Dimming power supply based on Modbus networking

Abstract

The utility model discloses a dimming power supply based on Modbus networking, and aims to solve the technical problems of high remote dimming cost and poor reliability of an existing LED light source. The system comprises a mobile control terminal, a main light modulator which is in wireless communication connection with the mobile control terminal, and a plurality of sub light modulators which are in RS485 communication connection with the main light modulator. The main light modulator and the sub light modulator respectively comprise a rectification filtering module which is correspondingly and electrically connected with the commercial power, a power output module which is correspondingly and electrically connected with the rectification filtering module, an RS485 module which is used for Modbus networking, and a main control module which is in communication connection with the RS485 module and is used for responding to a regulation and control signal. The voltage sampling feedback module is electrically connected between the output end and the input end of the output module, and the regulation and control output module is electrically connected between the sampling input end of the voltage sampling feedback module and the main control module. The dimming power supply is high in safety and good in stability, and the dimming effect can be synchronized and consistent.

Description

Technical Field

[0001] The present application relates to the technical field of dimming devices, and particularly to a dimming power supply based on Modbus networking. Background Art

[0002] LED light sources, i.e., light-emitting diode light sources, are widely used in the lighting field. The luminous efficiency of LED light sources is significantly improved compared to that of traditional light sources, which means that LED light sources can consume less electric energy when providing the same lighting effect. In addition, LED light sources use electronic light field radiation to emit light, with fewer problems such as heat deposition and light attenuation, relatively long service life, and high safety and reliability in use.

[0003] LED light sources often face dimming requirements in actual use to adapt to different lighting and environmental atmosphere requirements. However, the brightness adjustment of existing LED light sources requires connecting multiple devices such as a switching power supply and a dimmer at the same time to achieve, and the wiring construction and dimming operation settings are relatively complex, with high material and labor costs. In addition, with the popularization of intelligent mobile devices such as mobile phones and the rapid development of Internet of Things technology, mobile phone control technology is becoming more and more popular among people. For example, the ordinary switching power supply known to the inventor does not have a dimming function and needs to be used in combination with a dimmer to achieve the dimming function, with a high equipment cost. In addition, it cannot be remotely controlled through a smart phone, nor can it achieve automatic dimming, resulting in unstable brightness; in addition, the inventor also knows a wireless networking dimming power supply, which can remotely dim multiple devices, but because the entire networking network is wireless, there are relatively large problems with the communication stability and security.

[0004] The information disclosed in this background art section is only for deepening the understanding of the background art of the present disclosure, and should not be regarded as an admission or any form of suggestion that this information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0005] In view of at least one of the above technical problems, the present disclosure provides a dimming power supply based on Modbus networking, aiming to solve the technical problems of high cost and poor reliability in remote dimming of existing LED light sources.

[0006] According to one aspect of the present disclosure, a dimming power supply based on Modbus networking is provided, which includes a mobile control terminal, a main dimmer wirelessly communicatively connected to the mobile control terminal, and a plurality of sub-dimmers RS485 communicatively connected to the main dimmer; the main dimmer and the sub-dimmers respectively include a rectification and filtering module electrically connected to the mains electricity correspondingly, a power output module electrically connected to the rectification and filtering unit correspondingly, an RS485 module for Modbus networking, a main control module communicatively connected to the RS485 module for responding to regulation signals, a voltage sampling and feedback module electrically connected between the output end and the input end of the output module, and a regulation output module electrically connected between the sampling input end of the voltage sampling and feedback module and the main control module; the power output module includes a variable voltage power output unit and a PWM control unit for controlling the output power of the variable voltage power output unit; the main dimmer further includes a 4G communication module for receiving the control signal of the mobile control terminal and communicatively connected to the main control module.

[0007] In some embodiments of the present disclosure, the dimming power supply further includes a cloud server for communication between the mobile control terminal and the main dimmer.

[0008] In some embodiments of the present disclosure, the variable voltage power output unit includes a transformer provided with a main winding, an auxiliary winding, and an output winding. The output end of the PWM control unit is electrically connected to the main winding correspondingly through a MOS tube, and the auxiliary winding is electrically connected to the power supply port of the PWM control unit correspondingly.

