Youjie Ma

The dynamic modeling of wind farms considering wake effects and its optimal distribution

Under the four-component wind speed model, the wind turbine output power was researched based on the Jensen wake model, which combined of the dynamic wind turbine model; anglicizing with the distribution of wind power from the theoretical, optimization method that named quadratic interpolation was used, and the optimization tool of Matlab\simulink verified that the correct conclusion has a certain rationality. Rational arrangement of wind turbine in order to minimize wake effects, so that the output of wind power can be improved, the study of optimal operation of wind farms and planning issues related to be a certain value.

Grid-Connected Control and Simulation of Single-Phase Two-Level Photovoltaic Power Generation System Based on Repetitive Control

A further research on Grid-connected photovoltaic system was made in this paper. The author made a design for the control of single-phase two-level photovoltaic power generation system based on Repetitive control. In order to achieve a precise control to the Grid-current, the maximum power point tracking and the Grid-connected Inverter`s control were realized respectively. Finally, the whole design for the Grid-connected photovoltaic system has been verified through simulating with the help of MATLAB software. A set of experimental results carried out on a computer is provided to validate the proposed approach. All the work done was of great significance on the development of Grid-connected PV system.

STATCOM control research and analysis

Through the Introduction of presentation structure and basic functions of a static synchronous compensator (STATCOM) controller, analysis of Reactive Power Compensation Control Method is introduced as an example for inhibit voltage flicker, oscillation damping system, excellent dynamic qualities of power system normal state transition process and the improvement of power system transient, static stability limit. Advantages and disadvantages of various methods are summed up and the future trends of the prospects are proposed in the last.

Key technologies of smart distribution grid

In order to build a strong smart grid with Chinese characteristics, the smart distribution grid issue is studied. Some present questions hindering the futuristic development of electric power distribution are proposed. The definition of smart distribution grid is given. The detailed characteristics are analysed in the paper, several functional requirements are put forward, and the development in the corresponding field is reviewed. The key technologies deployed for the realization of the smart distribution grid are explored in depth, which would give advice for the further research and implementation of distribution network intellectualization in the future. By incorporating with new technologies like Big Data and Internet of Things, SDG is prone to obtain a new opportunity to develop.

Research of control technology in grid-connected photovoltaic power system

Grid-connected photovoltaic power system is not only related to solar battery and grid inverter technology, but also involves the system control and optimization problem. The research and improvement about control technology play a vital role in improving the efficiency of the system and Realizing optimization grid. On the basis of considering about control requirements in grid-connected photovoltaic power system, the paper analyzes comprehensively the control technology about MPPT, grid of inverter and island detection. At last, the paper points out the research hotspots and development trend in each part.

A new maximum power point tracking method for PV system

Maximum power point tracking (MPPT) technique is used in photovoltaic (PV) power generation system to assume the maximum power point (MPP) no matter how the PV panel temperature and irradiation conditions change. It plays a decisive role in PV power generation system. Therefore, this paper introduces a modified optimal voltage control (OVC) method coupled with active disturbance rejection control (ADRC) algorithm. The proposed method focuses on parameter optimization corresponding to variable panel temperature and irradiation conditions. The results, comparing with OVC method, show that the proposed method improves power tracking speed and efficiency of energy conversion simultaneously. Finally, through the simulation by MATLAB/SIMULINK platform, we verify the feasibility and effectiveness of the proposed method.

The discussion on static synchronous compensator technology

Reactive power balance plays an essential role in improving economic efficiency and grid power quality. With the rapid development of power industry, high pressure and high voltage power grid have been put into operation, quality and reliability of the electric power have become increasingly demanding, as well as the reactive power compensation equipment. STAT COM device is currently the optimal performance of the reactive power compensation devices. Static synchronous compensators (STATCOMs) are part of FACTS device lineage. Their primary aim is to provide a fast acting, precise, and adjustable quantity of reactive power to an AC power system network to which they are linked. This article will focuse on the background, significance, research status, several key technologies and development issues. STATCOM mainly involves several key technologies: inverter power electronic devices; topology structure of the main circuit.; pulse width modulation.; control strategy; reactive current detection. With the economic development, the traditional large capacity STATCOM application occasions gradually restricted and therefore, in the future development of key technologies STATCOM must constantly improve to meet current requirements. In response to these key technical problems and make recommendations to improve these problems.

Analyze on Dynamic Frequency Characteristic of Industrial Electric Power Network under Power Situation when External Faults Occur

The dynamic frequency characteristics of industrial electric power network is Analyzed when external faults occurs. It reveals the active power gap, adjusting effect parameters and other related factors how to affect the frequency. Appropriate model is build about Tianjin Sinopec Company. Power transition process under external faults is simulated by PSASP. It proves the correctness of the conclusions. Above all, it is good for taking measures to ease lowering speed of frequency, change the steady-state value of frequency, and improving the safety and stability of industrial electric power network.

Research Review on the Smart Distribution Grid

Smart distribution grid (SDG) is the focus of the future smart grid construction, it will have a profound impact on the operation of power system protection and control. In this paper, the concept and characteristics of SDG are systematically introduced, then brief introduce SDG background, significance, as well as overseas and domestic research status. The key technologies of SDG are discussed, including the distribution network self-healing control (SHC), distribution fast simulation and modeling (DFSM), advanced distribution automation (ADA), advanced metering infrastructure (AMI), active distribution network (ADN), distributed generation (DG) and smart micro grid technology. Combined with the current situation of smart distribution grid, it points the development tendency of SDG.

The research on energy conservation controller for asynchronous motor based on ADRC

Asynchronous motors are widely applied in industry, agriculture production and daily life, but in practical application, asynchronous motor often works in empty or light load because of various factors, leading to a low power factor and efficiency, which cause a great waste of energy. Therefore, it is of important practical significance to research of asynchronous motor energy conservation issue. This paper analyzes the energy-saving principle of asynchronous motor, mainly studies under the condition of light load or no load, according to a certain control rules to reduce the motor input voltage to achieve energy saving purposes. ADRC(Active Disturbance Rejection Control) technology is proposed to achieve energy-saving, and use the MATLAB simulation software to study the control system of energy-saving.