Locked Rotor current and Starting current of induction motor seems to be the same thing at first glance but it is not so. These are two different terms having different meaning and significance. In this post we will discuss the difference between the locked current...
Continue reading »
February 24, 2019 admin
Electrical Machines
No Comment
What is Penalty Factor? Penalty Factor in Power System is a factor (greater than unity) by which the incremental cost of power production of plant must be multiplied to accommodate for the transmission losses. It is also defined as the ratio of power generated by...
Continue reading »
December 30, 2018 admin
Power System
No Comment
PRD Spurious actuation is a case in which transformer tripping is initiated by PRD contacts even when transformer is healthy. Ideally PRD is the last line of defense and actuates when the pressure of oil increases beyond the setting value of PRD. But its spurious...
Continue reading »
December 26, 2018 admin
Power System Protection
No Comment
Harmonics in electrical system is the signal having frequency which is integral multiple of fundamental frequency. This means, if the frequency of fundamental component is 50 Hz, then the frequency of harmonics will be 2×50 (=100 Hz), 3×50 (=150 Hz) and so on. If the...
Continue reading »
December 22, 2018 admin
Power System
No Comment
Start Delta Starter is a scheme for motor starting to reduce the inrush current during starting of the motor. This method of starting is quite popular for Delta connected Squirrel Cage induction motor. In this method, the motor is first started as a star connected...
Continue reading »
December 18, 2018 admin
Electrical Machines
1 Comment
Power Angle Curve of Synchronous Machine is the graphical representation of electrical output with respect to the power angle. As we know, power angle is also known as load angle, therefore it can be said that this curve is graphical representation of electrical output of...
Continue reading »
December 16, 2018 admin
Electrical Machines
No Comment
Load Angle in synchronous machine is defined as the angle between the filed mmf or flux and the resultant air gap mmf or flux. Load angle and power angle are same thing which are used synonymously. There are basically three different types of flux in...
Continue reading »
December 14, 2018 admin
Electrical Machines
6 Comments
Equation of power flow through an inductive load provides the relationship between the sending end voltage, receiving end voltage, line parameters viz. inductance and resistance of line and the impedance angle. The equation is general and can be well applied for Synchronous generator,Synchronous Motor and...
Continue reading »
December 8, 2018 admin
Electrical Machines
No Comment
If you ever have seen the setting of Differential Protection of Transformer, you might have noticed two settings shown as Is-HS1 (called High Set 1) and Is-HS2 (called High Set 2). In this post I will be discussing about the significance of these two parameters...
Continue reading »
November 10, 2018 admin
Power System Protection
3 Comments
CT Matching Factor is basically a multiplication factor by which secondary current of CTs on HV side and LV side is multiplied to make it equal to rated secondary current. This means, if the rated CT secondary current is 1A, then multiplication of CT secondary...
Continue reading »
November 5, 2018 admin
Power System Protection
10 Comments
