A kind of two-conductor line fire-fighting public address system for having fault alarmTechnical field
The present invention relates to emergency broadcase system, especially a kind of two-conductor line fire-fighting public address system for having fault alarm.
Background technology
According to the national standard of fire broadcast, the totally different voltage letter of 3 kinds of characteristics is actually applied and transmitted to this systemNumber.
The first is audio signal.This is a kind of powerful signal, is generated by power amplifier and is exported, to driveOne or more speakers.Its instantaneous power, may be from tens watts to thousands of watts according to needs.Frequency range can cover from80Hz to 20KHz.Audio signal is to belong to the random signal of multifrequency mixing in itself, and either all present can not be pre- for power or frequencyThe characteristic of survey.
Second of signal is digital communication signal.It is primarily used to whether reporting system component breaks down.It is thisThe transmission of signal may be intermittent, but the characteristic of digital signal is necessarily abided by transmission every time.First, it is small-power letterNumber, it exports in milliwatt range.The power of audio signal at least decades of times bigger than its power in general is to tens thousand of times.
The third is DC power supply.It is a fixed DC voltage, does not carry any signal.Its existing main meshBe for generate digital signal circuit DC power supply is provided.The number of loudspeakers serviced according to it is different, what it was providedPower is from several watts to tens watt, 1 to 3 order of magnitude smaller than audio power.This 3 kinds of signals, either on power, in frequency,On voltage, there is huge difference；So any intention makes them co-exist on the circuit that same two-conductor line is formed, and energyEnough allow each, a other separated application, do not interfered by other 2 signals, be a kind of exceedingly difficult attempt.
By currently there are emergency broadcase system for, in addition to audio quality is usually in close to minimum standard shapeOutside state；For the rigid requirement of real-time (the being less than 100 seconds) alarm of failure, it is often necessary to outside audio output two-conductor line, then additionallyIt is additional to pass through detection using 2 to 4 conducting wires.
For traditional public address system as shown in Fig. 1 circuit structure diagrams, traditional public address system includes source of sound 101,Source of sound connects power amplifier 102, and power amplifier 102 connects two-conductor line circuit 104, and two-conductor line circuit 104 passes through electricity in parallel105 matching connection transformer 106 of road and loud speaker 107, two-conductor line circuit 104 is equipped with to be connected with 102 output terminal of power amplifierAfter the output signal ingoing power amplifier 102 of source of sound 101, it is defeated to be amplified as required power for the output transformer 103 connectGo out the primary to output transformer 103.Here, power amplifier 102 is the power amplifier for belonging to AB classes or C classes.
Output transformer 103 is the voltage boosting device of a power match.According to general international standard, transformer is exported103 secondary output voltage is divided into two kinds of 70V p-p and 100V p-p peak-to-peak values.Fire broadcast also has equipment to use 120V p-P is as output voltage.
It is the needs because of 104 resistors match of two-conductor line circuit using the reason of high voltage.First, two-conductor line circuit 104Length be likely to be breached 100 meters or longer.In order to cost-effective, the conductor resistance generally selected is mostly in every meter of 0.1ohm range.100 meters of circuit (200 meters of total length) just generates the impedance of 20ohm.According to Ohm laws, the electric current per 1Amp is returned by 100 metersRoad can cause the voltage drop of 20V.So high voltage conveying is taken just to become the scheme that must be used.
The promotion power of each loud speaker 107 is inputted by parallel circuit 105 and matching transformer 106.It is common to raise one's voiceThe impedance of device 107 is 2,4,8,16ohm.By 6 watts of power, impedance 4ohm loud speaker 107 for, it spike driving voltage reasonIt can be calculated by value as follows：
For W=V2/R here, W is power=6W, V is spike driving voltage, and R is impedance=4ohm, obtains V=4.9V.
So the theoretical value 100V of the primary input voltage of matching transformer 106, the theoretical value of secondary output voltage4.9V.According to this data, best matching transformer 106 can be designed.If the output power of power amplifier 102 is 240Watt, then theoretically this public address system can install up to 40 6 watts of loud speaker 107.
Fig. 2 is the circuit structure diagram of another traditional public address system.It is a conventional high voltage broadcast system, is adoptedUse D-type power amplifier.System in the structure and figure one of this system is essentially identical；Only difference is that it is omittedExport transformer 103.This is because D-type power amplifier have direct output HIGH voltage ability, can directly export 70V orThe peak voltage of 100V.So the output transformer 103 with boost function can be saved, but if there is special requirement, noIt excludes to add in output transformer 103.
Above common public address system does not have fault alarm demand, they only use two-conductor line circuit.If necessary to riseFor grade for fire broadcast system, existing equipment just needs additional Fabric lines in the market for use, increases considerably constructional difficulties.
Invention content
The purpose of the present invention is to solve defects of the existing technology, provide a kind of two-conductor line for having fault alarm and disappearAnti- public address system.
