CN216752163U - Phase-cut dimming circuit and dimmer - Google Patents
Phase-cut dimming circuit and dimmer Download PDFInfo
- Publication number
- CN216752163U CN216752163U CN202123247885.XU CN202123247885U CN216752163U CN 216752163 U CN216752163 U CN 216752163U CN 202123247885 U CN202123247885 U CN 202123247885U CN 216752163 U CN216752163 U CN 216752163U
- Authority
- CN
- China
- Prior art keywords
- controllable silicon
- bidirectional
- current
- control circuit
- bidirectional controllable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Circuit Arrangement For Electric Light Sources In General (AREA)
Abstract
The utility model relates to a phase cut dimmer circuit and light modulator belongs to the dimmer circuit field, and this circuit is used for establishing ties between light source load circuit and alternating current power supply, and it includes: the first bidirectional controllable silicon, the second bidirectional controllable silicon and the bidirectional controllable silicon control circuit; the first bidirectional controllable silicon and the second bidirectional controllable silicon are connected in parallel, the first end of the bidirectional controllable silicon control circuit is connected with the control electrode of the first bidirectional controllable silicon, and the second end of the bidirectional controllable silicon control circuit is connected with the control electrode of the second bidirectional controllable silicon; the maintaining current of the first bidirectional controllable silicon is larger than that of the second bidirectional controllable silicon, the maintaining current of the first bidirectional controllable silicon is smaller than or equal to the on-state current effective value of the second bidirectional controllable silicon, and the bidirectional controllable silicon control circuit is used for receiving a light adjusting gear instruction and controlling at least one of the first bidirectional controllable silicon and the second bidirectional controllable silicon to be conducted according to the light adjusting gear instruction; the utility model provides a problem that scintillation appears in the light source load in the light modulation process.
Description
Technical Field
The utility model relates to a dimming circuit field, in particular to phase-cut dimming circuit and light modulator.
Background
With the development of science and technology and the improvement of the living standard of people, the phase-cut dimming technology is more and more widely applied in life. The front edge or the back edge phase cutting is carried out on the sine wave voltage through the bidirectional silicon controlled rectifier or the MOS tube, so that the effective value of the sine wave voltage is changed, and the aim of dimming is fulfilled. With the development of LED technology, LED light rate is greatly improved, and many scenes using LED lamps of less than 5W are enough to meet lighting requirements. At present, the rated power of a phase-cut dimmer is above 300W, a bidirectional thyristor with a large on-state current effective value and a large non-repetitive surge peak conduction current value is selected, the dimming flicker problem can occur when the light source load is dimmed to low brightness, and the problem that the compatibility of an LED lamp with the power less than 5W is extremely poor, and even the dimming cannot occur.
In summary, a highly-compatible phase-cut dimming circuit is needed to solve the above problems, so as to meet the dimming lighting requirements of more scenes.
SUMMERY OF THE UTILITY MODEL
In order to solve the technical problem, the utility model provides a phase-cut dimming circuit and light modulator.
The utility model discloses a following technical scheme realizes:
on the one hand, the embodiment of the utility model provides a phase cut dimmer circuit for establish ties between light source load circuit and alternating current power supply, it includes: the first bidirectional controllable silicon, the second bidirectional controllable silicon and the bidirectional controllable silicon control circuit;
the first bidirectional controllable silicon and the second bidirectional controllable silicon are connected in parallel, a T1 pole of the first bidirectional controllable silicon and a T1 pole of the second bidirectional controllable silicon are both connected with a first input power end of an alternating current power supply, and a T2 pole of the first bidirectional controllable silicon and a T2 pole of the second bidirectional controllable silicon are both connected with a second input power end of the alternating current power supply through a light source load;
the first end of the bidirectional controllable silicon control circuit is connected with the control electrode of the first bidirectional controllable silicon, and the second end of the bidirectional controllable silicon control circuit is connected with the control electrode of the second bidirectional controllable silicon;
the holding current of the first bidirectional controllable silicon is a first current I1, the holding current of the second bidirectional controllable silicon is a second current I2, the effective value of the on-state current of the second bidirectional controllable silicon is a third current I3, the first current I1 is larger than the second current I2, and the first current I1 is smaller than or equal to the third current I3;
the bidirectional controlled silicon control circuit is used for receiving a dimming gear instruction and controlling at least one of the first bidirectional controlled silicon and the second bidirectional controlled silicon to be conducted according to the dimming gear instruction.
In one embodiment, when the dimming range corresponding to the dimming range command is in the first range, the triac control circuit controls the second triac to be turned on to dim the light source load, and the effective value of the current flowing through the light source load is greater than or equal to the second current I2 and smaller than the first current I1; when the dimming gear corresponding to the dimming gear instruction is in the second gear range, the bidirectional controlled silicon control circuit controls the first bidirectional controlled silicon to be conducted to dim the light source load and controls the second bidirectional controlled silicon to be turned off, and the effective value of the current flowing through the light source load is larger than the third current I3.
