Tricky but Easy Electrical Engineering!
What is Sulphation? Sulphation in Lead Acid Battery refers to the formation of Lead Sulphate (PbSO4) on the plates of battery. For better understanding of Sulphation, let us first consider the chemical reaction taking place in the lead acid battery. In lead acid battery, lead dioxide (PbO2) acts as a positive plate and lead (Pb) … Read more
Unlike a PMMC instrument, the electrodynamometer type instrument has non-uniform scale. The non-uniform scale of this instrument can be explained by the equation of deflection. As we know that the deflection in electrodynamometer type ammeter and voltmeter is given as Ɵ = KI2dM/dƟ for ammeter and Ɵ = KV2dM/dƟ for voltmeter Therefore, if dM/dƟ is … Read more
What is Point on Wave Controller / Switch? Point on Wave Switch (PoW) , often called Point on Wave Controller is a high speed microprocessor based relay used for the controlled switching of circuit breaker of HVAC system. Controlled switching refers to open or close a breaker at a pre-determined point on the voltage waveform. … Read more
Excitation system in a Generator is essential for the production of working magnetic flux in the air gap. It is usually provided by having filed winding on the rotor in case of Synchronous Generator. Providing field winding on the rotor possess certain advantages over field winding on the stator (Read Why Armature Winding on Stator … Read more
Gauss Law states that, the flux of net Electric Field through a closed surface is equal to the net charge enclosed by the closed surface divided by permitivity of space. Therefore, mathematically it can be written as ∫E.ds = Qint/ξ (Integration is done over the entire surface.) where Qint = Total charge enclosed … Read more
Generator Compounding Characteristics is a curve depicting the variation of field current required to maintain a constant generator terminal voltage. Generator terminal voltage is maintained constant by controlling its field current either manually or by Automatic Voltage Regulator (AVR). Let us consider the phasor relation between the excitation voltage Ef and terminal voltage Vt for … Read more
V-curve and power factor control of generator are closely related to each other. V-curve of Generator is basically a plot of variation of armature current with the change in field current. For a constant power, V-curve can only be obtained for generator connected to infinite bus / grid. There does not exists any such curve for an isolated … Read more
Electric Power is always transmitted at the possible highest voltage level. Earlier it was transmitted at 220 kV, then after advancement of technology it raised to 400 kV. But these days in India, the highest voltage level at which electric power is transmitted is 765 kV. Well, have you ever think of why do we … Read more
When the distance between the three phase line conductors are not same i.e. they are not spaced equally from each other then it is said to have unsymmetrical spacing. Unsymmetrical spacing of overhead line conductors give rise to unequal voltage in the individual phases at the receiving end even though the flow of current in … Read more
What is Critical Disruptive Voltage? Critical Disruptive Voltage is defined as the minimum phase to neutral voltage required for the Corona discharge to start. Basically corona discharge is the current discharge in the air. Therefore it is quite obvious that surrounding air shall breakdown for corona to start. From the basic of Electrostatics, we can … Read more