Development of a novel 20 kV 0.1 Hz very low frequency cosine-rectangular voltage generator for multi-functional insulation testing of MV power cables

• Published in: IET generation, transmission & distribution Vol. 12; no. 1; pp. 1 - 8
• Main Authors: Hou, Zhe, Li, Hongjie, Chen, Shuo, Li, Baojie, Lu, Yuxin, Ji, Shengchang
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 01.01.2018
• Subjects: charging switch; cosinusoidal polarity reversing process; discharging switch; frequency 0.1 Hz; IEEE standard 400.2; IEEE standards; insulated gate bipolar transistor series‐connected semiconductor switch; laboratory prototype; L‐C series resonance; multifunctional insulation testing; partial discharge test; partial discharges; PD detection; power cable insulation; power cable testing; Research Article; standard medium voltage cross‐linked polyethylene power cable; standard MV cross‐linked polyethylene power cable; very low frequency cosine‐rectangular voltage generator; very low frequency CRVG; voltage 20 kV; XLPE insulation; insulated gate bipolar transistor series-connected semiconductor switch; PD detection; cosinusoidal polarity reversing process; L-C series resonance; XLPE insulation; partial discharge test; power cable insulation; power cable testing; multifunctional insulation testing; standard MV cross-linked polyethylene power cable; very low frequency cosine-rectangular voltage generator; very low frequency CRVG; voltage 20 kV; laboratory prototype; IEEE standards; standard medium voltage cross-linked polyethylene power cable; frequency 0.1 Hz; partial discharges; IEEE standard 400.2; discharging switch; charging switch
• ISSN: 1751-8687; 1751-8695; 1751-8695
• DOI: 10.1049/iet-gtd.2016.1097

This study covers research and development efforts to develop, design and test a novel very low frequency cosine-rectangular voltage generator (CRVG) specialised not only for a withstand test, but also a partial discharge (PD) test of standard medium voltage (MV) cross-linked polyethylene power cables. The system schematic and operating principle of the proposed system are presented and described. The cosinusoidal polarity reversing process is realised through L–C series resonance. A charging and discharging switch is developed by means of an insulated gate bipolar transistor series-connected semiconductor switch. A laboratory prototype is assembled and tested. Maximum output voltage of the proposed CRVG is measured as 20 kV, which is in accordance with the expected acceptance test voltage level given in IEEE standard 400.2. Finally, the proposed system is applied to PD detection of a 300 m cable circuit with a built-in artificial defect, and the PD locating results are presented, proving the system's feasibility.