Guide for the Frequency Domain Spectroscopy Measurement for transformer bushing CSG:Deng Jun

Guide for the Frequency Domain Spectroscopy Measurement for transformer bushing CSG:Deng Jun

Contents 1 Frequency Domain Spectroscopy 2 Research Basis 3 Applications 4 Purpose of the Guide 5 Scope of the Guide 6 Working Group 7 Management and Schedule

1 Frequency Domain Spectroscopy Polarisation processes Bushing The equivalent circuit tanδ=i loss /I charge = ' r '/ ' r =C''/ C'.

1 Frequency Domain Spectroscopy Effect of thermal, electrical, and chemical factors, and water Separate impacts of oil conductivity and moisture

2 Research Basis Broadband Dielectric Spectrometers IDAX 300 DIRANA Oil-impregnagted insulation paper

tan tanδ 2 Research Foundation 1 2 3 4 5 10 2 10 1 10 0 0.7% 1.0% 1.6% 2.8% 3.3% 10 0 10-1 0 天 7 天 18 天 27 天 10-1 10-2 10-2 10-3 10-3 10-2 10-1 10 0 10 1 10 2 10 3 f/hz Effect of moisture content 10-3 10-2 10-1 10 0 10 1 10 2 10 3 f/hz Effect of aging

2 Research Foundation DP versus Aging Time tanδ versus freuency

2 Research Foundation Insulation moisture content Water Content 0.5% i 2(0.5%) 2(5%) 2(0.5%) i 1 5 Conductive rod 1 2 3 5% Permittivity 4 5 6 Water diffusion direction Temperature Water Content in Oil Water Content in paper 10ppm 30ppm (0.5%) (5%) 20 C ε 1 =2.13 ε 1 =2.13 ε 2 =4.58 ε 2 =5.17 80 C ε 1 =2.06 ε 1 =2.06 ε 2 =4.66 ε 2 =5.45

2 Research Foundation Insulation moisture content and effect of temprature Electric field distribution at 20 Electric field distribution at 80 the outer field strength decreased by 5.6%, the inner field strength increased by 8.1%. the outer field strength decreased 1.3% from 80 to 20, inner field strength increased 1.8% 9

10 2 Research Foundation Test Results of FDS 26kV Bushing

11 2 Research Foundation Test Results of FDS 40.5kV Bushing

12 2 Research Foundation Test Results of FDS 72.5kV Bushing

13 2 Research Foundation Test Results of FDS 72.5kV Bushing

14 2 Research Foundation Test Results of FDS 72.5kV Bushing

3 Applications Case 1 Conductive rod rusty FDS Water Content 2.7% Water Content 4.4%

3 Applications Case 2 6(6.7%) 2(7.42%) FDS 5(3.84%) 4 (1.78%) 1(7.29%) 7 (1.36%) 8 (1.16%) 9 (3.21%) 3(2.50%) 10(5.27%) Water Content 4.8% Water Content Distribution Seal failure

3 Applications Case 3 FDS Water Content 2.1% X-wax of the insulation paper PD

3 Applications Case 4 Technical Informationof ABB

4 Purpose of Guide The purpose of this guide is to present FDS measurements for transformer bushings Insulation aging Insulation moisture X-wax produced by PD There is a draft Use Guide for Dielectric Frequency Response Test applied to the transformers. And it has been proved that dielectric frequency response test is a validity method to determine the moisture content in transformer s solid insulation. But the bushings is not in the scope of the above draft for PC57.161

5 Scope of Guide This guide applies to the dielectric loss frequency domain spectroscopy (FDS) measurement for transformer bushings. It establishes the method to measure the dielectric response at different frequencies and to detect the insulation defects of bushings. The guide includes the following topics: Safety precautions; Requirements for measuring instrument; Measurement methods for the frequency domain spectroscopy of bushings; Data analysis and assessment; Maintenance Suggestion Annex (typical examples about the relation between dielectric loss frequency domain spectroscopy and insulation defects).

6 Working Group Approximate number of entities expected to be actively involved in the development of this project: 7 (1) China Southern Power Grid; (2) State Grid Corporation of China; (3) Tsinghua University; (4) Southwest Jiaotong University; (5) ABB; (6) Siemens; (7) Alstom.

7 Management and Schedule Some measures have been taken to ensure that the project can be completed: Face to face technical exchange with IEEE Transformer Committee each year in the United States; Form close connection with the IEEE Inc. Beijing Representation Office; Invite IEEE P1870 Chairman(Yao Xiao) to guide the implementation of this project;

7 Management and Schedule June 2018 PAR approved Jan. 2019 Draft V1 Jan. 2020 Draft V3 Aug. 2020 Sponsor ballot July 2018 1 st meeting Aug. 2019 Draft V2 June 2020 Final draft Dec. 2020 Submit Revcom