CN105592587A - LED lamp control method - Google Patents

Abstract

The invention discloses a method for controlling an LED lamp. The LED lamp comprises an AC/DC converter, a single chip microcomputer, a warm white LED lamp string, a cool white LED lamp string, a red LED lamp string, a green LED lamp string, a blue LED lamp string LED light string, radio frequency module and remote control device that cooperates with the radio frequency module; 1. The blue LED light strings are electrically connected, and the single-chip microcomputer is electrically connected with the radio frequency module, the warm white LED light strings, the cool white LED light strings, the red LED light strings, the green LED light strings, and the blue LED light strings. The invention has the characteristics of effectively eliminating voltage drop and current drop.

Description

How to control LED lights

technical field

The invention relates to the technical field of LED lighting, in particular to a control method of an LED lamp that can effectively eliminate voltage drop and current drop.

Background technique

With the application and promotion of LED in the field of lighting, more and more applications appear in our daily life, such as adjusting the brightness of the light, adjusting the color temperature, and adjusting the color.

Generally, the same-phase PWM is used for color mixing control for color temperature and color adjustment. The advantage is that the control method is simple and easy to implement.

However, the same-phase PWM signal output will cause a serious drop in the input voltage, resulting in large ripple current and stroboscopic problems, and the power supply at the input end will enter overload protection, making the LED lights unable to work normally.

Chinese patent authorization publication number: CN204062619U, authorized publication date December 31, 2014, discloses an LED lamp, including a lamp panel, several LED light bars, LED drive control devices and control switches, and the LED light bars are arranged in the lamp panel , the LED light bar is composed of an LED substrate and a plurality of LED lamp beads, and the plurality of LED lamp beads are arranged on the LED substrate, the LED drive control device is electrically connected with the plurality of LED lamp beads, and the control switch is connected to control the LED drive control device to realize Switch control of some or all LED lamp beads in single or multiple LED light strips. This invention has the deficiency of voltage drop.

Contents of the invention

The purpose of the present invention is to overcome the deficiency that the same-phase PWM signal of the LED lamp in the prior art will cause the input voltage to drop, and to provide a control method of the LED lamp that can effectively eliminate the voltage drop and the current drop.

In order to achieve the above object, the present invention adopts the following technical solutions:

A method for controlling an LED lamp, the LED lamp comprising an AC/DC converter, a single-chip microcomputer, a warm white LED lamp string, a cool white LED lamp string, a red LED lamp string, a green LED lamp string, a blue LED lamp string, The radio frequency module and the remote control device that cooperates with the radio frequency module; Serial electrical connection, the single chip microcomputer is electrically connected with the radio frequency module, warm white LED light string, cool white LED light string, red light LED light string, green light LED light string, blue light LED light string;

Including the color temperature adjustment process and the switch light process, the color temperature adjustment process includes the following steps:

(1-1) The remote control device sends a brightness adjustment command to the radio frequency module, and the single-chip microcomputer extracts a warm white brightness value Br _W and a cool white brightness value Br _c from the brightness adjustment command;

The remote control device sends a color temperature adjustment command to the radio frequency module, and the single-chip microcomputer obtains the duty cycle W of the warm white PWM signal and the duty cycle C of the cool white PWM signal according to the received color temperature adjustment command;

(1-2) The single-chip microcomputer utilizes the formula Factor_W=W/(C+W), Factor_C=C/(C+W) to calculate the warm white pulse width parameter Factor_W, and the cool white pulse width parameter Factor_C,

Use the formula temp=255×Br/100 to calculate the brightness conversion value temp;

(1-3) The single-chip microcomputer uses the formula W_Duty=temp×Factor_W, C_Duty=temp×Factor_C to calculate and obtain the warm white temperature parameter W_Duty, the cool white temperature parameter C_Duty,

(1-4) The microcontroller outputs a warm white PWM signal that meets the warm white temperature parameter W_Duty and the warm white brightness value Br _W to the warm white light string, and the microcontroller outputs a cool white PWM signal that meets the cool white temperature parameter C_Duty and the cool white brightness value Br _c The signal is given to the cool white light string; the pulses of the warm white PWM signal and the cool white PWM signal appear sequentially.

The serial port of the single-chip microcomputer establishes communication with the radio frequency module, and the radio frequency module can receive the data from the mobile phone APP or the radio frequency remote control and send it to the single-chip microcomputer through the serial port, finally realizing intelligent dimming. By sending different command codes to the MCU, various lighting effects can be realized, such as red, green, and blue 16 million color mixed light, three-color jump, gradient, seven-color jump, gradient and other effects, which can be realized when adjusting white light Brightness adjustment, color temperature adjustment, at the same time, the color temperature will not change when the brightness is adjusted, and the brightness value will not change when the color temperature is adjusted. The pulses of the warm white PWM signal and the cool white PWM signal appear sequentially, effectively eliminating voltage drop and current drop.

