Electric drives of escalators of subways are in the same row with the rolling stock by their purpose.
Power thyristor inverter control unit BUI must provide control of the frequency and phase of the output voltage of the autonomous inverter thyristor frequency converter THR using two input three-phase voltage systems. For this purpose, at the output of the unit, must be formed long pulses of control of the inverter thyristors, necessary for a stable and reliable start of the drive ...
When employing thyristor frequency converters (TFCs) in block control systems of AC variable frequency drives, the converter is controlled by a two-phase AC signal modulated in magnitude, frequency, and phase. …
Based on the principle of output voltage formation, direct frequency converters are divided into two main types: thyristor-based direct frequency converters with natural commutation (DFC-NC) and thyristor-based direct frequency converters with forced commutation (DFC-FC). In DFC-NC, the output frequency is formed through natural commutation within a half-cycle of the output voltage. ...
For the analysis of the spectral composition of the output voltage in the previously proposed thyristor-based direct frequency converter with forced commutation (DFC-FC), we shall employ the following expression…
The increase in labour productivity in mines and the improvement of miners' working conditions have led to the widespread implementation of mining complexes with coal-cutting machines. To ensure high operational efficiency under various conditions, coal-cutting machines must incorporate regulation of both feed and cutting speeds. ...