CN101646288A - Dimming method applicable to traditional dimmers and LED dimmable drive power - Google Patents

Abstract

The invention relates to a dimming method applicable to traditional dimmers and an LED dimmable drive power. The method comprises the following steps: converting PWM signals determined by the phase ofthe angle of flow into DC signals through a phase test circuit after being filtered by a RC circuit, and magnifying the signals to control the changes of the resistance value of a constant-current sampling resistor so as to regulate the magnitude of the LED current. The invention can regulate the brightness of an LED bulb by the traditional dimmer, so that people can conveniently change the traditional incandescent bulb lamp into the LED bulb lamp with the ideal stepless dimming function. The LED has the characteristics of long service life, no mercury pollution or ultraviolet pollution, highlight efficiency, shock resistance, energy saving and the like, and belongs to a new generation of green light sources. Therefore, the invention has the advantages of favorable dimming effect (1-100%of continuous stepless dimming), soft light color, environmental protection and energy saving.

Description

Be applicable to the light-dimming method and the LED tunable optical driving power thereof of traditional dimmers

Technical field:

The present invention relates to a kind of light-dimming method and LED tunable optical driving power thereof that is applicable to traditional dimmers.

Background technology:

Traditional dimmer is to transfer the phase place of the angle of flow and brightness is come traditional osram lamp is carried out in the back along the phase place of transferring the angle of flow adjusting by the forward position.The principle of forward position dimmer is, on the input voltage sine wave of every half period, do not allow a part of conducting of front, thereby reduced the mean value of supply power voltage, controls the power of lamp, also just controlled the brightness of lamp.Then the principle along dimmer is, on the input voltage sine wave of every half period, does not allow a part of conducting of back, thereby has also reduced the mean value of supply power voltage, so also can control the power of lamp, has promptly controlled the brightness of lamp.

Led light source is novel light source, need power to it with low-voltage DC, existing civil power can not be directly to its power supply, so need a switch power converter to come the voltage of transformation electric current to power to LED, we are called driving power this power supply, if the civil power through traditional dimmer is directly inserted this driving power, so when phase conduction angle changes, the electricity of storing in the electric capacity can continue the work of LED in the dead band of the angle of flow, the result causes when the angle of flow is bigger can not light modulation, to deposit the intact line voltage fluctuation that causes of tele-release too big owing to electric capacity when the angle of flow is very little, repeats significantly to discharge and recharge and cause the flicker of LED.In technology in the past, all do not address this problem well.The narrow range that is not light modulation is exactly that working temperature is too high, and perhaps the LED peak current is too big.

In recent years, there is the designer to do the experiment (controllable silicon dimmer belongs to a kind of of forward position phase modulation) of carrying out the LED light regulating technology with controllable silicon, still, all there is certain problem in these experiments, such as, 1) bad to traditional dimmer versatility, can only rely on the dimmer of individual brand; 2) caloric value is big, and the product of making is unreliable; 3) dimming effect is bad, minimumly can only be transferred to 20%, if when brightness is low again, the stroboscopic of light will be very serious, and perhaps the designer just turn-offed it before the flicker of LED lamp, can not satisfy the requirement of daily life to dimmer like this.

Summary of the invention:

The objective of the invention is to overcome the deficiencies in the prior art, realize regulating to such an extent that be applicable to the light-dimming method and the LED tunable optical driving power thereof of traditional dimmers the ideal of the brightness of LED bulb thereby provide a kind of phase place to control current value by LED with the angle of flow

For achieving the above object, technical scheme provided by the invention is: the light-dimming method that is applicable to traditional dimmers, this method is to pass through phase detecting circuit, becoming direct current signal behind the pwm signal process RC circuit filtering by angle of flow phase decision, this signal is amplified the variation of controlling constant current sample resistance resistance afterwards, reach the size of regulating the LED electric current.

A kind of LED tunable optical driving power based on above-mentioned light-dimming method design, this power supply includes and it is characterized in that, and this power supply includes:

Dummy load circuit: use one or the series connection of several dummy resistances, make traditional dimmers jump to the operating state that the angle of flow is kept the normally of dimmer when minimum at dimmer;

Rectification circuit: alternating current is converted into Rectified alternating current;

Phase detecting circuit: be used to detect the angle of flow of dimmer, and it is converted to and the corresponding pwm signal of phase conduction angle, convert corresponding d. c. voltage signal to by filtering then, control the size of current of LED lamp with this signal;

Energy storage circuit: during controllable silicon closes the angle of rupture, energy for led light source work is provided for the high frequency switch power transducer, the electric current that guarantees to supply with LED is a constant DC, and the effect that has power factor correction and filtering concurrently;

Switch power converter: promptly be converted to the constant current direct current that is fit to led light source work by the filtered direct current in commercial power rectification, the numerical value of constant current is decided by the resistance of sample resistance, provide with this and to meet the current/voltage numerical value of led light source to the requirement of electric current and voltage, the numerical value of sampling constant current resistance is controlled by phase detecting circuit;

LED current control circuit: in the constant current switch power supply changeover device, magnitude of voltage on the current sampling resistor comes the size of electric current on the induction LED as signal, and control the size that LED goes up electric current with this resistance value, by control the size of sampling resistor with the induced phase of dimmer, regulate the size of the constant operating current of led light source, be the height of brightness, i.e. the constant direct-current working volts value of the corresponding LED of the angle of each phase place.

