PowerHV® Variable Frequency Resonant Test System | Onsite Mobile Test
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Variable Frequency Resonant 1000kV 6000kV Resonant System for 750kV GIS onsite test Variable frequency resonant test system is used to do AC voltage withstand test on field for capacitive objects, such as power transformers, power cables, turbine and hydraulic generators. At power frequency, since the large capacitance of test objects and required high testing voltage, the power of used source is necessarily high. Compared to traditional AC test systems, variable frequency test system is featured by small dimension, light weight and easy moving. The system is composed by modules which can...

■ Variable frequency power supply ■ Capacitive voltage divider, also as coupling capacitor ■ Control and measurement system Block diagram 2. variable frequency power supply Control & measuring cable Power cable Variable inductance reactor Reactors are in modules, can run in series or parallel, stackable. The insulating shell is made of epoxy reinforced glass-fiber, filled with oil. Usually reactors run a short time at rated current. single insulating case reactor can be 400kV, connected in series, it can output 1600kV. Metal tank reactors are mostly suitable for large capacitance test...

Typical parameters of reactors as below: Rated Rated Current capacity Height Diameter of Total weight Oil weight

Exciter transformer usually has multiple of output taps. It feeds the resonant reactors with suitable power and frequency depending on the load. The exciter transformer is equipped with protection against discharge. Typical parameters of exciter transformer is as below: Voltage divider also functions as high voltage filter and coupling capacitor. Divider is a mandatory part in AC test systems, used for voltage measurement. Voltage and capacitance range of divider can be very wide. Voltage divider is composed by HV arm, LV arm and measurement wire. Sometimes voltage divider can also be used...

Variable frequency power supply A is fed directly from the 380V three-phase AC mains. The voltage goes via vacuum switch with fast protection to three-phase bridge rectification circuit where it is turned to DC pulse voltage. The pulse voltage is again turned to DC smooth voltage by high voltage filter which consists of inductance and capacitance. The DC smooth voltage feeds large power amplifier circuit. Compared to medium frequency power supply of generators group which needs star-delta or asynchronous start-up, the variable frequency power supply starts reliably and easily. In the main...

Controller is the essential part of the whole system. Microcomputer works as controller. All working info is displayed on a screen. The control circuit is independently fed by 220V/50Hz source. It is available of manual control and auto control. Picture as below: Typical parameters of Variable frequency power supply A: Rated Three Single output phase phase power input output voltage voltage Frequency Frequency Frequency Waveform Noise level adjustable adjustable adjustable distortion range precision precision Variable frequency power supply B Basic parameters input power: three phase,...

■ Dual monitor system: there is not only large screen display with multiple interfaces and data, but also additional pointer type voltmeter and ammeter to intuitively display the testing data during the whole test. This dual monitor system is particularly suitable for high voltage testing. ■ Dual over voltage protection: over voltage protection both by hardware and software, to ensure safety of (a) Auto over voltage setting: when hardware protection value is unsuitable, the system automatically revise to l.ltimes of the testing voltage. (b) Independent protection by hardware: protection...