ABSTRACT
At present time, when the situation of energy conservation is vigorously
promoted, the application of industrial heat treatment is going down with its
disadvantages mainly reflected in the low heating efficiency, energy consumption and
serious environmental pollution. After the emergence of electromagnetic induction
heating the field is trying to use this approach to solve such problems. Cookers are
made based on the principle of electromagnetic induction. However, compared to the
traditional induction heating applications, such as civilian and commercial induction
cookers, the development of the industrial cookers is relatively slow, because of the
fact that people rely much on the traditional mode of electricity and gas heating and
the concept of energy heating is not positively transferred; the technological
innovations of a large part of enterprises are slow, they are unwilling to spend the cost
to solve the fundamental problems of utilization ratio of energy resources. Although
some companies or research institutions are engaged in improving, but the outcome is
unsatisfactory. This, in a large part is reflected in the low efficiency of the appliance
controller, the complexity of circuit topology and the poor operational control. This
paper does not consider the premise of the parameter design of the furnace body, but
specifically focuses on the control mode of the appliance controller circuit topology
and artificial intelligence, etc. a certain amount of research work and the
achievements. The main researches are:
In analyzing the principle of electromagnetic induction, load equivalent circuit
and several inverter topology, a simpler industrial cooker controller is investigated
and designed. Comparative studies have been done to the power conditioning of the
circuit topology of half-bridge series resonant inverter, and fianlly selected the pulse
frequency modulation control of the induction cooker power, thus established the
STM32 for the control of the core controller system overall control program. Power
level circuit design, the modular design concept, carried out a detailed comparative
study on the main circuit and isolation of the specific parameters of the drive circuit
according to the performance indicators. Based on the outcome of the above study,
the circuit control is also detailed designed, including temperature, current, voltage,
man-machine interface, fault alarm, and other aspects of the modular circuit design
and circuit protection must work to improve the safety and reliability of the power
switch.
In terms of temperature control, PID control algorithm has come out with a
cooker temperature PID overall control strategy, the drive pulse frequency modulation,
the system has a better steady state performance, power output of the inverter, and
thus indirectly control the heating of the internal temperature of the furnace, and
achieved the constant temperature control purposes. More popular modular designs