Series Resonance Test Equipment
Product Introduction
This device is mainly designed and manufactured for the AC withstand voltage test of 11kV/30MW hydro-generators. The reactor is designed in two separate parts
This device mainly consists of a variable frequency control power supply, an excitation transformer, a reactor, and a capacitive voltage divider.
Advantages of series resonance in power systems:
1. The required power supply capacity is greatly reduced. The series resonance power supply uses the resonance between the resonant reactor and the test object's capacitance to generate high voltage and large current. In the entire system, the power supply only needs to provide the active power consumption part of the system, so the power required for the test is only 1/Q of the test capacity.
2. The weight and volume of the equipment are greatly reduced. In the series resonance power supply, not only the bulky high-power voltage regulating device and the ordinary high-power power frequency test transformer are omitted, but also the resonant excitation power supply only needs 1/Q of the test capacity, greatly reducing the system weight and volume, generally 1/10-1/30 of the ordinary test device.
3. Improve the waveform of the output voltage. The resonant power supply is a resonant filter circuit, which can improve the waveform distortion of the output voltage, obtain a very good sine waveform, and effectively prevent the harmonic peak from causing false breakdown of the test object.
4. Prevent large short-circuit currents from burning the fault point. In the series resonance state, when the insulation weakness of the test object is broken down, the circuit immediately detunes, and the loop current rapidly drops to 1/Q of the normal test current. In contrast, when using parallel resonance or test transformer method for withstand voltage test, the breakdown current immediately rises dozens of times. Compared with the two, the short-circuit current and breakdown current differ by hundreds of times. Therefore, series resonance can effectively find insulation weaknesses without the concern of large short-circuit currents burning the fault point.
5. No recovery overvoltage will occur. When the test object breaks down, due to the loss of resonance conditions, the high voltage immediately disappears, the arc is extinguished immediately, and the re-establishment process of the recovery voltage is very long, making it easy to disconnect the power supply before reaching the flashover voltage again. This voltage recovery process is an intermittent oscillation process of energy accumulation, which is long and does not produce any recovery overvoltage.
◆ Reference schemes for resonant test device selection:
A. Reference scheme for cable resonant test device selection
B. Reference scheme for generator resonant test device selection
C. Reference scheme for substation electrical equipment resonant device selection
D. Reference scheme for CVT calibration resonant step-up device selection
BPXZ-L Series Resonance Test EquipmentProduct Aliases
Variable frequency resonance, variable frequency series resonance, series resonance, series resonance transformer, series resonance test equipment, generator AC withstand voltage resonant step-up device
Product Features
1. The device has protection functions such as overvoltage, overcurrent, zero-position start, system detuning (flashover), etc. The overvoltage and overcurrent protection values can be set according to user needs. When the test object flashes over, the flashover protection acts and can record the flashover voltage value for test analysis.
2. The single component weight of the entire device is very light, with a maximum of no more than 40kg, making it convenient for on-site use.
3. The device has four working modes, allowing users to flexibly choose according to on-site conditions to improve test speed.
The working modes are: fully automatic mode, manual mode, automatic tuning manual step-up mode
4. It can store and print data remotely. The stored data numbers are numeric, which helps users identify and find them conveniently.
5. When the device automatically sweeps frequency, the frequency starting point can be arbitrarily set within the specified range, and the sweep direction can be selected upward or downward. At the same time, the large LCD screen displays the sweep curve, allowing users to intuitively understand whether the resonance point is found.
6. It adopts DSP platform technology, which can conveniently add or upgrade functions according to user needs, and also makes the human-machine interface more user-friendly.
