CN104837252B - Method for controlling brightness of LED lamp through single live wire - Google Patents

Abstract

The invention provides a method for controlling the brightness of an LED lamp through a single live wire, wherein dimming is realized by an LED lamp single-live-wire dimming circuit which is composed of a brightness wall-controlling unit and a brightness adjustment driving unit. When brightness adjustment is required, the brightness wall-controlling unit controls and changes the phase shift angle of a voltage waveform which is output from the single live wire for transmitting a brightness control signal, and the brightness adjustment driving unit changes the brightness of the LED lamp according to the brightness grade in the brightness control signal. When the brightness wall-controlling unit transmits the brightness control signal, the output end of the single live wire outputs a guiding wave which is composed of a plurality of same phase shift angle half-waves, and a data wave which is composed of a plurality of continuous single-phase sinusoidal half-waves with different phase shift angles. Hex number system data which correspond with the data wave represents a brightness grade. The LED lamp dimming method can be used for replacement and upgrade of a common illuminating lamp which is controlled by the single live wire.

Description

A method for controlling the brightness of LED lights with a single live wire

technical field

The invention relates to a lighting lamp technology, in particular to a method for controlling the brightness of an LED lamp with a single live wire.

Background technique

Due to the nonlinear characteristics of LED lamps, the brightness of LED lamps cannot be realized by adjusting the voltage.

When using a controllable constant current source to adjust the brightness of the LED lamp, the change of the working current will cause the color shift of the LED lamp. At the same time, the load current of the LED lamp becomes very low under low brightness, which will make the controllable constant current source The lower the efficiency and the higher the temperature rise, the greater the power consumption on the driver chip will be, which will damage the life of the constant current source and the LED light source.

Using PWM (pulse width modulation) dimming method to control the brightness of LED lights can avoid the problems caused by voltage regulation and current regulation. There are three commonly used dimming methods for LED lights:

One is to use remote control. The LED light control circuit is equipped with a remote control receiving device, and the LED light can be dimmed step by step or steplessly dimmable through the remote control. The disadvantage is that one LED light needs to be equipped with a remote control, resulting in a large number of remote controls and troublesome management. , and the cost is also high.

The second is the use of digital control technology. For example, using DALI (Digital Addressable Lighting Interface) technology, the DALI system software can independently address single or multiple LED lamps on the same strong current circuit or on different circuits. The light group can be precisely dimmed and switched on and off. This solution is advanced in technology, but the cost is very high. In addition to the power line, the system also needs to lay out the control line.

The third is to adopt the single live wire switch on-off control technology. For example, using the NU102 dedicated chip, the brightness adjustment of the LED lamp can be realized by using the switch action of the ordinary wall switch within the specified time. However, this method can only provide 4 levels of adjustable brightness of LED lights, and the switching action has a time requirement.

Contents of the invention

The object of the present invention is to provide a method for dimming an LED lamp by using a single live wire without changing the wiring of the existing lighting circuit.

In order to achieve the above object, the method of the present invention is realized by a single live wire dimming circuit of the LED lamp.

The single live wire dimming of the LED lamp is composed of a brightness wall control unit and a brightness adjustment drive unit; the brightness wall control unit is provided with a single live wire input terminal and a single live wire output terminal, and the single live wire input terminal is connected to the AC power live wire The brightness adjustment drive unit is provided with a live wire input terminal and a neutral line input terminal, wherein the live wire input terminal is connected to the single live wire output terminal of the brightness wall control unit, and the neutral line input terminal is connected to the neutral line of the AC power supply; The AC power supply is single-phase 220V AC.

The brightness wall control unit sends a brightness control signal by controlling the phase shift angle of the output voltage waveform of the single live wire output terminal, and the brightness control signal is composed of a pilot wave and a data wave.

The method for sending the brightness control signal is:

Step A, setting the brightness level of the brightness control signal as brightness 1;

Step B, sending out a brightness control signal;

Step C, judging whether the brightness has changed, if the brightness has changed, return to step B; if the brightness has not changed, maintain the state of not sending out a brightness control signal, and return to step C.

The state of not sending out the brightness control signal is maintained, and the output terminal of the single live wire outputs a single-phase sine half-wave with both positive and negative half-wave phase shift angles α.

The guide wave is y consecutive single-phase half-sine waves with a phase-shift angle of β, and y is an integer greater than or equal to 1; the data wave is x single-phase half-sine waves whose phase-shift angles can be independently α or β , x is an integer greater than or equal to 2.

The brightness control signal has a total brightness of 1- N , and a total of N brightness levels; N is an integer greater than or equal to 2 and less than or equal to 2 ^x . A typical value of N is 8.

The phase shift angle β is greater than the phase shift angle α; the phase shift angle α = 4°, and the phase shift angle β = 30°.

