Power unit test tool

Abstract

The utility model discloses a power unit test tool, which comprises a soft start power supply circuit, an output filter circuit, a main control box and a display part, the input end of the soft start power supply circuit is connected with an AC power supply, and the output end of the soft start power supply circuit is connected with the input end of a to-be-tested power unit. The output filter circuit is connected with the output end of the to-be-tested power unit so as to filter the output voltage of the to-be-tested power unit; the main control box is connected with the soft start power supply circuit, the output filter circuit and the to-be-tested power unit; the main control box is used for controlling the soft start power supply circuit to provide required input voltage for the to-be-tested power unit and driving the to-be-tested power unit to operate, and collecting output voltage of the to-be-tested power unit through the output filter circuit; and the display part is connected with the main control box so as to display the output voltage acquired by the main control box. According to the invention, testing of power units with different capacities can be realized, and the tool is convenient to carry and simple to operate.

Description

Technical Field

[0001] The present application relates to the technical field of frequency converters, and in particular to a power unit testing tool. Background Art

[0002] With the widespread application of cascade inverters, inverters of various capacities have been vigorously developed, the capacity of power units has also become diverse, and the maintenance and detection of power units have become particularly important.

[0003] The common detection method now is: supply driving power to the power unit, then send the wave command through software configuration, and finally observe the output voltage waveform to determine whether the power unit is normal. However, this method has some disadvantages: 1. The rectifier part is not tested; 2. Software configuration requires professionals, which is easy to make mistakes for non-professionals; 3. There are many detection equipments, which are not easy to carry and transport. Utility Model Content

[0004] The present application provides a power unit testing tool to implement testing of power units of different capacities.

[0005] The present application provides a power unit test fixture, including a soft-start power supply circuit, an output filter circuit, a main control box and a display part;

[0006] The input end of the soft-start power supply circuit is connected to an AC power supply, and the output end of the soft-start power supply circuit is connected to an input end of a power unit to be tested;

[0007] The output filter circuit is connected to the output end of the power unit to be tested to filter the output voltage of the power unit to be tested;

[0008] The main control box is connected to the soft-start power supply circuit, the output filter circuit and the power unit to be tested; the main control box is used to control the soft-start power supply circuit to provide the required input voltage for the power unit to be tested and drive the power unit to be tested to operate, and collect the output voltage of the power unit to be tested through the output filter circuit;

[0009] The display part is connected to the main control box to display the output voltage collected by the main control box.

[0010] In one example, the soft-start power supply circuit includes an input switch, a pre-charging circuit and a transformer connected in sequence; wherein the input end of the input switch is connected to an AC power supply, and the secondary side of the transformer is connected to the input end of the power unit to be tested.

[0011] In one example, the pre-charging circuit includes a pre-charging resistor and a pre-charging switch connected in parallel.

[0012] In one example, the pre-charge switch includes a contactor.

[0013] In one example, the output filter circuit includes a first filter resistor, a second filter resistor, and a first filter capacitor. The first filter resistor is connected in parallel with the first filter capacitor and then connected in series with the second filter resistor.

[0014] In one example, the output filter circuit includes a third filter resistor, a filter inductor, and a second filter capacitor. The third filter resistor is connected in parallel with the second filter capacitor and then connected in series with the filter inductor.

[0015] In one example, the main control box includes a main control board, a DO signal board, an optical fiber driving board and a voltage detection board connected to the main control board;

[0016] The DO signal board is used to control the soft-start power supply circuit; the optical fiber driving board is used to drive the power unit to be tested; the voltage detection board is connected to the output filter circuit to collect the output voltage of the power unit to be tested.

[0017] In one example, the display portion is connected to the main control box via an optical fiber.

[0018] In one example, a main control box power supply is further included, which is used to provide power to the main control box.

[0019] In one example, the power unit to be tested includes a diode rectifier circuit, a bus capacitor, and an H-bridge inverter circuit connected in sequence.

