为解决含移动应急电源(mobile emergency generators,MEG)的主动配电网故障恢复问题,建立了配电网恢复效益函数,基于启发式算法,给出了一种配电网恢复效益最大化控制策略.为验证所提控制策略的可行性,以改进的IEEE 70 节点系统为例,开展了仿真对比分析与算法验证,仿真结果表明,采用提出的MEG接入优化策略,MEG恢复效益指标优化了每个MEG接入点接入的MEG台数;采用基于启发式算法的配电网恢复效益最大化控制策略,恢复负荷和恢复路径指标提高了配电网恢复效益.

The output of photovoltaic power supply has randomness and uncertainty. When the power system is faced with large-scale distributed photovoltaic power supply access, there are disadvantages such as cumbersome scheduling process, poor power quality and high control cost. Cluster division provides a new way to deal with large-scale distributed photovoltaic units. In order to improve the operation efficiency and reliability of power system, the clustering method of distributed photovoltaic power supply is studied in this paper. First, by analyzing the relevant characteristics of the power supply and load of the access distributed photovoltaic power generation cluster, considering the electrical distance characteristics between nodes, the active and reactive power regulation capacity of photovoltaic power supply and the net load of nodes are selected as the cluster division index. Secondly, the improved K-medoids algorithm is adopted to iteratively select the center point, and the sample points around the center point are selected as the new center point. The sensitivity to isolated points is eliminated, and the distributed photovoltaic power supply is divided into efficient clusters. Finally, a practical example is given to verify that the proposed method can cluster photovoltaic power stations in different scenarios effectively, and a reasonable cluster division result is obtained.

受到调频死区影响,导致电网调频出现较大偏差.面对该情况,提出了基于多Agent的储能参与电网一次调频控制.依据基于多Agent调频控制原理,利用储能装置描述储能越限区域和调频死区.采用虚拟惯性控制,构建电网一次调频仿真模型.计算调节速度,确定频率偏差与负荷扰动之间的关系.设置区域控制误差信号,确定储能控制误差信号和频率偏差域,并设计电网一次调频控制流程.由实验结果可知,该方法在极端扰动场景和连续扰动场景下,频率偏差都低于0.020 Hz,为储能控制提供了技术支持.

针对大规模光伏并网输出稳定性和功率增益不好的问题,提出基于暂态稳定功率补偿控制的大规模光伏并网功率多源协调控制方法.采用多参量融合配置的方法进行大规模光伏并网功率多源协调参数采样和信息融合处理,根据光伏并网直流侧输入参数因素进行的静态极限有功功率调节,计算大规模光伏并网功率的稳态增益,采用静态极限电流调节的方法,构建大规模光伏并网功率调节的反馈补偿模型.在有功功率控制环路中通过暂态性稳定功率调节的方法,实现大规模光伏并网功率多源协调控制优化设计.测试结果表明,采用该方法进行大规模光伏并网功率多源协调控制的输出稳定性较高,有功功率平衡性较好,提高了多源协调控制的鲁棒性和自适应性.

阐述大规模可再生能源接入、市场交易等因素对特高压互联电网中多类电源实时互补有功控制的要求;对多类电源实时互补有功控制优化方法涉及的各主要环节进行分析,提出释放发电、输电计划可调空间,并在线计算输电断面最大输电能力(TTC)以充分利用电网的输电能力。以分调-省调两级调度为例,提出多类电源实时互补有功控制技术框架,强调兼顾可再生能源最大化消纳与其它电源调整的经济代价,强调运行约束、安全约束、市场交易约束和调度公平性约束的统筹考虑,兼顾经济性、安全性和"三公"调度的需求。

This paper analyses the mechanism of large scale cascading trip-off failures of wind turbine generators in China, focuses on the reasons of trip-off caused by overvoltage. It analyses the model of Doubly Fed Induction Generation (DFIG) and builds a model of a wind farm that is composed of Doubly Fed Induction generators in DIgSILENT. The wind farm A with capacity of 175MW and wind farm B with capacity of 175MW is accessed to the nine bus system. The simulation reproduces the processes of the cascading trip-off of wind turbine generators caused by undervoltage and overvoltage. The trip-off caused by undervoltage is due to the lack of Low Voltage Ride Through (LVRT). And that the capacitive reactive power compensation device is not timely removed leads to a large surplus of reactive power, then the voltage rises, so the wind turbine generators trip off because of overvoltage. By setting the contrast scenario, the result shows that if capacitive reactive power compensation device is promptly removed after the loss of a large amount of active power, the wind turbine generators will not trip off because of overvoltage.

