Durability test circuit for high-power capacitor

Abstract

The utility model discloses a durability test circuit for a high-power capacitor, which particularly relates to the technical field of power electronics and comprises an alternating-current power amplifier, an input power transformer, an output power transformer, a direct-current power supply, a resistor, a first capacitor, a second capacitor and a monitoring circuit. According to the utility model, a plurality of input power transformers are connected in series to test the durability of a capacitor by a plurality of power amplifiers, the circuit is also provided with a monitoring circuit to monitor the working state of the capacitor in real time, the circuit design is optimized, the output power range of the circuit is improved, the circuit is suitable for high-power application scenarios, and the service life of the circuit is prolonged. The capacitor durability test circuit is simple in structure, can meet the durability test requirements of different capacitors under different frequencies, provides an effective solution for the durability test of the capacitors, ensures the stable operation of the capacitors under various conditions, and improves the quality and reliability of products.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, and more specifically, to a durability test circuit for a high-power capacitor. Background Art

[0002] With the continuous advancement of power electronics technology, DC support capacitors are increasingly used in the power electronics industry, such as flexible DC transmission, photovoltaic inverters, wind power converters, high-voltage inverters and other fields. These capacitors need to withstand DC voltage and AC current of different frequencies and operate stably in high temperature and high humidity environments.

[0003] However, in actual operation, capacitors may face various challenges, such as voltage and current fluctuations, changes in environmental conditions, etc. In order to ensure the performance stability and life reliability of capacitors, durability testing has become an important link. The durability test circuit is used to simulate the working conditions of capacitors in actual use in order to evaluate their performance and life.

[0004] The durability test circuit usually includes high-voltage power supply, capacitor, load resistor, switch and metering instrument. By applying a certain voltage and current, it simulates the voltage stress and load conditions of the capacitor in actual use. At the same time, it measures and records the current, voltage, power and other parameters in the circuit to evaluate the durability performance of the capacitor.

[0005] However, there are still some shortcomings in actual use. For example, the output power range of the existing durability test circuit for capacitors is too small, which limits the test circuit's ability to test high-power capacitors, making these circuits unsuitable for high-power application scenarios and unable to adapt to the durability test requirements of different capacitors at different frequencies. Utility Model Content

[0006] In order to overcome the above defects of the prior art, an embodiment of the utility model provides a high-power capacitor durability test circuit, which solves the problems raised in the above background technology through the following scheme.

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a high-power capacitor durability test circuit, including: AC power amplifier U1, AC power amplifier U2...AC power amplifier Un, input power transformer L1, input power transformer L2...input power transformer Ln, output power transformer Lo, DC power supply E, resistor R1, capacitor C1, capacitor C2, and monitoring circuit J1.

[0008] Preferably, the first port and the second port of the primary winding of the input power transformer L1 are connected to the AC power amplifier U1, the first port and the second port of the primary winding of the input power transformer L2 are connected to the AC power amplifier U2, the third port of the secondary winding of the input power transformer L1 is connected in series with the fourth port of the secondary winding of the input power transformer L2, and are connected in turn to the fourth port of the secondary winding of the AC power amplifier Un.

[0009] Preferably, the fourth port of the secondary winding of the input power transformer L1 is connected in series with the first port of the primary winding of the output power transformer Lo, the third port of the secondary winding of the input power transformer Ln is connected in series with the first port of the primary winding of the output power transformer Lo, the fourth port of the secondary winding of the output power transformer Lo is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to one end of the resistor R1 and one end of the capacitor C2, the other end of the capacitor C2 is connected to the third port of the secondary winding of the output power transformer Lo, the center point of the secondary winding of the power transformer Lo is connected to the positive electrode of the DC power supply E, and the negative electrode of the DC power supply E is connected to the other end of the resistor R1.

[0010] Preferably, one end of the monitoring circuit J1 is connected to the positive electrode of the DC power supply E, and the other end is connected to the negative electrode of the DC power supply E.

[0011] Technical effects and advantages of the utility model:

[0012] When the circuit of the utility model starts to operate, the AC power amplifier starts to work and generates an AC signal, which is then input into the primary winding of the corresponding input power transformer. The design of the input power transformer enables it to transform these AC signals to meet the needs of subsequent circuits. The AC signals after the transformation are output from the secondary winding of the input power transformer and connected together in series. These series-connected secondary windings transmit the signal to the primary winding of the output power transformer. The output power transformer further transforms the signal and transmits it to the secondary winding. In the secondary winding of the output power transformer, the signal is divided into two paths, one path is connected to one end of the first capacitor, and the other path is connected to one end of the second capacitor. At the same time, the other end of the first capacitor is connected to one end of the resistor, and the other end of the second capacitor is connected back to the other end of the secondary winding of the output power transformer. The first capacitor and the second capacitor are connected to each other. The two capacitors form a capacitor group, which is used to simulate the capacitors in actual use. The positive pole of the DC power supply is connected to the center point of the secondary winding of the output power transformer, and the negative pole is connected to the other end of the first resistor. The DC power supply provides a stable DC voltage for the circuit to simulate the DC voltage environment of the capacitor in actual use. The monitoring circuit is connected between the positive and negative poles of the DC power supply and is used to monitor the current, voltage, power and other parameters in the circuit in real time. These parameters are important bases for evaluating the durability of the capacitor. During the operation of the circuit, the AC signal generated by the AC power amplifier is transformed through the input power transformer and the output power transformer to form a test signal suitable for the capacitor group. These test signals generate current and voltage in the capacitor group to simulate the working state of the capacitor in actual use. At the same time, the monitoring circuit continuously monitors and records the parameter changes in the circuit for subsequent evaluation of the performance and life of the capacitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the utility model. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0015] refer to Figure 1A high-power capacitor durability test circuit shown in the figure includes AC power amplifier U1, AC power amplifier U2...AC power amplifier Un, input power transformer L1, input power transformer L2...input power transformer Ln, output power transformer Lo, DC power supply E, resistor R1, capacitor C1, capacitor C2, and monitoring circuit J1.

