Ultra-low Frequency High Voltage Generator is a special equipment used in power systems for insulation withstand voltage testing of large capacitive test objects (such as long cables, large generators, transformers).



Its core value lies in "achieving big results with small means": by utilizing the physical principle of frequency reduction, it reduces the volume and weight of traditional power frequency (50Hz) withstand voltage equipment by hundreds of times, making it portable and feasible to conduct withstand voltage tests on long-distance cables or large motors on site.

The following is a detailed technical analysis, application scenarios, and operating specifications of this equipment:

⚙️ Core Working Principle

The working logic of the ultra-low frequency high voltage generator can be summarized as "frequency conversion and voltage reduction, achieving big results with small means".

Physical Principle (Why reduce frequency?)

For capacitive loads such as cables and generators, the required test power supply capacity 

When the frequency is reduced from power frequency 50Hz to ultra-low frequency 0.1Hz, the required power supply capacity theoretically drops to 1/500 of the original.

Result: Originally requiring a test transformer weighing several tons, now only a portable device weighing dozens of kilograms is needed to complete the same withstand voltage test.

Circuit Implementation (Three-stage energy conversion)

The equipment typically undergoes three stages of energy conversion internally:

Rectification: Converts the input mains power (AC 220V/380V) into stable DC power.

Inversion and frequency conversion: Uses IGBT or MOSFET inverters to convert DC power into high-frequency square waves, then through low-frequency filtering or digital synthesis technology (DDS), generates ultra-low frequency AC signals of 0.1Hz (or 0.05Hz/0.02Hz).

Voltage boosting: Through a specially designed step-up transformer (typically using nanocrystalline or amorphous alloy cores), the voltage is increased to the high voltage required for the test (e.g., 30kV~90kV).