学习内容：本周的话主要讲了三相异步电机和它的启动、调速、制动的方法。重点的话定子旋转磁场方向等判断，异步电机的人为机械特性分析。对这部分理解还不够深。课下又看了几遍，才敢做以下仿真。

仿真：

本次仿真任务如下：

1）实现如下机械运动周期：

控制电机带重物上升，从静止加速到800r/min
保持800r/min匀速运动0.5s，
减速到静止，保持静止状态0.5s，
带重物下降，从静止达到600r/min
保持600r/min匀速运动0.6s，
减速到静止。
(为了便于仿真，匀速和静止持续时间较短)

本次控制策略选择：

首先，经过长时间参数试验，得知一般的控制规律，再结合课本，开始进行控制。首先对这几段运动，按所需的评价指标修改，对于第一段启动，采用便捷的定子串电阻方法，可以降低冲击转矩和冲击电流，而启动时间的控制，便是常规处理计算频率，调频即可，另外用到电压调节，即用变频，变电压结合方法，以下均是该方法。 对于第一次制动，我们可以选择几个相对较低的频率降低制动时间，同时减小电压倍数来降低冲击转矩。以下几个启动制动过程均是该思想，经过反复试验，调节参数，找规律，可以拟合出电机带动重物升降的过程Tm,n的变化。

编写程序如下：

model SACIM "A Simple AC Induction Motor Model"

type Voltage=Real(unit="V");

type Current=Real(unit="A");

type Resistance=Real(unit="Ohm");

type Inductance=Real(unit="H");

type Speed=Real(unit="r/min");

type Torque=Real(unit="N.m");

type Inertia=Real(unit="kg.m^2");

type Frequency=Real(unit="Hz");

type Flux=Real(unit="Wb");

type Angle=Real(unit="rad");

type AngularVelocity=Real(unit="rad/s");

constant Real Pi = 3.1415926;

Current i_A"A Phase Current of Stator";

Current i_B"B Phase Current of Stator";

Current i_C"C Phase Current of Stator";

Voltage u_A"A Phase Voltage of Stator";

Voltage u_B"B Phase Voltage of Stator";

Voltage u_C"C Phase Voltage of Stator";

Current i_a"A Phase Current of Rotor";

Current i_b"B Phase Current of Rotor";

Current i_c"C Phase Current of Rotor";

Frequency f_s"Frequency of Stator";

Torque Tm"Torque of the Motor";

Speed n"Speed of the Motor";

Flux Psi_A"A Phase Flux-Linkage of Stator";

Flux Psi_B"B Phase Flux-Linkage of Stator";

Flux Psi_C"C Phase Flux-Linkage of Stator";

Flux Psi_a"a Phase Flux-Linkage of Rotor";

Flux Psi_b"b Phase Flux-Linkage of Rotor";

Flux Psi_c"c Phase Flux-Linkage of Rotor";

Angle phi"Electrical Angle of Rotor";

Angle phi_m"Mechnical Angle of Rotor";

AngularVelocity w"Angular Velocity of Rotor";

Torque Tl"Load Torque";

parameter Resistance Rs = 0.531"Stator Resistance";

parameter Resistance Rr = 0.408"Rotor Resistance";

parameter Inductance Ls = 0.00252"Stator Leakage Inductance";

parameter Inductance Lr = 0.00252"Rotor Leakage Inductance";

parameter Inductance Lm = 0.00847"Mutual Inductance";

parameter Frequency f_N = 26.77778 "Rated Frequency of Stator";

parameter Voltage u_N = 220"Rated Phase Voltage of Stator";

parameter Real p =2"number of pole pairs";

parameter Inertia Jm = 0.1"Motor Inertia";

parameter Inertia Jl = 1 "Load Inertia";

parameter Resistance R0 = 0.331"exception Resistance";

initial equation

Psi_A = 0;

Psi_B = 0;

Psi_C = 0;

Psi_a = 0;

Psi_b = 0;

Psi_c = 0;

phi = 0;

w = 0;

equation

u_A = (Rs+R0) * i_A + 1000 * der(Psi_A);

u_B = (Rs+R0) * i_B + 1000 * der(Psi_B);

u_C = (Rs+R0) * i_C + 1000 * der(Psi_C);

0 = Rr * i_a + 1000 * der(Psi_a);

0 = Rr * i_b + 1000 * der(Psi_b);

0 = Rr * i_c + 1000 * der(Psi_c);

Psi_A = (Lm+Ls)*i_A + (-0.5*Lm)*i_B + (-0.5*Lm)*i_C + (Lm*cos(phi))*i_a + (Lm*cos(phi+2*Pi/3))*i_b + (Lm*cos(phi-2*Pi/3))*i_c;