The brightness adjustment drive unit receives the brightness control signal by the brightness signal receiving module and adjusts the brightness of the LED lamp, and the method is:

Step 1, setting the brightness level of the brightness control signal as brightness 1;

Step 2, adjust the brightness of the LED;

Step 3, judge whether there is a brightness control signal on the single live line; if there is no brightness control signal, return to step 3; if there is a brightness control signal, go to step 4;

Step 4, receiving the brightness control signal and determining the brightness level;

Step five, return to step two.

The method of judging whether there is a brightness control signal on the single live line is to judge whether there is a guide wave at the input end of the live wire; the method of receiving the brightness control signal is to receive the guide wave and the data wave in sequence; the method of determining the brightness level is to receive the The data wave is converted into an x -bit binary luminance code, and then the luminance level is obtained from the x -bit binary luminance code.

The single-phase sine half wave with a phase shift angle of β in the guide wave and the data wave adopts a phase-shift sampling pulse trigger mode; the single-phase sine half wave with a phase shift angle of α in the data wave adopts an advance trigger mode; The single-phase sine half-wave with both positive and negative half-wave phase shift angles at the single live wire output terminal adopts an uninterrupted trigger mode.

The trigger mode is adopted in advance, the starting time of the trigger pulse is before the zero crossing point, and the ending time is after the α angle after the zero crossing point.

The phase-shift sampling pulse trigger mode is adopted, and the start time of the trigger pulse is after the phase-shift sampling pulse.

The brightness wall control unit is composed of a single live wire power supply module, a rectification and phase-shifting drive module, a waveform sampling and shaping module, a single-chip microcomputer control module, a trigger control module, and a brightness setting module.

The single-chip microcomputer control module is the minimum system of the wall-controlled single-chip microcomputer, which has a brightness given signal input terminal, a phase-shift sampling pulse input terminal, and a trigger signal output terminal.

The rectification phase-shift drive module is a unidirectional thyristor AC phase-shift switch circuit, which is composed of a unidirectional thyristor and a single-phase bridge rectifier circuit; The live wire output terminal; the positive terminal of the rectification output of the single-phase bridge rectifier circuit is the full-wave rectification terminal, and the negative terminal of the rectification output is the common ground; the anode and cathode of the one-way thyristor are respectively connected to the full-wave rectification terminal and the common ground.

The single live wire power supply module is a DC/DC voltage stabilizing circuit, the input end is connected to the full-wave rectification end, and the output end outputs a single live wire control power supply to supply power to the single-chip microcomputer control module; the DC/DC voltage stabilizing circuit has a wide range of voltage input characteristic.

The waveform sampling and shaping module is a resistance voltage divider circuit, the input end is connected to the full-wave rectification end, and the output end outputs a phase-shifted sampling pulse; the phase-shifted sampling pulse is limited by a voltage regulator tube and connected to the single-chip microcomputer control module.

The brightness setting module outputs a brightness setting signal and sends it to the single-chip microcomputer control module.

The trigger signal input terminal of the trigger control module is connected to the single-chip microcomputer control module, and the output terminal is connected to the control pole of the one-way thyristor.

The brightness adjustment driving unit is composed of a single-phase rectifying and stabilizing power supply module, a brightness signal receiving module, and a brightness driving module.

The single-phase rectifying and stabilizing power supply module is composed of a single-phase transformer, a single-phase rectifying bridge circuit, and a filtering and stabilizing circuit; the input terminal of the single-phase transformer is connected to the input terminal of the live line and the input terminal of the neutral line; The AC input terminal of the phase rectification bridge circuit; the positive terminal of the rectification output of the single-phase rectification bridge circuit is the DC working power supply, and the negative terminal is the reference ground; the input terminal of the filter and voltage stabilizing circuit is connected to the DC working power supply; the output terminal of the filter and stabilizing circuit output regulates the DC power supply Supply power to the brightness signal receiving module.

The brightness signal receiving module is composed of a minimum system for adjusting a single-chip microcomputer, and a brightness signal sampling and shaping circuit.

The minimum system for adjusting the single-chip microcomputer is provided with a pulse catch input terminal and a PWM pulse output terminal.

The brightness signal sampling and shaping circuit is composed of a full-wave rectification circuit and a voltage regulator limiting circuit; the input end of the full-wave rectification circuit is connected to the output end of the single-phase transformer; the input end of the voltage regulator limiting circuit is connected to the output of the full-wave rectification circuit The terminal and the output terminal are connected to the pulse catch input terminal of the minimum system for adjusting the single chip microcomputer.

The LED driver module is provided with a DC input terminal, an LED lamp driver terminal, and a PWM brightness adjustment signal input terminal; the DC input terminal of the LED driver module is connected to a DC working power supply, and the PWM brightness adjustment signal input terminal is connected to the PWM for adjusting the minimum system of the single chip microcomputer. The pulse output terminal and the LED lamp driving terminal are connected to the LED lamp.

The beneficial effect of the present invention is that the brightness of the LED lamp is controlled by a single live wire, without the need for a remote control, without a control line, and without re-laying the power cord, and can realize the replacement and upgrading of ordinary lighting lamps; the brightness of the LED lamp can be divided into any level according to needs ;The brightness control signal is only sent in a small-angle phase-shifting method when changing the brightness, and the brightness control signal composed of a limited number of half-sine waves is output, and the time is short, which will not cause the LED light to flicker.

