The Design And Implementation Of CNC Plastic Machine Induction VHF Power

With the plastic industry increasingly fierce competition, in order to reduce product cost, in the guarantee raw material high quality and low price, be able to saving energy, high technology and high degree of automation of plastic machinery plastic processing enterprises to become the first choice to introduce the equipment. In this paper, changed former traditional the plastic mechanical heating wire heating way, proposed one kind of a heating system by use electromagnetic induction technology, enhanced the plastic machinery operating performance, has saved the energy cost.This paper first introduced the domestic and foreign plastic machinery industry in the development of the heating system and electromagnetic induction heating technology in principle, has analyzed the series-parallel resonant inverter topology and characteristics. According to the application of plastic machinery industry practice, focused on an analysis of parallel resonant inverter load characteristics and control objectives, proposed the main circuit uses the single-valve zero type accurate resonance inversion electric circuit in the plastic machinery heating system the way, and has carried on the detailed analysis to this way each kind of active status, for the soft switch control plan proposed provides the theory basis. In the control circuit part, introduced the synchronization oscillating circuit, driver circuit and a variety of auxiliary detection circuit and protection circuit to solve the current control system of induction heating of a number of shortcomings exist, design a low loss, constant power, constant temperature control system so that the product has become a high-efficiency, high reliability, high accuracy, low power loss of the new heating control system.In this paper, LC electromagnetic vibration, IGBT driver and protection, loss control and constant power control hardware has conducted the thorough research and the experiment, has given the main parameters of the method of selection, as well as anti-jamming; Used the synchronizing circuit to realize the invertor operating frequency automatic tracking, designed a better driver and IGBT protection circuit for IGBT easily damage because of overheating and over-voltage, proposed the solution, caused the induction heating control system reliable work. Proposed one internal vibration way has realized the resonance frequency track from the software, and analyzed and has designed this electric circuit start program. In the software design of the control system, in accordance with the functions of the entire system divided into several modules, then carries on detailed and the thorough design to each module, and proposed a PID temperature control methods. Finally, through to the system experimental debugging indicated the system satisfies the practical application request, reliable operation and accurate, suit in promotes in the plastic machinery industry.