UNIT 1 INTRODUCTION: With increase in population the need for electricity also increases therefore it is necessary to rise number of electrical engineers. The electrical engineering mainly deals with generation , transmission and distribution of electricity. Electrical circuits is the basic and fundamental subject which lays path to understand subjects related to generation , transmission and distribution of electricity. In the first unit we shall deal with what is electrical circuit and formation of electrical circuit. Knowing or unknowing we come across electron in our life daily, studying the properties of these electrons leads to the terms voltage, current and power. Hence the basic definitions of voltage , current , power and energy are studied here. Basic Parameters: Here we shall deal with three basic parameters so called RESISTOR, INDUCTOR AND CAPACITOR with out which formation of electrical circuit is highly difficult. What are these element? , the properties, beahviour, relation between voltage and current in these elements are studied . later formation of electrical circuit and network using these elements is studied. Formation of electrical circuits using these elements depends mainly on the nature of supply. For DC source networks one can use only resistors and for AC source networks one can combinations of RLC elements. Inductor and capacitor are also called as energy storing elements. Later we shall see classification of elements from the knowledge of this one can able to identify the element required to form that particular circuit.
Formation Of Electrical Circuit Or Network: There are several combinations of we can use to form electrical network using RLC, they are only R, R-L, R-C, L-C, R-L-C and these arrangements can be done in different types like series, parallel, series-parallel and parallel –series connections. Source: To lead the network we need source , where source is defined as an active element which delivers power. Mainly there are two types of source– voltage and current source, but practically voltage source exist, again these sources are classified as DC and AC source. General sources are called as independent sources and their exist depend sources also which dummy one. Basic Laws: The statements of ohm’s law, kirchoff’s laws are seen here. With the knowledge these laws one can be able to study the behavior of network, type of source required depending on connection of elements. Network Reduction Techniques: These reduction techniques are used to reduce any complex network into simple one and then simplify for required result. These are used to determine equivalent resistance, source current, current through each element, voltage across each element and total power deliver and total power received by the elements. Some of techniques are named as mesh analysis, nodal analysis, source transformation and star-delta transformation.
Conclusion: By the end of this unit one can understand the basic parameters to form electrical network, formation of electrical network, simplifying the network using different reduction techniques to determine voltage, current and power in the network.
UNIT 2 INTRODUCTION: In general transmission of Dc power is difficult and not economical and even Dc generation is also less , hence more units are required to meet demand to overcome above drawbacks the AC generation came into existence , therefore before going to study in depth about Ac generation, transmission and distribution it is necessary to have the knowledge of alternating quantities and their importance in power systems. Alternating Quantity: In the definition alternating quantity is one whose value changes from time to time , if this change periodically happens then it is called as periodic alternating quantity otherwise nonperiodic alternating quantity. There are many periodic functions but best one sinusoidal function. Hence generally sine function is used to represent periodic waveform because of following reasons, It can be easily generated. Integration and differentiation of sine function is again sine function only. Hence we shall study what is sine function?, representation of sine function, definitions related sine functions and its applicability in power system networks. Some of the definitions related to sine wave are peak value, peak to peak value, average value, RMS value, peak factor and form factor. AC Circuit: An AC circuit consists of an source, RLC elements and connecting wire, here AC source could be an alternating voltage source or alternating current source. Before formation of AC circuit one should have the knowledge of reactance, impedance, susceptance and admittance offered by R-L-C parameters. In the definitions :