Therefore, the present invention has the characteristics of facilitating the adjustment of color, color temperature and brightness, realizing various changing effects of lights, and effectively eliminating voltage drop and current drop.

Preferably, it also includes a brightness adjustment process, including the following steps:

The remote control device sends a brightness adjustment command to the radio frequency module, and the single-chip microcomputer extracts the warm white brightness value BrW and the cool white brightness value Brc of the single-chip microcomputer from the brightness adjustment command, and the computer selects the larger value M of BrW and Brc, and uses the formula Calculate the ratio k of M to the current brightness Br, and Br is pre-stored in the microcontroller;

Make W times kW, C become kC, the microcontroller outputs a warm white PWM signal with a duty cycle of kW to the warm white light string, and the microcontroller outputs a cool white PWM signal with a duty cycle of kC to the cool white light string.

Preferably, during the brightness adjustment process, when the single-chip microcomputer outputs the PWM signal to the warm white light string or the cool white light string, compare the PWM duty cycle value A in the received adjustment command with the current duty cycle value B, if A >B, the duty ratio of the output PWM signal increases stepwise until A≤B; if A<B, the duty ratio of the output PWM signal decreases stepwise until A≥B.

As preferably, it also includes red, green and blue adjustment process, including the following steps:

The remote control device sends an RGB dimming command to the RF module, and the single-chip microcomputer obtains the red light PWM duty cycle, the green light PWM duty cycle and the blue light PWM duty cycle from the RGB dimming command, and the single-chip microcomputer output meets the red light PWM duty cycle, green light PWM duty cycle 3-way PWM signal of light PWM duty cycle and blue-light PWM duty cycle, and make the pulses of 3-way PWM signal appear in sequence.

Preferably, the warm white LED light strings, the cool white LED light strings, the red LED light strings, the green LED light strings and the blue LED light strings each include several lamp beads connected in series.

Preferably, the process of switching lights includes the following steps:

The remote control device sends the switch light command to the radio frequency module, and the single-chip microcomputer judges whether the current LED light is in the light off state or the light on state, and if the switch light command is consistent with the current switch light state, the current state remains unchanged;

If the switch light command is inconsistent with the current switch light state, the MCU saves the current state, and sends a message to warm white LED light strings, cool white LED light strings, red light LED light strings, green light LED light strings, and blue light LED light strings. The command corresponds to the switch light PWM signal.

Preferably, the remote control device is a remote control or a mobile phone.

Preferably, the radio frequency module is a wifi module, a bluetooth module or a zigbee module.

Therefore, the present invention has the following beneficial effects: it is convenient to adjust the color, color temperature and brightness, can realize various changing effects of lights, and effectively eliminates voltage drop and current drop.

Description of drawings

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

FIG. 2 is a timing diagram of PWM signal control in the brightness adjustment process in the prior art;

Fig. 3 is a kind of PWM signal control timing diagram in the RGB adjustment process in the prior art;

Fig. 4 is a timing diagram of PWM signal control in the white light dimming process of the present invention;

Fig. 5 is a kind of PWM signal control timing diagram in the white light 50% brightness dimming process of the present invention;

FIG. 6 is a timing diagram of PWM signal control in the cyan 50% brightness dimming process of the present invention.

In the figure: AC/DC converter 1, single chip microcomputer 2, warm white LED light string 3, cool white LED light string 4, red LED light string 5, green LED light string 6, blue LED light string 7, radio frequency module 8 , remote control device 9.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

The embodiment shown in Figure 1 is a control method for LED lamps. The LED lamps include an AC/DC converter 1, a single-chip microcomputer 2, a warm white LED lamp string 3, a cool white LED lamp string 4, and a red LED lamp string 5 , green LED lamp string 6, blue LED lamp string 7, radio frequency module 8 and the remote control device 9 that cooperates with the radio frequency module; , red LED light strings, green LED light strings, and blue LED light strings are electrically connected, and the single-chip microcomputer is respectively connected to the radio frequency module, warm white LED light strings, cool white LED light strings, red LED light strings, green LED light strings, The blue LED light strings are electrically connected; the remote control device is a mobile phone, and the radio frequency module is a wifi module. Warm white LED light strings, cool white LED light strings, red LED light strings, green LED light strings and blue LED light strings each include 6 LED beads connected in series.

