Energy-efficient hydraulic power supply driven by permanent magnet servo motor

Abstract

The invention discloses an energy-efficient hydraulic power supply driven by a permanent magnet servo motor, which comprises the permanent magnet servo motor, a servo controller, a hydraulic oil pump (comprising a gear oil pump, a vane pump, and a plunger pump), a sensor and the like. An oil pump is driven by the high-efficiency permanent magnet servo motor which has good mechanical characteristic, large overload magnification, and high speed regulation performance; a system for redundancy monitoring of system flow and pressure by pressure-flow double closed loop control and the voltage and current of the motor is adopted; and an oil temperature compensation function is realized. According to different hydraulic pressure load working conditions, three working modes of pressure self-adaption, flow self-adaption, and power self-adaption are provided, and each working mode is optimized by adopting different control strategies. Therefore, the energy-efficient hydraulic power supply has the advantages of wide application range, high system efficiency, high low-speed stability, quick response, accurate speed regulation and the like.

Description

technical field [0001] The invention belongs to the manufacture of hydraulic equipment, in particular to an energy-saving hydraulic power source driven by a permanent magnet servo motor, which can provide hydraulic energy for hydraulic equipment in different working states. Background technique [0002] Hydraulic equipment is widely used in mechanical engineering due to its excellent characteristics such as stable transmission, convenient speed regulation, and large power-to-volume ratio. However, the overall energy utilization rate of the hydraulic power system is not high, and the system efficiency is low. Therefore, the use of energy-saving design to improve system efficiency has become a major concern of hydraulic technology workers. Previous energy-saving designs have focused on the design of hydraulic circuits and the selection of high-efficiency hydraulic components, and have achieved good energy-saving effects. For example, load self-adaptive control is used to mini...

AI Technical Summary

Problems solved by technology

[0004] 1) Many occasions require the motor to drive a large load to start, but the low-speed characteristics of the asynchronous motor are poor, the efficiency is very low at low speed, and the output torque is also small, so in order to drive the load, only Increase the power of the motor;

[0005] 2) Due to thermal inertia, the short-term overload of the motor is allowed, but the overload multiple of the asynchronous motor is relatively low, generally below 2.2, so sometimes a higher-power motor has to be used in order to meet the requirements of the instantaneous larger load;

[0006] 3) The power factor of the asynchronous motor is low, about 0.7~0.9 at rated load, and even lower at light load or no load, only 0.2~0.3;

[0007] 4) The stator current of an asynchronous motor can be decomposed into two parts, one part is the excitation current used to form a magnetic field in the rotor, and the other part is the load current used to output torque, regardless of whether the motor has actual torque output, the excitation current exists , and the proportion of excitation current will be larger at low speed or no load, and the existence of excitation current will consume a certain amount of motor power

The disadvantage is that the system is more complicated, the anti-pollution ability is poor, and the cost performance is not high

[0013] In summary, the inherent defects of traditional hydraulic power sources do not meet the requirements of modern hydraulic systems such as energy saving, high efficiency, sensitivity, and precision. Therefore, the search for new hydraulic power sources has always been concerned by industry insiders.

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