An amplidyne is an electromechanical amplifier with the characteristics of a rotating machine. It was invented prior to the second world war by Ernst Alexanderson. An amplidyne is a special-purpose DC generator. It comprises an electric motor that turns a …
In this post, we will look at the voltage and power equation of a dc motor and the condition for maximum power in a dc motor. Voltage Equation of a DC Motor The voltage V applied across the motor armature …
1. A shunt generator delivers 450 A at 230 V and the resistance of the shunt field and armature are 50 Ω and 0.03 Ω respectively. Calculate the generated e.m.f? Solution: The Generator Circuit is as shown in the figure, …
The machine which produces 3 phase power from mechanical power is called an alternator or synchronous generator. The working of an alternator is based on the principle that when the flux linking a conductor changes, an emf is induced in the …
Swinburne’s test is the simplest indirect method of testing dc machines. In this method, the dc machine (generator or motor) is run as a motor at no-load and losses of the machine are determined. Once the losses of the machine …
There are several tests that are conducted for testing a dc machine (generator or motor) to judge its performance. The most important performance tests to be conducted on the dc machine are: The magnetization or open-circuit test. The load characteristic. …
What is Back EMF? When the armature of a DC motor rotates under the influence of the driving torque, the armature conductors move through the magnetic field and hence emf is induced in them as in a generator. The induced emf acts …
Compensating Windings and Interpoles are one of the important step taken to minimize the undesirable effect of armature reaction in dc machines. Armature reaction causes many undesirable effects on a DC machine such as sparking on brushes. So, necessary steps …
In a DC power plant, power is usually supplied from several generators of small ratings connected in parallel instead of from one large generator. This is due to the following reasons: 1. Continuity of service If a single large generator …