WO2013040736A1

WO2013040736A1 - Dc high voltage power supply led street lamp system and realization method thereof

Info

Publication number: WO2013040736A1
Application number: PCT/CN2011/002008
Authority: WO
Inventors: 张雅萍; 李旭亮
Original assignee: 东莞勤上光电股份有限公司
Priority date: 2011-09-19
Filing date: 2011-11-30
Publication date: 2013-03-28

Abstract

The present invention relates to a DC high voltage power supply LED street lamp system, comprising: a central DC power cabinet for outputting different high voltage signals; and an LED street lamp connected to the central DC power cabinet via a wire to receive the different high voltage signals and show different display states according to the different high voltage signals. The present invention features an integrated power supply and control, thus greatly saving setup and maintenance costs for an LED light system, and further improving the overall life and reliability.

Description

TECHNICAL FIELD The present invention relates to an LED lighting power supply system, and in particular to a DC high voltage power supply LED street light system and an implementation method thereof. BACKGROUND OF THE INVENTION Compared with conventional street lamps, LED street lamps have the advantages of long service life and energy saving. Previous LED street lights are powered by alternating current (AC). Each LED street light requires at least one switching power supply for converting AC to direct current (DC) in order for the LED street light to function properly. However, due to the short life and frequent damage of the power supply, this brings maintenance problems to the LED street lamp, which indirectly affects the service life of the LED street lamp.

DC high-voltage power supply, that is, in the form of centralized power supply, directly delivers 250V high-voltage direct current to the LED street light, and the LED street light does not need to be equipped with a separate switching power supply. So far, there has not been a control method specifically for this DC high voltage power supply LED street light. When it is necessary to control such an LED street lamp, only a method for the AC-powered LED street lamp can be used, and a control system is added outside the street lamp power supply system, which requires installing a signal receiving device on each LED street lamp. And a device that centrally controls these signal receiving and executing devices. This type of approach creates an increase in labor and material costs, and in the future maintenance, it is also necessary to put maintenance into these devices. In addition, China invented "LED Street Light Controller", application number 200910105774.X, which discloses an LED street light controller that uses General Packet Radio Service (GPRS) and ZigBee wireless communication to transmit data. LED street light remote control, it is also a kind of independent control system and network. SUMMARY OF THE INVENTION The technical problem to be solved by the present invention is to provide an LED street lamp and a control device that does not require a dedicated line and a signal receiving device to receive a control signal carried on a DC high voltage power line.

The invention provides a DC high voltage power supply LED street lamp system, which comprises: a central DC power supply rejection for outputting different high voltage signals;

The LED street lamp is connected to the central DC power supply through a wire for receiving different high voltage signals, and displaying different display states according to different high voltage signals.

Further, the different high voltage signals include a first high voltage signal and a second high voltage signal, and the duration of the first high voltage signal rejected by the central DC power source is different from the duration of the second high voltage signal rejected by the central DC power source. .

Further, the different high voltage signal includes a first high voltage signal, a first high voltage to a second high voltage linear change signal, a second high voltage signal, and a second high voltage to a first high voltage linear change signal, the first high voltage signal, The durations of the first high voltage to the second high voltage linear change signal, the second high voltage signal, and the second high voltage to the first high voltage linear change signal are not completely the same. Further, the central DC power supply machine includes a main control chip, a digital-to-analog conversion module, and a power supply module that are electrically connected in sequence.

Further, the LED street lamp comprises a voltage conversion module, an analog-to-digital conversion module, a single-chip microcomputer, a constant current circuit and an LED light source which are electrically connected in sequence, wherein the voltage conversion circuit converts the high-voltage analog signal transmitted from the electric wire into a low-voltage analog signal, The low-voltage analog signal is sent to the analog-to-digital conversion module, and the analog-to-digital conversion module extracts the analog signal through analog-to-digital sampling, and converts the analog signal into a digital signal, which is sent to the single-chip microcomputer, and the single-chip microcomputer analyzes the digital signal, and then drives the constant signal. The flow circuit controls the display state of the LED light source.