In one embodiment, the phase-cut dimming circuit further comprises an overcurrent protection device;
the overcurrent protection device and the second bidirectional controllable silicon form a series circuit, and the series circuit is connected with the first bidirectional controllable silicon in parallel;
when the current flowing through the overcurrent protection device is larger than the preset current value, the overcurrent protection device is disconnected, and then the second bidirectional controllable silicon is disconnected.
In one embodiment, the bidirectional thyristor control circuit comprises a potentiometer RP, a resistor R1, a capacitor C1, a bidirectional trigger diode KS1, and a bidirectional trigger diode KS 2;
potentiometer RP, resistance R1 and electric capacity C1 are series connection in proper order, and the first end and the second end setting of bidirectional thyristor control circuit are in resistance R1 with between the electric capacity C1, bidirectional thyristor control circuit's first end passes through diac KS1 and links to each other with first bidirectional thyristor's control pole, and bidirectional thyristor control circuit's second end passes through diac KS2 and links to each other with the control pole of second bidirectional thyristor.
In one embodiment, the phase-cut dimming circuit further comprises a current detection device;
the current detection device is used for detecting the current value of the load flowing through the light source and transmitting the current value to the bidirectional controllable silicon control circuit.
In one embodiment, the triac control circuit comprises an MCU;
the first end of the MCU is connected with the control electrode of the first bidirectional controllable silicon to control the turn-off or turn-on of the first bidirectional controllable silicon; the second end of the MCU is connected with the control electrode of the second bidirectional controllable silicon to control the on/off of the second bidirectional controllable silicon.
On the other hand, the embodiment of the utility model provides a dimmer, this dimmer have the phase cut dimmer circuit in the preceding to be provided with first fender position interval and second fender position interval.
The utility model provides a cut looks dimmer circuit and light modulator has the high compatible function of adjusting luminance of cutting looks, the light source load of compatible low-power light source load compatible high power again promptly. Compared with the prior art, the beneficial effects of the utility model are that: based on the dimming characteristic of the bidirectional thyristors, the bidirectional thyristors of more than two specific models are selected to be connected in parallel, and the bidirectional thyristor control circuit is designed to control the conduction of the first bidirectional thyristor or the second bidirectional thyristor according to the dimming gear instruction to dim the light of the light source load, so that the phase-cut dimming range is widened, and the bidirectional thyristor control circuit is suitable for low-power or low-brightness light source loads without flickering or unlighting of the light source load.
Drawings
FIG. 1 is a schematic block diagram of a common phase-cut dimming circuit;
fig. 2 is a schematic block diagram of a phase-cut dimming circuit according to the present invention;
FIG. 3 is a block diagram of the triac control circuit used in conjunction with a current sensing device in an embodiment;
FIG. 4 is a block diagram of the embodiment in which the triac control circuit is used in conjunction with an overcurrent protection device;
FIG. 5 is a block diagram of the combination of a potentiometer and a capacitor in an embodiment;
FIG. 6 is a block diagram of the MCU and the overcurrent protection device used in combination in the embodiment;
FIG. 7 is a block diagram of the triac control circuit, current sensing device and overcurrent protection device used in conjunction with one embodiment;
fig. 8 is a schematic diagram of two on-off states of the triac according to the embodiment of the present invention.
The reference numerals are illustrated below:
AC-AC power supply, L-phase line, N-neutral line.
Detailed Description
In order to make the technical solutions of the present invention better understood by those skilled in the art, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiment of the present invention, other schemes obtained by a person of ordinary skill in the art without creative work should belong to the protection scope of the present invention.
The bidirectional thyristor is developed on the basis of common thyristors, can replace two thyristors with reversed polarities connected in parallel, only needs one trigger circuit, and is an ideal alternating current switching device. The triac has two main electrodes T1 and T2 and a gate G which enables the device to be triggered in both the forward and reverse directions of the main electrodes. The parameters commonly used for the bidirectional thyristor are as follows: an on-state current effective value IT (RMS), a non-repetitive surge peak on current ITSM, a latching current IL, a holding current IH, and a gate trigger current IGT. Generally, the larger the IT (RMS), the larger the IL and IH will be. In order to turn on the triac, the gate current must be greater than or equal to IGT until the load current reaches greater than or equal to IL. The turn-off condition of the triac is load current < IH. When the capacitive load is used, the peak current can reach more than 100 times of the effective current when the peak or the trough of the sine wave is input to perform phase cutting. In order to obtain a large capacity rated power, the existing dimmer must select a triac with large it (rms) and ITSM, but dimming compatibility to a low-power load is very poor, or a lamp flash phenomenon occurs when the load is at low brightness.
