| 摘要 |
An electronic ballast (10) for gas lamp loads, such as ionized lamps, that includes a boost power factor correction (30) used to correct the power fact or and minimize the total harmonic distortion. The boost (30) includes an inductor (31) that periodically stores and discharges its resulting voltage in a charging capacitor (34) through an optional bypass diode (32) connected in parallel with an electronic switch (S1) using the oscillator (40) that is applied to the load. The addition of the bypass diode (32) decreases the tot al harmonic distortion. The inductor (31) is selected, in combination with the rest of the circuit, so that it never reaches saturation. The inductor (31) periodically charges the charging capacitor (21) above (twice) the peak voltage that is supplied by a rectified continuous source of direct voltage. The high intensity discharge load (80) is connected to a suitable resonant circuit (60). The load inductor (31) as well as the elements of the resonant circuit (60) and biasing elements of the oscillator include devices that permit a user to select different values thus affecting the resonant frequen cy.
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