CN218412789U

CN218412789U - Vehicle-mounted inverter insulation resistance detection circuit

Info

Publication number: CN218412789U
Application number: CN202221408187.5U
Authority: CN
Inventors: 祁峰; 秦心华; 吴泽虎; 刘祁
Original assignee: Shanghai Qiangsong Aerospace Technology Co ltd
Current assignee: Shanghai Qiangsong Aerospace Technology Co ltd
Priority date: 2022-06-07
Filing date: 2022-06-07
Publication date: 2023-01-31
Anticipated expiration: 2032-06-07

Abstract

The utility model belongs to the technical field of on-vehicle dc-to-ac converter insulation resistance detection circuitry, a vehicle inverter insulation resistance detection circuitry is disclosed, including output circuit and comparison circuit, output circuit's output is connected comparison circuit's input, comparison circuit is used for comparing output circuit output's voltage and setting value, comparison circuit's setting value is 2.5V, output circuit includes live wire L and zero line N, and electric capacity C1, electric capacity C2, diode D1 and diode D2, electric capacity C1, electric capacity C2 and diode D2 series connection, electric capacity C1 is parallelly connected with diode D1, the last voltage of electric capacity C1 is UC1, and the last voltage of electric capacity C2 is UC2. The utility model discloses an electronic components such as electric capacity, resistance, diode have cancelled the circuit that needs the relay switching, but real time monitoring insulation resistance trouble with greatly reduced cost.

Description

Vehicle-mounted inverter insulation resistance detection circuit

Technical Field

The utility model belongs to the technical field of on-vehicle dc-to-ac converter insulation resistance detection circuitry, concretely relates to on-vehicle dc-to-ac converter insulation resistance detection circuitry.

Background

In the existing inverter, as shown in fig. 2, one or more groups of resistors are switched through a relay, the insulation resistance is calculated by comparing the change of the insulation resistance before and after the switching of the relay, and the mode of calculating the switching resistance of the relay is adopted, so that the inverter is short in service life, large in space and high in cost, and the insulation resistance cannot be monitored in real time, so that certain potential safety hazards are caused. The vehicle-mounted inverter has certain requirements on volume, cost, service life and personal safety, and the current similar products cannot meet the requirements.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an on-vehicle dc-to-ac converter insulation resistance detection circuitry to solve the current mode that adopts relay switching resistance to calculate, the life-span is short, and the space is big, and is with high costs, and can not real-time supervision insulation resistance, lead to certain potential safety hazard, and on-vehicle dc-to-ac converter has certain requirement to volume, cost, life-span and personal safety, the unable problem that satisfies the needs of current like product.

In order to achieve the above purpose, the utility model provides a following technical scheme: the vehicle-mounted inverter insulation resistance detection circuit comprises an output circuit and a comparison circuit, wherein the output end of the output circuit is connected with the input end of the comparison circuit, and the comparison circuit is used for comparing the voltage output by the output circuit with a set value.

As the utility model relates to an on-vehicle dc-to-ac converter insulation resistance detection circuitry is preferred, comparison circuit's setting value is 0.1 ~ 5V.

As the utility model relates to an on-vehicle dc-to-ac converter insulation resistance detection circuitry is preferred, comparison circuit's setting value is 2.5V.

As the utility model relates to an on-vehicle dc-to-ac converter insulation resistance detection circuitry is preferred, output circuit includes live wire L and zero line N, and electric capacity C1, electric capacity C2, diode D1 and diode D2, electric capacity C1, electric capacity C2 and diode D2 series connection, electric capacity C1 is parallelly connected with diode D1, the last voltage of electric capacity C1 is UC1, and the last voltage of electric capacity C2 is UC2.

As the utility model relates to an on-vehicle dc-to-ac converter insulation resistance detection circuitry is preferred, comparison circuit includes resistance R2, resistance R1 and voltage comparator U1A, resistance R2 connects in output circuit's output, resistance R2 establishes ties with voltage comparator U1A, resistance R2 establishes ties with resistance R1, resistance R1 connects in parallel with voltage comparator U1A, resistance R1's output ground connection.

As the utility model relates to a vehicle-mounted inverter insulation resistance detection circuitry preferably, works as when UC1 > UC2, output circuit's output terminal voltage is UC1, works as when UC1< UC2, output circuit's output terminal voltage is UC2.

As the utility model relates to an on-vehicle dc-to-ac converter insulation resistance detection circuitry is preferred, under the normal conditions, UC1= UC2, and the voltage of resistance R2 output is less than the setting value, and voltage comparator U1A exports low level, breaks down when live wire L or zero line N to the resistance of ground, and when the voltage of resistance R2 output was greater than the setting value, voltage comparator U1A exported high level, sent insulation fault and warns.

Compared with the prior art, the utility model, following beneficial effect has: electronic components such as capacitors, resistors, diodes and the like are adopted, circuits needing relay switching are omitted, cost is greatly reduced, and insulation resistance faults can be monitored in real time.

