HCL-8002A Transformer Winding Deformation Tester (Frequency Response - Short-circuit Impedance)

The HCL-8002A transformer winding deformation tester has two measuring methods: frequency response method and low-voltage short-circuit impedance method. Two different methods are used to measure power transformer winding, fully reflect the features of transformer winding and correctly diagnose and analyze winding deformation. The perfect combination of two methods can save test time and improve working efficiency. 

The transformer winding deformation tester (frequency response method) is used to test 6kV and above power transformer as well as other special transformer. It is inevitable that power transformer is subject to all kinds of short-circuit current impacts or physical strike in the process of operation or transportation. Influenced by strong electro-dynamic force caused by short-circuit current, transformer winding is likely to lose stability and leads to permanent deformations, such as local distortion, bump or shift etc, which would impose a significant effect on safe operation of transformer. According to national electric power industry standards IEC/IEEE/ANSI, frequency response method is utilized to measure the deformation of transformer winding. Features of amplitude-frequency response of transformer's each winding are detected; detection results are compared in a vertical or horizontal manner. Based on the variation of amplitude-frequency response features, possible deformation of transformer can be figured out.  

The transformer winding deformation tester (low-voltage impedance method) is an intelligent instrument. It is specially used for measuring impedance attributes of high or medium power transformer. "The low-voltage short-circuit impedance test or frequency response method shall be adopted to measure the winding deformation as original record before 110kV and above transformer leaves the factory and is put into use"."If the transformer is subject to sudden short-circuit, low-voltage short-circuit impedance test or frequency response method is recommended to measure the winding deformation. The results need to be compared with original record. Only those transformers without faults can be allowed to put into use". The low-voltage impedance test can correctly reflect the variation of impedance value before and after the winding deformation. Measured data is correct and stable thanks to digital signal process technologies, such as voltage&current high-precision AC synchronous sampling and FFT. The instrument adopts three-phase automatic measuring mode or single-phase mode to make low-voltage side reliably connected. After transformer parameters are input, the instrument is able to automatically measure and calculate each phase impedance and impedance error percentage. The voltage and current waveform are displayed in the test process, so it is more suitable for on-site use. 

The system is composed of measuring part and analysis software part. The analysis part is completed by laptop. Measuring part is connected with laptop via USB cable. 

Attention: For your convenience, all the parts related to short-circuit impedance are put in the latter of each section. 

1. Main technical features

-The sweeping frequency method is used to measure the features of transformer winding without hanging the cover and disassembling transformer. Through detecting amplitude-frequency response features of each winding, permanent deformations of 6kV and above transformer such as twist, bump or shift etc will be correctly measured. 

-The measuring speed of frequency response method is fast, just 1min-3min for single winding. 

-The frequency precision of frequency response method is very high, higher than 0.001%. 

-The frequency response method adopts digital frequency synthesis, and frequency stability is higher.  

-The frequency response method adopts 5000V voltage to isolate, which can ensure the safety of test computer.   

-Be able to load 9 curves at the same time; automatically calculate relevant parameters of each curve; automatically diagnose deformation condition of winding and provide conclusions for reference 

-Both Software and hardware conform to national electric power industry standards - IEC/IEEE/ANSI. 

-As for the short-circuit impedance method, there is no need to externally connect voltage regulating source. Three-phase self-measurement by only adopting AC220V low-voltage source. The voltage is automatically applied to AB, BC and VA high-voltage winding. The data is recorded and impedance error percentage is calculated automatically. Measured results are easy to read.

-The short-circuit impedance method can be used to measure the impedance of any transformer regardless of its capacity.   

-Waveform atlas of testing current and voltage is displayed during the test in order to facilitate real-time monitoring. 

-The short-circuit impedance method can measure the inductance and zero-sequence impedance of the transformer. 

-Adopt the Windows; be compatible with Window 2000, Window XP, Win7 and Win8. 

-Use the database to store and manage test data

-Management function of the software is strong; for convenient on-site use, measured data is automatically stored and generated into Word test report (office software is needed to be installed in advance) or JPG report. 

-The software is highly intelligent. After input and output signal are well connected, only pressing one button can complete all measuring work.

-Simple and user-friendly software interface

2. Main technical parameter

-Measuring speed: 1min - 3min for single-phase winding 

-Output voltage: Vpp-25V, self-adjustment during the test

-Output impedance : 50Ω

-Input impedance: 1MΩ (50Ωmatch resistor is internally installed in the response channel)

-Sweeping frequency range: 50Hz－2MHz or 50Hz－10MHz (Optional)

-Frequency precision: 0.001%

-Quantization precision of acquisition channel : 14 bit

-Sweeping frequency method: linearity or logarithm, sweeping frequency interval and point number can be set at random 

-Curve display: amplitude curve (phase frequency curve, optional)

-Measuring DR width: －120dB～20dB

-Supply voltage: AC0-220V±10%

-Test current via impedance method: 0-10A

-Frequency of impedance method:50Hz/60Hz 

-Weight of main machine: 4.5kg