Principle of electromagnetic heater:
An electromagnetic heater is a device that converts electrical energy into heat by utilizing the principle of electromagnetic induction. The electromagnetic controller converts 220V/380V, 50/60Hz AC power into DC power through a rectifying circuit, then transforms the DC power into a high-frequency current of 10-40kHz via the control circuit. As the current flows through the coil, it generates a varying alternating magnetic field. When the alternating magnetic lines in the field pass through magnetic materials (such as iron, cobalt, and nickel), numerous tiny eddy currents are induced within the metal, causing the metal to heat up rapidly, thereby achieving the purpose of heating the metal material.
Inverters are the core components of high-frequency electromagnetic heaters, functioning as power control devices that convert power from the standard frequency AC source to another frequency using power semiconductor devices. The inverters currently in use primarily operate in an AC-DC-AC configuration. They first convert the standard frequency AC power into DC power through a rectifier, and then transform the DC power into AC power with adjustable frequency and voltage for the motor. The inverter circuit typically consists of four parts: rectification, intermediate DC link, inversion, and control. The rectification section is a three-phase bridge uncontrolled rectifier, the inversion section is an IGBT three-phase bridge inverter with PWM waveform output, and the intermediate DC link handles filtering, DC energy storage, and reactive power buffering.
Electromagnetic Heating Advantages:
Energy-saving, precise temperature control, long lifespan, improved working environment, safe and reliable, utilizing internal heat heating method, where the molecules inside directly sense magnetic energy to generate heat, resulting in a very quick heat-up time. The average preheating time is reduced by over 60% compared to other heating methods, with a thermal efficiency of over 97%. It saves energy by 30% to 70% under the same conditions. The electromagnetic heating coil section features a circular cable structure, with the cable itself not generating heat, resulting in minimal thermal resistance and low thermal inertia. The outer wall temperature of the heating body is consistent, with real-time and accurate temperature control, and can withstand temperatures above 500°C, with a lifespan of up to 10 years. The surface temperature of the equipment can be improved to a level where it is safe for human touch, enhancing the working environment in the production site and significantly boosting the enthusiasm of production workers, while reducing ventilation and cooling costs in the factory area during summer. The electromagnetic coil has excellent insulation properties, eliminating the need for direct contact with the outer wall of the heating body, ensuring safer heating.