The invention provides a method for realizing a DC high voltage power supply LED street lamp system, which comprises:

Rejecting different high voltage signals through the central DC power supply;

The LED street light receives different high voltage signals that the central DC power supply refuses to output, and displays different display states according to different high voltage signals.

Further, the different high voltage signal includes a first high voltage signal, a first high voltage to a second high voltage linear change signal, a second high voltage signal, and a second high voltage to a first high voltage linear change signal, the first high voltage signal, The durations of the first high voltage to the second high voltage linear change signal, the second high voltage signal, and the second high voltage to the first high voltage linear change signal are not completely the same. Further, the LED street lamp comprises a voltage conversion module, an analog-to-digital conversion module, a single-chip microcomputer, a constant current circuit and an LED light source which are electrically connected in sequence, wherein the voltage conversion circuit converts the high-voltage analog signal transmitted from the electric wire into a low-voltage analog signal, The low-voltage analog signal is sent to the analog-to-digital conversion module, and the analog-to-digital conversion module extracts the analog signal through analog-to-digital sampling, and converts the analog signal into a digital signal, which is sent to the single-chip microcomputer, and the single-chip microcomputer analyzes the digital signal, and then drives the constant signal. The flow circuit controls the display state of the LED light source.

Further, the central DC power source is mutually connected to the LED street lamp through a connection structure of wires of the bus or the star network.

Compared with the prior art, the present invention controls the power supply and display state of the LED street lamp by applying different high-voltage signals, and has the characteristics of power supply and control integration, greatly saving the new construction and maintenance cost of the LED lighting system, and further improving the overall life. And reliability. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be further described in detail below with reference to the drawings and specific embodiments. 1 is a schematic diagram of an application system architecture of a specific embodiment of the present invention;

2 is a schematic diagram of a control flow corresponding to the LED street lamp system shown in FIG. 1; FIG. 3 is a timing diagram of an output electrical signal of the DAC module in FIG.

4 is a timing diagram of the output electrical signal of the power module of FIG. 1;

FIG. 5 is a schematic diagram of an internal electrical structure of a specific embodiment of the present invention; FIG.

6 is a schematic diagram of timings of acquiring an electrical signal by the single chip microcomputer of FIG. 5;

7 is a schematic diagram of the single chip of FIG. 5 processing an electrical signal according to a state machine model; FIG. 8 is a schematic diagram of an internal electrical structure of a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1 , an application system of an LED street lamp to which the specific embodiment of the present invention is applied includes a central DC power supply rejection, a plurality of DC-powered LED street lamps, and a wire connecting the central DC power supply to the DC-powered LED street lamp. among them:

1. The central DC power supply rejects: the controller and at least one power module;

2. DC power supply LED street light includes: LED light source, voltage conversion circuit, analog-to-digital conversion (ADC) module, single-chip microcomputer, constant current circuit;

3. Wire: Directly use the existing AC wire to facilitate the transformation of street lamps. The central DC power source is mutually connected to the LED street lamp through a connection structure of a bus or a star network wire. Further, the controller of the central DC power supply rejection includes: an instruction receiving device, a main control chip (MCU), and a digital to analog conversion (DAC) module. Its working principle is:

The instruction receiving device is configured to receive an external dimming command and send the command to the MCU; the MCU analyzes and processes the dimming command, obtains dimming command information, and sends the dimming command information to the DAC module, and the DAC module sets the dimming command information Converted into an analog signal sent to each power module, the power module will make its own output change voltage at a predetermined frequency (with analog signal) according to the analog signal received from the DAC module, and the voltage with the analog signal will be supplied through the wire. It is delivered to each DC-powered LED street light. DC-powered LED street light: The voltage conversion circuit converts the analog signal transmitted from the wire from a high-voltage state to a low-voltage state. It also converts the high-voltage analog signal transmitted from the wire into a low-voltage analog signal, which is then sent to the ADC module, and the ADC module is sampled by AD. The analog signal is extracted, and the signal is converted into a digital signal and sent to the single chip microcomputer, and the single chip computer analyzes the digital signal to control the constant current circuit; the ADC module is also called a voltage sampling module.

