Braking and 4 Quadrants Operation: Subsynchronous converter cascades have been used, till now, in applications requiring one quadrant operation. These can be employed for drives where at least one electrical…
Speed Control Using Slip Energy Recovery Schemes: The foregoing discussion makes it very clear that the methods of voltage control and rotor resistance control have poor efficiency, particularly at low…
3 Phase Induction Motor Construction: A converter fed 3 Phase Induction Motor Construction has the following advantages over a line fed motor: 1.Smooth start up is guaranteed by variable frequency…
DC Chopper: DC Chopper are mainly dc to dc single stage conversion devices which provide a variable voltage on the load side when fed from a constant dc voltage source.…
Polarised Relay: This Polarised Relay is very frequently employed where operation is required in two directions. In a d.c. Polarised Relay contact A is closed when current in the operating…
Level Detector: Schmitt trigger or level detector circuits are very often employed in static relay circuits as a final stage before the trip coil circuit of the circuit breaker. The…
Characteristics of Protective Relay: Characteristics of Protective Relay elements using different operating principles. These principles and design criteria determine how well the basic function is performed and how in practice…
Types of Protective Relays: Basically, Types of Protective Relays are analogue-binary signal converters with measuring functions. The variables such as current, voltage, phase angle or frequency and derived values obtained…