A permanent magnet DC servomotor with the following motor parameters: Torque Constant: Back EMF Constant: Armature Resistance: Armature Inductance: Viscous Damping: Friction Torque: KT KE RA LA FM TE 3.0 x 10-² 3.0 x 10-² 4.0 6.0 0 0 (N-m)/A (V.s)/rad Ω mH (N.m.s)/rad N-m a) What is the steady-state no-load speed in RPM for an input of 12V? b) What is the motor torque under stall conditions for an input of 12V? c) Assuming that the motor is driving a purely inertial load that is significantly greater than the rotor inertia. Which motor parameter can be neglected to arrive at a first-order transfer function? d) Assume that the motor is being used as a generator and that the motor shaft is rotating at 2000 rpm. What is the open-circuit voltage across the motor terminals?

A permanent-magnet dc motor hasRA = 1.0 Ω. With no load, it operatesat 1000 rpm and draws 1.0 A from a 15 Vsource. Assume that rotational power lossis proportional to speed. Find the outputpower and efficiency for a load that dropsthe speed to 950 rpm.

× 4:03 K s.eng.ruh.ac.lk □ Û 8. Figure 4 shows the core of a simple dc motor. The magnetization curve for the metal in this core is given by Figure 5 and Figure 6. Assume that the cross-sectional area of each air gap is 18 cm² and that the width of each air gap is 0.05 cm. The effective diameter of the rotor core is 4 cm. L It is desired to build a machine with as great a flux density as possible while avoiding excessive saturation in the core. What would be a reasonable maximum flux density for this core? ii. What would be the total flux in the core at the flux density of part (i)? iii. The maximum possible field current for this machine is I A. Select a reasonable number of turns of wire to provide the desired flux density while not exceeding the maximum available current. Flux Density, B (T) 2.8 སྤྲ ཤཱ ཀ ཀཱ བྷ ཀ ཡཱཾ བ ་ 1.2 1.0 0.4 0.2 4-48cm Figure 4 0 10 20 30 40 50 100 → Depth 4 cm -0.05 cm 200 300 500 1000 2000 Magnetizing Intensity, H (A.turns/m) Figure 5 Magnetization curve…