The instruction receiving device, the main control chip (MCU), and the digital-to-analog conversion (DAC) module, as shown in FIG. 2, the LED street lamp system control signal transmission receiving method according to the embodiment of the present invention, the specific process includes the following steps:

301) power on begins;

302) The MCU control power module rejected by the central DC power supply is outputted by DC250V;

303) judging whether an external dimming instruction that the instruction receiving device forwards to the MCU through the serial port is received? Go to the next step, otherwise return to step 302);

304) The MCU extracts the external dimming command, processes it in bytes, sends the data to the DAC module according to the receiving format of the DAC module, and causes the DAC module to output an analog signal as shown in FIG. 3 to the power module.

among them,

T0>1.5P, tl=0.6P+200mP, t2=0.5P+200mP, t3=0.5P+200mP, t4=1.5P+200mP

Note: P is a unit of time, with a typical value of 1P = 1 second. T0, tl, t2, t3, and t4 represent different time periods, respectively. In this way, when the MCU outputs a control signal to the power module, the DAC module sequentially outputs the following voltage values: The DAC module first outputs a voltage of 5V, and the duration is t0; the DAC module outputs an output from 5V to 4.4V. The time varies linearly, the time required for this process is tl; the DAC module re-outputs the duration of t0, the voltage is 4.4V (4.4V is low voltage, and the low voltage duration is t2 indicates transmission) The data is binary number 0, the low voltage duration is t4, indicating that the data to be transmitted is a binary number 1); the DAC module outputs a voltage that varies linearly from 4.4V to 5V over time, this time is tl; .... The DAC module outputs 6 low voltages of 4.4V with a duration of t2 according to this rule, and then outputs 2 low voltages of 4.4V with a duration of _t 4 according to the same rule; the DAC module re-outputs from 4.4V to 5V. The continuously changing voltage, and after the voltage rises to 5V, outputs a high voltage of 5V for a duration of t0. At this point, the DAC module has transferred one byte of data (8 data bits) to the power module. If the MCU of the controller determines that the command signal has not been sent yet, the next byte will be transmitted as described above. Otherwise, the controller's MCU will let the DAC module continue to output 5V.

(Note: The waveform shown in Figure 3 indicates that the data to be transmitted to the power module by the MCU of the controller is hexadecimal 0x03, which is the binary number 0000 0011. In actual application, the MCU of the controller will be based on the data to be transmitted. To determine the number and order of '0' and T during transmission to determine the duration of the 4.4V low voltage, t2 and t4.

305) When receiving the signal output by the DAC module, the power module changes its own output voltage at the same time, and the output voltage of the power module is proportional to the output voltage of the DAC module. The 5V voltage output by the DAC module corresponds to the output voltage of the power module. For 250V, the 4.4V voltage output from the DAC module corresponds to the output voltage of the power module is 220 V, and the voltage is transmitted to the LED street lamp through the wire, as shown in Figure 4.

306) The voltage conversion circuit of the LED street lamp first converts the DC220V-DC250V high-voltage signal received from the power module into a 2.7V-3.3V low-voltage signal, and then delivers it to the ADC module for processing. The ADC module adopts timing sampling mode, and the sampling period is T. Converting the collected analog signal into a digital signal and handing it to the MCU for processing. After processing the specified number of data bytes according to the convention, the MCU operates the LED light source module by operating the constant current driving circuit to complete the signal receiving. Perform the operation. As shown in FIG. 5, an LED street lamp according to a first embodiment of the present invention includes a voltage conversion circuit, an ADC module, a single chip microcomputer, a constant current circuit, and an LED light source. The voltage conversion circuit and the central DC power source are electrically connected by wires. Its working principle is:

