Reactive aging test circuit

Abstract

The invention relates to an aging test technology, in particular to a reactive aging test circuit. The aging test module comprises a test device and a test unit, and the test unit is connected with the test device and used for performing aging test on the test device; the test unit comprises a power supply, a control panel and a busbar unit; the power supply is used for supplying power to the control panel, the busbar unit and the test device; the control panel generates a test signal for testing the test device and generates a control signal for controlling the power supply; the busbar unit is used for connecting a control board and a test device. According to the test device designed by the invention, the stray inductance of the test device is reduced, the switch peak voltage Vdspeak is reduced, the voltage stress Vds switching speed dV / dt and the current stress switching speed di / dt of the power module are improved, and an aging test circuit is enabled to be more suitable for a client use environment.

Description

Technical Field

[0001] The invention relates to aging test technology, in particular to a reactive aging test circuit. Background Art

[0002] In recent years, reactive power aging testing has become a key step in evaluating the lifespan and performance stability of power electronic devices (such as IGBT modules, capacitors, and reactors). Traditional reactive power aging testing equipment typically applies a continuous reactive load to the device under test using an external power supply, simulating the reactive power impacts found in actual operating conditions.

[0003] Existing technical solutions such as CN201510288357.8 mostly use resistive loads or linear power supplies for direct loading, which have the following defects: Reactive power is dissipated through resistors or linear power supplies, converting electrical energy into heat during testing. This results in low energy efficiency (typical losses reach 60%-80%), significantly increasing testing costs and requiring additional heat dissipation equipment. Traditional busbar designs fail to account for the effects of stray inductance and distributed capacitance, which can easily cause voltage oscillations under high-frequency conditions, leading to test waveform distortion (e.g., harmonic distortion exceeding ±5%) and compromising the accuracy of aging assessments.

[0004] During the test, inrush current and voltage spikes can easily damage the device under test and the control circuit. However, existing technologies lack effective polarity protection and dynamic energy discharge mechanisms, resulting in an increased equipment failure rate. Summary of the Invention

[0005] The present invention provides a reactive aging test circuit to address the problem that traditional busbar designs in the prior art fail to consider the influence of stray inductance and distributed capacitance, which easily induces voltage oscillation under high-frequency conditions, leading to test waveform distortion (such as harmonic distortion of more than ±5%), and affecting the accuracy of aging assessment.

[0006] In order to solve the above technical problems, the present invention is solved by the following technical solutions: A reactive power aging test circuit includes a test device and a test unit. The test unit is connected to the test device and is used to perform an aging test on the test device. The test unit includes a power supply, a control board and a busbar unit. The power supply is used to provide power to the control board, the busbar unit and the test device. The control board generates a test signal for testing the test device and generates a control signal to control the power supply. The busbar unit is used to connect the control board and the test device.

[0007] Preferably, a diode protection unit is further included, one end of the diode protection unit is connected to the power supply, and the other end is connected to the control board, and the control board is protected by the diode protection unit.

[0008] Preferably, a filter capacitor unit is further included, and the filter capacitor unit is connected in parallel with the busbar unit and the test component.

[0009] Preferably, one end of the busbar unit is also connected to a bus capacitor, the other end of the test assembly is connected to a reactor, and the reactor and the bus capacitor are cyclically charged and discharged.

[0010] Preferably, the control board includes a MOSFET Q1, a resistor unit and a MOSFET Q2; the MOSFET Q1, the resistor unit and the MOSFET Q2 are connected in series with each other; the second port of the MOSFET Q1 is connected to the diode protection unit and the bus capacitor, and the third port of the MOSFET Q2 is connected to the power supply and the bus capacitor.

[0011] The present invention has the following significant technical effects due to the adoption of the above technical solution: The reactive power aging test device designed in the present invention reduces the noise inductance of the test device, reduces the switching peak voltage Vds_peak, improves the voltage stress Vds switching speed dV / dt and the current stress switching speed di / dt of the power module, and makes the aging test circuit more suitable for the customer's usage environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a circuit principle diagram of the present invention.

[0013] Figure 2 This is a circuit diagram of embodiment 1 of the present invention.

[0014] Figure 3 It is a control circuit diagram of the control board of the present invention. DETAILED DESCRIPTION

[0015] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0016] Example 1

[0017] A reactive power aging test circuit includes a test device and a test unit. The test unit is connected to the test device and is used to perform an aging test on the test device. The test unit includes a power supply, a control board and a busbar unit. The power supply is used to provide power to the control board, the busbar unit and the test device. The control board generates a test signal for testing the test device and generates a control signal to control the power supply. The busbar unit is used to connect the control board and the test device.

[0018] One end of the busbar unit is also connected to a bus capacitor, and the other end of the test assembly is connected to a reactor, which cyclically charges and discharges with the bus capacitor. The control board includes a MOSFET Q1, a resistor unit, and a MOSFET Q2; MOSFET Q1, the resistor unit, and MOSFET Q2 are connected in series. The second port of MOSFET Q1 is connected to the diode protection unit and the bus capacitor, and the third port of MOSFET Q2 is connected to the power supply and the bus capacitor.

[0019] The MOS tube Q1 switch controls the opening and closing of the test power supply, and cuts off the power supply when an alarm occurs to prevent long-term high-power power supply; when the MOS tube Q2 finishes aging, it provides rapid discharge of the bus capacitor to prevent high voltage from existing on the device.

