Patent Publication Number: US-2010127642-A1

Title: Cluster control device of street lamp circuits

Description:
FIELD OF THE INVENTION 
     The present invention relates to a control device for street lamps, and in particular to a cluster control device of street lamps. 
     BACKGROUND OF THE INVENTION 
     Conventionally, street lamps are grouped in different clusters for sectionized supply of electrical power. To meet the demand of saving energy and reducing power consumption, supply of electrical power to the street lamps in a street in time periods when less pedestrians, passer-bys, or vehicles moving through the street may adopt such a mode that the street lamps are lit every alternate ones. Lamp bulbs used in street lamps are of several types, including sodium vapor lamps, electrodeless lamps, semiconductor lamps, and light-emitting diode (LED) lamps, among which the LED lamps are most potential in replacing other types of street lamps. 
     SUMMARY OF THE INVENTION 
     However, sectionized power supply may lead to apparent dark zones in the lighting brightness of the street lamps, and in addition, timer controllers must be incorporated in the lamp circuit of a controlled lamp. This may cause undesired trouble in resuming the greatest brightness during a power consumption reduced period. Further, the centralized control for the wiring arrangement of this mode may require increased costs in constructing wiring ducts. 
     In addition, certain problems must be overcome before the LED street lamp can become prevailing. For example, in long-time illumination operation, the LED lamps not only consumes a great amount of electrical power, but also generates a great amount of heat, which often leads to damage and malfunctioning of the LED street lamps and also reduces the lighting efficiency of the street lamps, and may even cause total failure of the whole street lamp system due to the undesired excessively high temperature. 
     Thus, an objective of the present invention is to provide a cluster control device of street lamp circuits, which uses an existing power supply circuit of street lamps to perform both functions of communication and supply of electrical power, so that street lamps can be operated in various modes for being lit individually or in combination with other street lamps. 
     Another objective of the present invention is to provide a cluster control device of street lamp circuits, which performs control of all the street lamps of the street lamp circuits in a clustered manner for individually adjusting lighting mode of each street lamp so as to realize individual adjustment and setting for different types of street lamp. 
     The technical solution that the present invention adopts to overcome the above discussed problems comprises a plurality of control modules and at least one master controller. The control modules are respectively connected to a plurality of street lamps included in a power supply circuit. Each control module functions to control the respective street lamp in accordance with control parameters stored in a memory. The master controller is set in communication with each of the control modules to read and write control parameters stored in the memory of each control module. 
     With the technical solution adopted in the present invention, a power supply circuit for street lamps is expanded in the functions thereof so that the power supply circuit may also provide communication between a master controller and control modules for transmission of synchronous calibration signal, brightness control ratio, and control parameters so as to realize a communication mechanism for reading/writing and transmission of data. 
     Further, each street lamp is controlled by a dedicated control module, which may perform a control operation that provides the street lamp with different brightness at different periods of time in accordance with control parameters stored in a memory and may also allow the illuminance of all the street lamps to be increased/decreased at the same time, or making the brightness of a specific street lamp controlled in a manner different from other street lamps. For example, an LED street lamp can be controlled in respect of time period of lighting and ratio of brightness in accordance with heat generation of the LED lamp so as to extend the service life of the LED lamp. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be apparent to those skilled in the art by reading the following description of preferred embodiments thereof with reference to the drawings, in which: 
         FIG. 1  shows a system block diagram of a first embodiment in accordance with the present invention; 
         FIG. 2  shows a circuit diagram of a master controller; 
         FIG. 3  shows a circuit diagram of a control module; and 
         FIG. 4  shows a system block diagram of a second embodiment in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawings and in particular to  FIG. 1 , a cluster control device  100  is provided in accordance with the present invention for street lamp circuits. The cluster control device  100  comprises a power supply circuit C 1  that is connected to a plurality of street lamp circuits C 11 , C 12 , C 13 . Each of the street lamp circuits C 11 , C 12 , C 13  comprises a street lamp  1   a ,  1   b ,  1   c  and the power supply circuit C 1  transmits electrical power supplied from a power supply device  2  through a time switch  3  to each of the street lamps  1   a ,  1   b ,  1   c.    
     Each street lamp  1   a ,  1   b ,  1   c  is connected to a control module  5   a,    5   b,    5   c,  which is selectively set in communication with a master controller  4 . 
     Referring to  FIG. 2 , the master controller  4  comprises a central control circuit  41 , which is electrically connected to a power supplying/charging control circuit  42 , a communication power-feeding circuit  43 , a system conversion control circuit  44 , an audio decoding circuit  45 , an audio transmitter circuit  46 , a status displaying circuit  47 , an interface communication circuit  48 , and an input detection circuit  49 . 