Example 1
Fig. 1 shows a schematic block diagram of a general phase-cut dimming circuit. The circuit includes: light source load, triac. The triac adopts a large current (IH value is large) triac to adjust light, and when the light source load is low power or low brightness, the current flowing through the light source load is smaller than the holding current IL and the holding current IH of the triac, so that the triac cannot be normally conducted, and the light source load flickers or cannot be lightened.
Fig. 2 shows a schematic block diagram of the phase-cut dimming circuit of the present invention. According to fig. 2, the phase-cut dimming circuit is connected in series between a light source load circuit and an ac power source, and includes: the bidirectional thyristor control circuit comprises a first bidirectional thyristor BCR1, a second bidirectional thyristor BCR2 and a bidirectional thyristor control circuit;
the first bidirectional thyristor BCR1 and the second bidirectional thyristor BCR2 are connected in parallel, a T1 pole of the first bidirectional thyristor BCR1 and a T1 pole of the second bidirectional thyristor BCR2 are both connected with a first input power supply end of the alternating current power supply, and a T2 pole of the first bidirectional thyristor BCR1 and a T2 pole of the second bidirectional thyristor BCR2 are both connected with a second input power supply end of the alternating current power supply through a light source load;
the first end of the bidirectional thyristor control circuit is connected with the control electrode of the first bidirectional thyristor BCR1, and the second end of the bidirectional thyristor control circuit is connected with the control electrode of the second bidirectional thyristor BCR 2;
in the phase-cut dimming circuit of this embodiment, two specific types of first triac BCR1 and second triac BCR2 may be selected to be connected in parallel, where the holding current of the first triac BCR1 is a first current I1, the holding current of the second triac BCR2 is a second current I2, the effective value of the on-state current is a third current I3, the non-repetitive surge peak value conduction current ITSM is a fourth current I4, the first current I1 is greater than the second current I2, the first current I1 is less than or equal to the fourth current I4, preferably, the first current I1 is greater than the second current I2, the first current I1 is less than or equal to the third current I3, in other embodiments, a person skilled in the art may connect three or more triacs in parallel step by step according to the above principle according to the actual situation, to implement finer adjustment, switch step by step, and make a full-step seamless gear, and avoid that two thyristors connected in parallel and having too large span do not satisfy the above condition, the situation may occur where I1 is greater than not only I2 but also I3, thereby burning the second triac when switched by the first triac because the load current is greater than I3.
The bidirectional thyristor control circuit is provided with a dimming gear for receiving a dimming gear instruction, the dimming gear is divided into two gear intervals, namely a first gear interval and a second gear interval, for example, the gear with the dimming brightness value of 30% -100% is the second gear interval, the gear with the brightness value of less than 30% and more than 0% is the first gear interval, and the skilled person knows that the gear intervals in different ranges or more gear intervals can be set according to the number and the selection of the bidirectional thyristors. The triac control circuit is capable of controlling at least one of the first triac BCR1 and the second triac BCR2 to conduct in accordance with the dimming gear command. When the bidirectional controllable silicon control circuit receives a brighter dimming gear instruction, and the dimming gear corresponding to the dimming gear instruction is in a second gear range, the bidirectional controllable silicon control circuit controls the first bidirectional controllable silicon BCR1 to be conducted to dim the light source load, at the moment, the effective value of the current flowing through the light source load is larger than or equal to the first current I1 and larger than the third current I3, and the bidirectional controllable silicon control circuit controls the second bidirectional controllable silicon BCR2 to be turned off so as to avoid the second bidirectional controllable silicon BCR2 from being broken down by large current; when the light source load is dimmed, and the dimming gear instruction received by the bidirectional controllable silicon control circuit is in a first gear range, the effective value of the current flowing through the light source load is greater than or equal to a second current I2 and is less than a first current I1, the first bidirectional controllable silicon BCR1 is turned off at a zero crossing point, the light source load flickers, and the bidirectional controllable silicon control circuit controls the second bidirectional controllable silicon BCR2 to be turned on to dim the light source load so as to avoid the phenomenon that the light source load flickers.
In the dimming process, the phase-cut dimming circuit can be seamlessly connected and can switch and conduct the first bidirectional controllable silicon or the second bidirectional controllable silicon back and forth to dim the light source load, the light source load cannot flicker, the phase-cut dimming range of the phase-cut dimming circuit is widened, and the phase-cut dimming circuit is suitable for the light source load with low power or low brightness, and cannot flicker or be lightened.
