A Separately Excited DC Machine was subjected to a locked rotor test and a no-load test....
Please explain the no-load characteristics for shunt and separately excited DC motors. How will rotor speed, armature current and field current be effected for both at no load?
2) A 460 V, 4-pole, 60 Hz, Y-connected, 40 hp, design class A induction motor is tested with the following results: No-load: 460 V, 8.7 A, 2500 W. 60 Hz Locked rotor: 42 V.48 A, 31 10 W. 12 Hz DC test: 24 V, 48 A Find the equivalent circuit of this motor (Ri, Ro. Xi. X. XM) and its rotational losses. (20 points) X, and A2 as functions of XL Retor Design Wound rotor Design A Design B Design...
DC-DC Converter Machine Drives D QUE D EA TI C+ ata at I A separately excited DC motor is powered by a full bridge power converter using MOSFET power transistors and freewheeling diodes as shown above, Converter: Vs - 250 V Switching frequency - 5 kHz. Two-quadrant mode: Q3 always open and Q4 always closed. Assume ideal switches and diodes. DC machine: R-50 m2 LA = 300 H Ex -0.2 V/(r/min) Ignore rotational losses and brush voltage drop Answer the...
Problem 2 (10 points): A 3-phase, 208-V (H), six-pole Y-connected, 25-hp, design class B (X,-15%) induction motor is tested in the laboratory, with the following results: DC test: 13.5 V, 64 A No load: 208 V, 24.0 A, 1400 W, 60 Hz Locked rotor: 24.6 V, 64.5 A, 2200 W, 15 Hz Neglecting the core losses (a) Find the equivalent circuit parameters of this motor and show them on the equivalent circuit. (b) What is the rotational losses of this...
We have a separately excited dc machine with Vf=50, rf=25, lf=10, laf=2, ra=1, la=0.1, J=0.5, B=0.6 which is connected to a load with J=0.5 and B=0.4. If we connect 100 volts to the armature, what is the dynamical response of the system in time domain? Don't worry about units
Problem 2 A separately excited DC motor is characterized by the followng intormation Armature resistance Ra-5 2 armature inductance La . very large, Field resistance RS200 Ω, ted voltage Vt 200 V, and an inertia constant J-12 kg m Neglecting friction losses and assuming no-saturation in the machine magnetic core system, answer the folowing questions: Part 1: (6 marks) he motor a as shown in figure 2a. The motor drives a constant power load of vaue 1 40375 hp (ie...
Example 6C:
15. Calculate the actual rotor speed, in rad/s, at maximum steady-state torque for the machine given in Example 6C for operation as a motor when connected to an electric source of (a) 120 Hz with twice rated voltage, (b) 60 Hz with rated voltage, (c) 30 Hz with one-half rated voltage, and (d) 6 Hz with 10 percent rated voltage. Example 6C. The parameters for the equivalent circuit shown in Fig. 6.8-1 may be calculated by using electromagnetie...
A separately excited DC motor has the following data P=32kW (rated power); Va=220V (rated voltage); Ia=171A (rated curent); n=1000 rpm (rated speed); Ra = 0.096 ohm a.Calculate the armature voltage to reduce the speed to 900 rpm, assuming the load torque is kept constant? b.Calculate the resistance should be added to armature circuit to reduce the speed to 800 rpm, assuming the load torque is kept constant? c.Calculate the reduction of magnetic flux to reach the speed of 1100 rpm,...
3ELEC 3600. Problem H8 3-phase Wound Rotor Induction Motor This sheet is page 1. Number all pages. Consider the following induction machine THREE-PHASE INDUCTION MOTOR DATA* Ratings Line Voltage 2400 V; 72.17 A; Horsepower-300 hp stator frequency60 Hz Design W Poles -4; **Equivalent Circuit Values (in stator ohms Rated Freq)** R1 0.30000 R2'- 0.47159 X2'-1.73000; Jm2.5000 kg-m sq Thevenin Equivalent Circuit Values: RT-0.28524; slip, speed for max Torque0.1375; Rotational Loss Torque-TRL 0.18689 x (speed in rad/s) Nm X1 -1.73000 Xm67.740...