CN-115987076-B - Electrical equipment and protection circuit thereof

CN115987076BCN 115987076 BCN115987076 BCN 115987076BCN-115987076-B

Abstract

The application discloses an electrical device and a protection circuit thereof. The protection circuit of the electrical equipment comprises an inverter circuit, a rectifier bridge circuit and an anti-interference circuit, wherein the inverter circuit is connected with an electric load and used for inverting direct current into alternating current to supply power for the electric load, the rectifier bridge circuit is connected with the inverter circuit and used for rectifying the alternating current into direct current, and the anti-interference circuit is respectively connected with the rectifier bridge circuit and a three-phase alternating current power supply and used for eliminating interference generated in the electricity utilization process of the electric load.

Inventors

HUANG WEI
YANG FAN
YANG XIANGMU

Assignees

珠海格力电器股份有限公司

Dates

Publication Date: 20260505
Application Date: 20221202

Claims (7)

1. A protection circuit for an electrical device, the protection circuit comprising: The inverter circuit is connected with the electric load and is used for inverting the direct current into alternating current and supplying power for the electric load; The rectifier bridge circuit is connected with the inverter circuit and used for rectifying alternating current into direct current; The anti-interference circuit is respectively connected with the rectifier bridge circuit and the three-phase alternating current power supply and is used for eliminating interference generated in the power utilization process of the power utilization load; When the operating frequency of the power utilization load is lower than a preset frequency or the operating load is lower than a first preset load, the control chip is used for outputting high level to the first relay, the second relay and the third relay so as to close the first relay, the second relay and the third relay; When the operation load of the electricity load is higher than a second preset load, the control chip is used for outputting high level to the first relay, the second relay and the third relay so as to close the first relay, the second relay and the third relay; The control chip is used for outputting a low level to the first relay, the second relay and the third relay to disconnect the first relay, the second relay and the third relay when the operation load of the electricity load changes from being higher than a second preset load to be lower than a first preset load or is in a shutdown process, wherein the second preset load is not smaller than the first preset load; the first relay, the second relay and the third relay are respectively used for controlling the on-off of a first control sub-circuit, a second control sub-circuit and a third control sub-circuit in the anti-interference circuit.
2. The protection circuit of claim 1, wherein the tamper-proof circuit comprises: The three-phase alternating current power supply comprises a first inductor, a second inductor and a third inductor, wherein one end of the first inductor is connected with a first phase of the three-phase alternating current power supply, one end of the second inductor is connected with a second phase of the three-phase alternating current power supply, and one end of the third inductor is connected with a third phase of the three-phase alternating current power supply; the first control sub-circuit, the second control sub-circuit and the third control sub-circuit, one end of the first control sub-circuit, one end of the third control sub-circuit and the other end of the first inductor are connected to a first node, the other end of the first control sub-circuit, one end of the second control sub-circuit and the other end of the second inductor are connected to a second node, and the other end of the second control sub-circuit, the other end of the third control sub-circuit and the other end of the third inductor are connected to a third node.
3. The protection circuit of claim 2, wherein, The first control sub-circuit comprises a first relay, a first capacitor, a second capacitor and a first resistor, one end of the first relay is connected with the first node, one end of the first capacitor and one end of the second capacitor are connected with the other end of the first relay, one end of the first resistor is connected with the other end of the second capacitor, and the other end of the first resistor and the other end of the first capacitor are connected with the second node; The second control sub-circuit comprises a second relay, a third capacitor, a fourth capacitor and a second resistor, one end of the second relay is connected with the second node, one end of the third capacitor and one end of the fourth capacitor are connected with the other end of the second relay, one end of the second resistor is connected with the other end of the fourth capacitor, and the other end of the second resistor and the other end of the third capacitor are connected with the third node; the third control sub-circuit comprises a third relay, a fifth capacitor, a sixth capacitor and a third resistor, one end of the third relay is connected with the first node, one end of the fifth capacitor and one end of the sixth capacitor are connected with the other end of the third relay, one end of the third resistor is connected with the other end of the sixth capacitor, and the other end of the third resistor and the other end of the fifth capacitor are connected with the third node.
4. A protection circuit according to claim 3, wherein the protection circuit further comprises: The voltage sampling circuit comprises a fourth resistor and a fifth resistor, wherein one end of the fourth resistor and one end of the fifth resistor are connected to a fourth node, the other end of the fourth resistor and the inverter circuit are connected to a fifth node, and the other end of the fifth resistor and the inverter circuit are connected to a sixth node; And the control chip is respectively connected with the first relay, the second relay, the third relay and the fourth node and is used for determining the running state of the power utilization load according to the voltage of the fourth node so as to control the on-off of the first relay, the second relay and the third relay.
5. The protection circuit of claim 4, wherein the rectifier bridge circuit comprises: the cathode of the first diode, the cathode of the second diode and the cathode of the third diode are connected with the fifth node, the anode of the fourth diode, the anode of the fifth diode and the anode of the sixth diode are connected with the sixth node, the anode of the first diode and the cathode of the fourth diode are connected with the first node, the anode of the second diode and the cathode of the fifth diode are connected with the second node, and the anode of the third diode and the cathode of the sixth diode are connected with the third node; and a seventh capacitor connected between the fifth node and the sixth node.
6. The protection circuit of claim 4, wherein, And under the condition that the power utilization load is in a standby state, the control chip is used for outputting a low level to the first relay, the second relay and the third relay so as to disconnect the first relay, the second relay and the third relay.
7. An electrical device comprising the protection circuit of the electrical device of any one of claims 1 to 6.

