Development of digital control system for medium frequency induction furnaces

2018 International Conference on New Energy and Future Energy System

Hou, Y.J.^1 ; Tian, H.M.^1 ; Qu, X.D.^2 ; Teng, J.Z.^1 ; Liu, G.X.^1 ; Li, Yan^1

Energy Institute, Qilu University of Technology, Shandong Academy of Sciences, Shandong Province Jinan

610225, China^1

State Grid Shanghai Pudong Electric Power Supply Company, Shanghai

200122, China^2

关键词: Control and monitoring systems;    Distributed data mining;    Field simulation;    Induction furnace;    Medium frequencies;    Output control;    Phase-locking;    Trigger architecture;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/188/1/012005/pdf
DOI  :  10.1088/1755-1315/188/1/012005

来源: IOP

【 摘 要 】

Traditional medium frequency induction furnace usually adopts analog circuit, which use the theory of PLL to synchronize the drive signal with the induced current signal, so that the upper and lower devices of each phase leg could be gated simultaneously Besides, some problems appear subsequently such as matching debugging difficulty and high failure rate. This paper describes the effect of the burden on the resonant electromagnetic field and resonant frequency through theoretical analysis and magnet field simulation. Based on this, a control and monitoring system designed by digital passive trigger architecture is proposed, phase locking of which is performed according to the frequency of the system itself, fully ensuring that the thyristor will not be simultaneous. In order to improve the stability of the system, this paper optimizes the inverter output control process. At the same time, a friendly human-computer interaction platform is designed, which can achieve distributed data mining, and improve the quality of the product and find the common problems in the product. Finally, the reliability of the control system is verified by experiments.