CN-224233359-U - Overload protection circuit for charging resistor of direct current bus and direct current charging circuit

CN224233359UCN 224233359 UCN224233359 UCN 224233359UCN-224233359-U

Abstract

The embodiment of the application relates to a direct current bus charging resistor overload protection circuit and a direct current charging circuit, wherein the circuit comprises a charging resistor, a bus switch module and a switch control module; the charging resistor is arranged on the direct-current bus, the output end of the switch control module is connected with the control end of the bus switch module, at least two input ends of the switch control module are used for receiving at least two state signals, and the switch contact of the bus switch module is connected with the charging resistor in parallel. The embodiment of the application can disconnect the bus switch module and connect the charging resistor only when a plurality of conditions are met, thereby avoiding the charging resistor from being connected with a direct current bus due to abnormal conditions, overload and even damage of the charging resistor, and further improving the safety and stability of the circuit.

Inventors

ZHANG XINYI
ZHAO JUN
YANG XIANGMU

Assignees

珠海格力电器股份有限公司

Dates

Publication Date: 20260512
Application Date: 20250506

Claims (10)

1. The overload protection circuit for the direct-current bus charging resistor is characterized by comprising a charging resistor, a bus switch module and a switch control module; The charging resistor is arranged on the direct current bus; The output end of the switch control module is connected with the control end of the bus switch module, and at least two input ends of the switch control module are used for receiving at least two state signals; And the switch contact of the bus switch module is connected with the charging resistor in parallel.
2. The circuit of claim 1, wherein the switch control module comprises a logic gate unit and a transistor; At least two input terminals of the logic gate unit are respectively used for receiving at least two state signals, the output end of the logic gate unit is connected with the control end of the transistor; and the output end of the transistor is connected with the control end of the bus switch module.
3. The circuit of claim 2, wherein the logic gate unit comprises an or gate, the transistor comprises a first transistor, at least two input terminals of the or gate are respectively used for receiving the at least two status signals, an output terminal of the or gate is connected with a control terminal of the first transistor, and an output terminal of the first transistor is connected with a control terminal of the bus switch module.
4. The circuit of claim 2, wherein the logic gate unit comprises a nor gate, the transistor comprises a second transistor, at least two input terminals of the nor gate are respectively used for receiving the at least two status signals, an output terminal of the nor gate is connected to a control terminal of the second transistor, and an output terminal of the second transistor is connected to a control terminal of the bus switch module.
5. The circuit of claim 1, wherein the bus switch module comprises a normally open relay, a control terminal of the relay is connected to an output terminal of the switch control module, and a switch contact of the relay is connected in parallel with the charging resistor.
6. The circuit of claim 5, wherein the bus bar switch module further comprises a diode, the diode being antiparallel to the control terminal of the relay.
7. A direct current charging circuit, characterized in that the circuit comprises the direct current bus charging resistor overload protection circuit as claimed in any one of claims 1-6, a controller and at least two state detection modules; Each of the at least two state detection modules is respectively connected with a corresponding target sampling point in the direct current charging circuit; at least two signal acquisition ends of the controller are respectively connected with the at least two state detection modules; And at least two state signal output ends of the controller are connected with the input end of a switch control module in the direct current bus charging resistor overload protection circuit.
8. The direct current charging circuit of claim 7, wherein the at least two status detection modules comprise a state of charge detection module and a fan control module; the charging state detection module is connected with a direct current bus of the direct current charging circuit; The fan control module is connected with the charging capacitor of the direct current charging circuit in parallel.
9. A frequency converter comprising a rectifying portion, an inverting portion, and the direct current charging circuit according to claim 7 or 8, the direct current charging circuit being provided between the rectifying portion and the inverting portion.
10. An air conditioning apparatus comprising the inverter of claim 9 and a compressor having a three-phase electrical input connected to a three-phase output of the inverter.

Description

Overload protection circuit for charging resistor of direct current bus and direct current charging circuit Technical Field The application relates to the technical field of motor driving, in particular to a direct current bus charging resistor overload protection circuit and a direct current charging circuit. Background In equipment such as an air conditioning unit, a direct current charging circuit is required to drive a motor of the equipment such as a compressor. In a dc charging circuit, a charging circuit is usually provided on a dc bus to charge a capacitor in a driving circuit for a certain charging time. The charging logic is that the main loop is charged through the cement resistor when the power is on, and when the bus voltage is detected to be larger than the preset voltage value, a large relay connected with the cement resistor in parallel is attracted to short the cement resistor, so that the energy loss is reduced. However, due to abnormal conditions such as debugging control or logic control, the motor may be stopped, and the large relay may be controlled to be disconnected in a program. At this time, other modules may still operate, for example, in an air conditioning unit, an IPM module (intelligent power module ) of the fan still operates, so that a current loop is formed, and a cement resistor on the charging loop is overloaded, so that the cement resistor is damaged, and the direct current charging circuit cannot operate normally. Disclosure of utility model In view of the above, in order to solve some or all of the above technical problems, embodiments of the present application provide a dc bus charging resistor overload protection circuit, a display panel and a display device. In a first aspect, the embodiment of the application provides a direct current bus charging resistor overload protection circuit and a direct current charging circuit, wherein the circuit comprises a charging resistor, a bus switch module and a switch control module; the charging resistor is arranged on the direct-current bus, the output end of the switch control module is connected with the control end of the bus switch module, at least two input ends of the switch control module are used for receiving at least two state signals, and the switch contact of the bus switch module is connected with the charging resistor in parallel. In one possible implementation manner, the switch control module comprises a logic gate unit and a transistor, wherein at least two input ends of the logic gate unit are respectively used for receiving at least two state signals, an output end of the logic gate unit is connected with a control end of the transistor, and an output end of the transistor is connected with a control end of the bus switch module. In one possible embodiment, the logic gate unit includes an or gate, the transistor includes a first transistor, at least two input terminals of the or gate are respectively used for receiving at least two status signals, an output terminal of the or gate is connected with a control terminal of the first transistor, and an output terminal of the first transistor is connected with a control terminal of the bus switch module. In one possible embodiment, the logic gate unit includes a nor gate, the transistor includes a second transistor, at least two input terminals of the nor gate are respectively used for receiving at least two status signals, an output terminal of the nor gate is connected to a control terminal of the second transistor, and an output terminal of the second transistor is connected to a control terminal of the bus switch module. In one possible embodiment, the bus switch module comprises a normally open relay, the control terminal of which is connected to the output terminal of the switch control module, and the switch contact of which is connected in parallel to the charging resistor. In one possible embodiment, the bus bar switch module further comprises a diode connected in anti-parallel with the control terminal of the relay. In a second aspect, an embodiment of the application provides a direct current charging circuit, which comprises the direct current bus charging resistor overload protection circuit, a controller and at least two state detection modules, wherein each state detection module in the at least two state detection modules is respectively connected with a corresponding target sampling point in the direct current charging circuit, at least two signal acquisition ends of the controller are respectively connected with the at least two state detection modules, and at least two state signal output ends of the controller are connected with input ends of a switch control module in the direct current bus charging resistor overload protection circuit. In one possible implementation, the at least two state detection modules include a state of charge detection module and a fan control module, the state of charge detection module is connected with a direct cu