The Optimal Design of an Electrohydraulic Control System Using Hybrid Computation

The development of an automotive brake test stand has required the design of a highly responsive hydraulic system in order to provide acceptable dynamic control of brake line pressure. This paper describes the analysis, simulation, and performance optimization of the electrohydraulic pressure control system built for this application. A hybrid simulation employing a patterned search algorithm was used to determine the compensation network yielding the optimum system response to a step input. Solution time comparisons between hybrid, digital, and analog simulation methods are made, and the relative advantages of each are noted. Finally, a comparison between the simulation and some experimental results indicates the validity of the analytical procedures employed.