matlab英文论文

Transient Stability of a power system with SVC and PSS

包含SVC及PSS的电力系统暂态稳定性

Introduction

The example described in this section illustrates modeling of a simple transmission system containing two hydraulic power plants（本例为包含两个水电厂的简单传输系统）. A static var compensator (SVC) and power system stabilizers (PSS) are used to improve transient stability and power oscillation damping of the system（本系统使用静止无功补偿器和电力系统稳定器以提高暂态稳定性及振荡阻尼）. The power system illustrated in this example is quite simple. However, the phasor simulation method allows you to simulate more complex power grids. （虽然本例所示的电力系统非常简单，但是这种相量仿真方法仍然适用于更复杂电力网络的仿真）The single line diagram shown below represents a simple 500 kV transmission system. （简单500KV传输系统的单线图如下所示）

500 kV Transmission System

A 1000 MW hydraulic generation plant (M1) is connected to a load center through a long 500 kV, 700 km transmission line（一个1000MW水电厂M1通过500KV，长700公里的传输线与负荷中心相连）. The load center is modeled by a 5000 MW resistive load（负荷中心可采用

5000MW电阻性负载模拟）. The load is fed by the remote 1000 MVA plant and a local generation of 5000 MV A (plant M2)（负载通过远方1000 MV A电厂及当地5000MV A电厂供电）.A load flow has been performed on this system with plant M1 generating 950 MW so that plant M2 produces 4046 MW（负载所需功率由电厂M1提供950MW，因而电厂M2需产生4046MW功率）. The line carries 944 MW which is close to its surge impedance loading (SIL = 977 MW)（当线路传输944MW功率时很接近其自然功率（977MW））. To maintain system stability after faults, the transmission line is shunt compensated at its center by a 200 Mvar static var compensator (SVC). The SVC does not have a power oscillation damping (POD) unit（为了维持故障后系统稳定性，在线路中点处并联了200MV AR静止无功补偿器。SVC中不包含功率振荡阻尼单元）. The two machines are equipped with a hydraulic turbine and governor (HTG), excitation system, and power system stabilizer (PSS). （两台发电机组均含有水轮机调速器，励磁系统，电力系统稳定器）

This system is available in the power_svc_pss model（本系统可搭建为功率-SVC-PSS模型）. Load this model and save it in your working directory as case1.mdl to allow further modifications to the original system（存盘以备修改扩展）. This model is shown in Model of the Transmission System (power_svc_pss)

Model of the Transmission System (power_svc_pss)

First, look inside the two Turbine and Regulators subsystems to see how the HTG and the excitation system are implemented（首先看一下水轮机及调节子系统的内部结构以了解调速器和励磁系统的工作）. Two types of stabilizers can be connected on the excitation system: a generic model using the acceleration power (Pa= difference between mechanical power Pm and output electrical power Peo) and a Multiband stabilizer using the speed deviation (dw)（励磁系统可连接两种类型的稳定器：一种是使用加速功率（作为输入）的通用模型，另一种是使用速度偏差（作为输入）的多频段稳定器）. These two stabilizers are standard models of the powerlib/Machines library. Manual Switch blocks surrounded by a blue zone allow you to select the type of stabilizer used for both machines or put the PSS out of service.（这两种稳定器模型都是powerlib/Machines库中的标准模型。蓝色区域内的手动切换开关用来选择模型种类或者将PSS退出运行。）

The SVC is the phasor model from the FACTS library. Open its dialog box and check in the Power data parameters that the SVC rating is +/- 200 Mvar. In the Control parameters, you can select either V oltage regulation or Var control (Fixed susceptance Bref) mode. Initially the SVC is set in Var control mode with a susceptance Bref=0, which is equivalent to having the SVC out of service.

A Fault Breaker block is connected at bus B1. You will use it to program different types of faults on the 500 kV system and observe the impact of the PSS and SVC on system stability.

To start the simulation in steady-state, the machines and the regulators have been previously initialized by means of the Machine Initialization utility of the Powergui block. Load flow has been performed with machine M1 defined as a PV generation bus (V=13800 V, P=950 MW) and machine M2 defined as a swing bus (V=13800 V, 0 degrees). After the load flow has been solved, the reference mechanical powers and reference voltages for the two machines have been automatically updated in the two constant blocks connected at the HTG and excitation system inputs: Pref1=0.95 pu (950 MW), Vref1=1.0 pu; Pref2=0.8091 pu (4046 MW), Vref2=1.0 pu. Single-Phase Fault — Impact of PSS — No SVC

Verify that the PSSs (Generic Pa type) are in service and that a 6-cycle single-phase fault is