Consider the case in which the load on the synchronous Consider the case in which the load on the synchronous motor in the field oriented torque-control system of Problem 11.13 is increased, and the motor begins to slow down. Based upon some knowledge of the load characteristic, it is determined that it will be necessary […]
The motor of Problem 5.5 is supplied from a 460-V, three-phase The motor of Problem 5.5 is supplied from a 460-V, three-phase source through a feeder whose impedance is Zf = 0.084 + j0.82?. Assuming the system (as measured at the source) to be operating at an input power of 40 kW, calculate the magnitude […]
The magnetic circuit of Problem 1.1 has a nonlinear core The magnetic circuit of Problem 1.1 has a nonlinear core material whose permeability as a function of Bm is given by where Bm is the material flux density. a. Using MATLAB, plot a dc magnetization curve for this material (Bm vs. Hm) over the range […]
The magnetic circuit of figure has two windings and two The magnetic circuit of figure has two windings and two air gaps. The core can be assumed to be of infinite permeability. The core dimensions are indicated in the figure. a. Assuming coil 1 to be carrying a current Il and the current in coil […]
The manufacturer’s data sheet for a 26-kV, 750-MVA 60-Hz three-p The manufacturer’s data sheet for a 26-kV, 750-MVA 60-Hz three-phase synchronous generator indicates that it has a synchronous reactance Xs = 2.04 and a leakage reactance Xal = 0.18, both in per unit on the generator base. Calculate (a) The synchronous inductance in mH, (b) […]
The linear-motor armature of Problem 4.25 has a total active The linear-motor armature of Problem 4.25 has a total active length of 7 wavelengths, with a total of 280 turns per phase with a winding factor kw = 0.91. For an air-gap length of 0.93 cm, calculate the rms magnitude of the balanced three-phase currents […]
The inductor of Problem 1.13 is to be operated fro The inductor of Problem 1.13 is to be operated from a 60-Hz voltage source. (a) Assuming negligible coil resistance, calculate the rms inductor voltage corresponding to a peak core flux density of 1.5 T. (b) Under this operating condition, calculate the rms current and the […]
The magnetic circuit of figure and Problem 1.6 has the The magnetic circuit of figure and Problem 1.6 has the following dimensions: Ac = 8.2cm2 lc = 23cm lp = 2.8 cm g = 0.8 mm X0 = 2.5 cm N = 430 turns a. Assuming a constant permeability of Âľ = 2800Âľ0, calculate the […]
Consider the dc-motor drive system of Problem 10.13. To limit Consider the dc-motor drive system of Problem 10.13. To limit the starting current of the dc motor to twice its rated value, a controller will be used to adjust the initial firing-delay angle of the SCR Bridge. Calculate the required firing-delay angle Îąd.
The inductor of figure has the following dimensions The inductor of figure has the following dimensions: Ac = 1.0 cm2 lc = 15 cm g = 0.8 mm N = 480 turns Neglecting leakage and fringing and assuming Âľr = 1000, calculate the inductance.