Description

Electrical equipment and protection circuit thereof Technical Field The application relates to the technical field of electric appliance control, in particular to electric appliance equipment and a protection circuit thereof. Background The variable frequency air conditioner can generate interference in the use process, and the coping modes of partial manufacturers mainly comprise two modes, namely an active full-bridge treatment scheme and a passive treatment mode, and no matter which mode is used, the operation instability and even board burning can be caused by the fluctuation of the power grid quality and large interference in the use process. Aiming at the technical problem of poor operation stability of the electric appliance in the related technology, no effective solution is proposed at present. Disclosure of Invention The embodiment of the application provides electrical equipment and a protection circuit thereof, which are used for solving the technical problem of poor operation stability of an electrical appliance in the related technology. In order to solve the technical problems, according to one aspect of the embodiment of the application, a protection circuit of electrical equipment is provided, which comprises an inverter circuit, a rectifier bridge circuit and an anti-interference circuit, wherein the inverter circuit is connected with an electric load and is used for inverting direct current into alternating current to supply power for the electric load, the rectifier bridge circuit is connected with the inverter circuit and is used for rectifying the alternating current into direct current, and the anti-interference circuit is respectively connected with the rectifier bridge circuit and a three-phase alternating current power supply and is used for eliminating interference generated in the electric load power utilization process. Optionally, the anti-interference circuit comprises a first inductor, a second inductor and a third inductor, wherein one end of the first inductor is connected with a first phase of the three-phase alternating current power supply, one end of the second inductor is connected with a second phase of the three-phase alternating current power supply, one end of the third inductor is connected with a third phase of the three-phase alternating current power supply, one end of the first control sub-circuit, one end of the third control sub-circuit and the other end of the first inductor are connected with a first node, the other end of the first control sub-circuit, one end of the second control sub-circuit and the other end of the second inductor are connected with a second node, and the other end of the second control sub-circuit, the other end of the third control sub-circuit and the other end of the third inductor are connected with a third node. Optionally, the first control sub-circuit comprises a first relay, a first capacitor, a second capacitor and a first resistor, one end of the first relay is connected with the first node, one end of the first capacitor and one end of the second capacitor are connected with the other end of the first relay, one end of the first resistor is connected with the other end of the second capacitor, the other end of the first resistor and the other end of the first capacitor are connected with the second node, the second control sub-circuit comprises a second relay, a third capacitor, a fourth capacitor and a second resistor, one end of the second relay is connected with the second node, one end of the third capacitor and one end of the fourth capacitor are connected with the other end of the second relay, one end of the second resistor is connected with the other end of the fourth capacitor, the other end of the second resistor and the other end of the third capacitor are connected with the third node, the third control sub-circuit comprises a third capacitor, a fourth capacitor and a third resistor, one end of the third capacitor is connected with the other end of the third capacitor, and the other end of the third capacitor is connected with the third node. Optionally, the protection circuit further comprises a voltage sampling circuit, and a control chip, wherein the voltage sampling circuit comprises a fourth resistor and a fifth resistor, one end of the fourth resistor and one end of the fifth resistor are connected to a fourth node, the other end of the fourth resistor and the inverter circuit are connected to a fifth node, the other end of the fifth resistor and the inverter circuit are connected to a sixth node, and the control chip is respectively connected with the first relay, the second relay, the third relay and the fourth node and is used for determining the running state of the power load according to the voltage of the fourth node so as to control the on-off of the first relay, the second relay and the third relay. Optionally, the rectifier bridge circuit comprises a first diode, a second diode, a third diode, a f