Research And Development Of Heating System Of Injection Molding Machine Based On Electric-magnetic Induction

With the development of industry, plastic products has been more widely used. In the plastics processing industry, injection molding machine is an important equipment were molded plastics processing. With the increase of consumer plastic products require the injection molding machine is constantly evolving. High-performance, high-precision, high-power, intelligent injection molding machine is the future trend of development.Currently injection molding machine heating system there are two main traditional resistive heating and electromagnetic heating. Resistive heating inefficient and short-lived, and currently on the market performance of the injection molding machine electromagnetic heating system varies, most of the use of design principles cooker, induction heating systems lead to poor stability, low failure rates and higher efficiency issues. The main purpose of this project is to design a reliable injection molding machine induction heating system to meet the needs of the market, and promote the induction heating technology in the plastics processing industry.This paper introduces the principle of induction heating, induction heating analysis of the injection molding machine application advantages. Secondly, the series resonant inverter architecture and parallel resonant inverter structure theoretical analysis and comparison of various power adjustment method introduced, chose a series resonant inverter structure and phase shift PWM power regulation mode, and gives the overall design of the injection molding machine induction heating system.Induction heating system design, this paper describes the system core chip, and the temperature acquisition and processing circuit, a PLL circuit, phase shift control circuit, drive circuit and IGBT to achieve specific human-computer interaction module will be described. It analyzes the PLL frequency tracking module works, the CD4046 phase-locked loop with a phase shift control chip UC3879 used in combination to ensure that the system can work stably biased emotional resonance state, and to achieve a wide range of output power adjustment. As used herein, STM32F103 as the main control chip. FSMC interfaces used to drive the LCD screen, and LCD screen, separate buttons to achieve human-computer interaction. This paper analyzes the driving principle of the IGBT, using an integrated IC chip package HCPL316J designed IGBT drive circuit, and by phase shifting circuit to control the IGBT drive circuits, induction heating systems to ensure the stable operation in the resonant state. In the system software design, this paper presents the design of the system software ideas and processes, combined with the hardware design of the system each module can be achieved. It focuses on the principle of fuzzy PID control algorithm and apply it to the induction heating system to achieve closed-loop control of the temperature of the load. Finally, using MATLAB to load the inverter circuit simulation, and the completion of the analysis of experimental results verify the feasibility of the system, reliability and stability.