Controlled Switching Devices in the Medium Voltage RangeOver three decades ago, Controlled Switching Devices (CSDs) were first introduced to mitigate switching transients caused by high voltage circuit breakers connected to shunt reactors and capacitor banks. Subsequent research expanded their application to transmission lines and power transformers. Initially, these devices optimized switching moments on a per-phase basis using independently pole-operated circuit breakers (IPO).Recently, the su

Power System Frequency DefinitionPower system frequency is the rate of change of the phase angle of AC voltage or current, measured in hertz (Hz).Historical InfluenceThe choice of 50 Hz in India and 60 Hz in other regions is based on historical and economic factors, not technical reasons.Advantages of 60 HzA 60 Hz system has more power output and allows for smaller electrical devices but may need more cooling.Advantages of 50 HzA 50 Hz system can support longer transmission distances with lower

Transistor DefinitionA transistor is a semiconductor device used to amplify or switch electronic signals and electrical power.Diffused TechniqueThis method creates planar transistors on a nearly flat wafer. An N-type wafer is heated in a furnace with P-type gas impurities, causing the P-type region (base) to form on the wafer. A mask with holes is used, and the wafer is heated again with N-type impurities. This creates the N-type region (emitter) on top of the P-type layer.At last, a thin layer

What is Diode Current Equation?Diode Current Equation DefinitionThe diode current equation expresses the relationship between the current flowing through the diode as a function of the voltage applied across it. Mathematically the diode current equation can be expressed as: I is the current flowing through the diodeI0 is the dark saturation current,q is the charge on the electron,V is the voltage applied across the diode,η is the (exponential) ideality factor.is the Boltzmann constantT is the ab

What is a Square Wave Inverter?Square wave inverter definitionSquare wave inverter is an electronic device that converts direct current into alternating current, and its output alternating current waveform is in the form of square wave.Working principleThe working principle of the square wave inverter is based on simple switching technology. It uses electronic switches (such as relays or transistors) to periodically turn on and off DC power, resulting in alternating currents. Since the waveform

What is Variable Frequency Drive?Variable Frequency Drive DefinitionA variable frequency drive is a device that regulates the speed and torque of an AC motor by altering the frequency and voltage of its power supply.Core ComponentsA VFD consists of a rectifier to convert AC power to DC, a capacitor to stabilize this DC power, and an inverter to convert the DC back to AC with variable frequency.Operational MechanismA variable frequency drive works by changing the frequency and voltage of the powe

What is the EMF Equation of DC Generator?EMF definitionElectromotive force (EMF) in a DC generator is defined as the voltage generated by the movement of a conductor through a magnetic field.Faraday's lawThis law explains that the induced electromotive force in a generator conductor is proportional to the rate at which it crosses the magnetic field line.Generator groupA DC generator consists of a conductor, a magnetic field, an armature, a magnetic pole, and a winding path, which together affect

Torque equation definitionThe torque in the three-phase induction motor is calculated based on rotor current, magnetic flux and power factor.Rotor currentThe rotor current is critical for generating torque and is affected by the induced electromotive force and impedance of the rotor.Starting torqueStarting torque is the torque generated when the induction motor is started. We know that at the beginning of the rotor speed, N is zero.Therefore, just by placing the value of s=1 in the torque equati

What is a Squirrel Cage Induction Motor ?Squirrel-cage induction motor definitionA squirrel cage induction motor is a motor with a rotor that looks like a squirrel cage and operates based on electromagnetism. The rotor is a steel-laminated cylindrical assembly containing a highly conductive metal such as aluminum or copper. When alternating current flows through the stator windings, it creates a rotating magnetic field. The process induces an electric current in the rotor, which creates its own

What are the Torque Slip Characteristics of Induction Motor?Torque Slip Characteristics DefinitionThe torque slip characteristics of an induction motor describe how its torque changes with slip.SlipSlip is the difference between synchronous speed and actual rotor speed, divided by synchronous speed.The torque-slip characteristic curve can be divided roughly into three regions: Low slip region Medium slip region High slip regionMotoring ModeIn motoring mode, the motor runs below synchronous speed