The world’s first dry air-core reactor inter-turn insulation defect detector was ex-works

1,350 kW variable-frequency power supply consisting of three parallel-connected units was ex-works

1,200 kV variable-frequency series resonant test system was ex-works.

The first same frequency and phase high voltage test system for power equipment such as GIS successfully passed the field test

250 kV/30 A high voltage reactor was ex-works

The PD free variable-frequency power supply device was successfully applied in the partial discharge test for the first converter transformer

The first 1,200 kV positive and negative polarity DC generator at high altitudes successfully passed the field test

The PD free variable-frequency power supply device was successfully applied the partial discharge test for the first 1,000 kV UHV transformer

The first three-phase PD free variable-frequency power supply was ex-works

900 kW variable-frequency power supply consisting of two parallel-connected units was ex-works

The PD free variable-frequency power supply device was successfully applied in the partial discharge test for the first 750 kV transformer

Introduced optical fiber remote control into variable-frequency power supply devices

Supplied series resonant devices employing pulse-width modulated variable-frequency power supply

The PD free variable-frequency power supply device was awarded utility model patent

Developed the first push-pull amplified PD free variable-frequency power supply