Electrical Machines I. Basics, Design, Function, Operation by Gerhard Henneberger

By Gerhard Henneberger

Show description

Read Online or Download Electrical Machines I. Basics, Design, Function, Operation PDF

Similar technique books

Problems in Electrical Engineering

Excerpt from difficulties in electric EngineeringThis selection of difficulties has been ready for using scholars on the Massachusetts Institute of know-how, yet because the ebook can be utilized in different technical colleges it sort of feels top to nation what flooring the issues are meant to hide. on the Institute the e-book might be utilized by the 3rd yr scholars in electric Engineering, and via the 3rd and fourth 12 months scholars within the classes of Civil, Mechanical, Mining and Chem ical Engineering.

The Secrets of Building a Plastic Vacuum Forming Machine

Ebook by way of Gingery, Vincent R.

Extra info for Electrical Machines I. Basics, Design, Function, Operation

Example text

Example: Z1KST = short-circuit on secondary side Z 1K ∆Z K ∆Z K (w − w )2 = Z 1K = Z1 K 2 2 1 Z 1K + ∆Z K Z2K w2 = Z1K (1 − ü ) 2 For ü close to 1, the short-circuit current rises high! 143) 4 Fundamentals of rotating electrical machines Rotating electrical machines are electromechanical energy converters: motor – generator The described energy conversion, expressed as forces on the mechanical side, whereas it appears as induced voltages on the electrical side. Basically electrical machines can be operated in both motor- and generator mode.

75) R 1K I X jX 1K I1N 1k U 1K 1N ϕ U 1K K R 1K I1N I1N Fig. 38: phasor diagram Fig. 37: short-circuit ecd For a reasonable comparison of transformers of different sizes and power ratings, a variable called “relative short circuit voltages” is introduced. These are short circuit voltage values normalized to the nominal voltage. 3 Load with nominal stress Due to relations applied in real transformers R : Xσ : Xh : RFe ≈ 1 : 2 : 1000 : 10000, sufficient accuracy is reached with usage of the simplified ecd (shown in Fig.

Generator P el stator air gap rotor n Stator and rotor are usually fitted with windings, with voltages to be induced, caused by spatiotemporal flux alteration. Forces either appear as Lorentz force in conductors or as interfacial forces on (iron) core surfaces. motor P mech P mech generator v Fig. 64: scheme of energy conversion Technical demands on energy converters: 1. time independent constant torque (motor) and according constant power output (generator) in steady state operation 2. quick adjustment of torque and speed (motor) and according voltage and current (generator) in transient operation Electrical machines are usually supplied by either DC or AC systems.

Download PDF sample

Rated 4.01 of 5 – based on 8 votes