[0009] In some embodiments of the present disclosure, a voltage stabilization power supply unit for supplying power to the main control module is electrically connected to the output ends of the variable voltage power output units of the main dimmer and the sub-dimmers correspondingly.

[0010] In some embodiments of the present disclosure, a step-down power supply unit for supplying power to the 4G communication module is electrically connected to the output end of the variable voltage power output unit of the main dimmer correspondingly.

[0011] In some embodiments of the present disclosure, the main control module is a WiFi chip, and the main control module includes a storage unit for storing historical regulation data.

[0012] In some embodiments of the present disclosure, the regulation output module includes a plurality of capacitors for converting the regulation signal of the main control module into a DC signal.

[0013] In some embodiments of the present disclosure, the voltage sampling and feedback module includes a diode provided at its sampling input end, and the anode of the diode corresponds to the sampling input end of the voltage sampling and feedback module.

[0014] In some embodiments of the present disclosure, the voltage sampling feedback module includes an optocoupler isolation unit. The input end of the optocoupler isolation unit is electrically connected to the cathode of the diode through a three-terminal voltage regulator, and the output end of the optocoupler isolation unit is electrically connected to the PWM control unit correspondingly.

[0015] One or more technical solutions provided in the embodiments of the present application have any of the following technical effects or advantages:

[0016] The RS485 communication modules of each dimmer form a Modbus control network, and twisted pairs and RS485 communication are used between Modbus networking devices. Compared with the existing wireless networking, it can have higher stability and security, and is not easily interfered by the outside world; and the communication rate between the dimmers in the Modbus network is fast, so the synchronization of each dimmer in the network can be realized, and delay-free control can be achieved, so that the dimming effect has synchronization and consistency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the composition principle of a dimming power supply based on Modbus networking in an embodiment of the present application.

[0018] Figure 2 It is a schematic diagram of the composition principle of the main dimmer in an embodiment of the present application.

[0019] Figure 3 It is a circuit schematic diagram of the rectification and filtering module in an embodiment of the present application.

[0020] Figure 4 It is a circuit schematic diagram of the power output module in an embodiment of the present application.

[0021] Figure 5 It is a circuit schematic diagram of the voltage sampling feedback module in an embodiment of the present application.

[0022] Figure 6 It is a circuit schematic diagram of the regulation output module in an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The programs involved or relied on in the following embodiments are all conventional programs or simple programs in the technical field, and those skilled in the art can make conventional selections or adaptive adjustments according to specific application scenarios. The components involved in the following embodiments are all conventional commercially available products unless otherwise specified.

[0024] In order to better understand the technical solutions of the present application, the above technical solutions will be described in detail below in conjunction with the accompanying drawings of the specification and specific embodiments.

[0025] To solve the technical problems of high dimming cost and poor control reliability in the prior art, this example discloses a dimming power supply based on Modbus networking. See Figure 1 , which includes a mobile control terminal, a main dimmer wirelessly communicatively connected to the mobile control terminal, and a plurality of sub-dimmers RS485 communicatively connected to the main dimmer.

[0026] In this embodiment, the mobile control terminal is a smart phone, and control information is input and sent through the APP or applet installed on the smart phone. Among them, for the dimming power supply in this example to realize the transmission of control data from the mobile control terminal to the main dimmer, the dimming power supply further includes a cloud server. On the one hand, the cloud server interacts with the APP or applet of the mobile control terminal, and on the other hand, wirelessly sends the corresponding control signal to the main dimmer through the TCP communication protocol. The main dimmer then distributes the control instructions it receives to each sub-dimmer in the power supply through the RS485 communication method, that is, a Modbus network is formed between each sub-dimmer and the main dimmer, thereby realizing the control of the light sources respectively electrically connected to each dimmer. Similarly, each dimmer can also upload its control data to the cloud server through the above path for the mobile control terminal to obtain and view.

