Analysis and solution of insufficient power supply for electronic lighting switch

Analysis and Solution of Insufficient Power Supply of Electronic Lighting Switch Xu Jintian, Hengshui City, Hebei Province, Hengshui City, Science and Technology Information Institute, analyzes the causes of insufficient power supply of electronic lighting switches of several kinds of electric lighting solutions, and gives effective and effective solutions. Method.

Introduction Electronic lighting switches are new types of lighting control devices that have emerged in recent years. They are divided into outdoor switches and indoor switches. Currently, most of the commercially available products are for outdoor public lighting. The time delay is self-illuminating, and the switch is controlled by the light. The switch often has insufficient power supply to the load due to poor juice setting, which makes the light bulb dim or flashing, which not only affects the lighting quality, but also the harmonics. The large content has an impact on the quality of power supply, and interferes with the normal operation of other electrical appliances. This paper will analyze the causes of this phenomenon and give a solution.

1 two-way controllable Gui single guide pass caused by dim and flickering phenomenon 1.1 Analysis of the electronic switch controllable silicon to do circuit on-off actuators, which are used to supply power to the control circuit using a capacitor step-down rectifier circuit The parallel type switch is often made into a lamp holder type. Figure 1 shows the power supply of the switch and the common circuit scheme for triggering the execution. The dimming of the light bulb is caused by insufficient power supply voltage. The direct cause of the flashing of the light is that the power supply voltage jumps unstable. When the mains supply is normal, the source of insufficient power supply and unstable voltage jump can only be from the circuit related to the bidirectional controllable switch of the switch actuator. The bidirectional controllable is a kind of controllable component with double conduction. The minimum value of the trigger current required for most two-way controllable forward and reverse conduction is different. When the trigger current shown in Figure 1 is triggered by the trigger pole inflow mode, the minimum trigger current required for reverse conduction is higher than the trigger current required for forward conduction. The difference varies depending on the component. The two-way controllable positive and negative conduction trigger currents are relatively close, and some of them are very different, even if the difference is 231. If the trigger current provided by the control circuit is relatively small, the two-way controllables with the lowest value of the reverse conduction trigger current will be There is only a phenomenon of forward conduction and reverse turn-off, which causes the bulb to be powered by half-wave, which makes the light dim and does not reach normal brightness. For those two-way controllable cells whose reverse-triggering trigger current is close to the trigger current provided by the control circuit, reverse-time-on-time breakage may occur, and the bulb may be fully wave-powered and sometimes half-wave-powered to make the bulb supply voltage. The jump is unstable, and the flashing of the light occurs. When the ambient temperature is lowered, the triggering characteristic of the two-way controller can be delayed, the minimum value of the required trigger current becomes larger, and the chance of dim lighting and flashing of the light is more. . When the weather is warm, this phenomenon will be slower. 1.2 Solution 1 Do the component testing and screening before the production of the product, and remove the two-way controllable cells with the lowest value of the reverse-triggering trigger current for the cold regions in the north. Electronic switch, in production, it is necessary to strictly control this off 2 to reduce the resistance of the 3 in Figure 1 or to increase the stable voltage of ZD, to increase the trigger current provided by the control circuit but sometimes reduce the resistance Still can not make the two-way controllable baby reverse conduction, the voltage at the output of the control circuit may drop, the reason is that the power supply part of the power supply is insufficient, and the step-down capacitor should be increased at this time. The capacity is as good as 9914 plus. 346. 1.1. Foot 16 her. 1. Oil speaks buds [Today's hongshuangpankou Gezhijiao how to add should not be less than 033f for TL336 and other 3A two-way controllable silicon, the capacitance should not be less than 0.5妒2 2 when the circuit design position is fixed The power supply is gradually weakened. The timing of the design timing circuit is not good, except that it will affect the accuracy and stability of the illumination delay. Sometimes the output voltage of the switch will gradually decrease, making the light darker. Figure 2 shows some delays. The circuit used for the switch, the calibration trigger execution circuit is directly connected. When the lamp is not required to be illuminated, the capacitor has no charge storage, and the controllable controller can not obtain the trigger current. When the signal is turned off, the control circuit is required to be turned on. The output terminal is at a high potential, charged, and then passed through the triggering pole discharge of the controllable baby, so that the controllable baby is turned on and the bulb is illuminated. As the charge is released, the trigger current supplied to the controllable watt is gradually reduced. When the trigger current is insufficient to