The present invention has the following advantages and effect: can realize that traditional dimmer carries out brightness regulation to the LED bulb, make people be replaced with LED bulb light fixture to traditional incandescent lamp bulb light fixture easily and the function of stepless desirable light modulation is still arranged, it is long that LED has the life-span, no mercury pollution and ultraviolet ray are polluted, the light efficiency height, vibration resistance, characteristics such as energy-conservation.Therefore the green light source that belongs to a new generation uses the present invention to have good dimming effect (continuous stepless light modulation 1%-100%), photochromic soft, the advantage of environmental protection and energy saving.

Description of drawings:

Fig. 1 is a functional-block diagram of the present invention.

Fig. 2 is applicable to the LED tunable optical driving switch power principle figure of various traditional dimmers for preferred embodiment of the present invention.

Embodiment

Better embodiment of the present invention is: as Fig. 1, shown in Figure 2, voltage after the cut of civil power process traditional dimmers, be added to the input two ends of LED tunable optical power supply, sub-fraction forms the loop through the R1-5 dummy load, be used to continue the silicon controlled conducting, another is most of, and rectification becomes Rectified alternating current later on through D1-D4, wherein sub-fraction is by R6, ZD1 is transformed into it according to what pwm signal of cut, become direct current signal after this signal process RC filtering, again through amplifying the variation of the sample resistance of controlling constant current afterwards, the numerical value of sample resistance feeds back to switch power converter and has just determined LED to go up the size of the constant current numerical value of electric current, can realize at last controlling the numerical values recited that LED goes up constant current with phase place, thereby realize controlling the size of electric current on the led light source, also just controlled the height of brightness, thereby the stepless dimming effect (dimming scope is from 1%-100%) of realizing ideal with the phase place of the traditional dimmers angle of flow.

Use through offering switch power converter behind the D5 through the most of energy behind the over commutation, D6, D7, D8, C1, C2 constitutes filtering and energy storage circuit, at the dimmer blocking interval, provides the energy of work to switch power converter.

The constant current control method of switch power converter belongs to disclosed mature technology, and this specification no longer relates to description, and core of the present invention is exactly the size of coming the output constant current of control switching transducer with the phase place size of the traditional dimmers angle of flow.The numerical value of a corresponding constant electric current of the angle of flow, angle of flow difference, constant current value is different!

Claims (2)

1, is applicable to the light-dimming method of traditional dimmers, it is characterized in that: this method is to pass through phase detecting circuit, becoming direct current signal behind the pwm signal process RC circuit filtering by angle of flow phase decision, this signal is amplified the variation of controlling constant current sample resistance resistance afterwards, reach the size of regulating the LED electric current.

2, a kind of LED tunable optical driving power of light-dimming method as claimed in claim 1, this power supply includes and it is characterized in that, and this power supply includes:

Dummy load circuit: use one or the series connection of several dummy resistances, make traditional dimmers jump to the operating state that the angle of flow is kept the normally of dimmer when minimum at dimmer;

Rectification circuit: alternating current is converted into Rectified alternating current;

Phase detecting circuit: be used to detect the angle of flow of dimmer, and it is converted to and the corresponding pwm signal of phase conduction angle, convert corresponding d. c. voltage signal to by filtering then, control the size of current of LED lamp with this signal;

Energy storage circuit: during controllable silicon closes the angle of rupture, energy for led light source work is provided for the high frequency switch power transducer, the electric current that guarantees to supply with LED is a constant DC, and the effect that has power factor correction and filtering concurrently;

Switch power converter: promptly be converted to the constant current direct current that is fit to led light source work by the filtered direct current in commercial power rectification, the numerical value of constant current is decided by the resistance of sample resistance, provide with this and to meet the current/voltage numerical value of led light source to the requirement of electric current and voltage, the numerical value of sampling constant current resistance is controlled by phase detecting circuit;

LED current control circuit: in the constant current switch power supply changeover device, magnitude of voltage on the current sampling resistor comes the size of electric current on the induction LED as signal, and control the size that LED goes up electric current with this resistance value, by control the size of sampling resistor with the induced phase of dimmer, regulate the size of the constant operating current of led light source, be the height of brightness, i.e. the constant direct-current working volts value of the corresponding LED of the angle of each phase place.

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