Principle of electromagnetic heater:
An electromagnetic heater is a device that converts electrical energy into heat using the principle of electromagnetic induction. The electromagnetic controller converts 220V/380V, 50/60Hz AC power into DC through a rectifying circuit, then transforms the DC into a high-frequency current of 10-40kHz via a control circuit. As the current flows through the coil, it generates a varying alternating magnetic field. When the alternating magnetic flux lines pass through magnetic materials (such as iron, cobalt, or nickel), countless small eddy currents are induced within the metal, causing the metal to heat up rapidly by itself, thereby achieving the purpose of heating the metal material.
The inverter is a core component of the high-frequency electromagnetic heater, functioning as a control device that converts the power frequency AC power into electricity of another frequency using the on-off action of power semiconductor devices. The inverters currently in use mainly operate in an AC-DC-AC configuration, first converting the power frequency AC power into DC power through a rectifier, and then transforming the DC power into an AC power supply with adjustable frequency and voltage for the motor. The inverter circuit typically consists of four parts: rectification, a middle DC link, inversion, and control. The rectification section is a three-phase bridge-type uncontrolled rectifier, the inversion section is a three-phase bridge-type IGBT inverter with PWM output, and the middle DC link includes filtering, DC energy storage, and reactive power buffering.
Electromagnetic Heating Advantages:
Energy-saving, precise temperature control, long lifespan, improved working environment, safe and reliable, utilizes internal heat heating method, where the molecules within the heating body directly感应 magnetic energy to generate heat, resulting in a very fast heat-up, with an average preheating time reduced by over 60% compared to other heating methods, and a thermal efficiency of over 97%. It saves 30% to 70% of energy under the same conditions. The electromagnetic heating coil section employs a ring-shaped cable structure, which itself does not generate 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 area, significantly boosting the enthusiasm of production workers, and reducing ventilation and cooling costs in the factory during summer. The electromagnetic coil has good insulation properties, eliminating the need for direct contact with the outer wall of the heating body, ensuring safer heating.