Including the color temperature adjustment process and the switch light process, the color temperature adjustment process includes the following steps:

Step 100, the remote control device sends a brightness adjustment command to the radio frequency module, and the single-chip microcomputer extracts the warm white brightness value Br _W and the cool white brightness value Br _c from the brightness adjustment command;

The remote control device sends a color temperature adjustment command to the radio frequency module, and the single-chip microcomputer obtains the duty cycle W of the warm white PWM signal and the duty cycle C of the cool white PWM signal according to the received color temperature adjustment command;

Step 200, the single-chip microcomputer uses the formula Factor_W=W/(C+W), Factor_C=C/(C+W) to calculate the warm white pulse width parameter Factor_W, the cool white pulse width parameter Factor_C,

Use the formula temp=255×Br/100 to calculate the brightness conversion value temp;

Step 300, the single-chip microcomputer uses the formula W_Duty=temp×Factor_W, C_Duty=temp×Factor_C to calculate and obtain the warm white temperature parameter W_Duty, the cold white temperature parameter C_Duty,

In step 400, the microcontroller outputs a warm white PWM signal satisfying the warm white temperature parameter W_Duty and the warm white brightness value Br _W to the warm white light string, and the microcontroller outputs a cool white PWM signal satisfying the cool white temperature parameter C_Duty and the cool white brightness value Br _c to the Cool white light string; pulses of warm white PWM signal and cool white PWM signal appear in sequence.

It also includes a brightness adjustment process, including the following steps:

The remote control device sends a brightness adjustment command to the radio frequency module, and the single-chip microcomputer extracts the warm white brightness value BrW and the cool white brightness value Brc of the single-chip microcomputer from the brightness adjustment command, and the computer selects the larger value M of BrW and Brc, and uses the formula Calculate the ratio k of M to the current brightness Br, and Br is pre-stored in the microcontroller;

Make W times kW, C become kC, the microcontroller outputs a warm white PWM signal with a duty cycle of kW to the warm white light string, and the microcontroller outputs a cool white PWM signal with a duty cycle of kC to the cool white light string.

During the brightness adjustment process, when the microcontroller outputs a PWM signal to a warm white light string or a cool white light string, compare the PWM duty cycle value A in the received adjustment command with the current duty cycle value B, if A>B, Then make the duty cycle of the output PWM signal stepwise increase until A≤B; if A<B, then make the duty cycle of the output PWM signal decrease stepwise until A≥B.

It also includes the red, green and blue adjustment process, including the following steps:

The remote control device sends an RGB dimming command to the RF module, and the single-chip microcomputer obtains the red light PWM duty cycle, the green light PWM duty cycle and the blue light PWM duty cycle from the RGB dimming command, and the single-chip microcomputer output meets the red light PWM duty cycle, green light PWM duty cycle 3-way PWM signal of light PWM duty cycle and blue-light PWM duty cycle, and make the pulses of 3-way PWM signal appear in sequence.

The process of switching lights includes the following steps:

The remote control device sends the switch light command to the radio frequency module, and the single-chip microcomputer judges whether the current LED light is in the light off state or the light on state, and if the switch light command is consistent with the current switch light state, the current state remains unchanged;

If the switch light command is inconsistent with the current switch light state, the MCU saves the current state, and sends a message to warm white LED light strings, cool white LED light strings, red light LED light strings, green light LED light strings, and blue light LED light strings. The command corresponds to the switch light PWM signal.

As shown in Fig. 2 and Fig. 3, in the PWM signal control timing diagram in the prior art, the pulses of PWM1 signal and PWM2 signal appear simultaneously within time t1, and the pulses of PWM3 signal, PWM4 signal and PWM5 signal appear simultaneously within time t1 Appeared, the PWM signal output in the same phase will cause a serious drop in the input voltage, resulting in a large ripple current and flicker. In a more serious situation, the power supply at the input end will enter overload protection, making the LED lights unable to work normally.

In this embodiment, a 30W/24V AC/DC converter is selected, PWM3 controls red light, PWM4 controls green light, and PWM5 controls blue light; PWM dimming frequency is 1KHz (period 1ms).

As shown in Figure 4, when the microcontroller receives the dimming command for white light output, PWM3, PWM4, and PWM5 are turned on sequentially within one switching cycle;

As shown in Figure 5, when the single-chip microcomputer receives the dimming command of 50% brightness of white light, within a dimming cycle, PWM3 outputs 1/6ms high level and then turns low level, PWM4 outputs 1/6ms high level and then Turn to low level, PWM5 output 1/6ms high level and then turn to low level.

As shown in Figure 6, when the MCU receives a cyan (green-blue synthesis) dimming command with 50% brightness, within a dimming cycle, PWM3 outputs a low level, and PWM4 outputs a 1/6ms high level and then turns low Level, PWM5 outputs 1/6ms high level and then turns low level.

In the present invention, the pulses of PWM1 signal and PWM2 signal appear sequentially, and the pulses of PWM3 signal, PWM4 signal and PWM5 signal appear sequentially, thereby effectively eliminating voltage drop and current drop.

