AC withstand voltage test is a strict, effective, and direct test method for identifying the insulation strength of electrical equipment. It is decisive in judging whether electrical equipment can be put into operation, and it is also important for ensuring the insulation level of equipment and avoiding insulation accidents...
For the AC power frequency withstand voltage test of these devices, if traditional test equipment (i.e., power frequency test transformers) is used, due to the large capacity required for the test, the test transformer and voltage regulator are very bulky, and it is also difficult to provide a large-capacity test power supply on site, making on-site testing inconvenient. The power frequency resonant device has advantages in terms of test power supply capacity, equipment weight, test waveform, and investment. This device is mainly designed and manufactured for the AC withstand voltage test of hydro generators with a single unit capacity of 250MW and below.
What are the main technical and functional advantages of the DYXZ series portable variable-frequency resonant voltage boosting device for cables?
1. Due to the full compensation of reactive power in resonance, the power of the power supply and equipment is only less than 1/10 (1/Q10) of the capacity required by the test object; with the same capacity, the volume is small, the weight is light, the device output capacity is large but the required power supply capacity is small, the price is low, and the operation is convenient and safe.
2. Series resonance is actually a current filtering loop, which makes the current through the test object basically fundamental current, and the output voltage waveform distortion rate (THD) is small, superior to all existing types of AC withstand voltage equipment.
3. The short-circuit current after flashover or breakdown of the test object is only less than 1/10 (1/Q) of the test current before the short circuit, which can effectively prevent the expansion of damage to the fault point after breakdown.
4. After flashover, the arc is automatically extinguished immediately. After arc extinction, the process of restoring the resonant state and establishing voltage takes a long time (seconds), which is a steady-state establishment process, with no concern about voltage overshoot and no danger of recovery overvoltage in microsecond or millisecond transient processes.
