PHASE CONTROL METHOD IMPROVING POWER FACTOR OF ELECTRIC HEATER, AND HEATING SYSTEM OF ELECTRIC EATER WITH IMPROVED POWER FACTOR

摘要

PROBLEM TO BE SOLVED: To restrain the economic loss due to utilization of electric power to the utmost when using a plurality of electric heater. SOLUTION: The power factor of total electric heater is improved by managing N units of electric heaters as a group by a central processing device and a power source control device, and by controlling the load and volume of the alternating current flowing through the electric heaters so that the phase angle of respective electric heater becomes continuous with each other.