This paper presents an identification method based on the iterative Prony to identify transfer function and configure PSS parameters using residue way. The iterative Prony is a very useful method to acquire power system oscillation modes, by which the system eigenvalue, oscillation frequency, amplitude, damping and relative phase can be directly estimated using the response of given input signals. Considering the influence of input signal on output signal, the iterative Prony can acquire the transfer function of power system, then, according to the corresponding residues we conducted coordinated setting of power system stabilizer (PSS) by residue method. The simulation results for two testing system examples prove that this proposal method is effective in the power system oscillation mode analysis and parameters determination of PSS, can improve eigenvalues of system and can enhance system damping after PSSs whose parameters are optimized by above method are built into power system

Iterative Prony Method Based Power System Low Frequency Oscillation Mode Analysis and PSS Design

Summary

In this paper, a general Transient Stability Estimation Index (TSEI) is introduced, which can be used in different network without any data training step. The TSEI determines the stability status based on quantifying the impact of parameters, which affect transient stability problem. To quantify the parameters, some networks are simulated off-line, and these parameters are randomly changed in their typical range. Then, the impact of these parameters is analyzed using critical clearing time of simulated short circuits. In this paper, IEEE 14-bus and New England 39-bus networks are used to provide off-line learning sets. Unlike the previous works which have used decision tree algorithm as a direct security assessment tool, here, decision tree is used for analyzing of the parameters impact. To validate the result of the data processing, they are compared with the classical transient stability solution. Then, the TSEI is proposed, which draws significantly low processing burden, which is suitable for online transient stability assessment. To test the generality of the proposed index, IEEE 162-bus network is used without any previous training data. In a real power system, using wide area measurements, first the required parameters are measured or estimated, and then the proposed TSEI is calculated for large disturbances. Simulation results show that the proposed index can acceptably estimate the stability, even in new networks. Copyright © 2014 John Wiley & Sons, Ltd.

General prefault transient stability estimation index using wide area phasor measurements

AVR fuzzy PID control system based on MCU

With the continuous development of distributed generation, electric vehicles, other new energy sources, and the operation of power system will inevitably be affected. The load modeling research under the condition of large-scale access to new energy is the basic work of power grid planning, design and operation scheduling control. In this paper, the principle and methods of load modeling are briefly described. Aiming at the problems of large-scale access of new energy to distribution network, the existing load modeling methods are introduced. The unsolved issues in this field and future research direction are also pointed out, which can provide some references for researchers engaged in load modeling.

Summary of Load Modeling Methods Considering Distributed Generation

Wide area measurement system (WAMS) has been widely used in power system dynamic monitoring and control, such as low frequency identification and control, stability assessment and preventive control, etc. However, as a measurement tool, Phasor Measurement Unit (PMU) has the measurement error and bad data unavoidably. If the raw measurements are applied in power system analysis and control directly, the unexpected consequence might be resulted in. Aiming at this problem, a novel dynamic state estimator for generator state variables is proposed in this paper. The corresponding mathematical model is given in detail. Bad data detection and elimination approach is presented as well. The simulation results show that the proposed method can provide the estimated trajectories of the generators in real-time, which eliminates the impact of measurement error and bad data and could give the backbone for WAMS based dynamic applications and real-time control.

Dynamic state estimator with Phasor measurements for power system electromechanical transient process

Mathematical models of power system elements are fundamental to power system studies such as planning, design, operation and control. It is necessary to improve the accuracy of power system simulation by means of identification techniques to obtain more realistic parameters of the elements in real power systems. In this paper, field tests to obtain the parameters and field tests to validate the models and their parameters are briefly described with emphasis on the comparison of test and simulation results. Transient stability studies show that the dynamic characteristics of power systems can be more exactly represented by using the models and parameters obtained from field test data. They also show that the total power output of the concerned power plant can be increased by 4-6 percent. Thus the economic benefit is considerable. >

The parameter identification of power system and its application for transient stability analysis

The excitation system parameters of large synchronous generators have great effects on power system stability studies. It is pointed out in this paper that by using the excitation system parameters identified from the field data by means of modern identification technology can represent the actual responses of the excitation system more accurately. Therefore, it is necessary to adopt the parameters identified from the field data in real power system stability studies. The comparison results of three kinds of excitation system models, i.e. the electromagnetic force E/sub q//sup '/ constant model, typical parameter model, and real model identified from field data, are also presented. The results demonstrate that the adjusting effects may be exaggerated by using the E/sub q//sup '/ constant model in power system stability studies to represent the conventional excitation system with time constant t=0.5", conceal the stability risk, while for fast response excitation system, the transient stability limits may be reduced by using E/sub q//sup '/ constant model, and thus conceal the potential of stability limits. The optimization of the excitation system parameters and their effects on power system transient stability studies are also given in this paper.

Jiang Jianmin

Papers

The parameter identification of power system and its application for transient stability analysis

Effects of the excitation system parameters on power system transient stability studies