2 Content Introduction Elementary DC machine Voltage and Torque EquationsBasic Type DC MachinesDynamics characteristics of Magnet Permanent and Shunt DC Motor
3 Introduction DC machines application not widely used DC generator is replaced by rectifierDC Motor is still used in lower power :Shunt DC MotorPermanent Magnet DC MotorBrushless DC motor becomes popular and widely used in electric vehicle.
4 Elementary of DC Machine Stator coil as field winding source of fluxRotor coil as armature
5 Voltage Equation Voltage equation for field winding and rotor coil Flux linkage :Mutual inductance winding between field winding and armature as a function of Θr :Θr = 0, π, 2 π,L= Constant
7 DC Machine with paralel winding outA and a rotor coil
8 Comutation of DC Machine with permanent magnet Constant flux is established by magnet permanentSmall dc motor with low power control application
9 Voltage Equation Voltage field and coil winding is rotor speed is referred as back emf
10 Torque Equation Electromagnetic torque Torque and rotor speed equation :J = inertia of the rotor (kg m2 or Js2 )TL = mechanical loadBm = mechanical damping ratio (Nms)Te is positive in direction of θr and direction of TL opposes of Te
11 Basic Type of DC Machine (1) Separate WindingShunt DC Machine
21 System Equation :x = state vectoru = input vector
22 Example For control Design to express transfer functions between state and input variables. To derive transfer function between state variables (ia and ωr) and input variables (ia and TL).Inertia time constantSecond order differential equation in term of ωr:Coefficient of dumping ratio
24 DC shunt Motor Constant Torque Parameter :Vt (rated)= 120 V ; Ia (rated) = 10 A ; n = 1200 rpm ; If = 1,6 ARa = 0.5 Ω La = 0.01HRf = 75 Ω Lf = 0.02 HMechanical Load = 50 NTypical loads include belt conveyors with a fixed loading, extruders, hoists, and mine lifts.