Electrical Power Systems Technology

150 Electrical Power Systems Technology Voltages are developed in each stator winding as the electromagnetic field rotates withi ...

Alternating Current Power Systems 151 beginning of one phase winding is connected to the end of the adjacent phase winding. Thus ...

152 Electrical Power Systems Technology phase transmission line, and three-phase power is more economical than single-phase powe ...

Alternating Current Power Systems 153 GENERATOR FREQUENCY The frequency of the sinusoidal waveforms (sine waves) produced by an ...

154 Electrical Power Systems Technology Sample Problem: Given: a power line frequency of 60 hertz is applied to an electric moto ...

Alternating Current Power Systems 155 VNL – VFL VR = ————— × 100 VFL 122.5 – 120 × 100 = ———————— × 100 120 VR = 0.02 = 2% GENER ...

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157 Chapter 7 Direct Current Power Systems Alternating Current (AC) is used in greater quantities than direct current (DC); howe ...

158 Electrical Power Systems Technology Specific Gravity Ampere-Hour Rating Nickel-Iron (Edison) Cell Nickel-Cadmium Cell Silver ...

Direct Current Power Systems 159 time. After this period of time its chemicals can no longer produce elec- trical energy. Second ...

160 Electrical Power Systems Technology Figure 7-1. Batteries—Common sources of direct current (DC): Cutaway of a general purpos ...

Direct Current Power Systems 161 V I = ————— Ri + RL where: I = the current in amperes, V = the voltage or electromotive force ( ...

162 Electrical Power Systems Technology Vo = V – IRi where: Vo = the output voltage of the cell in volts, V = the no-load cell v ...

Direct Current Power Systems 163 Applications of Primary Cells There are many types of primary cells available today, with unlim ...

164 Electrical Power Systems Technology is the nuclear cell. Such cells convert the energy given off by atomic nu- clei into ele ...

Direct Current Power Systems 165 clear cell shown in Figure 7-6 has air removed through the center tube to form the vacuum insid ...

166 Electrical Power Systems Technology rent to a load connected to it, the chemical process can be expressed as: PbO 2 + Pb + 2 ...

Direct Current Power Systems 167 charge and the operating temperature of the battery. The normal operat- ing temperature is cons ...

168 Electrical Power Systems Technology cate the state of charge of the nickel-iron cell. This cell is also charged by applying ...

Direct Current Power Systems 169 Construction of DC Generators The parts of a simple DC generator are shown in Figure 7-9. prin- ...