[0020] The power unit testing tool provided in the present application can realize the testing of power units of different capacities. The tool is easy to carry and simple to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of a power unit provided in an embodiment of the present application;

[0022] Figure 2 A schematic diagram of a power unit test tool provided in an embodiment of the present application;

[0023] Figure 3 Schematic diagram of the DO signal board provided in an embodiment of the present application.

[0024] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer and more understandable, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0026] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0027] Figure 1 A schematic diagram of a power unit provided in an embodiment of the present application.

[0028] like Figure 1 As shown, the power unit consists of a rectifier part and an inverter part. The rectifier part is a rectifier circuit composed of diodes D1 to D6, and each phase input of the rectifier circuit is connected in series with a fuse. The inverter part includes an H-bridge inverter circuit, which is composed of semiconductor switch tubes Q1 to Q4. Capacitors C1 to C3 are bus capacitors, and resistors R1 to R3 are equalizing resistors. The equalizing resistor R1 is connected in parallel with the bus capacitor C1, the equalizing resistor R2 is connected in parallel with the bus capacitor C2, and the equalizing resistor R3 is connected in parallel with the bus capacitor C3. Z1 is a bypass switch.

[0029] It should be noted that for power units of different capacities, the structures and device models of the rectifier and inverter parts will also change accordingly.

[0030] Figure 2 A schematic diagram of a power unit test tooling provided in an embodiment of the present application.

[0031] like Figure 2 As shown, the power unit test tooling includes a soft-start power supply circuit, an output filter circuit, a main control box, and a display part.

[0032] The input end of the soft-start power supply circuit is connected to an AC power supply, and the output end of the soft-start power supply circuit is connected to an input end of a power unit to be tested;

[0033] The output filter circuit is connected to the output end of the power unit to be tested to filter the output voltage of the power unit to be tested;

[0034] The main control box is connected to the soft-start power supply circuit, the output filter circuit and the power unit to be tested; the main control box is used to control the soft-start power supply circuit to provide the required input voltage for the power unit to be tested and drive the power unit to be tested to operate, and collect the output voltage of the power unit to be tested through the output filter circuit;

[0035] The display part is connected to the main control box to display the output voltage collected by the main control box.

[0036] In one example, the soft-start power supply circuit includes an input switch, a pre-charging circuit and a transformer connected in sequence; wherein the input end of the input switch is connected to an AC power supply, and the secondary side of the transformer is connected to the input end of the power unit to be tested. The pre-charging circuit includes a pre-charging resistor and a pre-charging switch connected in parallel. The pre-charging switch includes a contactor.

[0037] Specifically, the power supply soft start circuit is connected to the input end of the input switch (shown as K1 to K3 in the figure) by a three-phase AC incoming line, the output end of the input switch is connected to the input end of the contactor (shown as SW1 to SW3 in the figure), the pre-charging resistor (shown as R4 to R6 in the figure) is connected in parallel with the contactor, the output end of the contactor is connected to the primary side of the transformer T, the transformer T converts the input voltage into the rated input voltage of the power unit to be tested, and the secondary side of the transformer T is connected to the input end of the power unit to be tested.

[0038] In one example, the output filter circuit includes a first filter resistor, a second filter resistor, and a first filter capacitor. The first filter resistor is connected in parallel with the first filter capacitor and then connected in series with the second filter resistor.

[0039] In one example, the output filter circuit includes a third filter resistor, a filter inductor, and a second filter capacitor. The third filter resistor is connected in parallel with the second filter capacitor and then connected in series with the filter inductor.

[0040] Specifically, the filter resistor r2 is connected in parallel with the filter capacitor c1 and then connected in series with the filter resistor r1, or the filter resistor r1 is replaced with the filter inductor L1 to form an LC filter circuit. The main function of the filter circuit is to filter the output voltage PWM waveform into a smooth sinusoidal waveform to facilitate sampling by the voltage detection board.