The bidirectional thyristor control circuit preferably controls the bidirectional thyristor by the MCU, and the first end of the MCU is connected with the control electrode of the first bidirectional thyristor BCR1 to control the turn-off or turn-on of the first bidirectional thyristor BCR 1; the second end of the MCU is connected with the control electrode of the second bidirectional thyristor BCR2, and the second bidirectional thyristor BCR2 is controlled to be turned off or turned on. MCU has multiple types such as 4 MCU, 8 MCU, 16 MCU, 32 MCU, preferably, uses 4 MCU, and 4 MCU low power consumptions, interference immunity are strong, simple structure, stability are good, let phase cut dimmer circuit stability strong, can adapt to complicated application environment, long service life. According to the method, programs corresponding to the first gear range and the second gear range are set in the MCU. When the MCU receives a dimming gear command, if the dimming gear corresponding to the dimming gear command is in the second gear range, the MCU controls the first triac BCR1 to be turned on to dim the light source load, and controls the second triac BCR2 to be turned off, and if the dimming gear corresponding to the dimming gear command is in the first gear range, the MCU controls the second triac BCR2 to be turned on to dim the light source load, and controls the first triac BCR1 to be turned off. Because the MCU sets the gear interval and judges which gear interval the dimming gear instruction is positioned in, the precision is high, and the reaction speed is high, the bidirectional thyristor control circuit can more accurately control the brightness of the light source load by selecting the MCU.
Example 2
Fig. 3 is a block diagram showing the triac control circuit and the current check device in the present embodiment, and according to fig. 3, on the basis of embodiment 1, the tangential dimming circuit is additionally provided with the current check device, that is, the phase-cut dimming circuit includes: the device comprises a first bidirectional thyristor BCR1, a second bidirectional thyristor BCR2, a current checking device and a bidirectional thyristor control circuit;
the first end of the bidirectional thyristor control circuit is connected with the control electrode of the first bidirectional thyristor BCR1, and the second end of the bidirectional thyristor control circuit is connected with the control electrode of the second bidirectional thyristor BCR 2;
the current detection device is used for detecting the current value of the load flowing through the light source and transmitting the current value to the bidirectional controllable silicon control circuit.
The bidirectional controllable silicon control circuit is used for receiving a dimming gear instruction and outputting a control signal according to the dimming gear instruction to control at least one of the first bidirectional controllable silicon BCR1 and the second bidirectional controllable silicon BCR2 to be conducted, namely, the light source load is dimmed and the brightness of the light source load is adjusted by adjusting the conduction angles of the first bidirectional controllable silicon BCR1 and the second bidirectional controllable silicon BCR 2.
In this embodiment, a gear range may be added on the basis of embodiment 1, the gear of the triac control circuit is divided into three gear ranges, that is, a first gear range, a second gear range, and a third gear range, when the triac control circuit receives a dimming gear command, and the gear corresponding to the dimming gear command is in the third gear range, in each ac half cycle, the current detection device detects a current value flowing through the light source load, and transmits the current value to the triac control circuit, the triac control circuit controls the first triac BCR1 to be turned on when the current value is equal to or greater than a holding current of the first triac, and adjusts the light source load, and the triac control circuit controls the second triac BCR2 to be turned on when the current value is equal to an effective value of an on-state current of the second triac BCR2 for the second time, dimming a light source load; when the light source load is dimmed again, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional controllable silicon control circuit is in a second gear range, the bidirectional controllable silicon control circuit controls the first bidirectional controllable silicon BCR1 to be conducted to dim the light source load, at the moment, the current flowing through the light source load is larger than the on-state current effective value of the second bidirectional controllable silicon BCR2, and the bidirectional controllable silicon control circuit controls the second bidirectional controllable silicon BCR2 to be switched off so as to avoid the light source load from being broken down by large current; when the light source load is further dimmed, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional thyristor control circuit is in a first gear range, the current flowing through the light source load is smaller than the maintaining current of the first bidirectional thyristor BCR1, the first bidirectional thyristor BCR1 is turned off at the zero crossing point, the light source load is about to flicker, and at the moment, the bidirectional thyristor control circuit controls the second bidirectional thyristor BCR2 to be turned on, so that the light source load is dimmed, and the phenomenon that the light source load flickers is avoided.
In this embodiment, on the basis of embodiment 1, the current inspection device is additionally provided, so that conduction of the triac can be controlled more accurately, the triac is protected better, one more gear interval can be set, the phase-cut dimming range of the phase-cut dimming circuit is further widened, and the circuit is suitable for a low-power or low-brightness light source load without flickering or unlighting of the light source load.
The bidirectional thyristor control circuit is preferably an MCU, and the first end of the MCU is connected with the control electrode of the first bidirectional thyristor BCR1 to control the on/off of the first bidirectional thyristor BCR 1; the second end of the MCU is connected with the control electrode of the second bidirectional thyristor BCR2, and the second bidirectional thyristor BCR2 is controlled to be turned off or turned on. Because the MCU sets the gear interval and judges which gear interval the dimming gear instruction is positioned in, the precision is high, and the reaction speed is high, the bidirectional thyristor control circuit can more accurately control the brightness of the light source load by selecting the MCU.