Description of drawings

Figure 1 is a block diagram of the system structure.

Fig. 2 is a structural diagram of the brightness wall control unit.

Fig. 3 is a circuit diagram of an embodiment of a brightness wall control unit.

Fig. 4 is an example of a waveform when the brightness wall control unit maintains the state of not sending a brightness control signal.

Fig. 5 is an example of a waveform when the brightness wall control unit sends a brightness control signal.

Fig. 6 is a flow chart of sending brightness control signals.

Fig. 7 is a control method for sending a brightness control signal.

FIG. 8 is a structural diagram of a brightness adjustment driving unit.

Fig. 9 is an embodiment of the brightness adjustment driving unit.

FIG. 10 is a method for receiving a brightness control signal.

detailed description

The present invention will be described in further detail below with reference to the accompanying drawings and examples, but the embodiments of the present invention are not limited thereto.

The structure of an embodiment of an LED lamp single live wire dimming circuit for realizing the method of the present invention is shown in FIG. 1 , which consists of a brightness wall control unit and a brightness adjustment drive unit connected in series. The brightness wall control unit has a single live line L input and a single live line L1 output; the brightness adjustment drive unit has a live line L1 input and a neutral line N output.

The structure of the brightness wall control unit is shown in Figure 2. It consists of a single live wire power supply module, a rectification phase-shifting drive module, a waveform sampling and shaping module, a single-chip microcomputer control module, a trigger control module, and a brightness setting module.

The embodiment circuit of the brightness wall control unit is shown in FIG. 3 .

The rectification phase-shift driving module is a one-way thyristor AC phase-shift switch circuit, which is composed of diode D01, diode D02, diode D03, diode D04, and one-way thyristor V01. Diode D01, diode D02, diode D03, and diode D04 form a single-phase bridge rectifier circuit, and its two AC input terminals are single live wire input end L and single live wire output end L1. The positive terminal of the rectification output of the single-phase bridge rectifier circuit is the full-wave rectification terminal A, and the negative terminal of the rectification output is the common ground. The anode and cathode of the one-way thyristor V01 are respectively connected to the full-wave rectification terminal A and the common ground.

The single live wire power supply module is a DC/DC voltage stabilizing circuit. In the embodiment shown in Figure 3, the single live wire power supply module is composed of a DC/DC regulator U1, a three-terminal regulator U2, a resistor R1, a diode D1, a capacitor C1, a capacitor C2, a capacitor C3, and a capacitor C4. The model of the regulator U1 is DY10, and the model of the three-terminal regulator U2 is HT7333. Capacitor C1, resistor R1, and capacitor C2 form a π-type filter circuit; the input of the π-type filter circuit is connected to the cathode of the diode D1, and the output is connected to the input terminal of the DC/DC regulator U1; the anode of the diode D1 is connected to the full-wave rectifier terminal A; The input terminal of the three-terminal regulator U2 is connected to the output terminal of the DC/DC regulator U1, and the output terminal is the single live wire control power supply VDD; the capacitor C3 is the output filter capacitor of the DC/DC regulator U1, and the capacitor C4 is the three-terminal stabilizer The output filter capacitor of the transformer U2.

The HT7333 outputs +3.3V voltage. If the output voltage of the DC/DC voltage regulator U1 meets the power supply requirements of the microcontroller control module, the three-terminal voltage regulator U2 can be omitted. The DC/DC voltage regulator U1 can also select other DC/DC voltage regulators with a wide range of voltage input characteristics.

The waveform sampling and shaping module is a resistor divider circuit. In the embodiment shown in Fig. 3, the waveform sampling and shaping module is composed of a resistor R01, a resistor R02, and a regulator tube DW01. The series connection point of the resistor R01 and the resistor R02 is the output terminal, which outputs the phase-shifted sampling pulse; the other terminal of the resistor R01 is the input terminal, which is connected to the full-wave rectification terminal A. The voltage regulator tube DW01 is connected in parallel to both ends of the resistor R02 to limit the phase-shifted sampling pulse.

In the embodiment shown in Figure 3, the trigger control module is composed of triode V1, voltage regulator DW1, resistor R2, resistor R3, resistor R4, and resistor R5; the collector of transistor V1 is connected to the anode of voltage regulator DW1 in series with resistor R2, and the voltage regulator The cathode of DW1 is connected to the full-wave rectifier terminal A; the emitter of the triode V1 is connected to the common ground through the resistor R3; the base of the triode V1 is connected to one end of the resistor R4 and the resistor R5 respectively; the other end of the resistor R4 is connected to the common ground; the emitter of the triode V1 The very trigger signal output end is connected to the control pole of the one-way thyristor V01; the other end of the resistor R5 is the trigger signal input end.

