CN-121995204-A - Relay circuit fault detection method and relay circuit

CN121995204ACN 121995204 ACN121995204 ACN 121995204ACN-121995204-A

Abstract

The application provides a fault detection method of a relay circuit and the relay circuit, wherein the relay circuit comprises a fault detection pin, the relay circuit comprises at least one voltage transmission path, and at least one relay is arranged on each voltage transmission path; A fault condition of the relay circuit is determined based on the AC voltage signal and the DC voltage signal. The fault detection method of the relay circuit can detect the working state of the relay, realize fault detection before equipment operation, provide overhaul basis for equipment maintenance and ensure safe and reliable operation of the equipment.

Inventors

WANG HUAN
CHEN QI
HUI JI
DUAN YOUCHAO

Assignees

西安麦格米特电气有限公司

Dates

Publication Date: 20260508
Application Date: 20260104

Claims (13)

1. A method of fault detection for a relay circuit, the relay circuit including a fault detection pin, the relay circuit including at least one voltage transmission path, each voltage transmission path having at least one relay disposed thereon, the method comprising: Detecting alternating current voltage signals and direct current voltage signals corresponding to each voltage transmission channel in a first working state or a second working state through the fault detection pins respectively; A fault state of the relay circuit is determined based on the ac voltage signal and the dc voltage signal.
2. The method according to claim 1, wherein detecting, by the fault detection pin, the ac voltage signal and the dc voltage signal corresponding to each of the voltage transmission paths in the first operating state or the second operating state, respectively, includes: Controlling all relays in each voltage transmission path to be in an off state so that the relay circuit is in the first working state; detecting an alternating current voltage signal and a direct current voltage signal of each voltage transmission channel; Determining a fault state of the relay circuit based on the ac voltage signal and the dc voltage signal, comprising: and responding to the fact that all target voltage signals are identical and absolute values are larger than a first preset value, and the absolute value of a difference value between an associated voltage signal corresponding to the same voltage transmission channel and the target voltage signal is smaller than a second preset value, and determining that all relays in the voltage transmission channel corresponding to the associated voltage signal are in a bonding state, wherein the target voltage signal is one of the direct current voltage signal and the alternating current voltage signal, and the associated voltage signal is the other one of the direct current voltage signal and the alternating current voltage signal.
3. The method of detection of claim 2, wherein determining a fault condition of the relay circuit based on the ac voltage signal and the dc voltage signal comprises: And responding to the fact that the sum of all the target voltage signals is equal to the first preset value, and if the absolute value of any one of the target voltage signals is larger than the first preset value, determining that all the relays in all the voltage transmission paths are in a bonding state.
4. The detection method according to claim 2, wherein determining a fault state of the relay circuit based on the alternating voltage signal and the target voltage signal includes: and responding to the sum of the first target voltage signal and the second target voltage signal to be equal to the preset multiple of the third target voltage signal, and determining that all relays in the voltage transmission paths corresponding to the first target voltage signal and the second target voltage signal are in a bonding state.
5. The method according to claim 1, wherein detecting the ac voltage signal and the dc voltage signal corresponding to each of the voltage transmission paths in the first operating state or the second operating state, respectively, through the fault detection pin includes; Controlling part of relays in each voltage transmission path to be in a suction state, and the rest of relays to be in a disconnection state so as to enable the relay circuit to be in the second working state; detecting an alternating current voltage signal and a direct current voltage signal of each voltage transmission channel; Determining a fault state of the relay circuit based on the ac voltage signal and the dc voltage signal, comprising: And responding to the fact that all target voltage signals are identical and absolute values are larger than a first preset value, and the absolute value of a difference value between an associated voltage signal corresponding to the same voltage transmission channel and the target voltage signal is smaller than a second preset value, and determining that the relay in an off state in the voltage transmission channel corresponding to the associated voltage signal is in a bonding state, wherein the target voltage signal is one of the direct current voltage signal and the alternating current voltage signal, and the associated voltage signal is the other of the direct current voltage signal and the alternating current voltage signal.
6. The method of detecting according to claim 5, wherein determining a fault state of the relay circuit based on the alternating voltage signal and the target voltage signal comprises: and responding to the fact that the sum of all the target voltage signals is equal to the first preset value, and if the absolute value of any one of the target voltage signals is larger than the first preset value, determining that all the relays in the disconnection state in the voltage transmission paths are in the adhesion state.
7. The method of detecting according to claim 5, wherein determining a fault state of the relay circuit based on the alternating voltage signal and the target voltage signal comprises: And determining that the relay in the disconnection state in the voltage transmission path corresponding to the first target voltage signal and the second target voltage signal is in the adhesion state if the sum of the first target voltage signal and the second target voltage signal is equal to the preset multiple of the third target voltage signal.
8. A relay circuit, comprising: the voltage transmission path is provided with a relay, a first end of the voltage transmission path is connected with a direct current side, and a second end of the voltage transmission path is connected with an alternating current side; The relay circuit comprises a voltage transmission path, a detection unit and a relay circuit, wherein the voltage transmission path comprises a plurality of detection paths, the first ends of the detection paths are respectively connected with the first ends of the voltage transmission paths and the second ends of the voltage transmission paths, the second ends of the detection paths are used as fault detection pins, and the fault detection pins are used for detecting alternating current voltage signals and direct current voltage signals corresponding to the voltage transmission paths in a first working state or a second working state, so that the fault state of the relay circuit is determined based on the alternating current voltage signals and the direct current voltage signals by using the fault detection method according to any one of claims 1-7.
9. The relay circuit of claim 8, wherein the detection unit comprises a first detection unit and a second detection unit, The first detection unit comprises a plurality of first detection paths, wherein the first end of each first detection path is connected between the direct current side and the relay, and the second end of each first detection path is interconnected to serve as a first fault detection pin; The second detection unit comprises a plurality of second detection paths, wherein the first end of each second detection path is connected between the alternating current side and the relay, the second end of each second detection path is interconnected to serve as a second fault detection pin, and the second fault detection pin is used for detecting the alternating current voltage signal in the first working state or the second working state.
10. The relay circuit of claim 9, wherein each of the first detection paths comprises: a capacitor or resistor connected in series between the DC side and the first fault detection pin, or And a capacitor and a resistor connected in parallel between the direct current side and the first fault detection pin.
11. The relay circuit of claim 9, wherein each of the second detection paths comprises: a capacitor connected in series between the AC side and the second fault detection pin, or And a capacitor and a resistor connected in parallel between the alternating current side and the second fault detection pin.
12. The relay circuit of claim 9, wherein the second detection unit further comprises: And the filtering unit is connected between the second fault detection pin and the grounding end.
13. The relay circuit of claim 9, wherein the first fault detection pin and the second fault detection pin are interconnected.