[0027] Among them, in some other embodiments, the dimming power supply does not include a cloud server, and its mobile control terminal can be directly communicatively connected to the main dimmer. Since the main dimmer includes a 4G communication module and an RS485 communication module; thus, the combination of the 4G communication module and the RS485 communication module realizes the gateway function. After the mobile control terminal establishes a connection with the gateway, the data of the 4G communication module is forwarded through the RS485 communication module, so as to perform control through the Modbus remote control network composed of the RS485 communication modules of each dimmer. Among them, the gateway composed of the combination of the 4G communication module and the RS485 communication module can send the control data sent by the mobile control terminal to all sub-dimmers in the network through the Modbus remote control network composed of the RS485 communication module. Each sub-dimmer resolves the control data sent by the mobile control end through the physical address, so as to realize the control function of each dimmer in the network. Since the Modbus networking uses twisted pair and RS485 communication, it can have higher stability and security compared with wireless networking, and the communication rate between each dimmer in the Modbus network is fast, ensuring synchronous and delay-free control of each dimmer in the network, so that the dimming effect has synchronism and consistency.

[0028] Specifically, the main dimmer and the sub-dimmer respectively include a rectifier filter module, a power output module, an RS485 module, a main control module, a voltage sampling feedback module, and a control output module; in addition, see Figure 2 , the main dimmer further includes a 4G communication module.

[0029] See Figure 3 , the rectification and filtering module is used to rectify and filter the mains power to obtain the required direct current. In this embodiment, the rectification and filtering module adopts a full-bridge rectification circuit composed of diodes D101, D102, D103, and D104, and after rectification, a DC voltage of about 310V is obtained by filtering with capacitor C101.

[0030] The power output module is used to further adjust and change the direct current converted by the rectification and filtering module, so as to control the light source connected thereto through power output control. In this embodiment, the power output module includes a PWM control unit and a variable voltage power output unit. Among them, the PWM control unit realizes the on-demand adjustment of the voltage by regulating the duty cycle, and the variable voltage power output unit is used to realize the regulated output of the specified voltage.

[0031] Specifically, see Figure 4 , in this embodiment, the PWM control unit of the power output module specifically adopts a PWM control chip with the model number OB2263. Its VDD power supply port is connected to the output of the rectification and filtering module through resistor R103 via port P1, and this power supply port is also grounded through filtering capacitor C103. Thus, at the moment of power-on startup, resistor R103 charges filtering capacitor C103. When the voltage at filtering capacitor C103 reaches the startup voltage of OB2263, the PWM control chip starts to work, and its GATA pin starts to output high-level pulses. Among them, its GATA pin is connected to the gate of MOS transistor Q101 through resistor R105, the drain of MOS transistor Q101 is connected to transformer T101 of the variable voltage power output unit. Transformer T101 includes a main winding N3, an auxiliary winding N2, and an output winding N1. Specifically, the drain of MOS transistor Q101 is connected to the main winding N3 of transformer T101. Thus, when the GATA pin of the PWM control chip outputs a high-level pulse, MOS transistor Q101 conducts, the current of the main winding N3 increases, and the energy storage of transformer T101 increases; when the GATA pin of the PWM control chip is turned off, a part of the energy storage of transformer T101 is unidirectionally rectified to C103 through the auxiliary winding N2 and diode D106, so as to realize the continuous power supply to the PWM control chip OB2263; another part is rectified into a DC voltage through the output winding N1 and large-current diode D107 as the power output, which is used to supply energy to the LED light source device, thus realizing the power output.

[0032] The power output module can output corresponding power as needed to control the brightness of the light source connected thereto. In order to obtain the regulation requirements so that the power output module can have corresponding responses, in this embodiment, the main dimmer and the sub-dimmer further include a main control module and an RS485 module. Among them, since the main dimmer also needs to communicate wirelessly with the mobile control terminal, the main dimmer further includes a 4G communication module, and this 4G communication module is communicatively connected to the main control module.

