One of the trend lines while perfection of the electromechanical and electro-technologies for the mining, oil and gas extraction industries is the development and utilization of the efficient frequency drive control systems consisting of the asynchron electrical machines. The models of drives with vector and scalar control are given for the comparable investigation of efficiency dynamic and of the asynchrony machine's power factor under frequency-regulation. The results of the transient modelling for the drives with 4A280S6 motors are presented, obtained using MatLab.
The possibilities of controlling different current coordinates of variable current machines presented by vector control systems can be used to control the main energy characteristics of the drive, such as power factor and efficiency.
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. ...
Main ventilation fan installations at mining enterprises represent the most energy-intensive consumers. Significant energy wastage and low efficiency of ventilation systems are attributed to substantial deviations between actual ventilation regimes and design parameters. This occurs because main ventilation fans are selected for the entire operational lifespan of the enterprise based on ultimate maximum design values of gas emission, explosive quantity, production volume, workforce numbers, etc. Consequently, the determination of fan operating modes for mine ventilation networks often proves insufficiently precise. ...