Relay diagnosis circuit

Patent metadata

Field	Value
Publication number	US-11204386-B2
Application number	US-201816620643-A
Country	US
Kind code	B2
Filing date	Oct 15, 2018
Priority date	Nov 7, 2017
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

A relay diagnosis circuit capable of diagnosing whether a relay connected to a negative electrode of a battery pack normally operates using voltage applied from a positive electrode of the battery pack.

First claim

The invention claimed is:

1. A relay diagnosis circuit for diagnosing whether a relay controlling a connection state between a battery pack and a load normally operates, comprising:
a first switch;
a second switch; and
a measurement unit connected in parallel with the second switch,
wherein the relay diagnosis circuit is connected between a positive electrode side and a negative electrode side of the battery pack and is configured to be connected in parallel with the load,
wherein the relay is connected between the negative electrode side of the battery pack and the load,
wherein a first state of the first switch is configured to direct a path of current from the battery pack towards the second switch and the measurement unit, and a second state of the first switch is configured to direct the path of current from the battery pack towards the load;
wherein a first state of the second switch is configured to direct the path of current towards the relay when the first switch is in the first state; and
wherein the measurement unit is configured to measure voltage applied through the relay in response to the second switch being in the first state.

2. The relay diagnosis circuit of claim 1 , wherein the measurement unit is configured to measure voltage applied from the battery pack when the first switch is in an on state and the second switch is in an off state.

3. The relay diagnosis circuit of claim 2 , wherein the measurement unit is configured to diagnose a normal operation of either the battery pack or the relay based on the measured voltage applied from the battery pack,
wherein:
when the second switch is in the on state, the measurement unit is configured to diagnose a normal operation of the relay, and
when the second switch is in the off state, the measurement unit is configured to diagnose a normal operation of the battery pack.

4. The relay diagnosis circuit of claim 1 , further comprising:
a plurality of resistors, each of the plurality of resistors serially connected to a respective one of the first switch, the second switch, and the measurement unit.

5. The relay diagnosis circuit of claim 1 , wherein diagnosing whether a relay controlling a connection state between a battery pack and a load normally operates is determined based on a range of reference voltage, wherein the range of reference voltage is different depending on whether the first switch is in the first state or the second state.

6. The relay diagnosis circuit of claim 1 , wherein the measurement unit is a converter configured to convert the applied voltage into a digital signal.

Assignees

• Lg Chemical Ltd

Inventors

• Park Jaedong
• Cho Hyunki
• Lee Sang Hoon
• Choi Yean Sik

Classifications

• Y02T10/70

  Energy storage systems for electromobility, e.g. batteries · CPC title

• 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

• G01R31/3275 Primary

  Fault detection or status indication · CPC title

• G01R19/165

  Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values · CPC title

• B60L1/04

  fed by the power supply line · CPC title