Description

Relay circuit fault detection method and relay circuit Technical Field The present application relates to the field of power electronics, and in particular, to a relay circuit and a fault detection method thereof. Background In photovoltaic and energy storage PCS equipment, a relay is used as an indispensable device, the breaking and sucking reliability of the relay directly determines the operation safety reliability of the equipment, in the current main stream inverter equipment, an alternating current port relay is basically connected in series with two groups of alternating current ports, the scheme mainly considers that sufficient electric gap redundancy exists between alternating current and direct current networks when the relay is disconnected, however, under abnormal conditions such as high current and the like, the relay contacts are adhered, if the adhesion failure of the relay contacts can not be detected and reported in time, the failure can be further diffused when the equipment is operated, and the reliability of the equipment is affected. Disclosure of Invention The application mainly provides a fault detection method of a relay circuit and the relay circuit, the fault detection method of the relay circuit can detect the working state of the relay, the fault detection before the operation of the equipment is realized, an overhaul basis is provided for equipment maintenance, and the safe and reliable operation of the equipment is ensured. In order to solve the technical problems, the first technical scheme adopted by the application is to provide a fault detection method of a relay circuit, wherein the relay circuit comprises a fault detection pin, the relay circuit comprises at least one voltage transmission path, and each voltage transmission path is provided with at least one relay, and the method comprises the following steps: detecting alternating current voltage signals and direct current voltage signals corresponding to each voltage transmission path in a first working state or a second working state through a fault detection pin respectively; A fault condition of the relay circuit is determined based on the AC voltage signal and the DC voltage signal. In an embodiment, detecting, by the fault detection pin, an ac voltage signal and a dc voltage signal corresponding to each voltage transmission path in the first operating state or the second operating state, respectively, includes: Controlling all relays in each voltage transmission path to be in an off state so that a relay circuit is in a first working state; detecting an alternating voltage signal and a direct voltage signal of each voltage transmission channel; Determining a fault condition of the relay circuit based on the ac voltage signal and the dc voltage signal, comprising: And responding to the fact that all target voltage signals are identical and absolute values are larger than a first preset value, and the absolute value of a difference value between an associated voltage signal corresponding to the same voltage transmission channel and the target voltage signal is smaller than a second preset value, and determining that all relays in the voltage transmission channel corresponding to the associated voltage signal are in a bonding state, wherein the target voltage signal is one of a direct-current voltage signal and an alternating-current voltage signal, and the associated voltage signal is the other of the direct-current voltage signal and the alternating-current voltage signal. In one embodiment, determining a fault condition of a relay circuit based on an ac voltage signal and a dc voltage signal includes: And responding to the fact that the sum of all the target voltage signals is equal to a first preset value, and if the absolute value of any one of the target voltage signals is larger than the first preset value, determining that all the relays in all the voltage transmission paths are in an adhesion state. In one embodiment, determining a fault condition of the relay circuit based on the ac voltage signal and the target voltage signal includes: And responding to the sum of the first target voltage signal and the second target voltage signal to be equal to the preset multiple of the third target voltage signal, and determining that all relays in the voltage transmission paths corresponding to the first target voltage signal and the second target voltage signal are in an adhesion state. In an embodiment, detecting an ac voltage signal and a dc voltage signal corresponding to each voltage transmission path in a first operating state or a second operating state through a fault detection pin, respectively, including; Controlling part of relays in the relays in each voltage transmission path to be in a suction state, and the rest of relays to be in a disconnection state so as to enable a relay circuit to be in a second working state; detecting an alternating voltage signal and a direct voltage signal of each voltage trans