Speakers at Plenary Lecture Scheduled to be Held on 14 October, 2019

In the past, the system voltages of the AC and DC transmission systems has been upgraded to UHV and EHV levels to reduce a loss of transmission and the short-circuit power of the power systems also has been increasing due to expansion of the networks. The system requires a circuit breaker for larger interrupting capacity per break resulting in the development of circuit breakers with 550 kV voltage rating and 63 kA breaking capability, which enables to the design and construction of an 1100 kV double break circuit breakers. In addition, the general trend has been to reduce the size and complexity of the switching equipment. SF₆ switching technology with excellent dielectric and extinguishing properties, can attains extremely high reliable networks.

However, environmental protection concerns are increasing more and more to reduce SF₆ gas applications with high global warming potential, in spite of considerable effort that has been made to reduce the leakage of gas from equipment. Circuit breakers using non-SF₆ gas with lower high global warming potential are demonstrated in the field. Vacuum interrupters with higher voltages up to 550/420 kV ratings have been proceeding intensively.

Another future solution without SF₆ gas is a circuit breaker composed of power electronic devices. Semiconductor switching equipment is still rather expensive has the advantage of rapid current interruption at any phase angle of the current waveform. HVDC circuit breakers based on a hybrid mechanical switch and electronic devices as well as a series connected vacuum interrupters with current injections are under development in order to realize the future multi-terminal 525/320 kV HVDC networks.

In the presentation, Technical tends and forecasts of AC and DC switching technologies applicable to future power systems will be presented.

He joined CIGRE Working Groups 13.07 and A3.07 “Controlled Switching”. He was the Convener of CIGRE Working Group A3.22 “Technical requirements for UHV substation equipment” in 2006 and A3.28 “EHV and UHV switching phenomena”. WGs published the Technical Brochures, TB 362, TB467 and TB567 to support the UHV international standardization. He was also a member of JWG A4/B4.34 and contributed to investigate the state of the art DC circuit breakers.

He was the chairman of CIGRE Study Committee A3 dealing with transmission and distribution equipment from 2012 to 2018. He was awarded as the CIGRE honorary member in 2018. During the term of the CIGRE chairman, he published several Technical Brochures on equipment and a CIGRE Green book on “Switching equipment” intended for an educating textbook the young engineers.

Changjiang Chair Professor, postgraduate candidate teacher, State Council discipline appraisal component member, national outstanding youth science foundation winner, the leader of “Ministry of Education innovation team”.

Executive Vice-President of school of electrical engineering at Xi'an Jiaotong University, vice director at “State Key Laboratory of Electrical Insulation & Power Equipment”, China Electro- technical Society member, Vice director of research department at “Electrical Equipment and Intellectualization Lab”, Head of Institution for electrical contact and electric arc of Chinese Electro-technical Society, gaseous discharge and application international conference scientific committe member.

There are 36 scientific research items held by him successively, like “The National Natural Science Foundation of China ” Project 1 item, “The National Outstanding Youth Science Foundation Project” 1 item, National Defense “973” Topic 1 item and National 863 project 1 item.

He has also published papers in domestic and foreign academic journals IEEE Trans, IEE Proceedings, IEICE Trans, J of Physics, Chinese Electrical Engineering Journal and other published papers 160, SCI indexed 40, EI indexed 72; Publishes Academic Monograph 2, The Cooperation Publishes 15 plans Teaching Material 1; Authorization patent of invention 11 items, Utility Invention patents 5 items; Registration software copyright 3 items; The State Advance in Technology the Second Award 2 items, The National Natural Sciences forth Award 1 item, The Ministry of Education Advance in Technology First Award 1 item, the Ministry of Education The State Nomination Technical Invention by Education Ministry First Award 1 item.

He has been supervised 16 Ph.D. students including 9 graduators, 38 postgraduate students including 25 graduators, and every year instructs 4 undergraduates on course graduation paper project. What’s more, the guided graduate student obtained the first Prize on The Frist GE foundation “the Edison cup” the technological innovation competition (only 5 in whole nation), the Shanxi Province challenge cup Second Prize, the Beijing East scholarship and so on.

He was made a Fellow of the Institution of Mechanical Engineers (IMechE) in 1987, and a Fellow of the Institution of Electrical Engineers (IEE now IET) in 1988. He is a Chartered Engineer in the UK (C. Eng) and is also a European Engineer (Eur. Ing). He was made a Fellow of the IEEE in 2007 for his contribution to Vacuum Interrupter technology.

He has spent the past 30 years in the high voltage part of the Electrical Supply Industry working for equipment manufacturers. Much of the time was spent in setting up, leading, and being part of, teams performing world class Industrial Research and Development. This was recognised by the personal awards of the Nelson Gold Medal from GEC in 1996, the J J Thomson Medal from the IEE in 2002, Fellowship of the IEEE in 2007, the International Electrotechnical Commission award in 2010 (IEC 1906 award). More recently he was also awarded the 2018 IEEE SA International Award for his contribution to the development of ANSI/IEEE standards.

Eco-friendly electric power equipment have been one of the most interesting subject in the power equipment industry for more than 15 years. After SF₆ has been identified as a greenhouse gas according to Kyoto Protocol in 1997, many manufacturers have researched and developed some eco-friendly power equipment spontaneously because Kyoto Protocol had no legal binding force. However, after Paris Agreements was adopted at COP 21 in 2015, the eco-friendly power equipment became more interesting object.

The Paris Agreement requires all Parties to put forward their best efforts through nationally determined contributions and to strengthen these efforts in the years ahead. This includes requirements that all Parties report regularly on their emissions and on their implementation efforts. For these reasons, the utility company in Korea also set up action plan to reduce the emission of the greenhouse gas and to replace SF₆ equipment into SF₆ free products.

The utility company in Korea have a plan to replace SF₆ switchgear to SF₆ free switchgear of 170kV rating voltage. And 70kV rating voltage transmission network will be set up with eco-friendly equipment. Therefore many eco-friendly switchgear and equipment with vacuum interrupter or/and alternative insulation gas are under development.

In the presentation, the environmentally friendly policy of the utility company to reduce the emission of the greenhouse gas from a power equipment and the state of the eco-friendly power equipment development in Korea will be presented.

In 2005, Jaeseop Ryu joined LSIS Co., Ltd., Electrotechnology R&D Division. His main research area are the electromagnetic field analysis, dielectric performance research of the gas insulation medium such as SF₆, dry-air, and SF₆ alternative gas. And he also have researched about high voltage vacuum interrupter and the arc simulation of gas circuit breaker with an alternative gas. In 2010, he developed 170kV single break vacuum interrupter for gas insulated switchgear. As the series of the high voltage vacuum interrupter research, he developed the vacuum interrupters of 72.5kV and 145kV rating voltages. From 2017, he have been researching about the insulation characteristics and the arc simulation of SF₆ alternative gas. And he is developing 72.5kV SF₆ free switchgear with vacuum interrupter.

He was a member of CIGRE Working Group A3.27 “The impact of the application of vacuum switchgear at transmission voltages” from 2009 to 2014. He is also a member of CIGRE Working Group D1.67 “Dielectric performance of new non-SF₆ gases and gas mixtures for gas-insulated systems” from 2017. And he is a member of local organization committee of ICEPE-ST in Korea.