Nadgradnja krmilno-regulacijske elektronike visokofrekvenčnega pretvornika za indukcijsko gretje

Hribar, Gašper (author), Nemec, Mitja (mentor)

V tem dokumentu je predstavljen postopek nadgradnje krmiljenja obstoječega sistema za indukcijsko gretje. Predstavljena je izdelava in implementacija novega krmilnega vezja za krmiljenje visokofrekvenčnega razsmernika. Za izdelavo novega krmilnega vezja smo najprej analizirali specifikacije obstoječega. Ker smo želeli obstoječe krmiljenje tudi nadgraditi, smo naredili vezje, ki je zmožno meriti fazni zamik med napetostjo in tokom razsmernika, z maksimalno napako ±5°. S pomočjo izpolnitve te zahteve rešimo temeljni problem obstoječe regulacije, kar je nezmožnost zaznave vrha resonančne krivulje bremena naprave za indukcijsko segrevanje. V nadaljevanju je predstavljena shema programa mikrokrmilnika za izračun faznega zamika in oblikovanje krmilnih signalov razsmernika. V zaključnem delu so predstavljeni uspešni rezultati praktičnega preizkusa implementacije krmilnega vezja. Poleg FC (angl. frequency control) strategije [1] je prikazana še možnost uporabe PS-PWM (angl. phase shifted pulse-width modulation) metode krmiljenja [1].

• Language: Slovenian
• Keywords: indukcijsko segrevanje, razsmernik, vzorčenje, DFT, fazni zamik, FC, PS-PWM, MCU ...
• Work type: Master's thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2022
• PID: 20.500.12556/RUL-142978
• COBISS.SI-ID: 132728323
• Publication date in RUL: 07.12.2022

Secondary language

• Language: English
• Title: Upgrade of control electronics for high frequency inductive heater

Abstract

This document describes the process of upgrading the control of an existing induction heating system. The design and implementation of a new PCB for the control of the high frequency inverter is presented. To design the new PCB, the specifications of the existing PCB were first analysed. Since we also wanted to upgrade the existing control, we made a PCB capable of measuring the phase lag between the voltage and current of the inverter, with a maximum error of ± 5°. By meeting this requirement, we solve the fundamental problem of the existing control, which is the inability to detect the peak of the resonance curve of the load of the induction heating device. Further, a schematic of the microcontroller program that calculates the phase and generates the control signals for the inverter is presented. In the final part, the successful results of a practical test of the PCB implementation are presented. In addition to the frequency control (FC) strategy [1], the possibility of using the phase shifted pulse-width modulation (PS-PWM) control method [1] is shown.

• Keywords: induction heating, inverter, sampling, DFT, phase, FC, PS-PWM, MCU ...