Example 3
Fig. 4 is a block diagram showing the bidirectional thyristor control circuit and the overcurrent protection device in cooperation, according to fig. 4, on the basis of embodiment 1, the tangential dimming circuit is additionally provided with the overcurrent protection device, that is, the phase-cut dimming circuit includes: the device comprises a first bidirectional thyristor BCR1, a second bidirectional thyristor BCR2, an overcurrent protection device and a bidirectional thyristor control circuit;
the overcurrent protection device and the second bidirectional thyristor BCR2 form a series circuit, and the series circuit is connected with the first bidirectional thyristor BCR1 in parallel;
the first end of the bidirectional thyristor control circuit is connected with the control electrode of the first bidirectional thyristor BCR1, and the second end of the bidirectional thyristor control circuit is connected with the control electrode of the second bidirectional thyristor BCR 2;
the bidirectional controlled silicon control circuit is used for receiving a dimming gear instruction and outputting a control signal according to the dimming gear instruction to control at least one of the first bidirectional controlled silicon BCR1 and the second bidirectional controlled silicon BCR2 to be conducted, namely, the light source load is dimmed by adjusting the conduction angles of the first bidirectional controlled silicon BCR1 and the second bidirectional controlled silicon BCR2, and the brightness of the light source load is adjusted.
In the dimming process, when the current flowing through the over-current protection device is larger than a preset current value, the over-current protection device is switched off, and the second bidirectional thyristor BCR2 is further controlled to be switched off, wherein the preset current value is set to be larger than or equal to the on-state current effective value of the second bidirectional thyristor BCR2 but smaller than the non-repetitive surge peak conduction current ITSM of the second bidirectional thyristor BCR 2.
The overcurrent protection device can select a circuit breaker or a relay, preferably the relay which has high reaction speed and can control the on and off of the overcurrent protection device according to the magnitude of current flowing through the overcurrent protection device more accurately, and further more accurately control the on and off of the second bidirectional thyristor BCR 2.
In this embodiment, 2 gear intervals can be added on the basis of embodiment 1, the gear of the triac control circuit is divided into four gear intervals, namely, a first gear interval, a second gear interval, a third gear interval and a fourth gear interval, when the triac control circuit receives a dimming gear instruction, and the dimming gear corresponding to the dimming gear instruction is in the fourth gear interval, in each ac half cycle, the triac control circuit first controls the second triac BCR2 to be turned on to dim the light source load, when the current flowing through the overcurrent protection device is greater than a preset current value, the overcurrent protection device is turned off, and further controls the second triac BCR2 to be turned off, at this time, the triac control circuit controls the first triac BCR1 to be turned on to dim the light source load, when the current reaches the maximum value and falls back to the overcurrent protection device to be turned on, the second bidirectional controllable silicon BCR2 is controlled to be conducted again to dim the light source load; when the light source load is dimmed, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional thyristor control circuit is in a third gear range, the bidirectional thyristor control circuit firstly controls the first bidirectional thyristor BCR1 to be conducted to dim the light source load in each alternating current half cycle, and when the current reaches the maximum value and falls back to the overcurrent protection device to be conducted, the bidirectional thyristor control circuit controls the second bidirectional thyristor BCR2 to be conducted to dim the light source load; when the light source load is dimmed again, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional controllable silicon control circuit is in a second gear range, the bidirectional controllable silicon control circuit controls the first bidirectional controllable silicon BCR1 to be conducted, so that the light source load is dimmed; when the light source load is further dimmed, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional thyristor control circuit is in a first gear range, the current flowing through the light source load is smaller than the maintaining current of the first bidirectional thyristor BCR1, the first bidirectional thyristor BCR1 is turned off at the zero crossing point, the light source load flickers, and at the moment, the bidirectional thyristor control circuit controls the second bidirectional thyristor BCR2 to be turned on to dim the light source load, so that the phenomenon that the light source load flickers is avoided.
In this embodiment, on the basis of embodiment 1, the overcurrent protection device is additionally provided to better protect the triac, two more gear intervals can be set, and the phase-cut dimming range of the phase-cut dimming circuit is further widened.
