Portable Frequency Conversion Series Resonance Withstand Voltage Test Device
The portable frequency conversion series resonance withstand voltage test device is mainly composed of a variable frequency power supply, an excitation transformer, a reactor, and a capacitive voltage divider. This device is mainly designed and manufactured for AC withstand voltage tests of all electrical main equipment such as 10kV cables and below, main transformers, bus switches, etc. The reactor adopts multiple separate designs, which can meet the test conditions for high voltage and small current equipment, as well as the low voltage AC withstand voltage test requirements for 10kV cables. It has a wide range of applications and is an ideal withstand voltage equipment for municipal, county-level high voltage test departments and electric power installation, repair and test engineering units.
Portable Frequency Conversion Series Resonance Withstand Voltage Test Device
Technical Parameters
Ambient temperature: -10～45℃
Ambient humidity: ≤90%
Altitude: ≤2000M
Power input: 220V±10% single phase 50Hz output 0～220V (≤10KW)
380V±10% three phase 50Hz output 0～400V
Rated test capacity: 0～8000KVA (optional)
Resonant voltage: 0～1000KV (optional)
Frequency adjustment range: 0.1～300Hz
System measurement accuracy: 0.5 level
Frequency adjustment resolution: 0.01Hz
Instability: ≤0.05%
Output waveform: sine wave
Waveform distortion rate: ≤0.5%
Noise: ≤60dB
Reactor Q value: 30～200 (optional)
Advantages of the portable frequency conversion series resonance withstand voltage test device in power systems: The required power supply capacity is greatly reduced. The series resonance power supply uses resonant reactors and the capacitance of the test object to generate high voltage and large current. In the entire system, the power supply only needs to provide the active power consumption part of the system, so the power required for the test is only 1/Q of the test capacity; The weight and volume of the equipment are greatly reduced. In the series resonance power supply, not only the bulky high-power voltage regulation device and the ordinary high-power power frequency test transformer are omitted, but also the resonant excitation power supply only needs 1/Q of the test capacity, which greatly reduces the system weight and volume, generally 1/10-1/30 of ordinary test devices; Improve the waveform of the output voltage. The resonant power supply is a resonant filter circuit, which can improve the waveform distortion of the output voltage, obtain a very good sine waveform, and effectively prevent the harmonic peak from causing false breakdown of the test object; Prevent large short-circuit currents from burning the fault point. In the series resonance state, when the insulation weakness of the test object is broken down, the circuit immediately detunes, and the loop current rapidly drops to 1/Q of the normal test current. In contrast, when using parallel resonance or test transformer method for withstand voltage tests, the breakdown current immediately rises dozens of times. Compared with the two, the short-circuit current and breakdown current differ by hundreds of times. Therefore, series resonance can effectively find insulation weaknesses without the worry of large short-circuit currents burning the fault point; No recovery overvoltage will occur. When the test object breaks down, due to the loss of resonance conditions, the high voltage immediately disappears, the arc is immediately extinguished, and the re-establishment process of the recovery voltage is very long, making it easy to disconnect the power supply before reaching the flashover voltage again. This voltage recovery process is an intermittent oscillation process of energy accumulation, with a long process, and no recovery overvoltage will occur
