High frequency electronic discharge lamp electronic ballast

Abstract

The invention discloses a high frequency electronic discharge lamp electronic ballast. The electronic ballast comprises a power supply filter circuit, a power factor correction circuit and an oscillating circuit, wherein the power supply filter circuit is provided with an output end and an input end, the input end is connected with an external alternating current power supply, and the power supply filter circuit is used for filtering inputted alternating current; the power factor correction circuit is connected with the output end of the power supply filter circuit, and is used for converting the alternating current into a high frequency direct current, and outputting the direct current to the oscillating circuit; and the oscillating circuit is connected with the power factor correction circuit, used for converting high-voltage direct current which is outputted by the power factor correction circuit into high frequency alternating current which is used by the electronic discharge lamp, and used for providing power for the electronic discharge lamp through a resonance circuit. According to the electronic ballast, a PNP-NPN transistor complementary technology is adopted by the high frequency oscillating circuit, and a feedback circuit is added, so that the stability of a dominant frequency is improved, and the accuracy of frequency error is greatly improved.

Description

technical field [0001] The invention relates to an electronic ballast for a high-frequency electrodeless lamp. Background technique [0002] High-frequency oscillation and power output circuits of the prior art such as figure 1 As shown, the 400V DC voltage output by APFC (Active Power Factor Correction, active power factor corrector) passes through filter circuits C11, C12, L1, and C13, and then charges C15 through R13, R12. When the voltage at both ends of C15 is After charging to the trigger voltage of DB3, the conduction current of DB3 returns to the ground through the primary winding of T2; at the same time, the two secondary windings of T2 induce two driving signals with opposite phases and the same amplitude to push Q2 and Q3 to work alternately to output For high-frequency alternating current, D10, D11, D12, and D13 are gate limiting diodes of Q2 and Q3 respectively; L2 and C17 are output (resonant) matching circuits; C16 is an output DC blocking capacitor. The osc...

AI Technical Summary

Problems solved by technology

The oscillation start of this circuit is an RC (resistor-capacitor) oscillation circuit. Its stability is relatively poor, the frequency is not too high, and it is easily disturbed by the power supply; in addition, this circuit has no feedback loop, and the frequency error and load capacity are relatively poor; because of this The design of the circuit is insufficient, and it can only be used in low-end products with low cost, low power and low requirements, and needs to be improved urgently

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