Compact gensets and industrial gensets are often operated in S/W mode only. For certain tasks, however, the power packs can also be implemented with variable speed. An example of a hydraulic power pack with proportional control of a DC motor is shown below.
Example of variable speed drive
Various DC motors are possible in principle. Shunt or series motors as well as permanent magnet DC motors (PMDC motors). In this example, a PMDC motor is used. This is characterized by the fact that the field is generated by a permanent magnet. The commutation of this motor is implemented with the help of carbon brushes.
An 800 Watt motor is used.
The motor control for the aggregate is realized in this case by a half bridge. A reversal of the direction of rotation is not possible with this. This function is generated hydraulically via a 4/3-way valve. T1 PWM is controlled for proportional control.