CN217159542U

CN217159542U - Common-mode surge voltage impact resistance circuit of air conditioner variable frequency controller

Info

Publication number: CN217159542U
Application number: CN202121230121.7U
Authority: CN
Inventors: 俞超辉; 张泉宏; 刘宏波
Original assignee: Guangzhou Tianjia Environmental Control Equipment Co ltd
Current assignee: Guangzhou Tianjia Environmental Control Equipment Co ltd
Priority date: 2021-06-03
Filing date: 2021-06-03
Publication date: 2022-08-09
Anticipated expiration: 2031-06-03

Abstract

The utility model relates to a common mode surge voltage impact resistance circuit of an air conditioner frequency conversion controller, which comprises a rectifier bridge, wherein an external alternating current power supply is rectified to form a direct current bus P-N; the direct current bus P-N is connected with a power device of the controller; a surge suppression loop is arranged between the external alternating current power supply and the rectifier bridge; and a voltage clamping device and a resistor R1 are arranged between the direct current buses P-N. The utility model discloses can effectively clear away the uncertainty of the damage device that exists when perhaps actually meeting with the thunderbolt surge in the surge test, guarantee converter safe and reliable's operation reduces development stage test cost and after-sale maintenance cost, is worth promoting.

Description

Common-mode surge voltage impact resistance circuit of air conditioner variable frequency controller

Technical Field

The utility model relates to a circuit structure, especially an air conditioner converter circuit, specific anti common mode surge voltage impulse circuit of air conditioner variable frequency controller that says so.

Background

According to the national standard, the AC power port is required to meet the surge impact capable of bearing the lightning surge. The lightning surge includes a common mode surge and a differential mode surge. The common mode surge is a surge between a line and the ground, and the differential mode surge is a surge between the line and the ground. The surge suppression loop of the inverter air conditioner has to have a lightning surge suppression function.

At present, common mode surge suppression measures are generally to add a voltage dependent resistor and a discharge tube between a phase line and a zero line to the ground in a combined mode; and a piezoresistor is added between the phase line and the zero line in the differential touch surge suppression measure. However, when the common mode surge is suppressed, the surge suppression circuit is connected in series with the gas discharge tube AS1, so that the operation time is prolonged, and the surge voltage in a short time runs into the rear-end circuit, which threatens the power device of the rear-end circuit.

Therefore, improvements are needed to make the circuit more stable and reliable.

SUMMERY OF THE UTILITY MODEL

The utility model aims at prior art not enough, provide an air conditioner frequency conversion controller's anti common mode surge voltage impulse circuit, can clear away in the surge test or actually exist the uncertainty of damaging the device when meeting with the thunderbolt surge, guarantee converter safe and reliable's operation.

The technical scheme of the utility model is that:

a common-mode surge voltage impact resistance circuit of an air conditioner variable frequency controller comprises a rectifier bridge, a rectifier bridge and a rectifier bridge, wherein an external alternating current power supply is rectified to form a direct current bus P-N; the direct current bus P-N is connected with a power device of the controller; a surge suppression loop is arranged between the external alternating current power supply and the rectifier bridge; and a voltage clamping device and a resistor R1 are arranged between the direct current buses P-N.

Furthermore, the external alternating current power supply is a single-phase power supply and comprises a phase line, a zero line and a ground; the surge suppression loop comprises the following connections: a voltage dependent resistor RV1 is arranged between the phase line and the zero line, and the phase line is connected to the ground after passing through a voltage dependent resistor RV3 and a discharge tube; the neutral wire is connected to the ground after passing through a piezoresistor RV2 and the discharge tube.

Further, the external alternating current power supply is a three-phase power supply and comprises a phase line L1, a phase line L2, a phase line L3, a zero line and a ground; the surge suppression loop comprises the following connections: phase line L3 with be equipped with piezo-resistor RV1 between the zero line, phase line L2 with be equipped with piezo-resistor RV2 between the zero line, phase line L1 with be equipped with piezo-resistor RV3 between the zero line, the zero line with be equipped with discharge tube between the earth.

Further, the voltage clamping device is a TVS diode or a piezoresistor RV 4.

Further, the discharge tube is a gas discharge tube.

Further, the resistor R1 is a fixed resistor.

Further, a capacitor E1 is arranged between the direct current buses P-N.

The utility model has the advantages that:

the utility model relates to a rationally, simple structure, convenient to use can effectively clear away the uncertainty of the damage device that exists when perhaps actually meeting with the thunderbolt surge in the surge test, and the operation of guarantee converter safe and reliable reduces development stage test cost and after-sales maintenance cost, is worth promoting.

Drawings

Fig. 1 is a schematic view of a first embodiment of the present invention.

Fig. 2 is a schematic diagram of a second embodiment of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and examples.

Embodiment one, as shown in fig. 1.

An external alternating current power supply of the common-mode surge voltage impact resistance circuit of the air conditioner frequency conversion controller is a single-phase power supply and comprises a phase line L, a zero line N and a ground PE.

