Papers by Author: You Jie Ma

Abstract: ADRC is Active disturbance rejection control,it inherits from proportional–integral–derivative (PID) the quality that makes it such a success: the error driven, rather than model-based, control law; it takes from modern control theory its best offering: the state observer; it embraces the power of nonlinear feedback and puts it to full use; it is a useful digital control technology developed out of an experimental platform rooted in computer simulations. ADRC is made possible only when control is taken as an experimental science, instead of a mathematical one. It is motivated by the ever increasing demands from industry that requires the control technology to move beyond PID, which has dominated the practice.

Abstract: APF has its outstanding features comparing with PPF, it is a new type harmonic suppression and reactive power compensation device. This paper makes an introduction about two key technologies about APF, and it makes a prediction to the trend of the key technologies. APF is the main harmonic suppression technique at present and in the future. At present, there are large of loads in every industry, such as, electric arc furnace in steel industry, the welder in automotive industry, and these industries are important sectors of the national economy, we can do not stop them running, only installing APF in the appropriate location .Therefore, APF has broad prospects for development in various industries.

Abstract: In the field of renewable energy, wind energy has one of the best prospects in all industries. It is a kind of clean, practical, economic and environmentally friendly alternative energy. It also has the advantages of high energy converting rate, large industrial scale、high level technology and so on. Thus in recent years, the developing trend of global wind power industry is rapid, and the growth tide of China has been enhanced significantly. This paper discusses the general development of wind power. Based on the overview of the development of wind energy and combined with the current situation of wind power market, the development trends of wind turbine were discussed. It also proposed the problems which were existed in domestic wind power market.

Abstract: Smart Grid is the newest direction of electric power development, and is regarded as the significant technology innovation and development trend of the electric power system in 21st century. It is also regarded as the inevitable result of the development of economic and technology. It has flexible, clean, safe, economical, and friendly functions. Smart grid is a new "second generation" network, which is built on an integrated basis of two-way high-speed communication networks, through the application of advanced sensing and measurement techniques, equipment technology, control technology and decision support system technology in order to achieve reliable, safe, high-quality, economical, efficient, environmentally friendly and safe using target. Smart Grid’s background, significance key technologies, technical difficulties and prospects are introduced in this paper.

Abstract: A distribution system consists of all sorts of power distribution equipment, communication system and control equipment. It works according to certain rules to meet the demand of users by the high quality of electric energy . Distribution Automation (DA) can realize the automation of system operation and management to provide customers with stable, reliable electricity and obtain maximum benefits .This paper generally introduces the concept, function, developing future of Distribution Automation System. Distribution Automation includes feeder automation, automatic distribution management and user automation, and this paper introduces the basic situation and problems of them. Finally, it is concluded that Distribution Automation is the inevitable trend of Distribution System,and will be gradually developing in the direction of smart distribution grid.

Abstract: Wind power is a kind of special electric power, because of the volatility of the wind, making voltage stability has become an important research problem wind power system must facing with. Therefore, according to the relevant current research status and the main existent problems of wind power system, expounding the difference of voltage stability between the conventional energy sources and the wind power, and the influence of voltage stability to the power system which caused by wind power system. This paper mainly from the definition and the classification to introduce the voltage stability; from the research contents and methods of static and dynamic voltage stability to analyze power systems which contains wind farms, especially emphasizing the necessity of the bifurcation theory used in power system contains wind power. Finally points out that the research trend of analysis and improvement in this area.

Abstract: This paper reviews the development of static synchronous compensator (STATCOM), and analylizes the structure of its main circuit, its working principles and control strategies. At last, this paper comes to a conclusion of technical characteristics of STATCOM and outlook of its development trends. Fast acting STATCOM, a representative of FACTS family, is a promising technology which is extensively used as state-of-the-art dynamic shunt compensator for reactive power control in transmission and distribution system. STATCOM controller employs various solid-state converter topologies, magnetics configurations, control algorithms, and switching techniques and so on. The development of STATCOM controller has been well reported in literature with its versatile application in power system. Thus deep investigation of STATCOM from the perspective of its intelligent control and the configuration of STATCOM’s main circuit is valuable.

Abstract: Nowadays energy is the important foundation of modern national economic development. Electric power as the main form energy supply is very close to the national economy, the consumption of social power energy represents the development of modern society [2]. In recent years all countries in the world are seeking to develop alternative energy in actively, exploring the sustainable development of the energy strategy. The wind power is a renewable energy which can be used in large-scale, and this power is friendly to environmental and makes for sustainable development.

Abstract: The discussion of the paper will focus on the Smart Grid, mainly elaborate the fundamental concept, staple characteristic and the pivotal technology of the Smart Grid. The main method to discuss it is to do the research on the key techniques of the Smart Grid which consist of the advanced measurement system、the advanced power electronic equipments and the access to the renewable energy and the distributed energy, In addition, the paper introduce the development of the domestic and the abroad including the American 、European and China. As a result I put forward to the opportunities and challenges that the smart grid will face. I draw the conclusion that the utilization of the renewable energy will absolutely be a hot issue in the future and the smart grid will bring radical changes for human beings’ life.

Abstract: Doubly fed induction generator (DFIG) is receiving more attention nowadays due to growing power demand and environmental concerns. In this paper, five main issues of the DFIG associating with the grid-connection, low voltage ride-through (LVRT), maximum power point tracking (MPPT) control strategy, operation in unbalanced voltage condition, contribution to frequency regulation of grid and influence on power system stability are discussed.