| 摘要 |
A magnetic-electronic fluorescent lamp ballast is so arranged that the fluorescent lamp is powered simultaneously by two different currents; which two currents are supplied to the lamp by two separate parallel-connected current sources. One current is of 60 Hz frequency and is supplied directly from an ordinary 120 Volt/60 Hz power line by way of an ordinary magnetic reactor. The other current is of 30 kHz frequency and is derived from the power line by way of a frequency converter and is then supplied to the fluorescent lamp by way of a 30 kHz resonant circuit and a high-pass filter. The frequency converter is powered from the power line by way of a capacitive reactor, with the net result being that the power factor of the total power drawn from the power line is very high. The overall ballast is simple and provides for a relatively high efficacy.
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