摘要 |
An operating circuit and method for efficiently operating and starting an electrodeless lamp having a magnetic core operated at radio frequencies. The circuit generates a current which flows through the winding of an electric field inducing means in the lamp in a reverse-bias direction, with respect to a drive current, to operate the core of the inducing means in all quadrants of the B-H curve, with the time average of all current through the lamp winding equaling approximately zero in order to avoid or minimize heat energy losses and sharp current peaks caused by saturation. This also allows use of lower current-capacity less-expensive components. The circuit repetitively applies constant-current DC drive pulses to the lamp winding for a small percentage of an interval during which energy is stored, which is used to generate the reverse-bias current. Additionally, energy of flyback associated with turning-off of current in the lamp-winding-and-core is maximally limited to the winding itself for facilitating faster starts.
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