And the phase line L and the zero line N form a direct current bus P-N after passing through the rectifier bridge. The direct current bus P-N is connected with a power device of the controller, and normal work of the power device is guaranteed.

And a surge suppression loop is arranged between the external alternating current power supply and the rectifier bridge, so that a power supply port can bear surge impact. The surge suppression loop comprises the following connections: a voltage dependent resistor RV1 is arranged between the phase line L and the zero line N; the phase line L is connected to the ground PE after passing through a voltage dependent resistor RV3 and a gas discharge tube AS 1; the neutral wire N is connected to the ground PE after passing through a voltage dependent resistor RV2 and the gas discharge tube AS 1.

And a voltage clamping device and a fixed resistor R1 are arranged between the direct current buses P-N. Wherein, the voltage clamping device is a TVS diode or a piezoresistor RV 4.

And a capacitor E1 is arranged between the direct current buses P-N.

The rectifier bridge is formed by connecting diodes D1, D2, D3 and D4 in series.

The utility model discloses a working process does:

in the simulation of common mode surge test, voltage is applied between L → PE or N → PE. Because the gas discharge tube AS1 is connected in series in the surge suppression loop, the action time is prolonged, so that the surge voltage in a short time runs into the rear-end circuit, and the threat is caused to power devices such AS a rectifier bridge or an IPM module of the rear-end circuit. Whether the rear-end power device is damaged or not depends on the size of the hot ground GND copper-clad area of the PCB and the after-sale installation mode of the PCB, namely the size of the gap between the copper sheet of the PCB and the sheet metal part. Since the magnitude of these two variables influences the resistance value Zr of the hot ground GND to earth (sheet metal part). The impedance Zx between the impedance Zr and the DC bus P-N forms a partial voltage, namely, the partial voltage is carried out on the surge overvoltage running to the rear end circuit. The Zx is parasitic between the dc buses P-N, and thus, the Zx can be controlled by changing, specifically: the Zx is reduced by a fixed resistance R1. When the value of R1 is as small as possible, the self heating of the resistor can be ensured within a safety range without being damaged, and the voltage obtained by Zx division can be ensured within the safety range of the power device to form a first guarantee. When the first guarantee fails, the piezoresistor RV4 acts, so that the Zx dividing voltage cannot exceed the withstand voltage limit value of a rectifier bridge or an IPM of the power device, and the power device is protected from being damaged.

Example two, as shown in fig. 2.

The second embodiment is basically the same as the first embodiment in structure, and the main difference is that the external ac power supply of the second embodiment is a three-phase power supply, which includes a phase line L1, a phase line L2, a phase line L3, a neutral line N, and a ground PE.

Correspondingly, the surge suppression loop comprises the following connections: a voltage dependent resistor RV1 is arranged between the phase line L3 and the zero line N; a voltage dependent resistor RV2 is arranged between the phase line L2 and the zero line N; a voltage dependent resistor RV3 is arranged between the phase line L1 and the zero line N; a discharge tube AS1 is arranged between the neutral line N and the ground PE.

Correspondingly, the rectifier bridge is formed by connecting diodes D1, D2, D3, D4, D5 and D6 in series.

The working process of the second embodiment is basically the same as that of the first embodiment.

The utility model discloses the part that does not relate to all is the same with prior art or can adopt prior art to realize.

Claims

1. A common-mode surge voltage impact resistance circuit of an air conditioner variable frequency controller comprises a rectifier bridge, a rectifier bridge and a rectifier bridge, wherein an external alternating current power supply is rectified to form a direct current bus P-N; the direct current bus P-N is connected with a power device of the controller; the surge suppression circuit is characterized in that a surge suppression circuit is arranged between the external alternating current power supply and the rectifier bridge; and a voltage clamping device and a resistor R1 are arranged between the direct current buses P-N.

2. The circuit of claim 1, wherein the external ac power source is a single-phase power source including a phase line, a neutral line and a ground; the surge suppression loop comprises the following connections: a voltage dependent resistor RV1 is arranged between the phase line and the zero line, and the phase line is connected to the ground after passing through a voltage dependent resistor RV3 and a discharge tube; the neutral wire is connected to the ground after passing through a piezoresistor RV2 and the discharge tube.

3. The circuit of claim 1, wherein the external ac power source is a three-phase power source including a phase line L1, a phase line L2, a phase line L3, a neutral line and a ground; the surge suppression loop comprises the following connections: phase line L3 with be equipped with piezo-resistor RV1 between the zero line, phase line L2 with be equipped with piezo-resistor RV2 between the zero line, phase line L1 with be equipped with piezo-resistor RV3 between the zero line, the zero line with be equipped with discharge tube between the earth.

4. The circuit of claim 1, wherein the voltage-clamping device is a TVS diode or a varistor RV 4.

5. The circuit of claim 2 or 3, wherein the discharge tube is a gas discharge tube.

6. The circuit of claim 1, wherein the resistor R1 is a fixed resistor.

7. The circuit of claim 1, wherein a capacitor E1 is disposed between the dc buses P-N.