HMCJ-400kV/20kJ Lightning Impulse Voltage Generator: Technical Overview
I. What Is a Lightning Impulse Voltage Generator?
A lightning impulse voltage generator is a power supply device designed to simulate impulse voltages such as lightning and operational overvoltages; it is essential equipment in high-voltage testing laboratories. It is primarily used to conduct impulse voltage tests-including full-wave lightning impulse voltage, truncated lightning impulse voltage, and operational impulse voltage-on test specimens such as power equipment to evaluate their insulation performance.
This equipment employs a Marx circuit to implement the working principle of "multi-stage capacitor parallel charging and series discharging," thereby "amplifying" a lower voltage into a pulse voltage of extremely high amplitude to simulate the waveform and peak values of actual lightning. According to the provisions of the international standard IEC 60060-1 and the national standard GB/T 16927, the standard lightning impulse waveform parameters are 1.2/50 μs, i.e., a unipolar double-exponential curve with a rise time of approximately 1.2 microseconds and a half-peak duration of approximately 50 microseconds.
II. Why Conduct Lightning Impulse Tests?
Before high-voltage electrical equipment in power systems is put into operation, it must undergo surge voltage testing to verify its insulation performance under overvoltage conditions. The reason is simple: while the voltage equipment experiences during normal operation is not high, a lightning strike or grid switching operation can instantly generate overvoltages that are tens or even hundreds of times higher than normal voltage. Surge withstand voltage testing is conducted to verify whether the equipment can still "hold up" under such extreme conditions, thereby ensuring the safe and stable operation of the power grid.
III. An Explanation of the HMCJ-400kV/20kJ
The HMCJ-400kV/20kJ lightning impulse voltage generator is a flagship product launched by Goldhome to meet the insulation testing needs of medium- and high-voltage equipment. "400kV" represents the device's maximum output impulse voltage, while "20kJ" represents its rated energy storage capacity. The device features a four-stage epoxy pillar tower integrated structure, with each stage capable of ±100 kV. The overall design is compact and space-efficient.
The device employs a Marx circuit architecture: charging resistors are used to charge the capacitors in each stage in parallel to the set voltage, after which a spark gap triggers a series discharge, generating a high-voltage impulse wave on the load capacitor. The system can stably generate various waveforms, including standard lightning impulse full-wave (1.2/50 μs), lightning impulse truncated wave (2–6 μs), and standard operational impulse (250/2500 μs). When the load capacitance is 300–1000 pF, the voltage utilization factor is no less than 1.2, fully complying with the requirements of IEC and GB/T 16927 standards. The equipment is also equipped with a constant-current charging automatic control system, with a charging accuracy of ≤1%, supporting stepless adjustment from 10% to 100% of the rated voltage.
IV. Introduction to Goldhome
Wuhan Goldhome Hipot Electrical Co., Ltd. was established in 2008 and is located in the Wuhan Economic and Technological Development Zone. It is a national high-tech enterprise and a provincial-level "Specialized, Refined, Unique, and Innovative" (SRUI) "Little Giant" enterprise. With over 10,000 square meters of modern production facilities, the company has dedicated more than two decades to the R&D and manufacturing of high-voltage testing equipment. Its product portfolio spans multiple fields, including AC resonance test systems, AC/DC withstand voltage testers, partial discharge detection systems, and surge voltage/current generators. Strictly adhering to international standards such as IEC and IEEE, the company's products have been successfully exported to over 30 countries and regions, including Germany, the United States, Italy, and Vietnam, with a cumulative global installation base exceeding 100,000 units.
V. Conclusion
Lightning impulse voltage generators are not only core equipment in high-voltage laboratories but also the "unsung heroes" safeguarding power grid security. From factory acceptance testing to grid operation and maintenance, every impulse test adds an extra layer of protection to our electrical safety. Through continuous technological innovation and reliable equipment quality, Goldhome is contributing to the safe operation of power systems worldwide.
