Features of the Program-controlled Ultra-low Frequency High Voltage Generator:
This product combines modern digital frequency conversion advanced technology, adopts microcomputer control, and fully automates voltage boosting, voltage reduction, measurement, and protection. Due to full electronic design, it is small in size and light in weight, with a large LCD screen that is clear and intuitive, and can display output waveforms and print test reports. The design specifications fully comply with the industry standard "General Technical Conditions for Special Testing 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, which results in non-standard sine waveforms, large measurement errors, spark discharge in the high-voltage part, heavy 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 the Program-controlled Ultra-low Frequency High Voltage Generator
The ultra-low frequency insulation withstand voltage test is actually an alternative to the 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 relatively large capacitance, larger capacity test transformers or resonant transformers are required. Such huge equipment is not only heavy and expensive but also very inconvenient to use. To solve this contradiction, the power sector has adopted a method of reducing the test frequency, thereby reducing the capacity of the test power supply. Years of theory and practice at home and abroad have proven that using 0.1Hz ultra-low frequency withstand voltage tests instead of power frequency withstand voltage tests not only provides 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 commonly 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 Cross-linked Polyethylene Insulated Power Cables up to 35kV and Below". Our country 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 voltage 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: 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: designed with dual protection for 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 triggered, with action times both less than 20ms.
5. The high-voltage output protection resistor is designed inside the voltage booster, so no external protection resistor is needed.
6. Due to the adoption of a high-low voltage closed-loop negative feedback control circuit, there is no capacitive rise effect in the output.
