power_smstarting matlab simulink 电子电器仿真模型 源文件.zip

%% Starting a Synchronous Motor % % This example shows the starting procedure for a synchronous motor. % % Richard Gagnon (Hydro-Quebec) % Copyright 1997-2012 Hydro-Quebec, and The MathWorks, Inc. %% open_system('power_smstarting') %% Description % % When a synchronous motor is started, the excitation DC voltage is not applied to the field winding. % The motor is started in induction machine mode with currents induced in the damper and field windings. % A resistor is connected across the field winding in order to produce an acceptable field current and to limit voltage induced across the field winding. % Then when speed reaches a preset value near synchronous speed, the field winding is connected to the DC voltage source % and the motor synchronizes on the system frequency. % % In the synchronous machine model, the field winding terminals are not available. Instead, a Simulink(R) signal representing the field voltage must be applied at % the Vf input of the machine. Therefore if the Vf input is left unconnected, a zero field voltage is applied on the rotor. In other words, the field winding is % short-circuited. In this example, the field current (idf) and a gain block (R_start) are used to implement the resistance connected across the field winding. % % This model illustrates the starting prodcedure of a 60-kVA 400-V 50Hz synchronous motor. The motor is started at no load by closing the circuit breaker at t=0.1s . % A 2 pu resistor is initially connected across the field winding. % When the rotor speed reaches 0.99 pu, the "R_start" resistor is disconnected from the field terminals and it is replaced by the "Vf source" (1 pu). % At the same time, the mechanical power is ramped from zero to 50% of the nominal mechanical power (Pm = -0.5 pu) in one second. % The motor locks into step at synchronous speed (1 pu) at approximately t = 1.3 s. % %% clear all close all bdclose all