As shown in fig. 5, the triac control circuit of this embodiment optionally includes a potentiometer RP, a resistor R1, and a capacitor C1 connected in series in this order, a first end and a second end of the triac control circuit are disposed between the resistor R1 and the capacitor C1, the first end of the triac control circuit is connected to the control electrode of the first triac BCR1 through a diac KS1, the second end of the triac control circuit is connected to the control electrode of the second triac BCR2 through the diac KS2, the overcurrent protection device controls the turn-off and turn-on of the second triac BCR2 according to the magnitude of the current flowing through the overcurrent protection device, adjusts the charging and discharging speed of the capacitor C1 and selects the capacitor C1 of a specific model and the diac of a specific model, adjusts the conduction angles of the first triac BCR1 and the second triac BCR2 through the potentiometer RP, thereby dimming the light source load. The circuit design has the advantages of simple structure, convenient operation, low cost, long service life and good market prospect.
As shown in fig. 6, the triac control circuit of this embodiment optionally includes an MCU, a first end of the MCU is connected to a control electrode of the first triac BCR1, and the first triac BCR1 is controlled to be turned off or turned on; the second end of the MCU is connected with the control electrode of the second bidirectional thyristor BCR2, and the second bidirectional thyristor BCR2 is controlled to be turned off or turned on. The MCU receives a dimming gear instruction and outputs a control signal to adjust the conduction angles of the first bidirectional controllable silicon BCR1 and the second bidirectional controllable silicon BCR2 to dim the light of the light source load, and in the dimming process, when the current flowing through the over-current protection device is larger than a preset current value, the over-current protection device is disconnected, so that the second bidirectional controllable silicon BCR2 is controlled to be disconnected; when the current flowing through the overcurrent protection device is smaller than or equal to a preset current value, the overcurrent protection device is switched on, and then the second bidirectional thyristor BCR2 is controlled to be switched on. The design of the circuit has the advantages of simple operation, high reaction speed, friendly user operation interface and the like.
Example 4
Fig. 7 is a block diagram showing the bidirectional thyristor control circuit, the current detection device and the overcurrent protection device in cooperation, and according to fig. 7, on the basis of the above embodiment, the phase-cut dimming circuit includes: the device comprises a first bidirectional thyristor BCR1, a second bidirectional thyristor BCR2, a current checking device, an overcurrent protection device and a bidirectional thyristor control circuit;
the overcurrent protection device and the second bidirectional thyristor BCR2 form a series circuit, and the series circuit is connected with the first bidirectional thyristor BCR1 in parallel;
when the current flowing through the overcurrent protection device is larger than the preset current value, the overcurrent protection device is disconnected, and then the second bidirectional thyristor BCR2 is disconnected.
The overcurrent protection device can select a circuit breaker or a relay, preferably the relay, the relay has high reaction speed, and the on-off of the relay can be controlled more accurately according to the magnitude of current flowing through the relay, so that the on-off and the on-off of the second bidirectional controllable silicon are controlled more accurately.
The current detection device is used for detecting the current value of the load flowing through the light source and transmitting the current value to the bidirectional controllable silicon control circuit.
In this embodiment, the shift of the triac control circuit is divided into four shift ranges, namely a first shift range, a second shift range, a third shift range and a fourth shift range, when the triac control circuit receives a dimming shift command, and the dimming shift corresponding to the dimming shift command is in the fourth shift range, in each ac half cycle, when the current value of the light source load detected by the current detection device is equal to the holding current of the second triac BCR2, the triac control circuit controls the second triac BCR2 to be turned on to dim the light source load, and when the current value of the current flowing through the overcurrent protection device is equal to or greater than a preset current value, the overcurrent protection device is turned off to further control the second triac BCR2 to be turned off, and at this time, the triac control circuit controls the first triac BCR1 to be turned on to dim the light source load, when the current reaches the maximum value and falls back to the overcurrent protection device to be switched on, the second bidirectional controllable silicon BCR2 is controlled to be switched on again to dim the light source load; when the light source load is dimmed, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional controllable silicon control circuit is in a third gear range, in each alternating current half cycle, when the current detection device detects that the current value flowing through the light source load is greater than or equal to the holding current of the first bidirectional controllable silicon BCR1, the bidirectional controllable silicon control circuit firstly controls the first bidirectional controllable silicon BCR1 to be conducted to dim the light source load, and when the current reaches the maximum value and falls back to the overcurrent protection device to be conducted, the bidirectional controllable silicon BCR2 is controlled to be conducted to dim the light source load; when the light source load is dimmed again, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional controllable silicon control circuit is in a second gear range, the bidirectional controllable silicon control circuit controls the first bidirectional controllable silicon BCR1 to be conducted, so that the light source load is dimmed; when the light source load is further dimmed, and the dimming gear corresponding to the dimming gear instruction received by the bidirectional controllable silicon control circuit is in the first gear range, the current flowing through the light source load is smaller than the maintaining current of the first bidirectional controllable silicon BCR1, the first bidirectional controllable silicon BCR1 cannot be conducted, the light source load is about to flicker, and at the moment, the bidirectional controllable silicon control circuit controls the second bidirectional controllable silicon BCR2 to be conducted, so that the light source load is dimmed, and the phenomenon that the light source load flickers is avoided.