The voltage conversion circuit of the LED street lamp first converts the DC220V-DC250V high-voltage signal received from the power module rejected by the central DC power supply into a 2.7V-3.3V low-voltage signal, and then delivers it to the ADC module for processing, and the ADC module adopts a timing sampling method. The sampling period is T, and the collected analog signal is converted into a digital signal and sent to the single-chip microcomputer for processing. The single-chip microcomputer processes according to the convention: the LED street lamp is powered on, and the voltage detected by the ADC module is high level. Therefore, the single-chip microcomputer sets signal= l , signal is a Boolean variable, used to identify whether the voltage value collected by the microcontroller in the ADC module is low state or high state. The ADC module collects the M voltage value and gives it to the MCU (M>20, which is an integer variable). The MCU sorts the M voltage values from small to large, and removes 4 maximum and 4 minimum values. The average value of the lower (M-8) voltage values is stored in the array VOL[0], the array VOL is a one-dimensional array of length 4, which is used to store the average voltage value of the microcontroller during processing. According to this rule, the MCU obtains three average voltage values and stores them in VOL[l], VOL[2] and VOL[3].

After one sampling period T, the MCU makes VOL[0]=VOL[1], VOL[l]=VOL[2], VOL[2]=VOL[3], and the ADC module collects M voltage values again. For the single-chip microcomputer, the single-chip microcomputer obtains the average value of these voltages in the above manner and stores it in the array variable VOL[3]. The microcontroller updates the value of the VOL array in this way every 1 sample period. And compare these four values: If the difference between the four elements of the array VOL is within the error range, the MCU determines that it is "voltage steady state"; if VOL[0]-VOL[l]>Differ, VOL[ l]-VOL[2]>Differ,

VOL[2]-VOL[3]>Differ (The value of Differ depends on the specific tl time value), and the MCU determines it as "voltage falling edge state". At this time, set the signal flag Signal-Fat=0. Signal—Fat is a temporary variable set by the MCU to identify signal level changes; if VOL[l]-VOL[0]>Differ, VOL[2]-VOL[l]>Differ, VOL[3]-VOL[ 2]>Differ, the MCU determines the "voltage rising edge state" and sets the signal flag Signal_Fatmark=l.

In the above process, the value of the default signal is 1 when the microcontroller is powered on, and then the microcontroller will determine the value of signal according to the "voltage steady state", "voltage falling edge state" and "voltage rising edge state". If the MCU determines that it is "voltage steady state", then the value of Signal-Flag is 0, indicating that the voltage steady state has just passed a voltage falling edge. Therefore, the MCU determines that signal=0; if the MCU determines that the voltage is stable In the state, the value of siganl_flag is 1, indicating that the voltage plateau is just after a voltage. The rising edge, therefore, the microcontroller determines signal=l. According to the 0 or 1 state of signal, the MCU can get the waveform shown in Figure 6.

In the following process, the MCU uses the state machine idea based on the 0 or 1 state of the signal to finally analyze the control signal:

When the MCU is powered on, the default siganl=l, state=l, state is a variable set by the MCU to identify the steps in the signal analysis process. As shown in Figure 7, when the microcontroller detects that siganl is 0 from state=l, and the duration of state 1 meets the requirement, then state=2 and clear the data buffer; when the microcontroller detects signal from state=2, it is 1 , then state=3, at this time, the MCU will judge whether it is data bit 0 or data bit 1 according to the duration of state 2, and store it in the data buffer; the MCU judges the duration of state 2 according to this law, and obtains the data bit. When the program in the microcontroller reaches the 8th state 2, if siganl=l is detected, the state 4 is entered. The duration of state 4 is then tracked. When this time exceeds a certain value, it indicates that the data byte has been transferred and the microcontroller processes the byte.

After processing the specified number of data bytes according to the above rules, the single chip microcomputer controls the LED light source by operating the constant current circuit to complete the operation after the signal is received.

