| As more and more high-power equipments have being used, energy-saving control has been strongly concerned by the International Society. Hydraulic Piling Rig(HPR) is a large diameter piling engineering equipment with high power. Many advanced energy-saving technologies have been applied in developing a new HPR, but it's the key to coordinate individual technology and integrate them together to get the high efficiency energy-saving. Based on the coordination of energy-saving control technologies applied in system, a power matching control method is proved out by means of the theoretic researches, simulation analysis and test evaluation. The main research works are as follows:1. The current researches, developing trends, and problems and issues of energy-saving control technologies used in HPR at home and abroad are investigated and summarized. At the same time, the significance of energy-saving control is stressed and expounded.2. The performance, characteristics, working conditions, principles and reasons of energy-losing for the system are analyzed. A energy -saving strategy, which is based on the combination of fuzzy control about rotational speed feedback, load-limiting control and load-sensing control, is given for the coordination of power matching among the engine, hydraulic pump and load by using of some advanced energy -saving technologies.3. Based on the power control mode with varying duty, a new control method is firstly given to realize the power matching between the engine and the variable pump. It combine the feedback fuzzy control for engine rotational speed with the load-limit control for the variable pump, and eliminate any power storage which is currently used to achieve the power matching. By means of this method, the engine power can be utilized fully and the engine power can be adjusted from 0 to 100 percent rated power within one hundred rev. Finally, the engine rotational speed is stably controlled in an ideal range and the engine power is efficiently used. 4. Focused on the unpredictable load status in a variable working condition, a fuzzy-PID controller with the parameter self-adjustable is designed. A simulation research is processed to adjust the parameters dynamically, which are used in feedback fuzzy control in rotational speed of engine with the applications of fuzzy toolbox of Matlab simulation software. The results of simulation show a steady rotational speed control can be achieved. Then, a new mathematic model is firstly established for the power matching between the engine and the variable pump to steadily control the rotational speed of engine. Finally, with fuzzy-PID control or PID control or just ordinary control, the effects about steady control of the rotational speed of engine are evaluated through the simulation analysis with Simulink tool of Matlab software.5. After analyzing the principle of power matching control in a double positive flow control pump and multi-loop system, a control method is designed to realize power exchanging and utilization. This method combines the electro-hydraulic proportional stroke displacement control technique with load sensing of all pumps, achieves the coordination and matching control about the system power. It can re-distribute the engine power dynamically when work condition of system is changed, thus the output power of engine can be utilized efficiently.6. After studying the performance and characteristic of rotary system, a load-sensing power control method is put forward to achieve energy-saving control, which can make power matching between output of variable pumps and working load. The energy-saving effect, the influence of dynamic response and the rotator precision control are analyzed and the validation of energy-saving control is also verified when the energy-saving equipment is installed in a rotary system. Then, based on power bond graph modeling method, a control arithmetic is firstly built to model the dynamic response and performance of the system and the power matching between variable pump and load. By using of Simulink tool of Matlab software, the working process of the rotary system is simulated and analyzed, and the influential principles, which reflect the influence of the adjustment of the pump or valve parameters on the dynamic performance of the system, are obtained. Finally, based on load-sensing control, the validation of the power matching system between pump and load is certificated.7. On a SWDM-20 hydraulic piling rig, a test is finished for the research of power concerted matching. The test results have been proved out that the energy-saving control method is rational, effective and practical.In a word, the design theories and methods for the power matching energy-saving control system in this dissertation have been used in a true hydraulic piling rig and succeeded in realizing concerted application of energy-saving control technologies in the whole system. When the engine power is adjusted from 0 to 100 percent rated power, the margin of power matching between engine and variable pump is limited in 5 percent rated power. The engine rotational speed is stably controlled in one hundred rev with high efficiency of energy utilization. The precision of rotator speed control is limited in 0.187%. Finally, the fuel oil consumption has been reduced 5.7% and the average efficiency of energy utilization has been increased as high as 10% .At the same time, a set of theory and method is offered for the energy-saving control in HPR. It is not only significant in theory, but also very valuable in practice when we design and use a new HPR.
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