Energy efficient throttling control of a multi-pressure system using a genetic algorithm and model predictive control

The energy efficiency of hydraulic cylinder drives can be increased by replacing the actuator with a multi-chamber cylinder, utilising multiple supply lines with unique pressures or a combination of the concepts. Previous studies have demonstrated significant energy savings using a cascaded control system, which requires velocity feedback to stabilise the system. To avoid the need of position or velocity sensors in harsh conditions of mobile machines, this article presents a throttling control scheme, which achieves good energy efficiency on multi-pressure systems without velocity feedback. A simulation study was performed to determine the efficiency of the system, robustness against load variations and the effect of valve response time on performance.