[0020] For the bus capacitor, it provides short-time high-current discharge. The reactor has a certain impedance and energy storage, and performs cyclic charging and discharging together with the bus capacitor.

[0021] Example 2

[0022] A reactive power aging test circuit comprises a test device and a test unit, wherein the test unit is connected to the test device and is used to perform an aging test on the test device; the test unit comprises a power supply, a control board and a busbar unit; the power supply is used to provide power to the control board, the busbar unit and the test device; the control board generates a test signal for testing the test device and generates a control signal for controlling the power supply; the busbar unit is used to connect the control board and the test device, and also comprises a diode protection unit, one end of the diode protection unit is connected to the power supply and the other end is connected to the control board, and the control board is protected by the diode protection unit.

[0023] One end of the busbar unit is also connected to a bus capacitor, and the other end of the test assembly is connected to a reactor. The reactor and the bus capacitor are cyclically charged and discharged. The control board includes a MOSFET Q1, a resistor unit, and a MOSFET Q2. MOSFET Q1, the resistor unit, and the MOSFET Q2 are connected in series. The second port of MOSFET Q1 is connected to the diode protection unit and the bus capacitor, and the third port of MOSFET Q2 is connected to the power supply and the bus capacitor. The diodes used are unidirectional diodes; these unidirectional diodes ensure that the power supply is unidirectional, thereby protecting the control board from high currents.

[0024] Example 3

[0025] A reactive power aging test circuit includes a test device and a test unit. The test unit is connected to the test device and is used to perform an aging test on the test device. The test unit includes a power supply, a control board, and a busbar unit. The power supply is used to provide power to the control board, the busbar unit, and the test device. The control board generates a test signal for testing the test device and generates a control signal to control the power supply. The busbar unit is used to connect the control board and the test device. The busbar unit also includes a diode protection unit, one end of which is connected to the power supply and the other end to the control board, and protects the control board through the diode protection unit. The busbar unit also includes a filter capacitor unit, which is connected in parallel with the busbar unit and the test assembly. The filter capacitor unit reduces inductance, improves the voltage stress Vds switching speed dV / dt of the power module, and improves the current stress switching speed di / dt, making the aging test circuit more suitable for customer usage environments.

[0026] One end of the busbar unit is also connected to a bus capacitor, and the other end of the test assembly is connected to a reactor, which cyclically charges and discharges with the bus capacitor. The control board includes a MOSFET Q1, a resistor unit, and a MOSFET Q2; MOSFET Q1, the resistor unit, and MOSFET Q2 are connected in series. The second port of MOSFET Q1 is connected to the diode protection unit and the bus capacitor, and the third port of MOSFET Q2 is connected to the power supply and the bus capacitor.

[0027] Example 4

[0028] Based on the above embodiment, this embodiment welds a filter capacitor unit onto the test fixture. The filter capacitor unit is an independent small capacitor. The filter capacitor unit is a non-inductive, low-ESR, high-voltage capacitor suitable for rapid charge and discharge. During the test process, it can provide a large instantaneous current and effectively absorb spike voltages.

[0029] The power supply is a busbar test power supply. The positive terminal of the busbar test power supply, PS+, is connected to the positive terminal of a unidirectional diode, the negative terminal of which is connected to the input terminal of the control board. After passing through the control board's switching tube, the output from the control board's input terminal is connected to one terminal of the busbar capacitor. The other end of the busbar capacitor is then connected to the busbar unit, which is a laminated busbar. The middle connection of the laminated busbar is a soft-connected kilo-layer copper, which provides a certain amount of floating displacement. The soft-connected kilo-layer copper is not hard-pressed. Blind holes are drilled at the appropriate hard-pressed locations on the bottom of the kilo-layer copper, and a set of non-inductive, low-ESR, high-voltage capacitors are soldered to these blind holes. The power terminals PN of the power device are assembled on the kilo-layer copper hard-pressed blocks. The U, V, and W terminals of the power device are connected to three sets of reactors, respectively. The other ends of the three reactors are short-circuited using large copper blocks.

Claims

1. A reactive aging test circuit, comprising a test device and a test unit, wherein the test unit is connected to the test device and is used to perform an aging test on the test device; characterized in that: The test unit includes a power supply, a control board and a busbar unit; the power supply is used to provide power to the control board, the busbar unit and the test device; the control board generates a test signal for testing the test device and generates a control signal to control the power supply; the busbar unit is used to connect the control board and the test device.

2. A reactive aging test circuit according to claim 1, characterized in that: It also includes a diode protection unit, one end of the diode protection unit is connected to the power supply, and the other end is connected to the control board, and the control board is protected by the diode protection unit.

3. A reactive aging test circuit according to claim 1, characterized in that: It also includes a filter capacitor unit, which is connected in parallel with the busbar unit and the test component.

4. A reactive aging test circuit according to claim 1, characterized in that: One end of the busbar unit is also connected to a bus capacitor, and the other end of the test component is connected to a reactor, and the reactor and the bus capacitor are cyclically charged and discharged.

5. A reactive aging test circuit according to claim 1, characterized in that: The control board includes a MOSFET Q1, a resistor unit and a MOSFET Q2; the MOSFET Q1, the resistor unit and the MOSFET Q2 are connected in series; the second port of the MOSFET Q1 is connected to the diode protection unit and the bus capacitor, and the third port of the MOSFET Q2 is connected to the power supply and the bus capacitor.

Images