|Instytut Automatyki Politechniki Łódzkiej||Łódź, 22-24 listopada 2017
kosene @ info.p.lodz.pl
Plenary lecture „Energy Efficiency for High-Power Electrical Drives” will be given by professor Joachim Holtz
Methods for increasing the power rating and the efficiency of high-power drives are subject of the Keynote Address. The current rating of medium voltage semiconductor devices determines the motor currents, while the motor voltages are stepwise increased as the power level in increased. Connecting power devices in series creates losses in associated circuits for dynamic voltage balancing. Loss-less balancing of a pair of series connected devices is enabled by the three-level inverter topology. A side effect is reducing the harmonic current distortion which reduces resistive motor losses. The voltages are further increased by series connection per the 6respective phases of three-level inverter legs. Output power of several hundred megawatts is thus achieved. Carrier modulation requires switching frequencies around 1 kHz. Optimal modulation techniques permit operating below 200 Hz without increasing current distortion. The device switching losses are thus reduced. It increases the power rating of a given inverter by about 250% and the efficiency is 99% in 28-MW drive.
|Strona zaktualizowana: 23.03.2015|