Indepth Electrical engineering

In small DC machines the coils are directly wound in the armature slots. In large DC machines, the coils are performed and then inserted into the armature slots. Each coil consists of a number of turns of wire, each turn taped and insulated from the other turns and form the rotor slots. Each side of the turn is called the conductor. The number of the conductors on a machine's armature is given by                                       Z= 2CN where : Z= numbers of conductors on rotor C= numbers of coils on rotor N= number of turns per coil There are two types of armature windings in DC motors :- 1.   Lap winding 2.   Wave winding. In this article we will discuss about Lap winding:- Lap Winding:- In this winding continuous coils overlap each other. In this wi...

V/f Control of Induction Motors – Working, Characteristics, and Applications Introduction V/f control, also known as Volts-per-Hertz (V/Hz) control , is the simplest and most widely used method of controlling the speed of induction motors. It is especially popular where precise tuning is not required and motors need to operate up to 1000 Hz . This method is widely adopted in industrial applications because it allows multiple motors to be started on a single VFD (Variable Frequency Drive) , which is not possible with encoder-based vector control systems. Principle of V/f Control The principle of V/f control is simple: To maintain constant flux in the motor , the ratio of applied voltage to supply frequency (V/f) must remain constant. At lower frequencies, the voltage is reduced to avoid magnetic saturation, while at higher frequencies, the voltage is increased proportionally. This ensures the motor operates efficiently across a wide ra...

As we know that Ohm’s law can be applied to circuits where there are resistive circuits only.  Now in electrical systems there are so many complex circuits consisting of lot of other load other than resistive loads. There are some circuits such as Bridge circuits which can’t be solved by using ohm’s law to find out voltages and currents circulating in the circuit. Kirchoff’s current law is used to solve the circuits to find out the current flowing the respective branches. Kirchoff’s current law was given by Gustav Kirchoff in 1845. There are two laws given by Kirchoff naming as Kirchoff’s current law and Kirchoff’s voltage laws. KCL deals with current flowing in a closed circuit whereas KVL deals with voltage sources present in a closed circuit. Kirchoff’s Current Law:- According to this law “Total current entering a Junction or node is equal to current leaving the same junction or node”.  This means that algebraic sum of currents entering and leaving the junction ...

Star to Delta and Delta to Star conversions 1. Star (Y) to Delta (Δ) Conversion Formula Chart Diagram of Star connection with resistances R1, R2, R3. Diagram of Delta connection with resistances RA, RB, RC. Side-by-side formulas: R A = R 1 R 2 + R 2 R 3 + R 3 R 1 R 3 RA = \frac{R1R2 + R2R3 + R3R1}{R3} R B = R 1 R 2 + R 2 R 3 + R 3 R 1 R 2 RB = \frac{R1R2 + R2R3 + R3R1}{R2} R C = R 1 R 2 + R 2 R 3 + R 3 R 1 R 1 RC = \frac{R1R2 + R2R3 + R3R1}{R1} 👉 Visual cue: “Opposite branch rule” (product of two + sum of all / opposite resistor). 2. Delta (Δ) to Star (Y) Conversion Formula Chart Diagram of Delta with RA, RB, RC. Diagram of Star with R1, R2, R3. Formulas neatly highlighted: R 1 = R A ⋅ R B R A + R B + R C R1 = \frac{RA \cdot RB}{RA + RB + RC} R 2 = R A ⋅ R C R A + R B + R C R2 = \frac{RA \cdot RC}{RA + RB + RC} R 3 = R B ⋅ R C R A + R B + R C R3 = \frac{RB \cdot RC}{RA + RB + RC} 👉 Visual cue: “Node rule” (product of two connected / sum of all)....

Losses in Transformers: Core Losses & Copper Losses Explained Transformers are the backbone of electrical power systems , used for stepping up and stepping down voltages in transmission and distribution. Like all electrical devices, they are not 100% efficient. Some part of input power is lost in the form of heat, called transformer losses . Since transformers are static devices (no moving parts), they don’t have mechanical losses like motors or generators. Instead, they primarily suffer from electrical losses , which can only be minimized, not eliminated. The two main types of transformer losses are: Core Losses (Iron Losses) Copper Losses (Ohmic Losses) 1. Core Losses (Iron Losses) Core losses occur in the magnetic core of the transformer. These losses are independent of load current and remain constant, hence also called No-Load Losses . Core losses consist of: Hysteresis Losses Eddy Current Losses (a) Hysteresis Losses The transformer core is made...