The LED street lamp of the invention can also output "0" or "1" after being processed according to the corresponding voltage change characteristics at the receiving end according to other agreed voltage variation rules on the electric wire. As shown in FIG. 8, the LED street lamp of the second embodiment of the present invention includes a voltage conversion circuit, an ADC module, a single chip microcomputer, a PWM dimmer, a constant current circuit, and an LED light source. The voltage conversion circuit of the LED street lamp first converts the DC220V-DC250V high-voltage signal received from the power module into a 2.7V-3.3V low-voltage signal, and then delivers it to the ADC module for processing. The ADC module adopts the timing sampling method, and the sampling period is T, The collected analog signal is converted into a digital signal and sent to the single-chip microcomputer for processing. The single-chip microcomputer sends the dimming signal to the PWM dimmer after being parsed according to the agreed law; the constant current circuit drives the LED light source according to the PWM dimmer output control signal. Compared with the prior art, the present invention controls the power supply and display state of the LED street lamp by applying different high-voltage signals, and has the characteristics of power supply and control integration, greatly saving the new construction and maintenance cost of the LED lighting system, and further improving the overall life. And reliability.

Claims

Claim

1. A DC high voltage power supply LED street lamp system, comprising: a central DC power supply rejection for outputting different high voltage signals;

2 . The DC high voltage power supply LED street lamp system according to claim 1 , wherein the different high voltage signals comprise a first high voltage signal and a second high voltage signal, and the first high voltage signal rejected by the central DC power source The duration of the second high voltage signal that is rejected by the central DC power supply is different.

3 . The DC high voltage power supply LED street lamp system according to claim 1 , wherein the different high voltage signals comprise a first high voltage signal, a first high voltage to a second high voltage linear change signal, a second high voltage signal, And a second high voltage to the first high voltage linear change signal, the duration of the first high voltage signal, the first high voltage to the second high voltage linear change signal, the second high voltage signal, and the second high voltage to the first high voltage linear change signal are not It's exactly the same.

The DC high-voltage power supply LED street lamp system according to claim 1, wherein the central DC power supply device comprises a main control chip, a digital-to-analog conversion module and a power supply module that are electrically connected in sequence.

5 . The DC high voltage power supply LED street lamp system according to claim 1 , wherein the LED street lamp comprises a voltage conversion module, an analog to digital conversion module, a single chip microcomputer, a constant current circuit and an LED light source, which are electrically connected in sequence, wherein The voltage conversion circuit converts the high voltage analog signal transmitted from the wire into a low voltage analog signal, and then sends the low voltage analog signal to the analog to digital conversion module, and the analog to digital conversion module extracts the analog signal through analog to digital sampling, and converts the analog signal. The digital signal is sent to the single chip microcomputer, and the single chip computer analyzes the digital signal, and drives the constant current circuit to control the display state of the LED light source.

6. A method for realizing a DC high voltage power supply LED street lamp system, characterized in that:

Rejecting different high voltage signals through the central DC power supply;

The method for realizing a DC high voltage power supply LED street lamp system according to claim 6, wherein the different high voltage signals comprise a first high voltage signal and a second high voltage signal, and the central DC power source rejects the output. The duration of a high voltage signal is different from the duration of the second high voltage signal rejected by the central DC power source.

The method for realizing a DC high voltage power supply LED street lamp system according to claim 6, wherein the different high voltage signals comprise a first high voltage signal, a first high voltage to a second high voltage linear change signal, and a second a high voltage signal, and a second high voltage to a first high voltage linear change signal, the first high voltage signal, the first high voltage to the second high voltage linear change The duration of the second signal, the second high voltage signal, and the second high voltage to the first high voltage linear change signal are not exactly the same.

The method for realizing a DC high voltage power supply LED street lamp system according to claim 6, wherein the LED street lamp comprises a voltage conversion module, an analog to digital conversion module, a single chip microcomputer, a constant current circuit and an LED electrically connected in sequence. a light source, wherein the voltage conversion circuit converts the high voltage analog signal transmitted from the wire into a low voltage analog signal, and then sends the low voltage analog signal to the analog to digital conversion module, and the analog to digital conversion module extracts the analog signal through analog to digital sampling, and The analog signal is converted into a digital signal and sent to the single chip microcomputer. After the single chip computer analyzes the digital signal, the constant current circuit is driven to control the display state of the LED light source.

The method for realizing a DC high-voltage power supply LED street lamp system according to claim 6, wherein the central DC power supply refuses to communicate with the LED street lamp through a bus or a star network connection structure. connection.