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 through rectifying circuits, then transforms the DC into a high-frequency current of 10-40kHz via control circuits. As the current flows through the coil, it generates a varying alternating magnetic field. When the alternating magnetic lines within the field pass through ferromagnetic materials (such as iron, cobalt, and nickel), numerous small eddy currents are induced within the metal, causing the metal to self-heating at high speed, thereby achieving the purpose of heating the metal material.
Inverters are the core components of high-frequency electromagnetic heating systems, serving as control devices that convert AC power sources into electricity of another frequency using the on-off action of power semiconductor devices. The inverters currently in use mainly adopt an AC-DC-AC conversion method, first converting the AC power source into DC power through a rectifier, and then converting the DC power into AC power with controllable frequency and voltage to supply to the motor. The inverter circuit typically consists of four parts: rectification, intermediate DC section, 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 section is for filtering, DC energy storage, and buffering reactive power.
Electromagnetic heating advantages:
Energy-saving, precise temperature control, long lifespan, improved working environment, safe and reliable. Utilizes internal heat heating method, where the molecules inside the heating body directly感应 magnetic energy to generate heat, resulting in extremely fast heat-up, with an average preheating time reduced by over 60% compared to other heating methods. The thermal efficiency reaches above 97%, achieving energy savings of 30% to 70% under the same conditions. The electromagnetic heating coil section features a ring 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 uniform, 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.
