US 12,487,271 B2
Insulation sampling circuit and control method therefor, voltage withstand test method, and power consuming device
Xingchang Wang, Ningde (CN); Wei Tian, Ningde (CN); Zhiwei Yan, Ningde (CN); Hang Ma, Ningde (CN); and Fangyou Lu, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED, Hong Kong (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED, Hong Kong (CN)
Filed on Dec. 4, 2023, as Appl. No. 18/528,404.
Application 18/528,404 is a continuation of application No. PCT/CN2022/121858, filed on Sep. 27, 2022.
Claims priority of application No. 202111306494.2 (CN), filed on Nov. 5, 2021.
Prior Publication US 2024/0110965 A1, Apr. 4, 2024
Int. Cl. G01R 31/14 (2006.01); G01R 31/00 (2006.01)
CPC G01R 31/14 (2013.01) [G01R 31/007 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A control method for an insulation sampling circuit, wherein:
the insulation sampling circuit comprises:
a first sampling circuit, comprising: a first sampling module, a first resistor, and a first switch module, wherein:
the first resistor is connected in parallel to the first sampling module, and the first switch module is configured to control the first sampling module and/or the first resistor to be connected between a positive bus and a ground wire;
a second sampling circuit, comprising: a second sampling module, a second resistor, and a second switch module, wherein:
the second resistor is connected in parallel to the second sampling module, and the second switch module is configured to control the second sampling module and/or the second resistor to be connected between a negative bus and a ground wire; and
a voltage withstand module disposed on the ground wire and capable of controlling switching between a state where the ground wire is disconnected from the ground and a state where the ground wire is connected to the ground;
wherein:
the first sampling module performs voltage-dividing at both ends and provides a first voltage sampling point, and the first sampling circuit detects a voltage at the first voltage sampling point; and
the second sampling module performs voltage-dividing at both ends and provides a second voltage sampling point, and the second sampling circuit detects a voltage at the second voltage sampling point; and
the control method comprises:
first control: controlling the voltage withstand module of the insulation sampling circuit to enable the ground wire to be connected to the ground, controlling the first switch module of the insulation sampling circuit to enable the first sampling module to be connected between a positive bus and the ground wire, and controlling the second switch module to enable the second sampling module to be connected between a negative bus and the ground wire;
obtaining a second sampling voltage formed by the second sampling module in a state where the first control has been performed;
determining whether the ground wire is connected based on a change in the voltage value of the second sampling voltage over a period of time;
performing an insulation test when the ground wire is connected; and
outputting fault information when the ground wire is disconnected from the ground.