Wuhan UHV specializes in producingseries resonance (also known as power frequency withstand voltage test equipment). Next, we will share with you why power frequency withstand voltage test equipment is used?
In practical work, power workers often hear about a high-voltage power testing equipment called series resonance. This device is widely used and well-known in the power industry. So why use the variable frequency series resonance testing device? Before putting high-voltage power cables into use, a resonance test needs to be conducted to find the resonance point of the cable. Therefore, a series resonance test device is needed at this time. This article will briefly introduce this equipment.
The research on this device mainly focuses on the AC withstand voltage test of 220kV high-voltage bushings and isolation control switches, as well as the design and manufacturing of the AC withstand voltage test system for 220kV main transformers. There is a wide range of applicable laws, but the high-voltage environmental testing management departments at the prefecture, city, and county levels, as well as the installation, repair, and testing engineering construction units of power enterprises, do not have ideal pressure resistant equipment. The device mainly consists of a variable frequency power supply, an excitation transformer, a reactor, and a capacitive voltage divider.
The required power capacity is greatly reduced.
Improve the waveform of the output voltage. A resonant power supply is a type of resonant filtering circuit that can improve the waveform distortion of the output voltage, obtain a good sine waveform, and effectively prevent harmonic peak from accidentally passing through the test. Prevent large short-circuit current from burning fault points. In the series resonance state, when the weak point of the insulation of the test product is punctured, the circuit immediately disengages and the circuit current rapidly drops to 1/Q of the normal test current. When the voltage test is completed in the inline resonator or experimental transformer mode, the tapping current immediately increases by tens of times compared to the short-circuit current and tapping current. Therefore, series resonance can effectively detect insulation weaknesses without the concern of large short-circuit currents burning the fault point.
It will not cause any overvoltage recovery. When the test sample breaks down, due to the loss of resonance conditions, the high voltage immediately disappears, the arc immediately extinguishes, and the process of re establishing and developing the working voltage takes a long time. It is easy to disconnect the power supply before reaching the flashover voltage again. This voltage recovery production process is an intermittent oscillation process with continuous energy accumulation, which is long and does not affect the occurrence of any economic recovery overvoltage.
This device has functions such as overvoltage, overcurrent, zero position starting, and system detuning (flashover). The overvoltage and overcurrent protection values can be set according to user needs. The entire unit is lightweight and easy to use on site. The device has three working modes, making it easy for users to flexibly choose according to on-site conditions and improving testing speed. Working modes: fully automatic mode, manual mode, automatic adjustment manual boost mode.
It can store and print data in different locations, and the stored data number is a number, which is convenient for users to identify and search. When the device automatically scans the frequency, the frequency starting point can be set arbitrarily within the specified range, and the scanning direction can be selected up or down. At the same time, the scanning curve is displayed on the large LCD screen, making it convenient for users to intuitively know whether the resonance point has been found. Adopting DSP platform technology, it is convenient to add or remove functions and upgrade according to user needs, and also makes the human-computer interaction interface more user-friendly.
Thevariable frequency series resonance test deviceis a high-voltage power testing equipment that is needed to conduct AC withstand voltage tests on high-voltage cables and find the resonance point. It is deeply loved by power workers and requires them to read the product manual carefully to master this equipment.
