Electromechanical energy conversion is one device which is convert energy one form to another form. electromechanical device converts electrical energy into mechanical energy and vice versa. Energy conversation take place through the medium of electric field or magnetic field.Electromechanical energy conversion devices with magnetic field as the coupling medium between electrical and mechanical systems are more common in commercial application. the energy storing capacity of the magnetic field is much greater about 25,000 greater than the electric field.
electromechanical energy conversion is a reversible process except for the losses in the system. Here we use word reversible that means the energy can be transfer back and forward between mechanical and electrical system. during the process of energy conversion, some of the energy is converted into heat and it lost from the system.

Electromechanical energy conversion devices may categorized in Various parts as under:-

1.      The first category of devices, involving small motion, processes only low-energy signals from electrical to mechanical or vice versa. These are microphones, gramophone pick-ups, loud speakers and low-signal transducers.

2.      The second category consists of force or torque-producing devices with limited mechanical motion. These are electromagnets , relays, moving-iron instruments etc..

3.      The third category includes continuous energy conversion devices like motors and generators these are used for bulk energy conversion and utilization.

Principal of energy conversion:-

Its state that the energy cannot be created or destroyed. it can only be converted from one form to the another form of energy.
If we consider electric Generator then its convert mechanical energy into electrical energy
If we consider electric Motor then its convert electrical energy into mechanical energy.

Electromechanical energy conversion system has basically divided in three parts,

1.      Mechanical system

2.      Field coupling system

3.      Electrical system

Principal of energy conversion is based on below equations.

Energy transfer equation for generator action can be written as,
Mechanical energy input = electrical energy output  + losses in field + total energy losses

Energy transfer equation for motoring action can be written as,
Electrical energy input = mechanical energy output + stored energy by filed + total energy losses

During the energy conversation there are occur some Losses, which are following as,

·         Core losses or iron losses

·         Electrical losses or copper losses

·         Mechanical losses
This all losses are called energy losses,
Energy losses equation can be written as,

Electrical energy input – copper loss = (mechanical energy output + mechanical losses) + ( core losses + energy stored in core)

Wie – Wle  = ( Wom + Wlm ) + ( Wfd + Wlf )
Where, Wie = input electrical energy
Wle=copper losse
Wom = output mechanical energy
Wlm = mechanical losses
Wfd = stored energy by core
Wlf = core losses.