trigger the controllable baby, the controllable baby will be turned off and the bulb will be extinguished. Obviously, the length of the bulb illumination delay time is related to the sensitivity of the controllable triggering characteristic. The triggering characteristic is too pure. The trigger current may be slightly reduced, and the bulb lighting time may be shorter. For those triggering characteristics, Very sensitive controllable baby, even if the discharge current of 0 becomes very small, the controllable lung can be turned on, the bulb illumination duration can be longer, the electronic switch of this scheme is judged, and the luminous extension of the same batch of products The dispersion degree may be very large. When using different power bulbs, the temperature of the controllable watts is different, so that the change of the trigger sensitivity is the accuracy current of the illuminating delay, and the trigger current is gradually reduced when the trigger current is small. At the same time, some controllable cells will be shut down immediately, while others will require a slowing process to cause the light to darken. Tests have shown that there are quite a few models of controllable Gui with the characteristics that the trigger current decreases with the increase of the anode voltage. Under the same trigger current condition, the anode voltage is low and the anode voltage is increased. Can trigger the conduction. When the controllable watt with this triggering characteristic works under the condition of decreasing trigger current, the conduction state will have a gradual change process. In the initial stage of discharge, the trigger current supplied to the controllable watt is sufficient. The singularity of the sacred sacred sacs is normal, and the voltage waveform of the controllable baby and the bulb is shown in Figure 3. This state can last for a while. When the trigger current is reduced to a certain extent, the initial voltage of the controllable anode pulse DC voltage starts from zero. Since the anode voltage is low, the controllable silicon can not conduct, and the anode pulse voltage gradually rises with time. The required trigger current value will be reduced. When the anode voltage is high enough, the controllable body can trigger the conduction. At this time, the anode voltage of the controllable lung falls immediately, and the pulse voltage is applied to the bulb to make the bulb. Due to the delay of the conduction time of the controllable baby, only part of the time of each pulse voltage waveform is turned on, the power supply time of the bulb is shortened, the energy is reduced, and the light is dimmed. With the gradual decrease of the trigger current, the anode voltage required for the controllable silicon is gradually increased, and the conduction time is improved and moved backward, so that the power supply time of the bulb is shortened, the illumination continues to be darkened, and the waveform is shown in Fig. 36. After reaching a certain level, as the discharge current of capacitor 0 is further reduced, the anode voltage required for the controllable silicon to conduct is higher, but when the amplitude of the pulsed DC voltage reaches a peak, it decreases. Can not meet the controllable conditions of the controllable baby, the controllable baby is completely turned off, the pulse voltage is all added to the controllable shoes, the bulb is de-energized, the waveform is shown in Figure 31. The trigger current is gradually reduced. The controllable anode voltage waveform of the bulb supply waveform is controlled. 2 The lamp voltage and the controllable 畦 anode voltage waveform are dispersive due to the trigger sensitivity of the controllable watt, and the triggering characteristics vary with the anode supply voltage, so that the light is dimmed late, the duration The length of the same batch of products is different. The controllable controllable doll with a triggering characteristic can delay the moment when the light is dimmed, but the lighting delay time is longer. Relatively speaking, the light is darkened. The time for working will also be longer with the controllable baby that triggers the delay. The time when the light is dimmed is early. Because the lighting delay is short, the time is short in the low-light state, and the light is effectively reduced or eliminated. As the light dims, it seems that only controllable silicones whose trigger characteristics do not change substantially with the anode voltage are selected, but this method is difficult to operate in tissue production. The author believes that the circuit scheme of Figure 2 is difficult to ensure the quality of the product, the national lighting electrical equipment into the design, the timing circuit and the trigger circuit are separated is necessary 3 due to the lack of power supply of the control circuit caused by the darkening phenomenon 3.1 Cause analysis In the series type switch, when the switch is in the state of the lamp, the switch receives the AC voltage at both ends, and when the control circuit in the switch can obtain sufficient power supply light, the AC voltage is substantially applied to the bulb, the switch is in the path state, and the voltage drop at both ends is extremely small. The control circuit inside the switch may lose the effective power supply, causing the control circuit to have a low supply voltage, causing a series of problems. Therefore, the design difficulty of the series electronic switch is how to ensure that the control circuit has sufficient and stable DC supply voltage when the voltage at the switch input terminal is close to zero. The circuit shown in Fig. 4 is not considered in this respect.

