Second week notes

DC Motor

From 1821 Faraday found that the conductors flowing through the current are subject to magnetic force in the magnetic field, and a Rotary DC generator is made by the PIXII in 1831. Since then, scientists have focused on improving utilization, reducing volume, reducing energy consumption, and controlling precision. But DC motor has some inherent shortcomings, low voltage transmission loss, high-voltage DC motor manufacturing difficulties, single-machine capacity is difficult to achieve control, so people began to switch to AC motor.

DC Motor and DC drive system is also in some areas, especially in the field of large-scale motor, is operated, the maintenance of relatively convenient AC speed motor and AC speed control system replaced, the scope of application is declining trend. However, DC motor and can be decoupled to adjust the direct current transmission system after a long-term development, has accumulated rich experience in operation and maintenance. The AC speed regulating motor and the AC speed regulating system are considered. In a certain capacity range and some operating modes, there are also the technical and economic rationality of the system, some operating requirements and operating environment can not be separated from the DC system. Therefore, in a certain period, DC motor and DC drive system also has the development space, can not or should not be completely replaced.

AC Motor

The AC motor was invented by the Serbian-American scientist Nikola Tesla. From the material time of 1888, than the emergence of DC motor more than 50 years later, but due to the huge development of AC power system, AC motor has become the most commonly used motor. Compared with DC motor, AC motor, because there is no commutator (see DC Motor commutation), so the structure is simple, easy to manufacture, relatively firm, easy to make high speed, high voltage, large current, large capacity of the motor. AC motor Power covers a wide range from a few watts to hundreds of thousands of kw and even millions of kilowatts.

Code

Model Motor1

Real Tm;

Real N;

Real i;

Real u;

Parameter Real J = 0.02;

Parameter Real R = 0.2;

Parameter Real Kt = 1.5;

Parameter Real Ke = 0.8;

Parameter Real Tl = 2;

Equation

If time <= 0.1 Then

U = 50;

Else

u = 100;

End If;

TM-TL = J * der (n);

tm= Kt * i;

u= i * R + Ke * N;

End Motor1;

Simulate (motor1,starttime=0,stoptime=0.2)

Record Simulationresult

Resultfile = "Motor1_res.mat",

Messages = ""

End Simulationresult;

Omc-error:

"Warning:the initial conditions is not fully specified. Use the +d=initialization for more information.

"

Plot ({tm,n})

Plot (N)

Second week notes