CN102421236A - CFL electronic ballast capable of adjusting voltage and light - Google Patents

Abstract

A voltage-adjustable and dimming CFL electronic ballast includes a rectifier and filter circuit module, a switch circuit module, and a ballast output circuit module. The rectifier and filter circuit module is connected to the switch circuit module, and the switch circuit module is connected to the ballast output circuit module. The switch circuit module is composed of a half-bridge IC and a frequency control circuit. The switch circuit module converts a DC voltage into a high-frequency AC voltage. The ballast output circuit module is composed of a first transformer and a sixth capacitor connected in series. The voltage-adjustable and dimming electronic ballast of the present invention is matched with a voltage regulating device, which can realize the collective voltage regulation and dimming of CFL energy-saving lamps in the corresponding area, and is suitable for commercial lighting occasions such as shopping malls, hospitals, and hotels.

Description

A CFL electronic ballast with adjustable voltage and dimming

technical field

The invention relates to an electronic ballast, in particular to a CFL electronic ballast with adjustable voltage and light.

Background technique

In the field of lighting, incandescent lamps have been banned by governments of various countries due to their excessive energy consumption and low lumen coefficient, and they have been replaced by fluorescent lamps (commonly known as fluorescent lamps and various energy-saving lamps). However, fluorescent lamps still consume a lot of electricity, especially in factories, shopping malls, hotels, stadiums and other large public places and municipal roads. By adopting effective lighting energy-saving technology and control devices, the lighting load can be reduced and unnecessary lighting time can be reduced. and lighting intensity. On the one hand, it can save a lot of power consumption, and on the other hand, it also greatly reduces maintenance costs. At present, the voltage regulation and dimming method is commonly used in lighting energy-saving equipment at home and abroad, but the application of products with good dimming effect and high cost performance is very rare at home and abroad. CFL is small in size and cheap in price. It is the most widely used fluorescent lamp terminal product in commercial office lighting. Adding adjustable dimming function to CFL, multiple or multiple groups of CFLs can be concentrated and matched with voltage regulators to perform lumped voltage regulation and dimming. Has a very good market prospect.

Contents of the invention

The technical problem to be solved by the present invention is to provide a voltage-adjustable and light-adjustable electronic ballast, which has the characteristics of adjustable line input voltage from 9100V to 240V, good linearity in dimming, compact structure, and high cost performance.

The above object of the present invention is achieved by such a technical solution: a CFL electronic ballast with adjustable voltage and light, including a rectification and filtering circuit module, a switching circuit module, a ballast output circuit module, and a rectification and filtering circuit module connected to The switch circuit module is connected to the ballast output circuit module. The switch circuit module is composed of a half-bridge IC and a frequency control circuit. The switch circuit module converts the DC voltage into a high-frequency AC voltage. The ballast output circuit module is composed of a first transformer and a sixth capacitor connected in series.

The frequency control circuit of the switch circuit module is grounded after the frequency setting pin of the half-bridge IC is connected to the fifth resistor, and the working frequency of the switch circuit module is determined by the resistance value of the fifth resistor.

The first transformer is a magnetic leakage step-up transformer, and the leakage inductance of the first transformer, the equivalent resistance of the CFL and the seventh capacitor form a resonant circuit.

The step-up ratio of the first transformer is between 1:4~1:6, and the adjustment range of the input voltage is greater than: 100V~240V.

The beneficial effects of an electronic ballast for voltage regulation and light adjustment of the present invention are as follows:

1. Matching voltage adjustment device can realize lumped voltage regulation and dimming of CFL energy-saving lamps in the corresponding area, and is suitable for commercial lighting occasions such as shopping malls, hospitals, and hotels.

2. Large dimming range, good linearity, and remarkable energy-saving effect.

3. The circuit is simple, the structure is compact, and it can be implemented on a PCB with a diameter of 37.5 mm. It matches the supporting components of ordinary energy-saving lamps. The circuit is cost-effective and has the potential for large-scale promotion and application.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the present invention is further described:

Fig. 1 is a circuit diagram of the present invention;

Fig. 2 is an equivalent circuit diagram of the resonant circuit of the present invention.

Detailed ways

As shown in Figure 1, a CFL electronic ballast with adjustable voltage and dimming includes a rectification and filter circuit module, a switch circuit module, a ballast output circuit module, the rectification and filter circuit module is connected to the switch circuit module, and the switch circuit module is connected to the ballast Stream output circuit module. The switch circuit module is composed of a half-bridge IC and a frequency control circuit. The switch circuit module converts DC voltage into high-frequency AC voltage. The ballast output circuit module is composed of a first transformer T1 and a sixth capacitor C6 connected in series.