In the embodiment shown in Fig. 3, the brightness setting module adopts the pulse potentiometer WP. The common terminal COM of the pulse potentiometer WP is connected to the common ground. When the pulse potentiometer WP rotates, its pulse output terminal SL and pulse output terminal SR output pulses with a phase difference of 90°.

The single-chip microcomputer control module is the smallest system of the wall-controlled single-chip microcomputer. In the embodiment shown in Fig. 3, the minimum system of the wall-controlled single-chip microcomputer is composed of the wall-controlled single-chip microcomputer U3 and the crystal oscillator XT1, and the model of the wall-controlled single-chip microcomputer U3 is MSP430G2553. In the embodiment shown in Fig. 3, P2.0 and P2.1 of the wall control microcontroller U3 are the input terminals of the given brightness signal, which are respectively connected to the pulse output terminal SL and the pulse output terminal SR of the pulse potentiometer WP; P2.2 is the phase shift The sampling pulse input terminal is connected to the waveform sampling shaping module as a resistor divider circuit. In the embodiment of Fig. 3, the phase-shift sampling pulse output terminal of the waveform sampling shaping module; P1.1 is the trigger signal output terminal, which is connected to the trigger signal input terminal of the trigger control module.

The brightness wall control unit sends the brightness control signal by controlling the phase shift angle of the output voltage waveform of the single live wire output terminal L1. In the brightness control signal, single-phase sine half-waves with different phase-shift angles are used to represent different symbols in the carry counting system for the brightness level, and multiple single-phase sine-half waves with different phase-shift angles in succession form a data wave, and the carry corresponding to the data wave Counting data indicates the brightness level; the brightness control signal has a total brightness of 1- N , and a total of N brightness levels; N is an integer greater than or equal to 2, and the typical value is 8.

The brightness control signal is controlled and sent by the brightness wall control unit only when the pulse potentiometer WP is rotated and there is a brightness given signal. When the brightness wall control unit maintains the state of not sending brightness control signals, the single-chip microcomputer control module adopts an uninterrupted trigger mode to continuously send out trigger signals. The waveforms of key points of the brightness wall control unit are shown in Figure 4.

When the AC power crosses zero, the one-way thyristor V01 is turned off. After the AC power supply crosses zero, although the single-chip control module continues to send out uninterrupted trigger signals, only when the voltage of the full-wave rectifier terminal A is greater than the voltage regulation value of the voltage regulator DW1, the transistor V1 is turned on, and the one-way thyristor V01 can be activated. trigger conduction. Therefore, the AC voltage waveform of the single live wire output terminal L1 is shown in Figure 4(a), and each half-wave triggers conduction at a phase shift angle α. The voltage waveform of the full-wave rectifier terminal A is shown in Figure 4(b). The voltage waveform of the full-wave rectifier terminal A is a narrow voltage pulse, and its pulse amplitude is determined by the voltage regulation value of the regulator tube DW1, and its function is to provide the open-state power supply voltage for the single live wire power module. Since the output voltage of the DC/DC voltage regulator DY10 can still be above 5.8V when the DC voltage is input at 12V, it is sufficient that the voltage regulation value of the voltage regulator tube DW1 is greater than 12V. When the regulated voltage value of the regulator tube DW1 is 20V, the phase shift angle α = 4°.

Figure 5 shows an example of the waveform when the brightness wall control unit sends the brightness control signal. Figure 5 sends the brightness control signal of brightness 4. Figure 5(a) is the AC voltage waveform of the single live wire output terminal L1 during the transmission process, and Figure 5(b) is the voltage waveform of the full-wave rectifier terminal A during the transmission process. Figure 5(c) is a pulse schematic diagram of the phase-shifted sampling pulse in the transmission process. When drawing Figure 5(c), pulse 9, pulse 10, pulse 11, pulse 12, and pulse 13 have been idealized, that is, the signal is lower than When the high-level threshold is high, it is low-level processing, and when it is higher than the high-level threshold, it is high-level processing.

When it is necessary to send a brightness control signal, the single-chip microcomputer control module stops continuously sending uninterrupted trigger signals. In Figure 5(a), pulse 1 is a pulse before the continuous sending of uninterrupted trigger signals. After pulse 1, the MCU control module stops sending continuous uninterrupted trigger signals and enters the controllable trigger state. In the controllable trigger state, there are two trigger modes for the single-chip microcomputer control module, one is the trigger mode in advance, and the phase shift angle is α; the other is the phase shift sampling pulse trigger mode, and the phase shift angle is β.

In Figure 5(a), pulse 2, pulse 3, pulse 4, pulse 5, pulse 6, and pulse 7 form an AC voltage waveform that sends a brightness control signal at the output terminal L1 of the single live wire, among which, pulse 2, pulse 3, pulse 4 is three guide waves with a phase shift angle of β, and pulse 5, pulse 6, and pulse 7 are data waves with a phase shift angle of α or β. In the data wave, the phase shift angle of α represents binary bit 0, the phase shift angle of β represents binary bit 1, pulse 5, pulse 6, and pulse 7 form a 3-bit binary brightness code, and the range of brightness code is 000-111, representing The brightness level range is brightness 1-8. In Figure 5(a), the brightness code is 011, representing brightness level 4. The number of data waves can also be other than 3 and other values greater than or equal to 2. For example, when the number of data waves is 4, a 4-bit binary brightness code can be formed, and the maximum range of brightness levels represented can be 16 levels, namely Brightness 1-16. When the number of data waves is x , the represented brightness level range can reach 2 ^x levels at most; x is an integer greater than or equal to 2. The number of guiding waves can also be y other than 3, and y is an integer greater than or equal to 1.