Drawings

Fig. 1 is a schematic diagram of the circuit structure of the present invention;

fig. 2 is a schematic circuit diagram of the prior art.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts all belong to the protection scope of the present invention.

Referring to fig. 1, the present invention provides the following technical solutions: the vehicle-mounted inverter insulation resistance detection circuit comprises an output circuit and a comparison circuit, wherein the output end of the output circuit is connected with the input end of the comparison circuit, and the comparison circuit is used for comparing the voltage output by the output circuit with a set value.

Specifically, the setting value of the comparison circuit is 0.1 to 5V, preferably, the setting value is 2.5V, and it should be noted that the setting value of the comparison circuit may also be 0.1V, 2V, 3V, 4V or 5V, as long as the setting value is within the protection range of the present embodiment.

Specifically, output circuit includes live wire L and zero line N, and electric capacity C1, electric capacity C2, diode D1 and diode D2, electric capacity C1, electric capacity C2 and diode D2 series connection, electric capacity C1 is parallelly connected with diode D1, voltage on the electric capacity C1 is UC1, and the voltage on the electric capacity C2 is UC2.

Specifically, the comparison circuit includes resistance R2, resistance R1 and voltage comparator U1A, resistance R2 connects in output circuit's output, resistance R2 and voltage comparator U1A establish ties, resistance R2 and resistance R1 establish ties, resistance R1 and voltage comparator U1A are parallelly connected, resistance R1's output ground.

Specifically, when UC1 > UC2, the output terminal voltage of the output circuit is UC1, and when UC1< UC2, the output terminal voltage of the output circuit is UC2.

Specifically, under normal conditions, UC1= UC2, the voltage at the output end of the resistor R2 is smaller than a set value, the voltage comparator U1A outputs a low level, and when the resistance of the live line L or the zero line N to the ground fails and the voltage at the output end of the resistor R2 is greater than the set value, the voltage comparator U1A outputs a high level to issue an insulation failure warning.

In this embodiment, as shown in fig. 1, UC1 represents the voltage across the capacitor C1; UC2 represents the voltage across capacitor C2; ULN denotes the voltage between L, N, where UC1+ UC2= ULN; due to the presence of the diode D1 and the diode D2, the voltage at the point a is the higher of the voltages UC1 and UC2, and in a normal state, UC1= UC2, the voltage comparator outputs a low level when the point B is lower than 2.5V. When the resistance of L or N to the ground is in fault, the voltages on UC1 and UC2 are changed, one is increased and the other is decreased, so that the voltage at the point A is increased, and when the voltage at the point B exceeds 2.5V, the voltage comparator outputs high level to send an insulation fault alarm. In the embodiment, electronic components such as capacitors, resistors and diodes are adopted, circuits needing relay switching are omitted, the cost is greatly reduced, and the insulation resistor fault can be monitored in real time.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The vehicle-mounted inverter insulation resistance detection circuit is characterized by comprising an output circuit and a comparison circuit, wherein the output end of the output circuit is connected with the input end of the comparison circuit, and the comparison circuit is used for comparing the voltage output by the output circuit with a set value.

2. The on-vehicle inverter insulation resistance detection circuit according to claim 1, wherein a set value of the comparison circuit is 0.1 to 5V.

3. The vehicle-mounted inverter insulation resistance detection circuit according to claim 2, wherein the set value of the comparison circuit is 2.5V.

4. The on-vehicle inverter insulation resistance detection circuit of claim 1, 2 or 3, characterized in that, the output circuit includes live wire L and zero line N, and electric capacity C1, electric capacity C2, diode D1 and diode D2, electric capacity C1, electric capacity C2 and diode D2 are connected in series, electric capacity C1 and diode D1 are parallelly connected, the voltage on electric capacity C1 is UC1, the voltage on electric capacity C2 is UC2.

5. The vehicle-mounted inverter insulation resistance detection circuit according to claim 4, wherein the comparison circuit comprises a resistor R2, a resistor R1 and a voltage comparator U1A, the resistor R2 is connected to the output end of the output circuit, the resistor R2 is connected in series with the voltage comparator U1A, the resistor R2 is connected in series with the resistor R1, the resistor R1 is connected in parallel with the voltage comparator U1A, and the output end of the resistor R1 is grounded.

6. The on-board inverter insulation resistance detection circuit of claim 5, wherein when UC1 > UC2, the voltage at the output end of said output circuit is UC1, and when UC1< UC2, the voltage at the output end of said output circuit is UC2.

7. The on-vehicle inverter insulation resistance detection circuit according to claim 6, wherein under normal conditions, UC1= UC2, the voltage at the output end of the resistor R2 is smaller than a set value, the voltage comparator U1A outputs a low level, and when the resistance of the live line L or the neutral line N to the ground fails and the voltage at the output end of the resistor R2 is greater than the set value, the voltage comparator U1A outputs a high level to issue an insulation failure warning.