High Voltage Engineering

Introduction: Generation and transmission of electric energy. Voltage stresses. Testing voltages. Generation of High Voltages: Direct voltages. Alternating voltages. Impulse voltages. Measurement of High Voltages: Peak voltage measurement by spark gaps. Electrostatic voltmeters. Ammeter in series with high impedance and high ohmic resistor voltage dividers. Generating voltmeters. The measurement of peak voltages. Voltage dividing systems and impulse voltage measurements. Electrostatic Fields and Field Stress Control: Electrical field distribution and breakdown strength of insulating materials. Fields in homogeneous, isotropic materials. Fields in multi-dielectric, isotropic materials. Experimental field analysis techniques. Numerical methods. Electrical Breakdown in Gases, Solids and Liquids: Classical gas laws. Ionization and decay processes. Cathode processes - secondary effects. Transition from self-sustained discharges to breakdown. The streamer or 'kanal' mechanism of spark. The sparking voltage - Paschen's Law. Penning effect. The breakdown field strength (Eb). Breakdown in non-uniform fields. Effect of electron attachment on the breakdown criteria. Partial breakdown, corona discharges. Polarity effect - influence of space charge. Surge breakdown voltage - time lag. Breakdown in solid and liquid dielectrics. Non-Destructive Insulation Test Techniques: High voltage dielectric loss and capacitance measurements. Partial-discharge measurements. Overvoltages and Insulation Coordination: The lightning mechanism. Simulation lightning surges for testing. Switching surge test voltage characteristics. Insulation coordination. References. Index.321 lit. refs., 240 illus.