The series resonance voltage withstand test device is a "core heavy equipment" for AC voltage withstand tests on large high-voltage equipment (such as long cables, large transformers, generators, GIS) in power systems.



Its core value lies in solving a physical problem: how to use lightweight equipment to test heavy equipment with large capacitance and high voltage?

By utilizing the principle of LC series resonance, it can reduce the power capacity requirement to 1/10 to 1/50 of traditional test equipment, achieving "small power output, high voltage", and is currently the mainstream solution for high-voltage withstand tests.

The following is a detailed analysis compiled in accordance with the latest technical standards in 2026 (such as DL/T 849.6-2016, GB 50150-2016):

⚙️ Core Working Principle

Simply put, its working logic is "frequency matching, voltage amplification".

Physical Basis (LC Series Resonance)

The device uses an excitation transformer, reactor (L), and the equipment under test (equivalent to capacitor C) connected in series to form a loop.

By adjusting the output frequency (f) of the variable frequency power supply, the inductive reactance (

Result: The power supply only needs to provide a very small voltage and power (only to compensate for the loop resistance loss), and can generate dozens of times higher voltage on the test object, completing the withstand voltage test.