Injection molding electromechanical servo system technology and application (3)

For specific applications of injection molding machines, Yueneng has developed a series of dedicated control algorithms:
A. Introduce the modern nonlinear control method into the motor field orientation control algorithm to eliminate the nonlinear influence of the reluctance motor parameters, and optimize the design of the motor and the controller to realize the precise control of the output torque of the permanent magnet-reluctance servo motor. .
B. For the characteristics of pressure fluctuations of gear pumps and piston pumps, a Noise Cancellation control method is used to reduce the fluctuation of the pump output pressure.
C. Because the system frequently switches between flow control and pressure control modes, the fuzzy control principle is used to achieve a smooth transition between flow and pressure control.
D. Use flow control with pressure compensation to eliminate the effect of pressure on the accuracy of flow estimation.
E. Using sliding mode variable structure and other nonlinear control methods to make the system quick response and small overshoot.
F. Weak magnetic control algorithm is adopted. The system has better high-speed characteristics and wider speed range.
G. Load parameter adaptive algorithm, so that the system can adapt to a variety of oil pumps.
H. Due to the nonlinear characteristics of the given signal, a given correction algorithm was designed to match the system's excellent low-speed control characteristics, effectively solving the low-speed crawling problem of the injection molding machine.
Test results Yueneng servo electro-hydraulic system has received energy-saving, high-efficiency, and precise results in the application of injection molding machines.

Figure 3 shows the system efficiency map (including the controller and motor) of Yueneng servo system. The maximum efficiency is over 91%, and the high efficiency area (more than 85% of the area) is very wide. It can be seen that the energy saving effect is significant.
The figure on the right shows the repeatability chart of the product tested at a customer's factory in Dongguan. It can be seen from the figure that the product weight repeat error is < 3%. The testing machine used was 190 tons, the system pressure was 160bar, the servo motor was KT-TM-1802-DF, the oil pump was Push BK55, the displacement was 55.5cc/rev, and the servo controller was KT-CT-1802-A-0. (To be continued)