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…
Basic Ideas of Protection Relay: Basic Ideas of Protection Relay should ensure the availability of electrical energy without interruption to every load connected to the system. When the electric power…