CN215449532U

CN215449532U - Complete machine open loop test circuit of three-phase three-level PFC circuit

Info

Publication number: CN215449532U
Application number: CN202120745066.9U
Authority: CN
Inventors: 秦惠
Original assignee: Shenzhen Zhenhua Microelectronics Co Ltd
Current assignee: Shenzhen Zhenhua Microelectronics Co Ltd
Priority date: 2021-04-12
Filing date: 2021-04-12
Publication date: 2022-01-07
Anticipated expiration: 2031-04-12

Abstract

The application provides a complete machine open loop test circuit of a three-phase three-level PFC circuit, which is applied to the field of ground aviation systems and is used for testing a circuit, a main circuit and an auxiliary power supply circuit SPS according to the characteristics of the three-phase three-level PFC circuit; the output end of the test circuit is connected with the main circuit, and the output end of the main circuit is connected with an auxiliary power supply circuit (SPS); the test circuit comprises a direct-current power supply, an A-phase switch tube, a B-phase switch tube, a C-phase switch tube, a buffer resistor R1, a buffer resistor R2, a buffer resistor R3 and a relay K1; the open-loop test method is invented, after the test of the whole machine single board is completed and before the closed-loop test of the whole machine is performed, the open-loop test method is inserted into the open-loop test link, the open-loop test is performed on the whole machine main circuit and the control circuit, the fault point is positioned in time and the fault is eliminated, the one-time pass rate of the product is improved, and the maintenance speed in a factory is accelerated; the technical problems that the production of the fryer in a factory of a three-phase three-level PFC circuit is frequent and the repair of the fryer is difficult can be reliably solved.

Description

Complete machine open loop test circuit of three-phase three-level PFC circuit

Technical Field

The application relates to the technical field of ground aviation systems, in particular to a complete machine open-loop test circuit of a three-phase three-level PFC circuit.

Background

The power supply needs to be completely tested and troubleshooting in a factory, the conventional factory processing experience is that rated three-phase voltage is directly input by using a tool, and for a rectifier PFC circuit adopting three levels, if a certain switching tube is short-circuited and fails in the manufacturing process, the whole machine has the risk of machine explosion in the power-on test, so that the finished product rate of the whole machine is reduced;

for the occurrence of the situation, a common test method usually sets 3 circuits with different inputs for one-by-one test, but such a test method often lacks a short-circuit overcurrent protection function or only has a single hardware protection function or a single software protection function, and when a short circuit or an overcurrent occurs in a unit to be tested, short-circuit overcurrent protection cannot be rapidly implemented on the test circuit and the unit to be tested due to a slow response speed, so that the test circuit and the unit to be tested are damaged, and the production efficiency is reduced.

SUMMERY OF THE UTILITY MODEL

The short-circuit overcurrent protection circuit aims to solve the problem that a short-circuit overcurrent protection function is often lacked or only a single hardware protection function or software protection function is provided, short-circuit overcurrent protection cannot be rapidly implemented on a test circuit and a tested unit due to slow response speed when a tested unit is short-circuited or overcurrent, so that the test circuit and the tested unit are damaged, the technical problem of production efficiency is reduced, and the whole open-loop test circuit of the three-phase three-level PFC circuit is provided.

The application adopts the following technical means for solving the technical problems:

a complete machine open loop test circuit of a three-phase three-level PFC circuit comprises a test circuit, a main circuit and an auxiliary power supply circuit (SPS);

the output end of the test circuit is connected with the main circuit, and the output end of the main circuit is connected with an auxiliary power supply circuit (SPS);

the test circuit comprises a direct-current power supply, an A-phase switch tube, a B-phase switch tube, a C-phase switch tube, a buffer resistor R1, a buffer resistor R2, a buffer resistor R3, a relay K1, a relay K2 and a relay K3; the output end of the direct-current power supply is connected to one end of an A-phase switch tube, one end of a B-phase switch tube and one end of a C-phase switch tube respectively, the other ends of the A-phase switch tube, the B-phase switch tube and the C-phase switch tube are connected in series corresponding to the relay K1, the relay K2 and the relay K3 respectively, the relay K1, the relay K2 and the relay K3 are connected in parallel corresponding to the buffer resistor R1, the buffer resistor R2 and the buffer resistor R3 respectively, and the output ends of the relay K1, the relay K2 and the relay K3 are connected with a main circuit;

the main circuit comprises a BUS BUS +, a BUS BUS-, a BUS BUSN, an inductor L1, a triode Q1 and a plurality of diodes; the output ends of the relay K1, the relay K2 and the relay K3 are connected with the inductor L1 in series, the inductor L1 is connected into a triode Q1 and a plurality of diodes in a bridge rectifier circuit, and the bridge rectifier circuit outputs BUS +, BUS BUS and BUS BUSN signals to the auxiliary power supply circuit SPS.

Further, the number of the diodes in the bridge rectifier circuit is 7, and the output direction of the diodes is BUS +.

Further, the direct current power supply is a direct current source instrument for testing.