This embodiment has add current detection device on embodiment 1's basis, overcurrent protection device, can seamless, the mutual switch switches on bidirectional thyristor, adjust luminance light source load, and bidirectional thyristor has been protected better, can set up four fender position intervals, phase cut dimming range of phase cut dimming circuit has further been widened, detect the electric current often through current detection device, and transmit this current value for bidirectional thyristor control circuit, more accurately control bidirectional thyristor switches on, keep off position operating command more accurate, have higher compatibility, the scintillation of light source load in the in-process of adjusting luminance has been avoided.
Preferably, the triac control circuit comprises an MCU, and a maintaining current value of the first triac BCR1, a maintaining current value of the second triac BCR2 and a preset current value of the overcurrent protection device are preset in the MCU. The MCU adjusts the conduction angle of the first bidirectional controllable silicon BCR1 or the second bidirectional controllable silicon BCR2 according to the preset value of the MCU, adjusts the light source load, and has the advantages of high reaction speed, good expansibility and the like.
The MCU receives a dimming gear instruction, when the brightness of the light source load is adjusted downwards, the effective value of current flowing through the light source load is gradually reduced, the current flowing through the first bidirectional thyristor BCR1 and the second bidirectional thyristor BCR2 which are connected in parallel is synchronously reduced, and when the current is smaller than the maintaining current of the first bidirectional thyristor BCR1, the MCU controls the second bidirectional thyristor BCR2 to be conducted according to the current value detected by the received current detection device, so that the light source load is dimmed; when the current flowing through the light source load is gradually increased, the current flowing through the first bidirectional thyristor BCR1 and the second bidirectional thyristor BCR2 which are connected in parallel is synchronously increased, and the current is larger than the effective value of the on-state current of the second bidirectional thyristor BCR2, in order to protect the second bidirectional thyristor BCR2 from being broken down by large current, the overcurrent protection device is disconnected, and further the second bidirectional thyristor BCR2 is controlled to be disconnected, and the MCU controls the first bidirectional thyristor BCR1 to be connected according to the current value detected by the received current detection device, so that the light source load is dimmed. According to the change of the current value flowing through the light source load, the first bidirectional controllable silicon BCR1 and the second bidirectional controllable silicon BCR2 which are connected in parallel are in seamless connection and switched on with each other accurately, the light source load is adjusted in light, the light adjusting range is widened, high compatibility is achieved, and the phenomenon that the light source load flickers in the light adjusting process is avoided.
Fig. 8 shows that when the dimming range command is in the fourth range, in the dimming process, the on state (on state) and the off state (off state) of each time period of the first triac BCR1 (large thyristor) and the second triac BCR2 (small thyristor) are seamlessly connected and switched back and forth to conduct the first triac BCR1 or the second triac BCR2 to dim the light source load.
Example 5
The phase-cut dimming circuit can be used for manufacturing a dimmer, the dimmer is provided with a first gear range and a second gear range, and dimming can be performed on light source loads with low power and high power or light sources with low brightness and high brightness without flickering or non-lighting of the light source loads. The dimmer has high compatibility and low cost, and can meet the multi-environment illumination requirement.
The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be equivalent replacement modes, and all are included in the scope of the present invention.
Claims (8)
1. A phase-cut dimming circuit for series connection between a light source load circuit and an ac power source, comprising: the first bidirectional controllable silicon, the second bidirectional controllable silicon and the bidirectional controllable silicon control circuit;
the first bidirectional thyristor and the second bidirectional thyristor are connected in parallel, a T1 pole of the first bidirectional thyristor and a T1 pole of the second bidirectional thyristor are both connected with a first input power end of an alternating current power supply, and a T2 pole of the first bidirectional thyristor and a T2 pole of the second bidirectional thyristor are both connected with a second input power end of the alternating current power supply through a light source load;
the first end of the bidirectional controllable silicon control circuit is connected with the control electrode of the first bidirectional controllable silicon, and the second end of the bidirectional controllable silicon control circuit is connected with the control electrode of the second bidirectional controllable silicon;
the maintaining current of the first bidirectional thyristor is a first current I1, the maintaining current of the second bidirectional thyristor is a second current I2, the effective value of the on-state current of the second bidirectional thyristor is a third current I3, the first current I1 is greater than the second current I2, and the first current I1 is less than or equal to the third current I3;
the bidirectional controllable silicon control circuit is used for receiving a dimming gear instruction and controlling at least one of the first bidirectional controllable silicon and the second bidirectional controllable silicon to be conducted according to the dimming gear instruction.
