kollektorloser d.c., treiberschaltung for a kollektorlosen d.c. motor and process for operating a kollektorlosen gleichstrommotors.

摘要

The motor has a permanent magnet rotor with at least two poles and at least one stator winding supplied from a constant voltage supply with pulses from a control circuit which is responsive to a sensor in the airstream provided by the fan. The control circuit has semiconductor elements which operate as switching elements for part of the control cycle and as analogue amplifying elements for another part of the control cycle. In the region of max. speed, the speed is varied by the direction of switching the motor current in the commutating mode, and at lower speeds, speed is varied by controlling the amplitude of current supplied to the stator windings. A temp.-independent sensor responsive to motor current protects the motor against overloads which persist for more than a predetermined time. A comparator compares the actual speed with the required speed and triggers an alarm if the speed deviation is excessive.