After one brightness control signal is sent, the single-chip microcomputer control module starts to continuously send out uninterrupted trigger signals. In Figure 5(a), pulse 8 is the first pulse with a phase shift angle of α after the uninterrupted trigger signal is issued continuously.

When the phase-shift sampling pulse trigger mode is adopted, the start time of the trigger pulse is after the phase-shift sampling pulse. The principle of the phase-shift sampling pulse trigger mode is as follows: the one-way thyristor V01 is turned off when the AC power zero crosses after the single-chip control module does not send out a trigger signal. After zero crossing, even if it reaches the phase shift angle α, because there is no trigger signal, the one-way thyristor V01 is still turned off, and the voltage of the full-wave rectification terminal A continues to rise. Reasonably select the voltage division ratio of resistor R01 and resistor R02 in the waveform sampling and shaping module, so that when the phase shift angle β is reached, the voltage of the full-wave rectifier terminal A rises to the phase shift of the sampling point B of the phase shift sampling pulse signal after voltage division The sampling pulse changes from low level to high level. After receiving the high-level phase-shift sampling pulse signal, the single-chip control module sends a trigger signal, the one-way thyristor V01 is turned on, the phase-shift sampling pulse disappears, and becomes low level, and the phase-shift sampling pulse trigger process ends. The typical value of the phase-shift angle β is 30°, and the high-level threshold of the phase-shift sampling pulse is set to 1.5V, and the value of the resistor R01 is 100 times that of the resistor R02. In Fig. 4, because the voltage peak value of the full-wave rectification terminal A is small, there is no phase-shifting sampling pulse in Fig. 4(c).

When a brightness control signal needs to be sent out, the single-chip microcomputer control module first sends out a guide wave with a phase shift angle of β. In the embodiment shown in Fig. 5, the three guide waves with a phase shift angle of β are all triggered by a phase shift sampling pulse.

Among the data waves, there are data waves with a phase shift angle of α and data waves with a phase shift angle of β. When it is necessary to send a data wave with a phase-shift angle of β, the phase-shift sampling pulse trigger method is also adopted, and the single-chip microcomputer control module does not send a trigger signal before the zero-crossing point of the AC power supply. When reaching the phase-shift angle β after crossing zero, the single-chip microcomputer control module sends a trigger signal after receiving a high-level phase-shift sampling pulse signal. When it is necessary to send a data wave with a phase shift angle of α, the single-chip control module adopts an early trigger method, and sends a trigger signal before the zero crossing of the AC power supply, and the trigger signal lasts until the zero crossing of the AC power supply and ends after passing the phase shift angle α; The time point at which the trigger signal is sent out before the zero crossing point is calculated by the single-chip microcomputer according to the received time of the phase-shifted sampling pulse signal triggering the last guide wave.

In the data wave, the single-phase sine half wave with a phase shift angle of α is triggered in advance, and the trigger pulse in the early trigger mode starts before the zero-crossing point and ends after the α angle after the zero-crossing. Taking Figure 5 as an example, the phase shift angle of the first data wave is α, and the trigger mode needs to be adopted in advance. Before the zero-crossing point; taking the phase shift angle β as a typical value of 30° as an example, the starting moment of the early triggering can be between 30° and 180°, converted into time, the starting moment of the early triggering can be at the end of the last guide wave Between 0 and 8.33ms after the phase-shifted sampling pulse signal. For example, the MCU control module sends a trigger signal with a duration of 5ms 5ms after the phase-shift sampling pulse signal of the last guide wave, or sends a trigger signal with a duration of 6ms 5ms after the phase-shift sampling pulse signal of the last guide wave The trigger signal, or sending a trigger signal with a duration of 3ms 7ms after the phase-shifted sampling pulse signal of the last guide wave, etc., all meet the requirements of the first data wave trigger mode in advance.

If the phase shift angle of the first data wave is not α, but the phase shift angle of other data waves is α, it is only necessary to determine which data wave has a phase shift angle of α. If the phase shift angle of the second data wave is α, the start time of its early trigger is 10ms later than the start time of the first data wave; if the phase shift angle of the third data wave is α , then the start time of the early trigger is 20ms behind the start time of the first data wave, and so on. For example, when the phase-shift angle of the second data wave is α, the MCU control module sends a trigger signal with a duration of 5ms 15ms after the phase-shift sampling pulse signal of the last guide wave, which satisfies the early trigger mode of the second data wave requirements.