     The central control circuit  41  comprises a central processing unit MCU 1 , a reference clock  411 , and a memory  412 . The reference clock  411  generates a reference time. The memory  412  stores cluster control parameters  413 . The cluster control parameters  413  store data including year-round sunrise/sunset time table, system malfunction records, initial system voltage/current, number of controlled control modules, brightness period and brightness ratio, reporting phone number, phone number for dialing connection for master control. 
     The power supplying/charging control circuit  42  comprises a power supplying/charging control unit  421  and a battery set  422  and stores the electrical power supplied from the power supply circuit C 1  in the battery set  422  to provide electrical power to the master controller  4  and to provide the current status of power supplying to the central processing unit MCU 1 . 
     The communication power-feeding circuit  43  comprises a voltage regulation unit  431 , a rectifier BR 1 , and couplers T 1 , T 2  and functions to supply electrical power to the control modules  5   a,    5   b,    5   c  at the time when the master controller  4  are in communication with the control modules  5   a,    5   b ,  5   c  and also to detect if communication is being performed or the line is busy for communication. 
     The system conversion control circuit  44  comprises four relays RY 1 , RY 2 , RY 3 , RY 8 , which are used to control switching between operations of the power supply circuit C 1  in accordance with the cluster control parameters  413  stored in the memory  412 . 
     The audio decoding circuit  45  comprises an audio decoding unit  451 , which applies an audio code transmitted from the control modules  5   a,    5   b,    5   c,  after being properly decoded by being coupled by a coupler T 4 , to the central processing unit MCU 1  for subsequent processing. The audio transmitter circuit  46  comprises an audio transmission unit  461  and an amplifier  462 , whereby when the central processing unit MCU 1  drives the relay RY 1  to have a relay contact RY 1   a  closed, an audio code is transmitted through a coupler T 3  to be received by the control modules  5   a,    5   b,    5   c.    
     The status displaying circuit  47  is controlled by an output from the central processing unit MCU 1  to display all sorts of status and control modes of the master controller  4 . The interface communication circuit  48  allows the master controller  4  to carry out data transmission with a main control facility  6  (see  FIG. 4 ) through the interface communication circuit  48 . The interface communication circuit  48  can be for example wireless GPRS communication circuit or wired RS485 communication circuit, the use of these communication circuits being dependent upon requirement of applications. 
     The input detection circuit  49  functions to retrieve external input signals to be processed by the central processing unit MCU 1 . In the instant embodiment, the external input signals are from a light detection element  491  and a hand-hole cover  492 . If desired, depending upon the applications used, the external input signals can be supplied by other sensors  493 . 
     Referring to  FIG. 3 , the control module  5   a  comprises a central control circuit  51 , which is connected to a power supplying/charging control circuit  52 , a line detection control circuit  53 , a system conversion control circuit  54 , an audio decoding circuit  55 , an audio transmitter circuit  56 , an input detection circuit  57 , and an alarm displaying circuit  58 . 
     The central control circuit  51  comprises a central processing unit MCU 2 , a reference clock  511 , and a memory  512 . The reference clock  511  generates a reference time, and can perform periodic remote synchronization calibration through the master controller  4 . The memory  512  stores control parameters  513 . The control parameters  513  store data including year-round sunrise/sunset time table, lamp type, lamp malfunction records, serial number of control module, brightness period and brightness ratio, and reporting phone number. 
     The power supplying/charging control circuit  52  comprises a power supplying/charging control unit  521  and a battery set  522  and stores the electrical power supplied from the power supply circuit C 1  in the battery set  522  to provide electrical power to the control module  5   a  and also to provide the current status of power supplying to the central processing unit MCU 2 . 
     The line detection control circuit  53  comprises rectifiers BR 2 , BR 3  for detecting if the power supply circuit C 1  is in a busy condition. The system conversion control circuit  54  comprises four relays RY 4 , RY 5 , RY 6 , RY 9 , which are used to control switching operation of the power supply circuit C 1  in accordance with the control parameters  513  stored in the memory  512 . 
     The audio decoding circuit  55  comprises an audio decoding unit  551 , which applies an audio code transmitted from the master controller  4  or other control modules  5   b,    5   c,  after being properly decoded by being coupled by a coupler T 6 , to the central processing unit MCU 2  for subsequent processing. The audio transmitter circuit  56  comprises an audio transmission unit  561  and an amplifier  562 , whereby when the central processing unit MCU 2  drives the relay RY 4  to have a relay control RY 4   a  occupying the line and also drives the relay RY 6  to have a relay contact RY 6   a  closed, an audio code is transmitted through a coupler T 5  to be applied to the power supply circuit C 1  for being received by the master controller  4  or the other control modules  5   b,    5   c.    
