Cooperative control between large capacity HVDC system and thermal power plant.pdf

IEEE Transactions on Power Systems, Vol. 14, No. 2, May 1999 629 Cooperative Control Between Large Capacity HVDC System and Thermal Power Plant Kazuo Kat0 Electric Power Development Co , Ltd Koji Yamaji Masakazu Sat0 Sklkoku Electric Power Co., Inc. The Kansai Electric Power Co., Inc. 2-5 Marunouchi 3-3-22 Nakanosima, Kitaku 6-15-1 Gin~a, Chuoku Takamatsu, Japan Osaka, Japan Tokyo, Japan Masuo Goto Tadao Kawai Fellow, IEEE Member, IEEE Hitachi, Ltd. Hitachi, Japan 1-1-1 Kokubucho Abstract - This paper proposes a newly developed cooperative con- trol scheme between an HVDC transmission system and a radially connected thermal power plant. The proposed control scheme aims at stable control of the generator frequency during and after the tranvition from addc parallel connected operation to radially con- nected operation of the HVDC system and the thermal power plant due to loss of ac transmission. The advantage of the proposed control scheme is to minimize the loss of generation in the transition state by the high-speed cooperative control where control quantities, calculated based on the necessary data acquired prior to the occur- rence of the loss of ac transmission, are applied. A prototype of the control equipment was manufactured and subjected to perform- ance evaluation tests by means of a large-scale analog simulator. Keywords: HVDC, generator-HVDC radial system, PLU relay 1. Introduction The development and construction of a 1400MW HVDC trans- mission system has been in progress in the 60Hz area of the Japanese electric power systems as shown in Figure 1 [1]-[3]. This HVDC system is planned to constitute an addc parallel power transmission system in conjunction with a new 2800MW thermal power plant located near the HVDC converter station on the sending side. Fig- ure 2(a) illustrates the circuit configuration of the HVDC converter N A 0 3M]km 1 1 I I Fig. 1 Power system in 60 Hz area of Japan (6 companies) PE-230-PWRS-0-0