The process of sending a brightness control signal by the single-chip microcomputer control module is shown in Figure 6, and the steps are as follows:

Step 1, stop continuously sending out uninterrupted trigger signals, and exit the state of maintaining no brightness control signal;

Step 2, send the guide wave;

Step 3, send data waves;

In step 4, the sending of the brightness control signal is ended, and the state of maintaining no sending of the brightness control signal is entered.

The method for sending the brightness control signal by the brightness wall control unit is shown in Figure 7, including:

Step A, setting the brightness level of the brightness control signal as brightness 1;

Step B, sending out a brightness control signal;

Step C, judging whether the brightness has changed, if the brightness has changed, return to step B; if the brightness has not changed, maintain the state of not sending out a brightness control signal, and return to step C.

The structure of an embodiment of the brightness adjustment driving unit is shown in FIG. 8 , which consists of a single-phase rectification and voltage stabilization power supply module, a brightness signal receiving module, and a brightness driving module.

The single-phase rectification and voltage stabilization power supply module is composed of a single-phase transformer, a single-phase rectification bridge circuit, and a filter and voltage stabilization circuit; the input terminal of the single-phase transformer is connected to the input terminal L1 of the live line and the input terminal N of the neutral line; The AC input terminal of the phase rectification bridge circuit; the positive terminal of the rectification output of the single-phase rectification bridge circuit is the DC working power supply, and the negative terminal is the reference ground; the input terminal of the filter and voltage stabilizing circuit is connected to the DC working power supply; the output of the filter and stabilizing circuit adjusts the DC power supply to The brightness signal receiving module supplies power.

The brightness signal receiving module is composed of a minimum system for adjusting single-chip microcomputer and a circuit for sampling and shaping brightness signals. The minimum system for adjusting single-chip microcomputer is provided with a pulse capture input terminal and a PWM pulse output terminal.

The brightness signal sampling and shaping circuit is composed of a full-wave rectification circuit and a regulator tube limiting circuit; the input end of the full-wave rectification circuit is connected to the output end of a single-phase transformer. The input end of the regulator tube limiting circuit is connected to the output end of the full-wave rectification circuit, and the output end is connected to the pulse catch input end of the minimum system of the single-chip microcomputer.

The LED driving module is provided with a DC input terminal, an LED lamp driving terminal, and a PWM brightness adjustment signal input terminal. The DC input terminal of the LED driver module is connected to the DC working power supply, the PWM brightness adjustment signal input terminal is connected to the PWM pulse output terminal of the single-chip microcomputer, and the LED lamp driving terminal is connected to the LED lamp.

An embodiment of the brightness adjustment driving unit is shown in FIG. 9 .

In the embodiment shown in FIG. 9 , the single-phase rectifying and stabilizing power supply module is composed of single-phase transformer TC, diode D05, diode D06, diode D07, diode D08, capacitor C5, resistor R03, and regulator tube DW02. Among them, the diode D05, the diode D06, the diode D07, and the diode D08 form a single-phase rectifier bridge circuit, and the capacitor C5, the resistor R03, and the regulator tube DW02 form a filter and voltage stabilizing circuit. The capacitor C5 filters the output of the single-phase rectifier bridge to obtain the DC working power VIN, and the regulator DW02 outputs the regulated DC power VCC.

In the embodiment shown in FIG. 9 , the brightness signal receiving module is composed of an adjusting single-chip microcomputer U4, a crystal oscillator XT2, a diode D09, a diode D10, a resistor R6, a resistor R7, and a regulator tube DW2. Among them, the single-chip microcomputer U4 and the crystal oscillator XT2 form the minimum system of the single-chip microcomputer. The P2.0 of the single-chip microcomputer U4 is the pulse capture input terminal, and the P1.2 is the PWM pulse output terminal. The diode D09 and the diode D10 form a full-wave rectification circuit, the anodes of the diode D09 and the diode D10 are respectively connected to the output terminals L2 and N2 of the single-phase transformer, and the cathodes are connected to the output terminal of the full-wave rectification circuit. Resistor R6, resistor R7, and voltage regulator tube DW2 form a voltage regulator tube limiting circuit. One end of the resistor R6 is connected with the cathode of the regulator tube DW2 to be the output terminal of the regulator tube limiter circuit and connected to the pulse catch input terminal of the regulating single-chip microcomputer U4. The other end of the resistor R6 is the input end of the regulator tube limiting circuit and is connected to the output end of the full-wave rectification circuit. The anode of the voltage regulator DW2 is connected to the reference ground, and the resistor R7 is connected in parallel with both ends of the voltage regulator DW2.

The model of the regulating microcontroller U4 is MSP430G2553. The wall control single-chip microcomputer U3 and the adjustment single-chip microcomputer U4 can also choose other MSP430 series low-power single-chip microcomputers.