[0016] The first port and the second port of the primary winding of the input power transformer L1 are connected to the AC power amplifier U1, the first port and the second port of the primary winding of the input power transformer L2 are connected to the AC power amplifier U2, the third port of the secondary winding of the input power transformer L1 is connected in series with the fourth port of the secondary winding of the input power transformer L2, and are connected in turn to the fourth port of the secondary winding of the AC power amplifier Un.

[0017] The fourth port of the secondary winding of the input power transformer L1 is connected in series with the first port of the primary winding of the output power transformer Lo, the third port of the secondary winding of the input power transformer Ln is connected in series with the first port of the primary winding of the output power transformer Lo, the fourth port of the secondary winding of the output power transformer Lo is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to one end of the resistor R1 and one end of the capacitor C2, the other end of the capacitor C2 is connected to the third port of the secondary winding of the output power transformer Lo, the center point of the secondary winding of the power transformer Lo is connected to the positive electrode of the DC power supply E, and the negative electrode of the DC power supply E is connected to the other end of the resistor R1.

[0018] One end of the monitoring circuit J1 is connected to the positive electrode of the DC power source E, and the other end is connected to the negative electrode of the DC power source E.

[0019] When the circuit of the utility model starts to operate, the AC power amplifier starts to work and generates an AC signal, which is then input into the primary winding of the corresponding input power transformer. The design of the input power transformer enables it to transform these AC signals to meet the needs of subsequent circuits. The AC signals after the transformation are output from the secondary winding of the input power transformer and connected together in series. These series-connected secondary windings transmit the signal to the primary winding of the output power transformer. The output power transformer further transforms the signal and transmits it to the secondary winding. In the secondary winding of the output power transformer, the signal is divided into two paths, one path is connected to one end of the first capacitor, and the other path is connected to one end of the second capacitor. At the same time, the other end of the first capacitor is connected to one end of the resistor, and the other end of the second capacitor is connected back to the other end of the secondary winding of the output power transformer. The first capacitor and the second capacitor are connected to each other. The two capacitors form a capacitor group, which is used to simulate the capacitors in actual use. The positive pole of the DC power supply is connected to the center point of the secondary winding of the output power transformer, and the negative pole is connected to the other end of the first resistor. The DC power supply provides a stable DC voltage for the circuit to simulate the DC voltage environment of the capacitor in actual use. The monitoring circuit is connected between the positive and negative poles of the DC power supply and is used to monitor the current, voltage, power and other parameters in the circuit in real time. These parameters are important bases for evaluating the durability of the capacitor. During the operation of the circuit, the AC signal generated by the AC power amplifier is transformed through the input power transformer and the output power transformer to form a test signal suitable for the capacitor group. These test signals generate current and voltage in the capacitor group to simulate the working state of the capacitor in actual use. At the same time, the monitoring circuit continuously monitors and records the parameter changes in the circuit for subsequent evaluation of the performance and life of the capacitor.

[0020] Secondly: In the drawings of the embodiments disclosed in the present utility model, only the structures related to the embodiments disclosed in the present utility model are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present utility model can be combined with each other;

[0021] Finally: The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present utility model should be included in the protection scope of the present utility model.

Claims

1. A high-power capacitor durability test circuit, characterized in that: include: Including AC power amplifier U1, AC power amplifier U2...AC power amplifier Un, input power transformer L1, input power transformer L2...input power transformer Ln, output power transformer Lo, DC power supply E, resistor R1, capacitor C1, capacitor C2, and monitoring circuit J1; The first port and the second port of the primary winding of the input power transformer L1 are connected to the AC power amplifier U1, the first port and the second port of the primary winding of the input power transformer L2 are connected to the AC power amplifier U2, the third port of the secondary winding of the input power transformer L1 is connected in series with the fourth port of the secondary winding of the input power transformer L2, and are connected in sequence to the fourth port of the secondary winding of the AC power amplifier Un; The fourth port of the secondary winding of the input power transformer L1 is connected in series with the first port of the primary winding of the output power transformer Lo, the third port of the secondary winding of the input power transformer Ln is connected in series with the first port of the primary winding of the output power transformer Lo, the fourth port of the secondary winding of the output power transformer Lo is connected to one end of the capacitor C1, the other end of the capacitor C1 is connected to one end of the resistor R1 and one end of the capacitor C2, the other end of the capacitor C2 is connected to the third port of the secondary winding of the output power transformer Lo, the center point of the secondary winding of the power transformer Lo is connected to the positive electrode of the DC power supply E, and the negative electrode of the DC power supply E is connected to the other end of the resistor R1; One end of the monitoring circuit J1 is connected to the positive electrode of the DC power source E, and the other end is connected to the negative electrode of the DC power source E.

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