During the testing process, the transformer may experience inter turn or inter phase short circuits, or collisions during transportation, resulting in relative displacement of the coils. Additionally, during operation, the distribution parameters of the transformer winding may change due to electromagnetic tension caused by short circuits and faults. Furthermore, it affects and alters the original frequency domain characteristics of the transformer, such as amplitude changes in frequency response and harmonic frequency point shifts. The transformer winding tester developed based on response analysis method is a novel non-destructive testing equipment for internal faults of transformers. It is suitable for internal structural fault detection of 63kV~500kV power transformers.

The transformer winding deformation tester quantifies the response changes of the internal winding parameters of the transformer in different frequency domains, and determines the degree of change in the internal winding of the transformer based on the magnitude of the change, the amplitude and region of the frequency response change, and the trend of the frequency response change. Therefore, the measurement results can be used to determine whether the transformer has been severely damaged and whether major repairs are needed.


 

1. The acquisition control adopts high-speed and highly integrated microprocessors.

2. This instrument comes with an industrial control computer for independent use, and does not require a laptop. It can also be connected to a laptop through a USB interface.

3. The instrument automatically analyzes and judges the detection results, and generates electronic documents (Word) for saving and printing.

4. High speed dual channel 16 bit A/D sampling (on-site test changes the tap changer, and the waveform curve shows obvious changes).

5. The frequency response method hardware core adopts DDS dedicated digital high-speed scanning technology, which can accurately diagnose faults such as winding distortion, bulging, displacement, tilting, inter turn short circuit deformation, and inter phase contact short circuit through testing.

6. The frequency response method has dual measurement system functions of linear sweep frequency measurement and segmented sweep frequency measurement.

7. The amplitude frequency characteristics of the frequency response method comply with the technical specifications of the national amplitude frequency characteristic tester. The horizontal axis (frequency) has two types of divisions: linear division and logarithmic division, so the printed curve can be a linear division curve or a logarithmic division curve, and users can choose according to their actual needs.

8. The impedance method adopts a three-phase connection single-phase measurement method, which only requires short circuiting on the low voltage side and connecting all three phases at once on the high voltage side. The short-circuit impedance of each phase can be calculated automatically in one measurement.

9. Impedance method can synchronously measure voltage, current, and frequency, and display real-time waveform diagrams for testing

10. The impedance method can use an internal 220V power supply or an external power supply.

1. Frequency response method

Scanning method

Linear scanning distribution
Sweep frequency measurement range: (10Hz) - (10MHz) 40000 sweep frequency points, with resolutions of 0.25kHz, 0.5kHz, and 1kHz.

Segmented sweep frequency measurement distribution
Sweep frequency measurement range: (0.5kHz) - (1MHz), 2000 sweep frequency points;
(0.5kHz)-(10kHz)
(10kHz)-(100kHz)
(100kHz)-(500kHz)
(500kHz)-(1000kHz)

Other technical parameters
Range of amplitude measurement: (-120dB) to (+20dB)
Amplitude measurement accuracy: 0.1dB
Scanning frequency accuracy: 0.01%
Signal input impedance: 1M Ω
Signal output impedance: 50 Ω
Signal output amplitude: ± 20V
Same phase test repetition rate: 99.9%
 
2. Impedance method:
Measurement accuracy: Voltage: 0.2% Current: 0.2%
Impedance range: 0-100%
Voltage measurement range: AC 25V~500V
Current measurement range: AC 0.1A~10A
Working humidity: 0-80%
Same phase test repetition rate: 99.9%