In a dc machine, the given input energy will be not equal to output energy i.e., the output energy will be always less than the input energy, thereby reducing the efficiency. The whole electrical input is not available at t…
In the last article, we have seen the phenomenon of armature reaction in a dc generator . There are various effects in the dc generator due to armature reaction. Due to the demagnetizing effect of armature flux on the field…
In the last article, we have seen the working principle of dc generator and how we obtained the dc voltage at the output terminal. Now let us see the armature reaction of a dc generator. What is Armature Reaction ? …
When the field winding of a dc generator is excited, a flux with uniform distribution in the air-gap of the dc generator is produced. Once the generator is loaded, load current flows through the armature conductors and set …
It is seen that emf induced in the armature conductors of a dc generator is alternating in nature. The frequency of the induced emf alternates with a frequency corresponding to the product of the speed and the number of pai…
Hopkinson's test of dc machine also known as a 'Regenerative Test'. This test is also one of the efficient ways of determining the losses and efficiency of a dc machine. The test is performed by mechanical coupl…
For small ratings of dc machines, we can perform the tests directly by loading. In the case of large dc machines, it is difficult to perform tests by loading directly. For this purpose, there are indirect methods of testing…
We know that there are different types of d.c. generators based on how the field and armature terminals are connected. They are, 1. Separately excited d.c. generator. 2. Self-excited d.c. generator. a. Shunt generat…
