On-site AC Dielectric Test of UHV Reactors

Abstract: The AC dielectric test is the most direct and effective method to examine the insulation performance of electric equipment. The paper presents an AC dielectric test, which is conducted at 1000kV Nanyang station for UHV reactors via the method of series resonance. The test frequency can be limited within the range of 45-65Hz by proper combination of compensation capacitors and reactors. The test needs less equipment and lower power capacity, which is suitable for on-site AC dielectric test. 

Key words: UHV, reactor, AC dielectric test     

Both GB 50150-2006 Electric Equipment Installation Engineering - Standard for Hand-Over Test of Electric Equipment and DL/T 596-1996 Preventive Test Code for Electric Power Equipment stipulate the method and voltage value of AC dielectric test for reactor. There are 7 UHV reactors installed at the 1000kV Nanyang switch-gear station. In order to examine the insulation performance of these reactors, an AC dielectric test was conducted. The main parameters of AC transmission line include series resistance, series reactance, parallel capacitance and conductance. When the AC transmission line transmits the power, the current on the serial reactor lags behind the voltage and series reactor absorbs reactive power; the voltage on the parallel capacitance lags behind the current and the parallel capacitance sends out reactive power.