[0041] In one example, the main control box includes a main control board, a DO signal board, an optical fiber driving board and a voltage detection board connected to the main control board;

[0042] The DO signal board is used to control the soft-start power supply circuit; the optical fiber driving board is used to drive the power unit to be tested; the voltage detection board is connected to the output filter circuit to collect the output voltage of the power unit to be tested.

[0043] In one example, the display portion is connected to the main control box via an optical fiber.

[0044] In one example, a main control box power supply is further included, which is used to provide power to the main control box.

[0045] Specifically, Figure 3 As shown, in the DO signal board, one end of the closing coil of the contactor (shown as SW1 to SW3 in the figure) is connected to the power supply, for example, the N line of 220v, and the other end is connected to one end of the normally open contact of the relay, and the other end of the normally open contact of the relay is connected to the L line of 220V, and the contacts at both ends of the relay coil are connected to the DO contact port of the DO signal board as the DO command signal. In this way, when the command to close the contactor is given, the relay coil is energized, the normally open contact of the relay is closed, and the closing coil of the contactor is powered by 220V, and then the contactor can be closed, and the indicator light of the relay is on; when the contactor needs to be disconnected, the closing DO command is cancelled, and then the relay coil loses 220V, the normally open contact returns to the normally open state, and the contactor closing coil also loses 220V, and the contactor is opened.

[0046] The display part includes an integrated LCD display screen which communicates with the main control box via optical fiber to display the voltage waveform and system unit status.

[0047] The preferred embodiments of the present application are described above with reference to the accompanying drawings, but the scope of the present application is not limited thereby. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present application shall be within the scope of the present application.

Claims

1. A power unit test tool, characterized in that: It includes soft-start power supply circuit, output filter circuit, main control box and display part; The input end of the soft-start power supply circuit is connected to an AC power supply, and the output end of the soft-start power supply circuit is connected to an input end of a power unit to be tested; The output filter circuit is connected to the output end of the power unit to be tested to filter the output voltage of the power unit to be tested; The main control box is connected to the soft-start power supply circuit, the output filter circuit and the power unit to be tested; the main control box is used to control the soft-start power supply circuit to provide the required input voltage for the power unit to be tested and drive the power unit to be tested to operate, and collect the output voltage of the power unit to be tested through the output filter circuit; The display part is connected to the main control box to display the output voltage collected by the main control box.

2. The power unit test fixture according to claim 1, characterized in that: The soft-start power supply circuit includes an input switch, a pre-charging circuit and a transformer connected in sequence; wherein the input end of the input switch is connected to an AC power supply, and the secondary side of the transformer is connected to the input end of the power unit to be tested.

3. The power unit test fixture according to claim 2, characterized in that: The pre-charging circuit includes a pre-charging resistor and a pre-charging switch connected in parallel.

4. The power unit test fixture according to claim 3, characterized in that: The pre-charge switch includes a contactor.

5. The power unit test fixture according to claim 1, characterized in that: The output filter circuit includes a first filter resistor, a second filter resistor and a first filter capacitor. The first filter resistor is connected in parallel with the first filter capacitor and then connected in series with the second filter resistor.

6. The power unit test fixture according to claim 1, characterized in that: The output filter circuit includes a third filter resistor, a filter inductor and a second filter capacitor. The third filter resistor is connected in parallel with the second filter capacitor and then connected in series with the filter inductor.

7. The power unit test fixture according to claim 1, characterized in that: The main control box includes a main control board, a DO signal board, an optical fiber drive board and a voltage detection board connected to the main control board; The DO signal board is used to control the soft-start power supply circuit; The optical fiber driving board is used to drive the power unit to be tested; the voltage detection board is connected to the output filter circuit to collect the output voltage of the power unit to be tested.

8. The power unit test fixture according to claim 1, characterized in that: The display part is connected to the main control box via an optical fiber.

9. The power unit test fixture according to claim 1, characterized in that: Also included is a main control box power supply, which is used to provide power to the main control box.

10. The power unit test fixture according to claim 1, characterized in that: The power unit to be tested includes a diode rectifier circuit, a bus capacitor and an H-bridge inverter circuit which are connected in sequence.

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