It should be understood that this embodiment is only used to illustrate the present invention but not to limit the scope of the present invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Claims (8)

1. A control method for an LED lamp, said LED lamp comprising an AC/DC converter (1), a single-chip microcomputer (2), a warm white LED lamp string (3), a cool white LED lamp string (4), a red LED Light strings (5), green LED light strings (6), blue LED light strings (7), radio frequency modules (8) and remote control devices (9) cooperating with the radio frequency modules; AC/DC converters are respectively connected with the radio frequency modules, Single-chip microcomputer, warm white LED light string, cool white LED light string, red light LED light string, green light LED light string, blue light LED light string are electrically connected, the single-chip microcomputer is connected with the RF module, warm white LED light string, cool white LED light string respectively , the red LED light string, the green LED light string, and the blue LED light string are electrically connected; it is characterized in that, Including the color temperature adjustment process and the switch light process, the color temperature adjustment process includes the following steps: (1-1) The remote control device sends a brightness adjustment command to the radio frequency module, and the single-chip microcomputer extracts a warm white brightness value Br _W and a cool white brightness value Br _c from the brightness adjustment command; The remote control device sends a color temperature adjustment command to the radio frequency module, and the single-chip microcomputer obtains the duty cycle W of the warm white PWM signal and the duty cycle C of the cool white PWM signal according to the received color temperature adjustment command; (1-2) The single-chip microcomputer utilizes the formula Factor_W=W/(C+W), Factor_C=C/(C+W) to calculate the warm white pulse width parameter Factor_W, and the cool white pulse width parameter Factor_C, Use the formula temp=255×Br/100 to calculate the brightness conversion value temp; (1-3) The single-chip microcomputer uses the formula W_Duty=temp×Factor_W, C_Duty=temp×Factor_C to calculate and obtain the warm white temperature parameter W_Duty, the cool white temperature parameter C_Duty, (1-4) The microcontroller outputs a warm white PWM signal that meets the warm white temperature parameter W_Duty and the warm white brightness value Br _W to the warm white light string, and the microcontroller outputs a cool white PWM signal that meets the cool white temperature parameter C_Duty and the cool white brightness value Br _c The signal is given to the cool white light string; the pulses of the warm white PWM signal and the cool white PWM signal appear sequentially. 2. The method for controlling LED lamps according to claim 1, further comprising a brightness adjustment process comprising the following steps: The remote control device sends a brightness adjustment command to the radio frequency module, and the single-chip microcomputer extracts the warm white brightness value BrW and the cool white brightness value Brc of the single-chip microcomputer from the brightness adjustment command, and the computer selects the larger value M of BrW and Brc, and uses the formula Calculate the ratio k of M to the current brightness Br, and Br is pre-stored in the microcontroller; Make W times kW, C become kC, the microcontroller outputs a warm white PWM signal with a duty cycle of kW to the warm white light string, and the microcontroller outputs a cool white PWM signal with a duty cycle of kC to the cool white light string. 3. The control method of LED lamps according to claim 2, characterized in that, during the brightness adjustment process, when the single-chip microcomputer outputs a PWM signal to a warm white light string or a cool white light string, the PWM signal in the received adjustment command The duty cycle value A is compared with the current duty cycle value B. If A>B, the duty cycle of the output PWM signal is increased stepwise until A≤B; if A<B, the output PWM signal is The duty cycle of the step decreases until A≥B. 4. The control method of LED lamps according to claim 1, further comprising a red, green and blue adjustment process, including the following steps: The remote control device sends an RGB dimming command to the RF module, and the single-chip microcomputer obtains the red light PWM duty cycle, the green light PWM duty cycle and the blue light PWM duty cycle from the RGB dimming command, and the single-chip microcomputer output meets the red light PWM duty cycle, green light PWM duty cycle 3-way PWM signal of light PWM duty cycle and blue-light PWM duty cycle, and make the pulses of 3-way PWM signal appear in sequence. 5. The control method of LED lights according to claim 1, wherein the warm white LED light strings, the cool white LED light strings, the red LED light strings, the green LED light strings and the blue LED light strings all include several lamp beads connected in series. 6. The control method of LED lights according to claim 1, characterized in that, the process of switching lights comprises the following steps: The remote control device sends the switch light command to the radio frequency module, and the single-chip microcomputer judges whether the current LED light is in the light off state or the light on state, and if the switch light command is consistent with the current switch light state, the current state remains unchanged; If the switch light command is inconsistent with the current switch light state, the MCU saves the current state, and sends a message to warm white LED light strings, cool white LED light strings, red light LED light strings, green light LED light strings, and blue light LED light strings. The command corresponds to the switch light PWM signal. 7. The method for controlling an LED lamp according to claim 1 or 2 or 3 or 4 or 5 or 6, wherein the remote control device is a remote control or a mobile phone. 8. The method for controlling an LED lamp according to claim 1 or 2 or 3 or 4 or 5 or 6, wherein the radio frequency module is a wifi module, a bluetooth module or a zigbee module.