Type Selection and Operation of 1000kV Capacitor Voltage Transformer

Capacitor voltage transformer (CVT) decreases the voltage with capacitance bleeder, and complete the work that convert high voltage to low voltage with electromagnetic unit. The low voltage is just what the measurement, protection and monitoring needs. With the increase of the voltage grade, the pitch number of capacitance bleeder increase accordingly, so that the impact of operation conditions on the capacitance bleeder is also strengthened. So in order to guarantee work normally, the type selection of CVT is essential. Otherwise, the improper selection of type will aggravate the influence of operation conditions to CVT, even cause CVT can't operate normally. In order to avoid this, it's the most important thing that reducing the change of impedance rate of capacitance bleeder because of the change of operation conditions as much as possible, especially, the change of impedance of low voltage arm of bleeder because of the change of operation conditions should be avoided. Based on this, operation conditions have great different impact on 1000kV detachable CVT and integrated CVT. When selects the type of CVT, if don't realize this, it will bring very unfavorable influence to the normal operation of 1000kVCVT. So, once the type selecting of the equipment is improper which will cause that it's difficult to guaranteeing the running quality of 1000kV CVT. In order to avoid the emergence of this situation, operation state of CVT with different structure is been analysed in this paper, which is for 1000kV equipment selecting type to consult.