[0033] Specifically, in this embodiment, the main control module uses a WiFi chip, and the RS485 module communicates with the I / O port of this WiFi chip. At the same time, because a WiFi chip is used, the dimmer can perform WiFi communication through the mobile control terminal for emergency use. In addition, the main control module in this example further includes a storage unit for storing historical regulation data, so that when the dimmer is powered on again after a power failure, the WiFi chip can read the brightness value memorized inside the storage unit before the power failure, and thus output the PWM signal value corresponding to the corresponding brightness for brightness adjustment. In addition, the 4G communication module additionally provided in the main dimmer compared with the sub-dimmer is communicatively connected to the data interface of this WiFi chip to obtain the regulation signal sent by the mobile control terminal.

[0034] The WiFi chip of the main control module outputs PWM signals with different duty cycles corresponding to the regulation requirements. In order to enable the power output module to achieve corresponding responses and at the same time ensure corresponding reliability, in this embodiment, a voltage sampling feedback module is provided. This voltage sampling feedback module samples the output of the power output module and compares it with the output of the main control module, and adjusts the output of the power output module according to the comparison difference to achieve feedback closed-loop control.

[0035] See Figure 5 , the voltage sampling feedback module realizes voltage sampling of the output of the power output module through the P3 port connected to the output of the power output module. In order to judge whether the sampled voltage reaches the control requirements of the main control module, it needs to be compared with the output of the main control module. In this embodiment, the voltage sampling feedback module obtains the output of the main control module through the regulation output module connected to the P4 port. Specifically, see Figure 6 , the P5 port of the regulation output module is connected to the output of the main control module for transmitting the PWM regulation signal output by the WiFi chip of the main control module, and the P4 port of the regulation output module is connected to the voltage sampling feedback module for comparison with the sampled voltage.

[0036] Specifically, see Figure 5 and Figure 6, the voltage sampling feedback module includes diode D201, three-terminal regulator TL431, and optocoupler isolation unit U103; among them, the anode of diode D201 is connected to the sampling port P4 of the power output module; the input terminal of the optocoupler isolation unit is correspondingly electrically connected through the three-terminal regulator TL431, and its output terminal is correspondingly electrically connected to the PWM control unit. When the duty cycle of the PWM regulation signal output by the main control module WiFi chip is 0%, most of the current of the sampling voltage passing through resistor R205 flows to the main control module WiFi chip, and the current flowing to diode D201 is basically 0. Therefore, the voltage of resistor R208 is relatively small. At this time, for the circuit composed of resistors R202, R207, and R208 in series, the voltage divided by resistor R207 is relatively large. If the voltage on resistor R207 is greater than the conduction voltage of regulator TL431, which is 2.5V, then the 1st and 2nd pins of regulator TL431, that is, the cathode and anode, will conduct. Furthermore, the circuit where the input terminal of optocoupler isolation unit U103 is connected in series with resistor R204 forms a path to GND, the output terminal of optocoupler isolation unit U103 conducts, and the feedback signal is transmitted to the PWM control chip OB2263 through port P2. Then, the PWM control chip adjusts the corresponding output according to the feedback signal to form a closed-loop control; similarly, when the duty cycle of the PWM signal output by the main control module WiFi chip is 100%, most of the current of the sampling voltage passing through resistor R205 flows to diode D201, making the voltage divided by resistor R208 relatively large, and further making the voltage divided by resistor R207 relatively small. If the voltage of resistor R207 is less than the conduction voltage of regulator TL431, which is 2.5V, then the anode and cathode of regulator TL431 will not conduct, and the output terminal of optocoupler isolation unit U103 will not conduct either. This feedback signal is transmitted to the PWM control chip OB2263 through port P2, and the PWM control chip adjusts the corresponding output according to the feedback signal.

[0037] Thus, before the output voltage reaches the set value, the PWM duty cycle output by the PWM control chip OB2263 gradually increases, and the output voltage gradually rises; when the sampling voltage of the 3rd pin of regulator TL431 is higher than 2.5V, the current of regulator TL431 increases, which makes the current of the light-emitting diode inside optocoupler isolation unit U103 increase. Consequently, the output terminal current of the optocoupler isolation unit increases, and the voltage of the FB pin of the PWM control chip OB2263 becomes lower, causing the duty cycle of the PWM signal output by the PWM control chip OB2263 to decrease, and finally causing the output voltage to drop, completing the regulated output of the specified voltage. When the PWM signal of the main control module WiFi chip is adjusted between 0% and 100%, the corresponding output voltage is adjusted between 12.5V and 5V, thereby changing the brightness of the LED light source connected thereto.

