Electronic ballast of novel single-level circuit structure

Abstract

The invention discloses an electronic ballast of a novel single-level circuit structure. The electronic ballast comprises a device for detecting voltage, current and phase of an input AC power supply;a rectifier bridge; a full-bridge inverter circuit; and an inverting control circuit; a serial resonance capacitor Cs and a serial resonance inductor L are further arranged at an output end of the full-bridge inverter circuit when the output end of the full-bridge inverter circuit is used as a gas discharge lamp of the load. By adding the serial resonance capacitor Cs and the serial resonance inductor L in the existing electronic ballast of the single-level circuit structure, the problem that the under-voltage causes the extinguishing of HID due to the zero-crossing point of the one-way sinewave DC can be effectively solved; due to the adding of a conduction angle on the whole one-way sine half-wave by the HID, a PF value is improved, and the harmonic wave is effectively reduced.

Description

technical field [0001] The invention relates to the field of ballasts, in particular to an electronic ballast with a novel single-stage circuit structure. Background technique [0002] At present, electronic ballasts in the field of lighting, including HID electronic ballasts for high-pressure gas discharge lamps, are used more and more, and the main structure is still electronic ballasts with secondary or even tertiary circuit structure. These electronic ballasts are complex in structure and relatively high in cost. Therefore, the applicant has designed an electronic ballast with a single-stage circuit structure (see Chinese patent document CN103369806 B), and the circuit topology of the single-stage ballast is as follows figure 1 As shown, the single-stage ballast includes device chips U3 and U2 for detecting AC input voltage, current and phase; there is also a rectifier bridge D1 composed of 4 diodes, and a rectifier bridge composed of 4 semiconductor switches S1 / S2 / S3 / S...

AI Technical Summary

Problems solved by technology

[0004] The present invention aims at the problem that the current single-stage ballast will lead to unstable HID operation when the sine wave crosses the zero point, and in addition, the harmonics are relatively large and the PF is low, and a new type of electronic ballast with a single-stage circuit structure is provided.

The output terminal of the electronic ballast is connected in series with the resonant capacitor and inductor to overcome the problem that the current single-stage ballast will cause HID to work unstable at the zero crossing point of the sine wave, and in addition, the harmonics are large and the PF is low.

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