In the embodiment shown in FIG. 9 , the brightness driving module is composed of an LED constant current driver U5, an inductor LG, a resistor R8, and a fast recovery diode D2. The model of the LED constant current driver is PT4115. The two ends of the resistor R8 are respectively connected to the power supply voltage terminal VIN of the LED constant current driver U5, and the output current sensing terminal SEN; the cathode of the fast recovery diode D2 is connected to the power supply voltage terminal VIN of the LED constant current driver U5, and the anode is connected to the LED constant current driver. The switch output terminal SW of U5; one end of the inductor LG is connected to the switch output terminal SW of the LED constant current driver U5; the output current sensing terminal SEN of the LED constant current driver U5 and the other end of the inductor LG is the LED lamp driving terminal; the LED constant current driver The power supply voltage terminal VIN of U5 is the DC input terminal of the LED driver module; the dimming control terminal DIM of the LED constant current driver U5 is the input terminal of the PWM brightness adjustment signal.

The brightness adjustment drive unit receives the brightness control signal by the brightness signal receiving module and adjusts the brightness of the LED lamp, and the method is:

Step 1, setting the brightness level of the brightness control signal as brightness 1;

Step 2, adjust the brightness of the LED;

Step 3, judge whether there is a brightness control signal on the single live line; if there is no brightness control signal, return to step 3; if there is a brightness control signal, go to step 4;

Step 4, receiving a brightness control signal;

Step five, return to step two.

To judge whether there is a brightness control signal on the single live wire, the method is to judge whether there is a single-phase sine half wave with a phase shift angle of β at the input terminal L1 of the live wire; to receive the brightness control signal, the method is to receive the data wave after receiving the pilot wave. The guide wave is y consecutive single-phase half-sine waves with a phase shift angle of β, and the data wave is x single-phase half-sine waves with a phase shift angle of α or β. The x data waves whose phase shift angle is α or β can be converted into x -bit binary luminance codes to obtain the luminance level represented by the luminance control signal.

The brightness signal sampling and shaping circuit converts the AC voltage on the live wire input terminal L1 into a rectangular wave, as shown in Figure 5(d). Phase shift angle α and phase shift angle β correspond to the negative pulses shown in Figure 5(d), where phase shift angle α corresponds to pulse 14, pulse 18, and pulse 21, which are negative pulses with narrower widths; phase shift angle β corresponds to Pulse 15, pulse 16, pulse 17, pulse 19, and pulse 20 are negative pulses with a wider width. The brightness signal receiving module only needs to judge the width of the negative pulse sent to the minimum system pulse capture input terminal of the adjustment microcontroller, and then can judge whether the phase shift angle of the live wire input terminal L1 is α or β.

In Fig. 5, the moment when the MCU control module stops sending the trigger signal for the first time is the positive half wave of the AC power supply. Therefore, the first single-phase sine wave with a phase shift angle of β on the live wire input terminal L1 is the negative half wave. Since the moment when the MCU control module stops sending the trigger signal for the first time is random, the moment when the first stop sending the trigger signal may also be in the negative half wave of the AC power supply. A single-phase sine half wave with phase angle β becomes a positive half wave. Since the luminance signal sampling and shaping circuit first rectifies the AC voltage on the live wire input terminal L1, and then converts it into a rectangular wave, therefore, whether the first single-phase sine half wave with a phase shift angle of β is a positive half wave or a negative half wave does not matter. It affects the judgment and reception of the brightness control signal by the brightness adjustment drive unit.

Claims (8)

1. a kind of method that single live wire controls LED brightness, is realized by LED list live wire light adjusting circuit, it is characterised in that：

The LED list live wire light adjusting circuit is made up of brightness wall control unit, brightness regulation driver element；The brightness wall control list Unit is provided with single live wire input, single fire wire output end, and single live wire input is connected to alternating current power supply live wire；The brightness is adjusted Section driver element is provided with live wire input, zero line input, wherein, the live wire input is connected to the list of brightness wall control unit Fire wire output end, the zero line input is connected to alternating current power supply zero line；The alternating current power supply is single-phase 220V alternating currents；

The brightness wall control unit sends brilliance control letter by the phase shifting angle of the single fire wire output end output voltage waveforms of control Number, brightness control signal is by guide wave and data wave component；

It is described send brightness control signal method be：

Step A, sets the brightness degree of brightness control signal as brightness 1；

Step B, sends a brightness control signal；

Step C, judges whether brightness changes, and brightness changes, return to step B；Brightness does not change, and maintains not Send brightness control signal state, return to step C；

The maintenance does not send brightness control signal state, and it is all the single-phase of α that single fire wire output end exports positive and negative half-wave phase shifting angle Half-sinusoid；

The guide wave is continuousyIndividual phase shifting angle is the single-phase half-sinusoid of β,yIt is the integer more than or equal to 1；The data wave ForxIndividual phase shifting angle can be individually for the single-phase half-sinusoid of α or β,xIt is the integer more than or equal to 2；

The total brightness 1- of the brightness control signalN, altogetherNIndividual brightness degree；NIt is more than or equal to 2, less than or equal to 2 ^x Integer；

The phase shift angle beta is more than phase shifting angle α；

The brightness regulation driver element receives brightness control signal and adjusting brightness of LED lamps by luminance signal receiver module, its Method is：

Step one, sets the brightness degree of brightness control signal as brightness 1；

Step 2, adjusts LED luminance；

Step 3, judges whether there is brightness control signal on single live wire；Without brightness control signal, return to step three；There is brightness Control signal, goes to step 4；

Step 4, receives brightness control signal, determines brightness degree；

Step 5, return to step two；

Described to judge whether there is brightness control signal on single live wire, method is to judge whether live wire input has guide wave；It is described Brightness control signal is received, method is to receive guide wave and data wave successively；The determination brightness degree, is the data that will be received Ripple is converted toxPosition binary system brightness code, then byxPosition binary system brightness code obtains brightness degree.

