Basic Principle of Variable Frequency Series Resonance:



The variable frequency series resonance withstand voltage test uses the inductance of the reactor and the capacitance of the test object to form an LC series circuit. By adjusting the output voltage frequency of the variable frequency power supply, series and parallel resonance is achieved, obtaining high voltage on the test object. This is a new method for high voltage testing, highly praised by experts, and has been widely used both domestically and internationally.



2. Characteristics of the Variable Frequency Series Resonance Test Device:



The variable frequency series resonance test device has a large output capacity, high output voltage, and can be arbitrarily combined with reactors for AC withstand voltage tests on different test objects.



The variable frequency series resonance test device is small in size and light in weight, with each piece weighing no more than 50kg, making it particularly convenient for field tests.



The variable frequency series resonance test device has good protection functions, including overvoltage protection, overcurrent protection, time protection, flashover protection, overheat protection, and module protection.



The variable frequency series resonance test device is extremely simple to operate and has both manual and automatic modes.



The variable frequency series resonance test device uses a large screen, making test data clear at a glance, and can print test results.



The variable frequency series resonance test device has no risk of overvoltage after the test object breaks down, causing relatively little damage to the test object.



The variable frequency series resonance test device requires only a small power supply capacity for testing, which is only a fraction of that required for power frequency transformer testing, solving the problem of difficulty in finding a power source on site.



3. Scope of Application:



Suitable for AC withstand voltage testing of 400mm2/35kV cross-linked cables with a length of 2000m.



4. Operating Environmental Conditions:



1 Ambient temperature: -10℃ to 40℃



2 Relative humidity: not greater than 90%



3 Altitude: below 2500 meters



5. Standards Referenced and Implemented for Equipment Manufacturing



1DL/T849.6—2004     High Voltage Resonant Test Device;



2GB 6450—1986        Dry-type Power Transformer;



3DL/T848.2—2004     Test Transformer;



4GB/10229—1988      Reactor;



5GB/T11920—1989     General Technical Conditions for Control Devices;