System for determining fixation of relay

Patent metadata

Field	Value
Publication number	US-10024919-B2
Application number	US-201415021132-A
Country	US
Kind code	B2
Filing date	Sep 4, 2014
Priority date	Sep 11, 2013
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

A system for determining fixation of a relay has an electricity storage device, an electrical apparatus, a relay, a first insulation resistor, a second insulation resistor, a detection circuit, and a controller. When the relay is controlled to OFF, the controller determines, based on the voltage value detected by the detection circuit (the detected voltage value), whether or not the relay is fixed. When the detected voltage value is a voltage value that is obtained by dividing the reference voltage value by a combined resistance value and the reference resistance value, the controller determines that the relay is fixed. When the detected voltage value is a voltage value that is obtained by dividing the reference voltage value by the first resistance value and the reference resistance value, the controller determines that the relay is not fixed.

First claim

What is claimed is:

1. A system for determining fixation of a relay, the system comprising:
an electricity storage device;
an electrical apparatus;
a relay that is provided on a line connecting the electricity storage device and the electrical apparatus, the relay including a movable contact point and a fixed contact point;
a first insulation resistor having a first resistance value and disposed between the electricity storage device and a ground;
a second insulation resistor having a second resistance value and disposed between the electrical apparatus and the ground, the second resistance value being lower than the first resistance value;
a detection circuit comprising a resistance element having a reference resistance value and an alternating current (AC) supply having a reference voltage value, and configured to output an AC signal to the electricity storage device and detect a voltage value based on the AC signal; and
a controller configured to:
determine whether or not the relay is fixed based on the voltage value detected by the detection circuit, when the relay is controlled to be off,
determine that the relay is fixed when the detected voltage value is a voltage value that is obtained by dividing the reference voltage value by a combined resistance value and the reference resistance value, the combined resistance value being a combined value of the first resistance value and the second resistance value, and
determine that the relay is not fixed when the detection circuit detects a voltage value that is obtained by dividing the reference voltage value by the first resistance value and the reference resistance value, wherein

when determining, based on the detected voltage value, a decreases in the first resistance value resulting from a leak in the electricity storage device, the detection circuit outputs the AC signal of a first frequency,
when determining, based on the detected voltage value, whether or not the relay is fixed, the detection circuit outputs the AC signal of a second frequency, the second frequency being lower than the first frequency, and
when the detected voltage value that is obtained when the AC signal of the first frequency is used is equal to the detected voltage value that is obtained when the AC signal of the second frequency is used, the controller determines that output states of the AC signals from the detection circuit are abnormal.

2. The system for determining fixation according to claim 1 , wherein
the controller determines whether or not the first resistance value decreases due to the leak in the electricity storage device based on the detected voltage value, and
when the first resistance value does not decrease, the controller determines whether or not the relay is fixed.

3. The system for determining fixation according to claim 1 , wherein
the relay includes a first relay and a second relay, and the movable contact point of the first relay and the movable contact point of the second relay are mechanically connected to each other so as to be integrally operated, the first relay being provided on a line connecting a positive electrode terminal of the electricity storage device and the electrical apparatus, and the second relay being provided on a line connecting a negative electrode terminal of the electricity storage device and the electrical apparatus.

4. A system for determining fixation of a relay, the system comprising:
an electricity storage device;
an electrical apparatus;
a relay that is provided on a line connecting the electricity storage device and the electrical apparatus, the relay including a movable contact point and a fixed contact point;
a detection circuit comprising a resistance element having a reference resistance value and an alternating current (AC) supply having a reference voltage value, and configured to output an AC signal to the electricity storage device and detect a voltage value based on the AC signal; and
a controller configured to:
determine whether or not the relay is fixed based on the voltage value detected by the detection circuit, when the relay is controlled to be off,
determine that the relay is fixed when the detected voltage value is a voltage value that is obtained by dividing the reference voltage value by a combined resistance value and the reference resistance value, the combined resistance value being a combined value of a first resistance value and a second resistance value, and
determine that the relay is not fixed when the detected voltage value is a voltage value that is obtained by dividing the reference voltage value by the first resistance value and the reference resistance value, wherein
the first resistance value is a resistance value of an insulation resistance between the electricity storage device and a ground, the second resistance value is a resistance value of an insulation resistance between the electrical apparatus and the ground, and the first resistance value is higher than the second resistance value,

when determining, based on the detected voltage value, a decreases in the first resistance value resulting from a leak in the electricity storage device, the detection circuit outputs the AC signal of a first frequency,
when determining, based on the detected voltage value, whether or not the relay is fixed, the detection circuit outputs the AC signal of a second frequency, the second frequency being lower than the first frequency, and
when the detected voltage value that is obtained when the AC signal of the first frequency is used is equal to the detected voltage value that is obtained when the AC signal of the second frequency is used, the controller determines that output states of the AC signals from the detection circuit are abnormal.

5. A system for determining fixation of a relay, the system comprising:
an electricity storage device;
an electrical apparatus;
a relay that is provided on a line connecting the electricity storage device and the electrical apparatus, the relay including a movable contact point and a fixed contact point;
a first insulation resistor having a first resistance value between the electricity storage device and a ground;
a second insulation resistor having a second resistance value between the electrical apparatus and the ground, the second resistance value being lower than the first resistance value;
a detection circuit comprising a resistance element having a reference resistance value and an alternating current (AC) supply having a reference voltage value, and configured to output an AC signal to the electricity storage device and detect a voltage value based on the AC signal; and
a controller configured to:
determine whether or not the relay is fixed based on the voltage value detected by the detection circuit, when the relay is controlled to be off,
determine that the relay is fixed when a calculated resistance value calculated from the detected voltage value, the reference voltage value and the reference resistance value being a combined resistance value of the first resistance value and the second resistance value, and
determine that the relay is not fixed when the calculated resistance value is the first resistance value, wherein

when determining, based on the detected voltage value, a decreases in the first resistance value resulting from a leak in the electricity storage device, the detection circuit outputs the AC signal of a first frequency,
when determining, based on the detected voltage value, whether or not the relay is fixed, the detection circuit outputs the AC signal of a second frequency, the second frequency being lower than the first frequency, and
when the detected voltage value that is obtained when the AC signal of the first frequency is used is equal to the detected voltage value that is obtained when the AC si

Assignees

• Toyota Motor Co Ltd

Inventors

• Nishi Yuji
• Tanabe Yukinari
• Kaiya Hiroyuki
• Tanaka Hiromasa

Classifications

• G01R31/3278 Primary

  of relays, solenoids or reed switches (measuring contact resistance G01R27/205; high voltage magnetic switches G01R31/3271, G01R31/333; testing electric windings G01R31/72; monitoring of fail safe circuits H01H47/002) · CPC title

• H02H9/001

  limiting speed of change of electric quantities, e.g. soft switching on or off (progressive control of electronic switches for eliminating interferences H03K17/16) · CPC title

• G01R31/006

  on road vehicles, e.g. automobiles or trucks (testing of ignition installations peculiar to internal combustion engines F02P17/00) · CPC title

• H01H47/002

  Monitoring or fail-safe circuits · CPC title

• G01R19/0084

  Measuring voltage only · CPC title