Air flow regulation for mine ventilation - utilises digital comparison of required and transducer values to control shutters

摘要

Signals from transducers in a mine ventilation system are compared digitally with a demanded value of flow. The difference signal is then used to control servomotors which operate regulator shutters. An electropneumatic transducer (12) is placed in a mine ventilation system to sense speed of air flow. The transducer output is converted (8, 13) to binary code for application to a digital comparator (1) for comparison with a required value (2). An indicator (11) provides indication of the position of flow regulator shutters (5). The comparator output is compensated (6) for disturbance forces and then applied to a power amplifier (7) to drive the motor assembly (4) controlling shutter positions.