This paper analyzes the necessity to carry out a large grid system closed-loop simulation test using real-time digital simulator (RTDS).Using RTDS with highly parallel computing power, scalability and high simulation precision, a closed-loop verification program of Wide Area Monitoring Analysis Protection-control system (referred to WARMAP system) based on RTDS and DNP protocol is put forwarded. The RTDS system and WARMAP system to achieve real-time data exchange between each system by adding information control station. The data communicate between systems follow DNP3.0 Protocol. This paper describes the program structure, the design of the hardware connections and experiment design method detailed. The test results show that the program can not only greatly increase the flexibility of the system on the basis of ensuring the data accurate, but also shorten the WARMAP system development cycle. The program has been implemented in the State Grid Electric Power Research Institute Power System security and stability analysis and Control Laboratory.

An experimental platform of wind turbine simulator is designed for the research of wind turbine power generation in laboratory environment.The operating principle of wind turbine is analyzed and the output characteristics of wind turbine are imitated by controlling the armature current of BLDCM(Brushless DC Motor).A static and dynamic model of fixed-pitch wind turbine is established and a high-precision torque close-loop control scheme is developed.The torque compensation strategy is simulated in MATLAB / Simulink environment under constant and variable wind speed conditions and the results show that the operating characteristics of wind turbine are accurately imitated.A wind turbine imitation system composed of PC,RT-LAB,DSP controller and BLDCM is constructed and the experimental results for different wind speeds verify the feasibility of the proposed wind turbine imitation scheme based on torque closed-loop control.

The Wide-Area Monitoring Analysis Protection Control System (WARMAP) is used for security and stability analysis and anti-accident measure in system development process in large-scale AC/DC parallel power grid. However, the WARMAP system should collect the required data from the Energy Management System (EMS) for calculation that not only increased the flexibility of the system but also extend the system development cycle. RTDS has wide application prospects in operation analysis, online stability analysis and decision of large-scale AC/DC parallel grid, because of parallel computing ability and expansibility. In RTDS an accurate model can be built, simulation data that is close to actual status of the power network operation can be obtained. By digital communication, the data from simulation is uploading to WARMAP system for Analysis and calculation, so that ensures the data accurateness and increases the portability, at the same time system development cycle is reduced.

In order to research wind turbine (WT) power generation in laboratory conditions, which do not have wind field environment, the power generation has to be imitated. This paper analyzes the operation principle of the WT, model the torque characteristics of WT by controlling the armature current of brushless DC motor (BLDCM). Then establish a strategy and dynamic model for the fixed-pitch wind turbine, developed a high precision closed-loop torque control scheme. At last, the whole wind turbine imitation system is performed, which includes PC, RT-LAB, DSP Controller and BLDCM; the experiments are conducted under wind mutation and wind Speed pulse. The experimental results verify the feasibility of the wind turbine imitation scheme based on torque closed-loop control.

A novel wind turbine emulator (WTE) based on a torque controlled Brushless DC (BLDC) motor is presented, which can emulate the steady-state and dynamic characteristics of an actual wind turbine. Variable wind speeds, turbine inertia and torque oscillation caused by tower shadow and wind shear are all considered in the construction of the actual wind turbine model and the torque controlled BLDC model . A PI regulator is employed to make sure that the output torque of BLDC tracks the reference torque. The simulation results based on RT-LAB real-time simulation platform verify the validity of the proposed WTE.