormality of the input voltage sensor or the output voltage sensor on the basis of a controlling state in which widths of the voltage to be converted is controlled by the converter control portion.

2. The system according to claim 1, wherein the control unit estimates an input voltage of the converter from a controlled state of widths of the voltage to be converted and the output voltage of the converter detected by the output voltage sensor when the abnormality of the input voltage sensor is determined.

3. The system according to claim 1, wherein the control unit estimates an output voltage of the converter from a controlled state of widths of the voltage to be converted and the input voltage of the converter detected by the input voltage sensor when the abnormality of the output voltage sensor is determined.

4. The system according to claim 1, wherein the converter is constituted of a plurality of switching elements,

the converter control portion changes widths of the voltage to be converted in the converter by controlling a switching state of the switching elements, and

the control unit determines the presence of the abnormality of the input voltage sensor or the output voltage sensor on the basis of the switching state of the switching elements.

5. The system according to claim 1, further comprising an inverter being arranged to be supplied with the voltage converted in the converter, wherein an output of the inverter is connected to an alternating current load.

6. The system according to claim 5, wherein the alternating current load is a motor for driving a vehicle.

7. A voltage conversion system comprising:

a converter that converts a voltage;

a voltage detection device that detects one of an input voltage and an output voltage of the converter;

a converter control portion that variably controls widths of the voltage to be converted in the converter; and

a control unit that estimates one of the input voltage and the output voltage of the converter that has not been detected by the voltage detection device on the basis of a controlling state in which widths of the voltage to be converted is controlled by the converter control portion.

8. The system according to claim 7, wherein the converter is constituted of a plurality of switching elements,

the converter control portion changes widths of the voltage to be converted in the converter by controlling a switching state of the switching elements, and

the control unit that determines the presence of an abnormality of the input voltage sensor or the output voltage sensor on the basis of the switching state of the switching elements.

9. The system according to claim 7 further comprising an inverter being arranged to be supplied with the voltage converted in the converter,

wherein an output of the inverter is connected to an alternating current load.

10. The system according to claim 8, wherein the alternating current load is a motor for driving a vehicle.

11. A voltage conversion method of a system comprising:

a converter that converts a voltage and is controlled to variably change widths of the voltage to be converted in the converter;

an input voltage sensor that detects an input voltage of the converter;

and an output voltage sensor that detects output voltage of the converter, the voltage conversion method comprising;

determining the presence of an abnormality of the input voltage sensor or the output voltage sensor on the basis of a controlled state of widths of the voltage to be converted in the converter.

12. A voltage conversion method of a system comprising:

a converter that converts a voltage and is controlled to variably change widths of the voltage to be converted in the converter; and

a voltage detection device that detects one of an input voltage and an output voltage of the converter, the voltage conversion method comprising;

estimating one of the input voltage and the output voltage of the converter that has not been detected by the voltage detection device on the basis of (1) a controlled state of widths of the voltage to be converted in the converter and (2) the other of the input voltage and the output voltage of the converter that has been detected by the voltage detection device.