Department of Electrical and Electronics Engineering

EHV Power Transmission
Unit - 1
INTRODUCTION
Standard transmission voltages different configurations of EHV and UHV lines average values of line parameters power handling capacity and line loss costs oftransmission lines and equipment mechanical considerations in line performance.
Unit - 2
CALCULATION OF LINE PARAMETERS
Calculation of resistance, inductance and capacitance for multi-conductor lines calculation of sequence inductances and capacitances line parameters for differentmodes of propagation resistance and inductance of ground return, numerical exampleinvolving a typical 400/220kV line using line constant program.
Unit - 3
VOLTAGE GRADIENTS OF CONDUCTORS
Charge-potential relations for multi-conductor lines surface voltage gradient onconductors gradient factors and their use distribution of voltage gradient on subconductors of bundle - voltage gradients on conductors in the presence of ground wireson towers.
Unit - 4
CORONA EFFECTS
Power losses and audible losses: I2R loss and corona loss - audible noise generationand characteristics - limits for audible noise - Day-Night equivalent noise level- radiointerference: corona pulse generation and properties - limits for radio interference fields.
Unit - 5
ELECTROSTATIC FIELD OF EHV LINES
Effect of EHV line on heavy vehicles - calculation of electrostatic field of AC lines- effectof high field on humans, animals, and plants - measurement of electrostatic fields -electrostatic Induction in unenergised circuit of a D/C line - induced voltages in insulatedground wires - electromagnetic interference.