Furthermore, the interval angle between the A-phase switch tube, the B-phase switch tube and the C-phase switch tube is 120 degrees.

Further, the main circuit also comprises a switch tube driving signal with A phase; gb is a B-phase switching tube driving signal; gc is a C-phase switching tube driving signal, and an A-phase switching tube driving signal is obtained according to ga; gb is a B-phase switching tube driving signal; and gc builds a test platform for the drive signal of the C-phase switch tube.

The application provides a complete machine open loop test circuit of three-phase three-level PFC circuit has following beneficial effect:

aiming at the characteristics of a three-phase three-level PFC circuit, an open-loop test method is invented, after the test of a single board of the whole machine is completed and before the closed-loop test of the whole machine is performed, the open-loop test method is inserted into an open-loop test link, the whole main circuit and a control circuit are subjected to open-loop test, fault points are timely positioned and faults are eliminated, the one-time passing rate of a product is improved, and the maintenance speed in a factory is accelerated; the technical problems that the production of the fryer in a factory of a three-phase three-level PFC circuit is frequent and the repair of the fryer is difficult can be reliably solved.

Drawings

Fig. 1 is a circuit diagram of an embodiment of a complete machine open loop test circuit of a three-phase three-level PFC circuit according to the present application;

fig. 2 is a bar chart of a test platform according to an embodiment of a complete machine open loop test circuit of the three-phase three-level PFC circuit of the present application.

The implementation, functional features and advantages of the present application will be further explained with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It is noted that the terms "comprises," "comprising," and "having" and any variations thereof in the description and claims of this application and the drawings described above are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus. In the claims, the description and the drawings of the specification of the present application, relational terms such as "first" and "second", and the like, may be used solely to distinguish one entity/action/object from another entity/action/object without necessarily requiring or implying any actual such relationship or order between such entities/actions/objects.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

Referring to fig. 1-2, a circuit diagram of a complete machine open loop test circuit of a three-phase three-level PFC circuit according to an embodiment of the present application is shown;

Preferably, the number of the diodes in the bridge rectifier circuit is 7, and the output direction of the diodes is BUS +.

Preferably, the dc power supply is a dc power supply instrument for testing.

Preferably, the interval angle among the A-phase switch tube, the B-phase switch tube and the C-phase switch tube is 120 degrees.

Specifically, an open-loop test link and an open-loop test program are set for a three-phase three-level PFC rectification circuit; the ABC three-phase switch tubes are respectively driven at a fixed duty ratio of about 5% -30% by staggering 120 degrees, and the auxiliary power supply immediately runs an open-loop program after being normal;

in the testing process, the original input ABC three-phase high-voltage three-phase power is changed into input between any two phases by using a direct current source, 2 phases are tested once, ABC three phases are tested twice, and the direct current source input overcurrent protection is more sensitive and more timely than the AC alternating current source;

the input voltage of the direct current source is slightly higher than the lowest starting voltage of the auxiliary power supply, and the lowest starting voltage of the auxiliary power supply is far lower than the withstand voltage of the switching tube;

the voltage of the direct current bus output by the open loop is reduced through the self-consumption of the auxiliary power supply, so that the direct current bus is prevented from being rushed up to be overvoltage;

the starting buffer resistor is a current-limiting resistor, and when a rear-stage circuit is short-circuited, the voltage division of the buffer circuit is improved, so that the voltage of an output bus is reduced, the auxiliary power supply is not started due to undervoltage, and the damage and the expansion are prevented.

In one embodiment, the main circuit further comprises a switching tube driving signal with a phase a; gb is a B-phase switching tube driving signal; gc is a C-phase switching tube driving signal, and an A-phase switching tube driving signal is obtained according to ga; gb is a B-phase switching tube driving signal; and gc builds a test platform for the drive signal of the C-phase switch tube. Specifically, open loop test specifications and standards are set for different power supply products.

Although embodiments of the present application 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 application, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A complete machine open loop test circuit of a three-phase three-level PFC circuit is characterized by comprising a test circuit, a main circuit and an auxiliary power supply circuit SPS;

2. The overall open-loop test circuit of the three-phase three-level PFC circuit of claim 1, wherein the number of diodes in the bridge rectifier circuit is 7, and the output direction of the diodes is BUS +.

3. The overall open-loop test circuit of the three-phase three-level PFC circuit of claim 1, wherein the DC power supply is a DC power supply instrument for testing.

4. The overall open-loop test circuit of the three-phase three-level PFC circuit of claim 1, wherein an interval angle between the A-phase switch tube, the B-phase switch tube and the C-phase switch tube is 120 degrees.

5. The overall open-loop test circuit of the three-phase three-level PFC circuit of claim 1, wherein the main circuit further comprises a switching tube driving signal for A phase; gb is a B-phase switching tube driving signal; gc is a C-phase switching tube driving signal, and an A-phase switching tube driving signal is obtained according to ga; gb is a B-phase switching tube driving signal; and gc builds a test platform for the drive signal of the C-phase switch tube.