2. the method that single live wire according to claim 1 controls LED brightness, it is characterised in that：The guide wave sum Phase shift sampling pulse triggering mode is taken according to single-phase half-sinusoid of the phase shifting angle in ripple for β；Phase shifting angle is α's in the data wave Single-phase half-sinusoid takes triggering mode in advance；The single fire wire output end export positive and negative half-wave phase shifting angle all for α it is single-phase just String half-wave takes uninterrupted triggering mode.

3. the method that single live wire according to claim 2 controls LED brightness, it is characterised in that：Described taking is touched in advance Originating party formula, the initial time of its trigger pulse before zero crossing, after α angles of the finish time after zero crossing.

4. the method that single live wire according to claim 2 controls LED brightness, it is characterised in that：It is described to take phase shift to take Sample pulse-triggered mode, the initial time of its trigger pulse is after phase shift sampling pulse.

5. the method that single live wire according to claim 1 controls LED brightness, it is characterised in that：Phase shifting angle α=4 ° , phase shift angle beta=30 °.

6. the method that single live wire according to claim 1 controls LED brightness, it is characterised in that：It is describedN =8 。

7. the method that single live wire according to claim 1 controls LED brightness, it is characterised in that：The brightness wall control list Unit is by single fire-wire power module, rectification phase shift drive module, waveform sampling Shaping Module, single chip control module, triggering control Module, the given module composition of brightness；

The single chip control module is wall control single-chip minimum system, with brightness Setting signal input, phase shift sampling arteries and veins Rush input, trigger outfan；

The rectification phase shift drive module is that unidirectional thyristor exchanges phase switcher circuit, whole by unidirectional thyristor and single-phase bridge Current circuit is constituted；2 ac input ends of single phase bridge type rectifier circu are respectively single live wire input, single fire wire output end；It is single The rectification output plus terminal of phase bridge rectifier is all wave rectification end, and rectification output negative terminal is for publicly；The sun of unidirectional thyristor Pole, negative electrode are respectively connecting to all wave rectification end, publicly；

Single fire-wire power module is DC/DC mu balanced circuits, and input is connected to all wave rectification end, the single live wire of outfan output Control power supply is powered to single chip control module；The DC/DC mu balanced circuits have the control source characteristic of wide scope；

The waveform sampling Shaping Module is resistor voltage divider circuit, and input is connected to all wave rectification end, outfan output phase shift Sampling pulse；Phase shift sampling pulse is by stabilivolt amplitude limit and is connected to single chip control module；

The given module output brightness Setting signal of the brightness delivers to single chip control module；

The trigger input of the trigger control module is connected to single chip control module, and outfan is connected to unidirectional crystalline substance lock Pipe control pole.

8. the method that single live wire according to claim 1 controls LED brightness, it is characterised in that：The brightness regulation is driven Moving cell is made up of single-phase rectifier power module of voltage regulation, luminance signal receiver module, brightness drive module；

The single-phase rectifier power module of voltage regulation is made up of single-phase transformer, single-phase rectifier bridge circuit, filter regulator circuit；It is single-phase Transformer inputs are connected to live wire input, zero line input；Single-phase transformer outfan is connected to single-phase rectifier bridge circuit Ac input end；Single-phase rectification bridge circuit rectifies output plus terminal is DC supply, negative terminal is reference ground；Filter regulator circuit Input is connected to DC supply；The output of filter regulator circuit outfan adjusts DC source to luminance signal receiver module Power supply；

The luminance signal receiver module is constituted by single-chip minimum system, luminance signal sampling shaping circuit is adjusted；

The regulation single-chip minimum system is provided with pulse capture input and pwm pulse outfan；

The luminance signal sampling shaping circuit is made up of full-wave rectifying circuit, stabilivolt amplitude limiter circuit；Full-wave rectifying circuit is defeated Enter end and be connected to single-phase transformer outfan；Stabilivolt amplitude limiter circuit input is connected to full-wave rectifying circuit outfan, output End is connected to the pulse capture input for adjusting single-chip minimum system；

The LED drive module is provided with direct-flow input end, LED drive end, PWM brightness regulated signal inputs；LED drives mould The direct-flow input end of block is connected to DC supply, and PWM brightness regulated signal inputs are connected to the minimum system of regulation single-chip microcomputer The pwm pulse outfan of system, LED drive end is connected to LED.