Contents
What is DC motor and DC generator?
DC motor converts electrical energy into mechanical energy whereas DC generator converts mechanical energy into an electrical energy.
What is the advantage of motor generator set Mcq?
Low maintenance cost: The equipment can be maintained by electricians and/or mechanics; no specialist is required. Also, on horizontal, single-shaft MG sets, there is no coupling, gear nor belt to wear out. Exciters are brushless; there are no commutators or brushes to replace.
What is the working principle of DC generator?
A DC generator operates on the principle of Faraday’s laws of electromagnetic induction. According to Faraday’s law, whenever a conductor is placed in a fluctuating magnetic field (or when a conductor is moved in a magnetic field) an EMF is induced in the conductor.
What is the use of motor generator?
Motor generators are used to isolate electrical loads from power supply lines. It consists of an electrical generator driven by an electric motor. This is used to convert the electrical power frequency, voltage, and phase.
Can a brushless DC motor be used as a generator?
Rule #1: For generation of DC voltage select a brushed DC motor or use a brushless EC (BLDC) motor with voltage rectifier. For the generation of AC voltage, select a brushless EC motor and connect 2 phases only. Hall sensors are not needed on brushless motors. Many generators are operated at speeds of 1000 rpm or below.
Why does a generator need a high resistance motor?
Rule #2 requires motors with high generator constant. Unfortunately, these windings have the highest resistance as well. High resistance reduces the output voltage under load and the output voltage becomes very sensitive to the load current.
What should the speed constant of a generator be?
Table 1 shows a selection of motors with low speed constant (or high generator constant = generated voltage per speed). Usually, it’s the motor winding with the highest resistance only that results in a speed constant of less than 100 rpm/V. Rule #2: Without considering the load, the winding should have a speed constant of kn < n/u or smaller.
Can a DC alternator be used as a generator?
If the motor has a separate field winding instead of a permanent magnet, you will need to energise that winding from an external DC source, e.g. a battery. For example, a car alternator has DC slip-rings (not a commutator!) to supply a small field current to the rotor, and a three phase (usually) stator winding.