Product Details

Triple Frequency Induced Withstand Voltage Tester



  Product Features 

  This product, also known as triple frequency power generator, triple frequency voltage generator, and triple frequency high voltage generator, is designed to meet the requirements of the triple frequency induced withstand voltage test and partial discharge test as specified in <>, <> and —1995. 

  The induced withstand voltage test for transformers and instrument transformers is an important test to verify whether the product meets national standards. The longitudinal insulation induction test of winding layers, turns, sections, and phase-to-phase insulation is an important item to assess whether the winding meets requirements. To increase the test voltage of the winding without causing over-saturation of the transformer or instrument transformer core, which would lead to excessive excitation current, the test frequency is usually increased to 100Hz-400Hz. 

  There are several methods to obtain a 100Hz-400Hz power supply, among which the most applicable ones are: 

  Combining three variable-frequency generators to produce 100Hz-400Hz; 

  Combining three single-phase transformers to produce 150Hz, and the most convenient method is the latter. 

  The combination method of three single-phase transformers: the primary side is star-connected, and the secondary side is open-delta connected. When the core is not saturated, the main magnetic flux it produces is necessarily a flat-topped wave. Since the flat-topped main magnetic flux contains a significant component of third harmonic magnetic energy φ3, and the frequency of the third harmonic magnetic flux is f3=3f1, the main magnetic flux induces a third harmonic phase electromotive force. 

  Because the primary side is star-connected and the secondary side is open-delta connected, the core operates in a saturated state, and the no-load current i is a peaked wave. In addition to the fundamental component, it also contains higher harmonics. Among the higher harmonics, the amplitude of i is relatively large. Due to the open secondary, the three-phase fundamental components cancel each other out, leaving only the third harmonic output. 

  The entire machine's voltage output is achieved by tuning to resonance when the power supply is at 150Hz. When the voltage rises, a certain squealing sound during resonance is normal. 

  SSF Triple Frequency Induced Withstand Voltage Tester Technical Parameters 

  Rated capacity: 5-100kVA 

  Input: three-phase 380V, 50Hz sine wave 

  Output: 0-300V, 0-500V, 0-1000V (custom voltages available), 150Hz, 

  Waveform distortion ≤1% 

  Capacity: 3-150kVA 

  No-load operation time: ≤5 minutes 

  Load operation time: 40-60 seconds