The design of hydraulic digital valves, which is the number of on/off valves, their size and dynamical characteristic, strongly influence the behavior of hydraulic systems. This issue is discussed in the master’s paper, where we used analytical and numerical methods for the characterization of the hydraulic system controlled by a hydraulic digital valve in positioning control. The first part of the paper describes the design of digital valves and their basic components which are on/off valves. The characteristics, static and dynamic properties, which are achievable with the use of different actuators of on/off valves. Furthermore the paper deals with different control methods, which simultaneously determine the structure of the hydraulic digital valve. The binary method, pulse number modulation and the combination of the both is examined in detail. The central part of the paper includes the hydraulic system controlled with a digital valve, for which we have developed a simulation model. We performed a simulation analysis of the positioning of the hydraulic cylinder by using different positioning steps and different digital valve configurations. In detail we analyzed the influence of size and responsiveness of on/off valves and the parameters of control methods on the behavior and responsiveness of the hydraulic system. In the final part of the paper we analyzed the influence of the use of single-piston and double-piston cylinders on the behavior of the hydraulic system The simulation results and main findings are written in the conclusion.
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