advertisement
Hydraulic and Electric-Hydraulic Control Systems
Introduction
 |
| Hydraulic and Electric-Hydraulic Control Systems |
Force and motion control systems of varying degrees of sophistication have shaped the lives of all individuals living in industrialized countries all over the world, and together with communication technology are largely responsible for the high standard of living prevalent in many communities. The brains of the vast majority of current control systems are electronic, in the shape of computers, microprocessors or programmable logic controllers (PLC), the nerves are provided by sensors, mainly electromechanical transducers, and the muscle comprises the drive system, in most cases either electric, pneumatic or hydraulic.
advertisement
The factors governing the choice of the most suitable drive are the nature of the application, the performance specification, size, weight, environmental and safety constraints, with higher power levels favoring hydraulic drives. Past experience, especially in the machine tool sector, has clearly shown that, in the face of competition from electric drives, it is difficult to make a convincing case for hydraulic drives at the bottom end of the power range, specifically at fractional horsepower level. A further, and frequently overriding factor in the choice of drive is the familiarity of the system designer with a particular discipline, which can inhibit the selection of the optimum and most cost-effective solution for a given application
advertisement
Table of contents
I Introduction
2 Hydraulic Power Source
3 Working Pressures
4 Hydraulic Actuators
5 Control Elements
5.I Pressure Controls
5.2 Flow Controls
6 Data Transmission Elements
7 The Control System
7.I The Controller
7.2 The Closed Loop Option
8 Control Concepts
8.I Definition of Terms
8.1.1 Stability
8.1.2 Transfer Function
8.1.3 Steady-State Gain
8.1.4 Loop Gain
8.1.5 Frequency Response
8.1.6 Stability Criteria
9 Principles of Flow Control for Valve-Operated Systems: Part I
I 0 Principles of Flow Control for Valve-Operated Systems: Part2
I 0.1 Effect of Quiescent Leakage on Linearity
I1 Introduction to System Analysis
12 System Analysis of Electro-hydraulic Control System
13 Modular Optimized System Simulation
14 System Analysis in the Time Domain
15 Transient Response Characteristics
16 Further Case Studies
16.1 Third Order System with Flow Feedback
16.2 Fourth Order Hydrostatic Transmission
16.3 Fifth Order System
16.4 Seventh Order System with Flow Feedback
17 Non-symmetrical Systems
17.1 Oil Compliance
17.2 Cavitation Effects of Overrunning Loads
17.3 Worked Example
18 Response to Large Step Demand
19 Valve Operating Forces
19 .I Spool Valves
19.2 Flapper-Nozzle Valves
19.3 Poppet Valves
20 The Electronic Interface
Download full PDF in Comment section
advertisement
Hydraulic and Electric-Hydraulic Control Systems
ReplyDelete