Psi_B = (-0.5*Lm)*i_A + (Lm+Ls)*i_B + (-0.5*Lm)*i_C + (Lm*cos(phi-2*Pi/3))*i_a + (Lm*cos(phi))*i_b + (Lm*cos(phi+2*Pi/3))*i_c;

Psi_C = (-0.5*Lm)*i_A + (-0.5*Lm)*i_B + (Lm+Ls)*i_C + (Lm*cos(phi+2*Pi/3))*i_a + (Lm*cos(phi-2*Pi/3))*i_b + (Lm*cos(phi))*i_c;

Psi_a = (Lm*cos(phi))*i_A + (Lm*cos(phi-2*Pi/3))*i_B + (Lm*cos(phi+2*Pi/3))*i_C + (Lm+Lr)*i_a + (-0.5*Lm)*i_b + (-0.5*Lm)*i_c;

Psi_b = (Lm*cos(phi+2*Pi/3))*i_A + (Lm*cos(phi))*i_B + (Lm*cos(phi-2*Pi/3))*i_C + (-0.5*Lm)*i_a + (Lm+Lr)*i_b + (-0.5*Lm)*i_c;

Psi_c = (Lm*cos(phi-2*Pi/3))*i_A + (Lm*cos(phi+2*Pi/3))*i_B + (Lm*cos(phi))*i_C + (-0.5*Lm)*i_a + (-0.5*Lm)*i_b + (Lm+Lr)*i_c;

Tm =-p*Lm*((i_A*i_a+i_B*i_b+i_C*i_c)*sin(phi)+(i_A*i_b+i_B*i_c+i_C*i_a)*sin(phi+2*Pi/3)+(i_A*i_c+i_B*i_a+i_C*i_b)*sin(phi-2*Pi/3));

w = 1000 * der(phi_m);

phi_m = phi/p;

n= w*60/(2*Pi);

Tm-Tl = (Jm+Jl) * 1000 * der(w);

if time <= 100 then

u_A = 0;

u_B = 0;

u_C = 0;

f_s = 0;

Tl = 0;

elseif time <= 797 then

f_s = f_N;

u_A = u_N * 1.100 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 1.100 * sin(2*Pi*f_s*time/1000-2*Pi/3);

u_C = u_N * 1.100 * sin(2*Pi*f_s*time/1000-4*Pi/3);

Tl = 15;

elseif time <= 1297 then

f_s = f_N;

u_A = u_N * 1.100 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 1.100 * sin(2*Pi*f_s*time/1000-2*Pi/3);

u_C = u_N * 1.100 * sin(2*Pi*f_s*time/1000-4*Pi/3);

Tl = 15;

elseif time <= 1337 then

f_s = 15;

u_A = u_N * 0.5 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 0.5 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 0.5 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <=1367 then

f_s = 18;

u_A = u_N * 0.5 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 0.5 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 0.5 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <=1821 then

f_s = 20;

u_A = u_N * 1.100 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 1.100 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 1.100 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <=2321 then

u_A = 0;

u_B = 0;

u_C = 0;

f_s = 0;

Tl = 0;

elseif time <= 2341 then

f_s=115;

u_A = u_N * 0.5 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 0.5 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 0.5 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <= 2361 then

f_s=40;

u_A = u_N * 0.5 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 0.5 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 0.5 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <= 2719 then

f_s=20;

u_A = u_N * 1.0 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 1.0 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 1.0 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <= 3319 then

f_s = 20;

u_A = u_N * 1.0 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 1.0 * sin(2*Pi*f_s*time/1000-4*Pi/3);

u_C = u_N * 1.0 * sin(2*Pi*f_s*time/1000-2*Pi/3);

Tl = 15;

elseif time <=3384 then

f_s = 30;

u_A = u_N * 0.3 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 0.3 * sin(2*Pi*f_s*time/1000-2*Pi/3);

u_C = u_N * 0.3 * sin(2*Pi*f_s*time/1000-4*Pi/3);

Tl = 15;

elseif time <=3873 then

f_s = 20;

u_A = u_N * 1.0 * sin(2*Pi*f_s*time/1000);

u_B = u_N * 1.0 * sin(2*Pi*f_s*time/1000-2*Pi/3);

u_C = u_N * 1.0 * sin(2*Pi*f_s*time/1000-4*Pi/3);

Tl = 15;

else

u_A = 0;

u_B = 0;

u_C = 0;

f_s = 0;

Tl = 0;

end if;

end SACIM;