[0038] In addition, for the convenience of providing the main control module with the required working voltage, in this example, a voltage stabilizing power supply unit is connected to the P3 port of the variable voltage power output unit. In this example, the low dropout linear voltage regulator chip BL9153-3.3 is used for the voltage stabilizing power supply unit. Similarly, since the main dimmer is equipped with a 4G communication module, in order to provide the 4G communication module with the required working voltage, in this embodiment, a step-down power supply unit is connected to the P3 port of the variable voltage power output unit, and the step-down voltage converter JW5033S is used for step-down conversion.

[0039] When this dimming power supply is in use, after entering the device control interface through a mobile control terminal such as the APP or applet of a smart phone, multiple gateway devices can be queried in the device list area. Clicking on any gateway device will enter the device operation interface within the gateway. The dimmers displayed on this interface belong to the same Modbus network. By checking the corresponding dimmer and dragging the dimming progress bar, the light source corresponding to the selected dimmer can be dimmed. At the same time, the mobile control terminal sends a control command through the network. After receiving the control command, the main dimmer sends the corresponding control command to the devices in the Modbus network through the RS485 module. After each dimmer obtains the corresponding command through physical address resolution, it performs a dimming operation.

[0040] Although some preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0041] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of its inventive concept. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these changes and modifications.

Claims

1. A dimming power supply based on Modbus networking, characterized in that: It includes a mobile control terminal, a main dimmer connected to the mobile control terminal by wireless communication, and a plurality of sub-dimmers connected to the main dimmer by RS485 communication; The main dimmer and the sub-dimmer respectively include a rectifier and filter module electrically connected to the mains, a power output module electrically connected to the rectifier and filter module, an RS485 module for Modbus networking, a main control module communicatively connected to the RS485 module for responding to a control signal, a voltage sampling and feedback module electrically connected between the output end and the input end of the output module, and a control output module electrically connected between the sampling input end of the voltage sampling and feedback module and the main control module; the power output module includes a transformer power output unit and a PWM control unit for controlling the output power of the transformer power output unit; The master dimmer also includes a 4G communication module for receiving a control signal from the mobile control terminal and communicating with the main control module.

2. The dimming power supply according to claim 1, characterized in that: It also includes a cloud server for communication between the mobile control terminal and the main dimmer.

3. The dimming power supply according to claim 1, characterized in that: The transformer power output unit includes a transformer having a main winding, an auxiliary winding and an output winding. The output end of the PWM control unit is electrically connected to the main winding via a MOS tube, and the auxiliary winding is electrically connected to a power port of the PWM control unit.

4. The dimming power supply according to claim 1, characterized in that: The output ends of the transformer power output units of the main dimmer and the sub-dimmer are electrically connected to voltage-stabilizing power supply units for supplying power to the main control module.

5. The dimming power supply according to claim 4, characterized in that: The output end of the transformer power output unit of the main dimmer is electrically connected to a step-down power supply unit for supplying power to the 4G communication module.

6. The dimming power supply according to claim 1, characterized in that: The main control module is a WiFi chip, and the main control module includes a storage unit for storing historical control data.

7. The dimming power supply according to claim 1, characterized in that: The control output module includes a plurality of capacitors for converting the control signal of the main control module into a DC signal.

8. The dimming power supply according to claim 1, characterized in that: The voltage sampling feedback module includes a diode arranged at its sampling input end, and the anode of the diode corresponds to the sampling input end of the voltage sampling feedback module.

9. The dimming power supply according to claim 8, characterized in that: The voltage sampling feedback module comprises an optocoupler isolation unit, the input end of the optocoupler isolation unit is electrically connected to the cathode of the diode via a three-terminal regulator, and the output end of the optocoupler isolation unit is electrically connected to the PWM control unit.

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