Home / Electric Power

Electric Power

It covers articles related to single and three phase power.

Power Quality Problems in Power Distribution System

Correcting power quality problems requires an understanding of all power distribution system components and how a problem in one component can cause problems in other components. Distribution system components include transformers, distribution lines, switchboards, and panel boards, disconnects, circuit breakers, fuses, and receptacles to deliver, control, and protect the system. …

Read More »

What is a Smart Grid | Components

What is a Smart Grid | Components

An electrical grid is a network that delivers electrical power from the power plants where it is generated to customers. See Figure 1. An electrical grid includes wires, substations, transformers, and switches. Definition: A smart grid is an electrical grid that uses computer-based remote control and automation to deliver electrical …

Read More »

Electrical Elementary Diagrams

Electrical Elementary Diagrams

When the circuit components are either large, remote from each other, or numerous in a given electrical-power distribution system or control process drawing, the pictorial wiring diagram is an ineffective way to relay the required information. A different type of drawing, called the elementary diagram, which displays only the electrical …

Read More »

Circuit Breaker Types and Their Uses

types-of-circuit-breakers

Low-voltage circuit breakers are typically used in applications such as lighting circuits, motor control centers, feeder circuits and any application in which electrical power needs to be turned on and off and overcurrent protection is required. Medium-voltage circuit breakers are used in many of the same types of applications as …

Read More »

Medium Voltage Circuit Breakers Operation

medium voltage circuit breaker

Low- and medium-voltage Vacuum circuit breakers are similar in construction and operation. One of the primary differences between them is that the OCPDs on LVPCBs are mounted on the circuit breakers, while medium-voltage circuit breakers use protective relays, which are typically mounted on the enclosure door. Medium-voltage circuit breakers have …

Read More »

Circuit Breaker Schematic Diagram

Schematic-diagram-of-a-circuit-breaker-

A schematic diagram is a drawing that shows electrical system circuitry with symbols that depict electrical devices and lines representing conductors. Only qualified persons should review schematic diagrams and perform work on circuit breakers. A qualified person is a person who has special knowledge, training, and experience in the installation, …

Read More »

Phase Sequence in Three-Phase System

Phase Sequence in Three-Phase System

In a three-phase service supplied by an electrical utility company, all three line voltages have the same magnitude and are displaced from one another by 120°. We can measure the magnitude of these voltages quite readily. However, the magnitudes do not tell us whether VBN leads VAN by 120° or …

Read More »

Advantages of Polyphase System

Advantages of Polyphase System

The two-phase alternator in Figure 1(a) has two identical loops mounted on the same rotor. Since both loops have the same number of turns and rotate at the same angular velocity, the voltages induced in them have the same magnitude and frequency. Loop A is mounted on the rotor 90° …

Read More »

Power Triangle and Power Factor in AC Circuits

Power Factor Correction using Capacitor

Power Triangle The real power in the circuit of Figure 1 can be found from the product of VR and I, and the reactive power from the product of VL and I. Since VL leads VR by 90°, \[\begin{matrix}{{V}_{T}}=\sqrt{V_{R}^{2}+V_{L}^{2}} & {} & \left( 1 \right) \\\end{matrix}\] Figure 1 AC circuit …

Read More »

AC AC Power Converter

AC AC Power Converter

For AC-to-AC conversion the voltage and/or the frequency are the parameters that might need to be increased or decreased. For voltage only, a transformer can be used. But, for the frequency change, and for both frequency and voltage change, use of electronic converters becomes necessary. Unidirectional Back-to-Back Converters The key …

Read More »

Transmission Line Effects

Transmission Lines Effects

This section briefly describes matters concerned with transmission lines in electrical networks. Knowledge of the material described here is very useful for the technical personnel in electricity and its generation and distribution. Inductive and Capacitive Effect In addition to the ohmic resistance in the wires and electric conductors, conductors carrying …

Read More »