Phase Synchronizing Device or Controlled Switching Device

When we switch off an online circuit breaker to cut an inductive load, it is ideally desired to interrupt the current of the system during its zero crossing of the current waveform. But practically it is somewhat impossible to maintain the condition. In normal circuit breaker the current interruption may occur at an instant near … Read more

Types of Electrical Reactor

Reactor has many roles to play in electrical power system. The reactors are normally classified according to their modes of applications. Such as, Shunt Reactor Current Limiting and Neutral Earthing Reactor Damping Reactor Tuning Reactor Earthing Transformer Arc Suppression Reactor Smoothing Reactor etc. From constructional point of view the reactors re classified as Air Core … Read more

Selection of Reactor for Different Applications

There are different types of reactors available according to their design and constructional features. Each type of reactors has its own unique application. Air Core or Coreless Reactor without Magnetic Shield This type of reactor is constructed by wrapping insulated copper or aluminum conductor of suitable cross section on a ceramic, concrete, fiber glass or … Read more

Construction of a Shunt Reactor

Shunt Reactor is used to compensate capacitive reactive power of a long transmission line. The constructional features of a shunt reactor may vary manufacturer to manufacturer but basic of construction is more or less same. Core of Shunt Reactor Gapped Core is generally used in shunt reactor. The core is constructed from Cold Rolled Grain … Read more

Tests of Shunt Reactor

As per IS 5553 the tests performed on an EHV or UHV shunt reactor can be categorized in three different groups. Type tests Routine tests Special tests. Type Tests of Shunt Reactor The following tests are essentially performed on a shunt reactor as type tests Measurement of Winding Resistance. Measurement of Insulation Resistance. Measurement of … Read more

Measurement of Reactance of a Shunt Reactor

The following two factors to be considered during measurement of reactance of a shunt reactor. The reactance of a shunt reactor is approximately equal to its impedance as the resistive component of the impedance in shunt reactor is negligible. The V-I characteristics of the shunt reactor is almost linear under operating range of applied voltage. … Read more

Winding Resistance Test of Shunt Reactor

Winding resistance measurement of reactor or any other similar electrical equipment determines the following information. Calculation of copper losses. Calculation of winding temperature at the end of the winding temperature rise test cycle. Indication of any damage occurs in the winding system. Principle of Winding Resistance Measurement Previously, winding resistance was measured by Kelvin Bridge … Read more

Arc Suppression Coil or Petersen Coil

There is always a significant charging current flowing from conductor to earth in underground high voltage and medium voltage power network. This is because of dielectric insulation between earth and conductor in the underground cables. During an earth fault in any phase, in a 3 phase such system, the charging current of the system ideally … Read more

Three Phase Shunt Reactor

Three phase shunt reactor is generally connected to 400KV or above electrical bus system for capacitive reactive power compensation of the power system and to control dynamic over voltage occurring in the system due to load rejection. The shunt reactor should be capable of withstanding maximum continuous operating voltage (5% higher the rated voltage in … Read more

Measurement of Losses in Shunt Reactor

We should measure the losses of a shunt reactor at rated voltage and frequency. But for very high voltage shunt reactor, it may be difficult to arrange such a high test voltage during measurement of losses. This difficulty can be overcome, by measuring the losses of the shunt reactor at any voltage lower than the … Read more