Today, the hydraulic or fluid power systems on a car, such as brakes and power steering, are strictly using fluid power. In the future, these systems may become totally electric, without any hydraulic or fluid power. Until then, the industry is using a combination of electronics and hydraulics, thus the name electrohydraulic. Through decades of research and experience, BOSCH has developed comprehensive knowledge in the field of electrohydraulics. Electrohydraulic Proportional and Control Systems conveys the state-of-the-art in electrohydraulics by presenting modern proportional control valves and servo solenoid valves, as well as open-loop and closed-loop control concepts. The operating principles of hydraulic and electronic components are described clearly and systematically in this book.Contents include: Proportional Control Valves Servo Solenoid Valves Servovalves Servo Cylinders Measurement Systems Proportional Technology Applications in Industrial Hydraulics Control Technology Applications in Industrial Hydraulics Proportional Control Valve Applications in Mobile Hydraulics Servo Solenoid Valve Applications in Mobile Hydraulics Field Bus Connection of Hydraulic Components Commissioning and Maintenance. Also includes various color pictures and charts. Published by Robert Bosch GmbH. Distributed by SAE.

This thesis deals with innovative working hydraulic systems for mobile machines. Flow control systems are studied as an alternative to load sensing. The fundamental difference is that the pump is controlled based on the operator’s command signals rather than feedback signals from the loads. This control approach enables higher energy efficiency and there is no load pressure feedback causing stability issues. Experimental results show a reduced pump pressure margin and energy saving potential for a wheel loader application. The damping contribution from the inlet and outlet orifice in directional valves is studied. Design rules are developed and verified by experiments. A novel system architecture is proposed where flow control, load sensing and open-centre are merged into a generalized system description. The proposed system is configurable and the operator can realize the characteristics of any of the standard systems without compromising energy efficiency. This can be done non-discretely on-the-fly. Experiments show that it is possible to avoid unnecessary energy losses while improving system response and increasing stability margins compared to load sensing. Static and dynamic differences between different control modes are also demonstrated experimentally.

The book explores the technology used in proportional valves. The book also describes the construction of electro-hydraulic proportional valve systems, the details of various types of control elements, and the characteristics of proportional valve systems. A fluid power professional should possess exceptional knowledge about proportional valves for his/her continuing professional development and career advancement. A faculty or a student in an engineering institution must acquire the knowledge of proportional valves to upgrade his/her knowledge. As the knowledge and skill of the reader improve, professional life is undoubtedly going to be more outstanding and comfortable.The book has been written by a professional trainer who has vast experience in the fluid power area and trained thousands of professionals and students, over 25 years. If you are looking for a more in-depth knowledge into fluid power, then this book is a valuable resource that will assist you in your quest for professional development.

This book is the second in its series. The book focuses on the electrohydraulic valves in building open-loop and closed-loop control systems. The book also covers the control electronics that drive the EH valves.

This book shows an independent metering electro-hydraulic control system involving its flexible hardware layouts, complex software control, representative products and applications. The book includes one chapter introducing the background and motivation of the independent metering electro-hydraulic control system. It also includes one chapter to summarize various hardware layouts involving the utilized hydraulic components and circuits, as well as analyze their advantages and disadvantages. It emphatically consists of four chapters demonstrating the detailed multivariable control strategies from three levels: load, valve and pump, together with fault-tolerant control under the fault condition. It includes a last chapter, in which products of independent metering control valve and their applications in some typical heavy-duty mobile machinery are collective works of reviews illustrative of recent advances. This book is interesting and useful to a wide readership in the various fields of fluid power transmission and control.