Review of Research on Hydrostatic Transmission Systems and Control Strategies

In response to the issues of low energy recovery efficiency, single- and low-capacity energy storage methods, and insufficiently diverse control strategies in hydrostatic transmission systems, this paper analyzes hydrostatic systems from the perspectives of hydraulic principles and control strategies. Hydrostatic transmission systems are divided into three types: pump-controlled hydraulic systems, secondary regulation hydraulic systems, and adaptive regulation systems. The design concepts and working principles of hydraulic systems are discussed, and the control strategies for hydrostatic transmission systems are categorized into torque control, fuzzy control, and optimal control strategies. Operating conditions are analyzed, and the advantages and disadvantages of traditional control strategies are compared. The results show that utilizing techniques such as adaptive regulation to reduce the loss of energy in the transfer process and in the transformation of secondary components, as well as combining a variety of methods for integrated control, can effectively improve the efficiency of these systems. The development direction of hydrostatic transmission systems is also discussed, including further development into oil–hydraulic hybrid systems, utilization of artificial intelligence technology and network technology, optimized design concepts, and the intelligence of hydrostatic transmission systems.