The series-type switching circuit is seen in Figure 4. When the switch is actuated, the output of the control circuit is at a high potential. The anti-directional controllable silicon provides sufficient trigger current to make the controllable shoes conductive, and the AC mains through the bulb, rectifier bridge and The controllable circuit forms a loop, and the bulb is fully voltage-operated. The normal state of the bulb can be controlled to be in a conducting state. The voltage between the two ends is lower than lV, and the AC voltage between a and b is also very low. The sum of the forward voltage drop of the tube and the controllable watt is obviously that the DC power supply of the control circuit loses its source due to the controllable switching from the off state to the on-state operation state, and the DC power supply of the control circuit is lost. The control circuit must consume its own power, and continue to provide the trigger current to the controllable battery. The 6-point voltage will also release the determined power through the controlled and bypassed controllable bypass. This kind of power consumption mode that is only consumed and not supplemented is difficult to maintain. The voltage at 6 o'clock is bound to decrease, which will cause the high-potential output state at the output of the control circuit to generate a certain level of potential drop, and reduce the trigger current supplied to the controllable cell. At 6 o'clock, the voltage continues to drop. When the trigger current provided by the control circuit is small enough, the controllable normal trigger will encounter difficulties.

At this time, the controllable cells that can trigger the current value to be substantially unaffected by the anode voltage will be immediately turned off, so that the bulb will be extinguished due to insufficient controllable trigger current before the circuit delay time comes. Electrical late conduction phenomenon When the pulse DC voltage is at the initial stage of the waveform near zero, the controllable silicon does not conduct. As time goes on, the sinusoidal pulse DC voltage rises to a certain level, and the controllable silicon is turned off. Turned on, its anode voltage drops to near zero. The delay of the controllable turn-on time shortens the power supply time of the bulb, the power is insufficient, and the brightness is reduced. The sinusoidal pulse DC voltage gradually rises and suddenly drops during the controlled period from the turn-off to the conduction period. There is a sharp pulse between BP and d between the anode and cathode of the controllable silicon. This sharp pulse voltage can be supplemented to a certain degree by the anti-spot potential. However, in the initial stage, the peak pulse duration is lower than the peak temperature of the spike. The supplementary effect on the control circuit power supply is not significant, the 6-point potential will continue to drop, so that the trigger current of the control circuit output will be reduced, and the controllable silicon can only progress to delay the conduction time, and the anode voltage will increase after the anode voltage rises. In this way, the duration of the spike of the controllable anode is lengthened, the amplitude is increased, and the conduction range of the controllable baby is narrower, the bulb power supply time is shortened, the electric energy is reduced, and the light progress is darkened. Since the amplitude of the anode tip pulse of the controllable cell is increased during the off period, the power supply supplementing ability of the control circuit is enhanced, and when the above change is performed to a certain extent, the voltage of the spike of the controllable anode can be 0, 1 The supplied electric energy can make up for the current consumption of the control circuit, so that the potential of 6 points does not continue to fall, and the circuit reaches a stable state of relative balance. The controllable state maintains the constant conduction interval for a period of time, so that the bulb is fixed. The lower luminous intensity emits light until the circuit delays from the time when the time comes, and the relevant waveform of the above process is annihilated as shown in Fig. 5. When the lamp is fully lit, the lamp voltage is relatively stable when the lamp starts to dim. The controllable voltage waveform is seen from the above analysis. The phenomenon that the light dimming in the circuit of Figure 4 is caused by insufficient power supply of the control circuit is controllable due to the reduction of the trigger current, delaying the conduction time, shortening the power supply time of the bulb, and supplying power. Insufficient capacity causes the light to dim, not because the controller can act as a load. In fact, when the bulb is normally illuminated, the controllable baby is turned on, but the pressure drop on it is extremely low, and the power loss of the controllable baby is very small. When the bulb changes and the disc is reduced, the Pan Niansheng Pan 4 is completely Yang Zhen sulphur is harsh x. Teng Sheng, but because the controllable baby has not been turned on, no current is passed through, and the controllable insertion does not consume power. However, the darkening of the light is obviously an obvious deficiency of such a circuit. When the amount of the product of this structure is large, the illumination lamp can emit light in the sinusoidal power supply section to cause uneven current distribution, which will cause the power supply waveform to change and affect the power supply quality. , interfere with the normal operation of other electrical appliances.

In addition, due to the dispersion of component parameters, some electronic switches made by this scheme are not obvious in light dimming, and some are more serious, and the quality and performance of the product are not easy to guarantee. Cut, the circuit of Figure 4 should be improved from the inside.

3.2 Solution 3.2.1 Select the controllable baby with more sensitive trigger characteristics, and extend the full conduction time of the controllable discussion, so that the lighting bulb is always in the full voltage supply state during the circuit delay self-twisting time.

