Features of Program-controlled Ultra-low Frequency High Voltage Generator:
This product integrates modern digital frequency conversion advanced technology, adopts microcomputer control, and fully automates voltage boosting, voltage reduction, measurement, and protection. Due to full electronization, it is small in size and light in weight, with a large-screen LCD display that is clear and intuitive, and can display output waveforms and print test reports. The design indicators fully comply with the industry standard "General Technical Conditions for Special Test Instruments for Power Equipment, Part 4: General Technical Conditions for Ultra-low Frequency High Voltage Generators". It is very convenient to use. Currently, both domestic and international methods use mechanical modulation and demodulation to generate ultra-low frequency signals, resulting in non-standard sine waveforms, large measurement errors, spark discharge in the high-voltage part, bulky equipment, and the second and fourth quadrants of the sine wave require high-power high-voltage resistors for discharge shaping, so the overall power consumption of the equipment is high.
Product Uses of Program-controlled Ultra-low Frequency High Voltage Generator
Ultra-low frequency insulation withstand voltage test is actually an alternative to power frequency withstand voltage test. We know that when conducting power frequency withstand voltage tests on large generators, cables, and other test objects, due to their insulation layers having large capacitance, larger capacity test transformers or resonant transformers are needed. Such huge equipment is not only bulky and expensive but also very inconvenient to use. To solve this contradiction, the power sector has adopted reducing the test frequency, thereby reducing the capacity of the test power supply. From years of theory and practice at home and abroad, it has been proven that using 0.1Hz ultra-low frequency withstand voltage test instead of power frequency withstand voltage test not only has the same equivalence but also greatly reduces the size and weight of the equipment. Theoretically, the capacity is about one five-hundredth of that of power frequency, and it is simple to operate, with more advantages compared to power frequency tests. This is why developed countries generally adopt this method. The National Development and Reform Commission has formulated the industry standard "Test Method for Ultra-low Frequency (0.1Hz) Withstand Voltage of 35kV and Below Cross-linked Polyethylene Insulated Power Cables". China is promoting this method, and this instrument is developed based on this national need. It can be widely used in AC withstand voltage tests for cables and large high-voltage rotating motors.
The Program-controlled Ultra-low Frequency High Voltage Generator can overcome these shortcomings and has the following features:
1. For ultra-low frequency with rated voltage less than or equal to 100kV, a single-stage structure with one booster is adopted, greatly reducing the overall weight and enhancing load capacity.
2. Current, voltage, and waveform data are directly sampled from the high-voltage side, ensuring accurate data.
3. It has overvoltage protection function. When the output exceeds the set voltage limit, the instrument will shut down for protection, with an action time of less than 20ms.
4. It has overcurrent protection function: designed with dual protection on both high and low voltage sides. The high-voltage side can perform precise shutdown protection according to the set value; when the current on the low-voltage side exceeds the rated current, shutdown protection will be activated, with action times both less than 20ms.
5. The high-voltage output protection resistor is designed inside the booster, so no external protection resistor is needed.
6. Due to the adoption of high and low voltage closed-loop negative feedback control circuit, there is no capacitance rise effect in the output.
