Category: Power System Articles

Two-watt meter method is used for measuring power in 3 phase 3 – wire star or delta connected systems either with the balanced or unbalanced load. Let us discuss the two wattmeter method for 3 phase power measurement with star and delta connection in detail. Measurement of power by the two wattmeter method in star connection: In this method, we use two-watt meters and the current coils of these watt meters are connected in series with two lines and potential coils are connected across these two lines and the load is…

What Is Electrical Power Factor? The cosine of the angle between voltage and current in an a.c. the circuit is known as power factor. In an a.c. circuit, there is generally a phase difference φ between voltage and current. The term cos φ is called the power factor of the circuit. If the circuit is inductive, the current lags behind the voltage and the power factor are referred to as lagging. However, in a capacitive circuit, current leads the voltage and power factor is said to be leading. Consider an inductive…

Sag & Tension  in transmission line Today we are going to learn a topic called sag and tension in the transmission lines.During the erection of overhead transmission line, the conductors are connected between two tower structures. The conductors connected between the tower structures must not be connected too tight or too loose. If they are connected very tightly, the tension on the conductor will be very high and at some point, it may break. If they are connected very loose, the charging current increases the length of wire to be used and the height of the tower structure…

Star – Delta Starter To start a large induction motor we use star – delta starter because large induction motors(cage type) with delta connected stator when started directly online it produces large starting current surges which cause fluctuations in voltage on the supply line. To prevent this we run the induction motor at the reduced voltage at the start of the induction motor and later on after getting require speed we operate induction motor at full supply voltage for this purpose we use star the delta starter. Working Principle Of Star…

  What is a bus bar? A bus – bar is a conductor or group of conductors and it collects electric energy from incoming feeders and distributes them to outgoing feeders. So bus – bar is a junction where all incoming and outgoing currents meet. Bus – bar is generally made up of aluminum but not with copper because aluminum has special characters like higher conductivity, lower cost, excellent corrosion resistance, etc. Criteria For Choosing Type Of Bus – Bar Arrangement: We have different types of bus – bar arrangements…