3.2.2 Increase the capacitance of the filter capacitor 0 so that it can store more power, delay the decline of the supply voltage of the control circuit, and reduce the darkening of the light to a certain extent. 3.2.3 As shown in Figure 6, the string When the controllable silicon is turned on, the voltage of the heart point drops to near zero. At this time, the diodes in the anti-series are in a reverse bias state, and the controllable insertion of the control circuit through the power supply voltage and conduction is interrupted. The passage of the electric energy is reduced, the consumption of the part is reduced, and the power supply voltage of the control circuit is all used to supply power to the control circuit, which can slow down the downward trend of the DC supply voltage of the control circuit to a certain extent, thereby delaying the reduction or elimination of the light dimming phenomenon. The series-type switching circuit 3.2.4 improves the power supply mode of the control circuit. When the lamp is on and the switch is de-energized, the control circuit can still obtain a sufficient and stable DC power supply. We notice that the controllable silicon is turned on. The sharp pulse voltage between Gd can compensate for the supply voltage loss of the control circuit by moderately, but because of the high resistance value, the attenuation is large, and the degree of compensation is limited. We also notice that the spike The voltage waveform is actually a waveform with a high level of high harmonics. If you can make full use of these higher harmonics and convert them into the DC power required by the control circuit as much as possible, it will achieve good results in various In the circuit component, the capacitive reactance of the capacitor is inversely proportional to the frequency of the voltage across the capacitor. The higher the frequency, the easier the electrical signal passes through the capacitor. Figure 7 is the harmonic rectifier circuit designed according to this design. The pulsed direct current of the heart has relatively low frequency components, and the capacitive reactance is relatively high. The pulse voltage mainly supplies power to the control circuit through anti-buck. After the lamp is on for a short period of time, the voltage of the control circuit drops, and the trigger current decreases, causing the controllable silicon to delay the conduction phenomenon, causing the anode to have a spike, and the high-frequency component of the spike voltage is sent to the point through [2, 5 and After rectification and filtering, it can effectively compensate for the loss of the control circuit supply voltage, so that the 6-point voltage is quickly stabilized at a fixed level, and the circuit can achieve a relative dynamic balance. By adopting this method, the duration of the sharp pulse can be shortened obviously, and the amplitude of the sharp pulse is reduced. The power supply time of the bulb is obviously longer than that of the circuit of FIG. 4, and the light intensity of the light bulb changes. The naked eye has been difficult to detect. The harmonic rectifier type series switching circuit 5 will be controllable. The source of the trigger current is changed to the anode circuit of the controllable baby. The control circuit is changed to output the triggering pilot voltage. The pilot voltage is used to control the triggering current. When the required light is on, the pilot voltage will trigger the current to be introduced into the controllable baby. When the trigger pole needs to be turned off, the delay time will be delayed, and the current bypass control circuit will be triggered to provide the burden of the trigger current. The falling speed of the DC power supply voltage will be significantly slowed down, and the controllable anode has only a duration. Short, lower amplitude spikes, auxiliary 1 shown in Figure 7 harmonic rectifier circuit, the DC supply voltage of the control circuit will be more adequate and stable, the bulb is close to full voltage working state, basically keep the brightness is not 4 The problem of insufficient power supply for the load is the key to the development of the electronic indoor lighting switch. From the above analysis, the electronic lighting switch supplies insufficient power to the load, or Due to the insufficient trigger current, the two-way controllable single-pass is turned on, or the control current is narrowed due to the decrease of the trigger current. The load supply waveforms all have obvious changes to the outdoor common-time delay switch. The white light is used as the load, and the effect on the load is only light and dark.

You Erhua 6836, corpse 7, and two 0.0017 weeks Taiming. Principle and design of light source, Shanghai: Fudan University Press, 1993 Automotive Lighting, Shanghai Lighting Engineering Research also edited Zhang Zhiying and the indoor switch is different. The load here may be white light or ordinary magnetic ballast. Floodlights, capacitive ballast fluorescent lamps with capacitance compensation, high power factor inductive ballast fluorescent lamps or electronic ballast fluorescent lamps. The two-way controllable one-way conduction will make the inductive ballast fluorescent lamp unable to start due to DC power supply. The conduction interval of the controllable DC is obviously narrowed, which will cause the sudden change from zero to the front of the higher voltage at the beginning of the pulse voltage. Such a large voltage change rate will cause a capacitively compensated inductive ballast fluorescent lamp, an electronic ballast fluorescent lamp, etc., to generate a strong spike-like inrush current at the initial stage of each power supply cycle, which will not only Increasing the harmonics of the current reduces the line power factor and is also highly susceptible to damage to the electronic ballast. The cut, the output voltage is insufficient, and the influence of the indoor electronic switch is greater. Because the illumination duration of the indoor lighting is much longer than that of the outdoor lighting, the requirement of the DC power supply voltage of the indoor electronic control circuit is more demanding. 1], the problem of insufficient output voltage is difficult to avoid, and the practical use of electronic indoor lighting switch is impossible to talk about. This is the design difficulty of electronic indoor lighting switch.