2. The phase-cut dimming circuit of claim 1, wherein when the dimming range corresponding to the dimming range command is in a first range, the triac control circuit controls the second triac to conduct to dim the light source load, and the effective value of the current flowing through the light source load is greater than or equal to the second current I2 and less than the first current I1; when the dimming gear corresponding to the dimming gear instruction is located in the second gear interval, the bidirectional thyristor control circuit controls the first bidirectional thyristor to conduct to dim the light source load and control the second bidirectional thyristor to be turned off, and the effective value of the current flowing through the light source load is greater than the third current I3.
3. The phase-cut dimming circuit of claim 1, further comprising an overcurrent protection device;
the overcurrent protection device and the second bidirectional controllable silicon form a series circuit, and the series circuit is connected with the first bidirectional controllable silicon in parallel;
when the current flowing through the overcurrent protection device is larger than a preset current value, the overcurrent protection device is switched off, and then the second bidirectional controllable silicon is switched off.
4. The phase-cut dimming circuit of claim 1, wherein the triac control circuit comprises a potentiometer RP, a resistor R1, a capacitor C1, a diac KS1, a diac KS 2;
the potentiometre RP resistance R1 with electric capacity C1 is series connection in proper order, bidirectional thyristor control circuit's first end and second end set up resistance R1 with between the electric capacity C1, bidirectional thyristor control circuit's first end pass through diac KS1 with the control pole of first bidirectional thyristor links to each other, bidirectional thyristor control circuit's second end pass through diac KS2 with the control pole of second bidirectional thyristor links to each other.
5. The phase-cut dimming circuit of claim 1, further comprising a current detection device;
the current detection device is used for detecting the current value of the load flowing through the light source and transmitting the current value to the bidirectional controllable silicon control circuit.
6. The phase-cut dimming circuit of claim 2, further comprising a current detection device;
the current detection device is used for detecting the current value of the load flowing through the light source and transmitting the current value to the bidirectional controllable silicon control circuit.
7. The phase-cut dimming circuit of any one of claims 1, 2, 3, 5 or 6, wherein the triac control circuit comprises an MCU;
the first end of the MCU is connected with the control electrode of the first bidirectional controllable silicon to control the turn-off or turn-on of the first bidirectional controllable silicon; and the second end of the MCU is connected with the control electrode of the second bidirectional controllable silicon to control the turn-off or the turn-on of the second bidirectional controllable silicon.
8. A dimmer having a phase-cut dimmer circuit as claimed in any one of claims 1 to 7, said dimmer being provided with a first range and a second range.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123247885.XU CN216752163U (en) | 2021-12-22 | 2021-12-22 | Phase-cut dimming circuit and dimmer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123247885.XU CN216752163U (en) | 2021-12-22 | 2021-12-22 | Phase-cut dimming circuit and dimmer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216752163U true CN216752163U (en) | 2022-06-14 |
Family
ID=81936979
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202123247885.XU Active CN216752163U (en) | 2021-12-22 | 2021-12-22 | Phase-cut dimming circuit and dimmer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216752163U (en) |
-
2021
- 2021-12-22 CN CN202123247885.XU patent/CN216752163U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1498055B (en) | Light modulation control system for electronic ballast | |
| CN108141946B (en) | Load control device for high efficiency loads | |
| CN102378450B (en) | Led driver circuit and led lighting device using the same | |
| CA2573767C (en) | Programmable wallbox dimmer | |
| CN201937885U (en) | Three-line dimmer | |
| WO2013108331A1 (en) | Two-line dimmer switch | |
| AU2016200365B2 (en) | Control apparatus using variations in conduction angle as control command | |
| US8493002B2 (en) | Driver for cooperating with a wall dimmer | |
| CN103957636A (en) | Two-wire dimming circuit | |
| EP4203616B1 (en) | Load control device having an overcurrent protection circuit | |
| KR20120082912A (en) | Dimmable lighting system | |
| CN103975650A (en) | Systems and methods of led dimmer compatibility | |
| CN102404907B (en) | Three-wire dimmer | |
| CN102573213A (en) | LED (Light Emitting Diode) dimming system | |
| WO2011060728A1 (en) | Method and apparatus for controlling brightness of light emitting diodes | |
| CN103068102A (en) | AC LED device capable of continuously dimming | |
| US11388803B2 (en) | Triac dimming system for lighting dimming function | |
| CN216752163U (en) | Phase-cut dimming circuit and dimmer | |
| CN211580266U (en) | Phase-cut dimming circuit | |
| CN101790271A (en) | Light controller capable of regulating delay and brightness | |
| CN204069410U (en) | Two-wire system light adjusting circuit | |
| CN212163763U (en) | Silicon controlled rectifier dimming control circuit | |
| CN112969258A (en) | Infrared intelligent light modulator is got to single live wire of silicon controlled rectifier | |
| CN203340368U (en) | LED dimming table lamp | |
| CN203859905U (en) | Two-wire system light dimming circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |