Transformer Tester with Linear Sweep and FRA

After a transformer is designed and manufactured, its coils and internal structure are fixed. For multi-winding transformer coils, identical voltage ratings and winding methods translate to fixed parameters (Ci, Li), which lock in each coil's frequency-domain characteristic response. As a result, the frequency spectra of the three-phase coils can be compared effectively.

Transformer winding distributed parameters change when interturn/phase-to-phase short circuits happen during testing, coils shift due to transportation impacts, or electromagnetic forces deform coils during short-circuit/fault operation. These changes disrupt the transformer's original frequency-domain traits, including frequency response amplitude fluctuations and resonance frequency offsets. Our Transformer Winding Tester—engineered using response analysis—is a state-of-the-art non-destructive tool for detecting internal transformer faults, applicable to 63kV–500kV power transformers.

This tester quantifies how transformer winding parameters respond across different frequency ranges. It assesses the extent of internal winding deformation by evaluating parameter change magnitudes, frequency response variation amplitude/regions, and trend patterns. Using these insights, users can quickly determine if a transformer is severely damaged and needs overhaul.

1. The transformer winding deformation tester consists of a measurement unit and analysis software. The measurement unit is controlled by a high-speed single-chip microcomputer and comprises signal generation and signal measurement. The measurement unit connects to a tablet or laptop via a USB interface.
2. During testing, only the transformer's connecting busbars need to be removed; all tests can be completed without lifting the transformer's cover or disassembling it.
3. The instrument features multiple linear frequency sweep measurement systems, with a frequency sweep range up to 10MHz. The frequency sweep interval can be set to 0.25kHz, 0.5kHz, and 1kHz, providing more detailed analysis of transformer deformation.
4. The instrument is highly intelligent and easy to use, with features such as automatic range adjustment and automatic sampling frequency adjustment.
5. The software uses the Windows platform and is compatible. It provides users with a more convenient and user-friendly display interface.
6. It provides historical curve comparison analysis, allowing multiple historical curves to be loaded simultaneously for observation. Any curve can be selected for horizontal and vertical analysis. It is equipped with an expert intelligent analysis and diagnosis system that can automatically diagnose the state of the transformer windings. It can load six curves simultaneously, automatically calculate relevant parameters for each curve, automatically diagnose winding deformation, and provide diagnostic reference conclusions.
7. The software has powerful management functions, fully considering the needs of on-site use. It automatically saves environmental condition parameters to provide a basis for transformer winding deformation diagnosis. Measurement data is automatically saved, and it has a color printing function, making it convenient for users to generate test reports.
8. The software is highly user-friendly. Most measurement conditions are selectable options. Detailed transformer parameters can be saved for diagnostic reference and do not need to be entered on-site; information can be added or modified later, making it more convenient to use.
9. The software is highly intelligent. After connecting the input and output signals and setting the condition parameters, all measurement work can be completed. Historical waveform curves can be opened at any time during measurement for comparison and observation, and measurement can be stopped at any time.
10. The time required for each phase measurement is less than 60 seconds. The total time required for winding deformation measurement of a power transformer with high, medium, and low windings (regardless of capacity and voltage level) is no more than 10 minutes. Wiring personnel can freely arrange the signal input and output leads without affecting the measurement results. Wiring personnel can remain on top of the transformer oil tank, eliminating the need to climb down, thus reducing labor intensity.