First, the construction machinery hydraulic energy-saving technology development status quo analysis

The use of displacement adjustment to implement the mechanical work of complex conditions layout standards, combined with the pressure sensor to ensure the benign match the quality of engine power support, implementation of the volume control of the reform efficiency, minimize internal energy loss problem. At present, this technique has been widely accepted. According to the displacement of controlled objects, reasonable disassembly is implemented, different control methods are used to guide and ensure the output characteristics of variable-displacement pumps under different construction occasions. The overall variable control methods are diverse, Mainly include: displacement control and LS load sensing effect adjustment measures.

Displacement control technology

Displacement control is focused on the equipment to ease the displacement, the use of reasonable pressure to maintain the specific value of displacement, the control program is divided into two positive and negative flow. Positive flow control is mainly to meet the quantitative system of flow control throttling speed to the volume of the transition conditions to maintain the system center equipment operating efficiency, based on the experience of the past comparative analysis, including positive flow control excavator excavator skills, its internal The displacement of the pump is proportional to the pressure change condition of the actual pilot operation. However, due to the structural performance of the shuttle valve set in the control system, the control effect of the positive flow in the system is low, causing the complex effect of the system structural layout and the restriction The speed at which the system responds to work. The negative flow control system, on the basis of eliminating the air flow and throttling losses derived from the six-way multi-way valve, improves the response efficiency of the load sensing system.

2. Load-sensitive control system

Second, with the pump equipment output pressure and flow automatically adapt to the load demand

The hydraulic system efficiency adjustment measures research, LS control mainly through the pump displacement structure of the pressure difference mode to sort out, when the pilot pressure and the spring material pressure effects appear imbalance problem, the variable control system control valve spool There will be offset, so that a certain degree of displacement of the pump reaction [2]. However, there are still some problems with this kind of technical solution. If the valve opening degree is not controlled strictly, the required flow rate of the system will exceed the oil supply capacity of the pump structure. The execution speed of the components in the high-load environment gradually decreases, Coordination of mechanical operations is lost. Based on the above understanding of the technical status of different hydraulic systems, it can provide the necessary system reference solutions for the actual production activities in the later period and ensure the standard efficiency of the operation of the control system center.

Third, the development trend of research

1. Intelligent electro-hydraulic proportional control

In the scope of construction machinery to achieve the voltage ratio of technical adjustments, you can reduce the complexity of the hydraulic signal transmission pipeline range, with the preparation of hydraulic signal transmission parameters can effectively speed up the impact of the system speed, while ensuring that the entire mechanical control of the internal power system implemented more Convenient and flexible.

After deeply monitoring the operating parameters of the hydraulic system, the computer performs energy-saving retrofitting according to the power system under the automatic control technology. At the same time, the computer realizes the semi-automatic operation efficiency as far as possible, and realizes the fault diagnosis and benign diagnosis according to the operating parameters under the monitoring activity to ensure the mechanical performance maintenance Features.

2. Power conversion section of the energy-saving programs

(1) series hybrid system

The engine is not connected with the drivetrain implementation to reduce the complex structure of the internal structure and ensure the stable work of the system in a high efficiency area. The motor adjusts the speed and torque output information according to the load variation law. The generator's power support function can be used to maintain the stability of the work area, ensuring a proportional increase of energy efficiency and emission performance. However, the actual system load capacity is completely dependent on the motor rated power level, the overall speed control requirements are relatively stringent, once the details of any form of deviation, will seriously affect the quality of work.

(2) parallel hybrid system

Its power source comes in two forms: a generator and a motor, and a powertrain connection between the powertrain with the torque synthesizer to ensure that the mechanical operation demands torque from the engine; this structure can also be derived synergistically Driving the driving effect, its main characteristic is the engine and the motor realize the joint drive, to ensure that the power equipment to maintain strong support capabilities, so the control system of the technical requirements, but the overall structure of the building activities do not need to consider the generator equipment, braking links In the recovery of the generator can be properly formulated to improve the details of energy-saving plan planning standards.

According to the current development trend of mechanical energy-saving technologies, the benign matching of power has a very significant impact on the energy-saving efficiency of the system [5]. Including excavator structure design, the simple layout of power collocation does not meet the economic benefits and energy-saving requirements, so the use of variable pump and load-sensitive system for adaptive flow matching, with the pump and the necessary load power regulation to determine the work of the generator The best position; with the engine throttle automatic adjustment function to achieve smooth matching of global power to ensure that the overall energy efficiency and economic costs remain in a relatively reasonable range of values.

Conclusion:

Hydraulics energy-saving technology for construction machinery has now made a good technical reform and adjustment, the computer in accordance with the required flow of the load required pilot pressure detection method of setting to ensure that the boom opening of the control valve port can be reasonable. The research on overall intelligent analysis and treatment is rather complex. However, the ecological rehabilitation strategies at the later stage have a wide range of adaptation prospects. Therefore, careful planning studies are needed to improve the practical significance of economic rectification at the stage and to implement the dual values of the strategic benefits of sustainable development and ecological and environmental protection achievements .