     The input detection circuit  57  functions to retrieve external input signals to be processed by the central processing unit MCU 2 . In the instant embodiment, the external input signals are from a light detection element  571  and a hand-hole cover  572 . If desired, depending upon the applications used, the external input signals can be supplied by other sensors  573 . The alarm displaying circuit  58  is driven by the central processing unit MCU 2  for displaying the operation condition of the control module  5   a  and alarms and for issuing different types of intermittent alarming signals. 
     Referring to  FIGS. 1 to 3 , in the instant embodiment, the street lamp  1   a  comprises a light-emitting diode (LED) lamp, which is composed of a lamp voltage regulation circuit  12 , a pulse width modulation (PWM) control circuit  13  connected to the lamp voltage regulation circuit  12 , and an LED array  14 . It is noted that the street lamp  1   a  can alternatively comprise a semiconductor lamp, a sodium vapor lamp, or an electrodeless lamp. When the cluster control device  100  is set in a lighting mode, the electrical power supplied from the power supply device  2  is transmitted through the time switch  3  and the power supply circuit C 1  to the street lamp  1   a . The PWM control circuit  13  is controlled by the control module  5  to adjust the illuminance provided by the LED array  14  of the street lamp  1   a.    
     The power supply circuit C 1  comprises a phase line L, a neutral line N, and a ground line G. When the cluster control device  100  is set in a communication mode, the master controller  4  drives the relay RY 2  to open relay contacts RY 2   a,  RY 2   b  so as to make open circuiting between the phase line L and the neutral line N and the time switch  3  and also drives the relay RY 3  to close relay contacts RY 3   a,  RY 3   b  so as to make closed circuiting between the phase line L and the neutral line N and the master controller  4 ; and the control module  5   a  drives the relay RY 5  to switch relay contacts RY 5   a,  RY 5   b  so as to make closed circuiting between the control module  5   a  and the phase line L and the neutral line N to thereby constitute a first communication transmission path, whereby the master controller  4  is in communication with the control module  5   a,    5   b,    5   c  through the power supply circuit C 1  and the master controller  4  is allowed to read/write data of the control parameters  513  stored in the memory  512  of the control module  5   a  according to the cluster control parameters  413 . 
     Further, the master controller  4  also drives the relay RY 8  to switch relay contacts RY 8   a,  RY 8   b  to selectively use the phase line L or the neutral line N, and the ground line G; and the control module  5   a  drives the relay RY 9  to switch relay contacts RY 9   a,  RY 9   b  in order to selectively use the phase line L or the neutral line N, and the ground line G to thereby constitute a second communication transmission path. 
     Although in the instant embodiment, the master controller  4  uses the power supply circuit C 1  to establish communication with each control module  5   a ,  5   b,    5   c,  the communication of the master controller  4  with the control modules  5   a ,  5   b,    5   c  can be alternatively established in a wireless manner and for reading/writing the control parameters  413  stored in the memory  412  of the master controller  4 . 
       FIG. 4  shows a second embodiment of a cluster control device constructed in accordance with the present invention, generally designated at  100   a  for distinction, which possess a structure that is similar to the cluster control device  100  of the first embodiment discussed previously, so that similar components are designated with the same reference numerals for correspondence and simplicity. 
     In the second embodiment, the cluster control device  100   a  further comprises a power supply circuit C 2  that is electrically connected to a plurality of street lamp circuits C 21 , C 22 , C 23 , each comprising a street lamp  1   d ,  1   e ,  1   f . The power supply circuit C 2  transmits electrical power supplied from a power supply device  2   a,  through a time switch  3   a,  to each of the street lamps  1   d ,  1   e ,  1   f . Each street lamp  1   d ,  1   e , if is connected to a control module  5   d,    5   e,    5   f,  which is selectively set in communication a the master controller  4   a.    
     The second embodiment offers a feature that the master controllers  4 ,  4   a  use the respective interface communication circuit  48  (see  FIG. 2 ) to connect to the main control facility  6  through a transmission interface  61 , thereby forming a nest-architecture system. In this way, the main control facility  6  is allowed to carry out clustered control of all the control modules  5   a,    5   b,    5   c,    5   d,    5   e,    5   f  through the master controllers  4 ,  4   a.    
     Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.