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 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 flux lines pass through ferromagnetic materials (such as iron, cobalt, and nickel), countless tiny eddy currents are induced within the metal, causing the metal to heat up rapidly, thereby achieving the purpose of heating the metal material.
The inverter is a core component of the high-frequency electromagnetic heater, a device that uses the on-off action of power semiconductor devices to convert power frequency AC into a controlled power supply at another frequency. Currently, inverters are primarily used in AC-DC-AC configuration, initially converting power frequency AC to DC through a rectifier, and then transforming the DC power into controllable AC power in terms of frequency and voltage for 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-type non-controllable rectifier, the inversion section is an IGBT three-phase bridge-type inverter with PWM waveform output, and the intermediate DC section serves for 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 generation through direct magnetic induction in the heating body, with very fast heat-up, an average preheating time reduced by over 60% compared to other heating methods, and a thermal efficiency of over 97%. Energy-saving up to 30%-70% under the same conditions. The electromagnetic heating coil section uses a ring cable structure, with no heat generation from the cable itself, 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 reduced to a level where it is safe for human touch, improving the working environment in the production site, significantly boosting the enthusiasm of production workers, and reducing ventilation and cooling costs in the factory area 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.