The frequency control circuit of the switch circuit module is grounded after the frequency setting pin of the half-bridge IC is connected to the fifth resistor R5, and the working frequency of the switch circuit module is determined by the resistance value of the fifth resistor R5.

As shown in Figure 2, the first transformer T1 is a magnetic leakage step-up transformer, the leakage inductance L1 of the first transformer T1, the equivalent resistance Rlamp of CFL and the seventh capacitor C7 form a resonant circuit.

Where L1 is the equivalent total leakage inductance of the primary and secondary of the first transformer T1. The step-up ratio of the first transformer T1 is between 1:4~1:6, and the allowable adjustment range of the input voltage is greater than: 100V~240V. Usually the fluorescent tube has a Voff voltage, which is the repeated ignition voltage. The lamp will not flicker or go out only when it works above the Voff voltage. When the ordinary CFL electronic ballast adjusts the output voltage, the V rms will drop accordingly. When adjusting lower than Voff, the lamp will flicker or go out. After adopting the leakage inductance step-up transformer, the voltage of the switching circuit increases from Vrms to nVrms after passing through the first transformer T1, 4≤n≤6, which can be set according to the adjustment range. When the ballast input voltage changes, Vrms will decrease, but as long as the pre-designed nVrms>Voff, since the total impedance of the circuit remains unchanged, the output current of the ballast output circuit module changes linearly with the voltage, the brightness of the lamp decreases with the current, and the illuminance output decreases , so as to realize voltage regulation and dimming.

Example:

Take the 7W adjustable voltage and dimming CFL electronic ballast as an example: it includes a rectification filter circuit module, a switch circuit module and a ballast output circuit module. The IC frequency setting pin of the switching circuit module is connected to the fifth resistor R5 and then grounded to GND to form a switching frequency control circuit. The switching frequency of the switching circuit is set by the resistance of the fifth resistor R5. The half-bridge IC chip uses IMP3521, or FAN7387, or IR2153.

The first transformer T1 is a magnetic leakage step-up transformer, and the leakage inductance of the first transformer T1, the equivalent resistance Rlamp of the CFL and the seventh capacitor C7 form a resonant circuit. The step-up ratio of the first transformer T1 is 1:4. The power input frequency is 50HZ, the voltage range is 100~240V, and the electrical test of the CFL lamp is as follows:

                                                 

Carry out a light efficiency test on the whole CFL lamp, and see the appendix for the test results. The whole lamp power is 7.4W, the color temperature of the lamp tube is white 6436K, the color rendering index is 83.8, and the luminous efficiency is 52.958lm/w, exceeding the national secondary energy efficiency standard. The photoelectric performance of the whole lamp is close to that of the CFL electric light source using traditional electronic ballasts.

CFL: Compact Fluorescent Lamp.

Claims (5)

1. A CFL electronic ballast with adjustable voltage and dimming, comprising a rectification filter circuit module, a switch circuit module, a ballast output circuit module, the rectification filter circuit module is connected to the switch circuit module, and the switch circuit module is connected to the ballast output circuit module ; It is characterized in that: the switch circuit module is composed of a half-bridge IC and a frequency control circuit, the switch circuit module converts the DC voltage into a high-frequency AC voltage, and the ballast output circuit module is composed of the first transformer (T1), the second Six capacitors (C6) are connected in series. 2. A kind of CFL electronic ballast with adjustable voltage and dimming according to claim 1, characterized in that: the frequency control circuit of the switch circuit module is composed of the frequency setting pin of the half-bridge IC and the fifth resistor ( R5) is connected to the ground, and the operating frequency of the switch circuit module is determined by the resistance value of the fifth resistor (R5). 3. A CFL electronic ballast with adjustable voltage and dimming according to claim 1, characterized in that: the first transformer (T1) is a magnetic flux leakage step-up transformer, and the leakage inductance of the first transformer (T1) The volume (L1), the equivalent resistance of the CFL lamp and the seventh capacitor (C7) form a resonant circuit. 4. A CFL electronic ballast with adjustable voltage and dimming according to claim 1, 2 or 3, characterized in that: the step-up ratio of the first transformer (T1) is 1:4~1:6 Between, the adjustment range of the input voltage is greater than 100V~240V. 5. A dimming method for a CFL electronic ballast according to claim 1, characterized in that: after the input voltage changes, the leakage inductance (L1) of the first transformer (T1) remains unchanged, and the total impedance of the circuit remains unchanged , the output current of the ballast output circuit module changes linearly with the voltage, and the voltage at both ends of the lamp tube is always higher than the ignition voltage.

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