To achieve these goals, the technical solution adopted by the present invention is：
A kind of two-conductor line fire-fighting public address system for having fault alarm, including source of sound, source of sound connection power amplifier, work(Rate amplifier connection two-conductor line circuit, two-conductor line circuit are returned by parallel circuit matching connection transformer and loud speaker, two-conductor lineIsolation capacitance is inserted into road close to output position resolver, and isolation capacitance provides the channel of AC signal for two-conductor line circuit, togetherWhen block direct current pass through, cause direct current interruption；
DC power supply is connected on two-conductor line circuit, the both ends of isolation capacitance connect the anode and cathode of DC power supply respectively,DC power supply connects and composes DC loop with two-conductor line circuit；
Fault alarm unit and branch's isolation capacitance are installed, fault alarm unit is primary with matching transformer on parallel circuitCoil, the current input terminal and output terminal of the both ends difference connecting fault alarm unit of branch's isolation capacitance.
Further, power amplifier of the power amplifier for AB classes or C classes, two-conductor line circuit are equipped with and are put with powerThe output transformer of big device output terminal connection.
Further, the power amplifier is D-type power amplifier, the endpoint in power amplifier input two-conductor line circuit itBetween installation isolation inductance；
This isolation inductance is unlikely to puncture D class power amplifications by the direct current channel direct current of theoretically zero impedanceDevice, the node in isolation D-type power amplifier input two-conductor line circuit.If there is special requirement, output transformer still can be usedSubstitute isolation inductance.
Further, the fault alarm unit is by DC power supplier, micro-control unit, load monitoring module, channel radioInterrogate module composition；
DC power supplier ensures numberical range of the stable operating voltage in a design of fault alarm unit；
Micro-control unit controls load monitoring module continues to monitor parallel circuit, matching transformer, loud speaker；
Load monitoring module judges whether loud speaker and its connection circuit work normally by monitoring the load of loud speaker.
Communication module can there are two types of select：Wireless communication module and wire communication module；Correspond respectively to following nothingsLine traffic control order circuit and wire communication control loop.
Further, the design in two-conductor line circuit connection communication control circuit can there are two types of：Wireless control order circuit andWired communication control circuit.
Wireless control order circuit is the system controller by being connected with each other, fault message wireless collector, antenna composition,Antenna is connect by wireless communication channel with the aerial signal of wireless fault alarm unit, and system controller is connect with source of sound.
Wired communication control circuit is the system controller by being connected with each other, signal modem, communication signal matchingTransformer is formed.Modulated communication signal frequency is far above audio signal, is striden by communication signal matching transformer doubleConducting wire is communicated by the demodulation function and micro-control unit of wire communication module.The modulated signal replied from micro-control unit, warpAfter signal modem demodulation, appropriate reaction is made in input system control.
Further, the source of sound is digital audio-frequency player or analogue audio frequency player or real-time audio player.
Further, the parallel circuit is multiple.
Further, the load monitoring module is a kind of electromagnetism sensing module such as Hall (Hall effect) monitoring elementOr other current measurement devices.
Further, the wireless communication module is serial for IEEE802.11, Zigbee, bluetooth module etc..It can also selectUsing ISM band such as：433MHz, 902MHz etc., and the customized communications protocol of adapted, ensure wireless fault alarm unit canBy property and stability.Wireless communication module is connect with antenna, provides wireless transmitting function.
Further, the wire communication module, passes through internal communication Signal Matching transformer and two-conductor line communication controlCircuit connects.The communication signal generated by micro-control unit, the modem in input module.After ovennodulation, by logicalIt interrogates Signal Matching transformer and flows into two-conductor line communication control circuit.The control signal flowed into from two-conductor line communication control circuit, leads toCross the modem that communication signal matching transformer flows into module.Signal after demodulated inputs micro-control unit.
Beneficial effects of the present invention are：The audible communication circuit of the two-conductor line fire-fighting public address system, direct current supply are returnedRoad and wirelessly or non-wirelessly order circuit can effectively and be deposited.And with two-conductor line circuit form, at the same meet fire-fighting with it is public wideThe double standards broadcast.
Description of the drawings
Fig. 1 is the circuit structure diagram using AB classes and traditional public address system of C class power amplifiers；
Fig. 2 is the circuit structure diagram using traditional public address system of D class power amplifiers；
Fig. 3 uses AB classes and the two-conductor line public broadcasting of C class power amplifiers and fault alarm hybrid system after being improved for the present inventionCircuit structure diagram；
Fig. 4 is using the two-conductor line public broadcasting of D class power amplifiers and the circuit of fault alarm hybrid system after the present invention improvesStructure chart；
Fig. 5 is the interior design figure of wireless fault alarm unit of the present invention；
Fig. 6 is three circuit public broadcasting of two-conductor line of the present invention and wireless fault alarm hybrid system schematic diagram；
Fig. 7 is three circuit public broadcasting of two-conductor line of the present invention and fault wired alarm hybrid system schematic diagram；
Fig. 8 is the interior design figure of wireless fault alarm unit of the present invention；
Fig. 9 is wire communication module design figure of the present invention；
Figure 10 is the building schematic diagram that broadcast system is installed in second floor in case study on implementation of the present invention；
Figure 11 is the building schematic diagram that broadcast system is installed in Stall in case study on implementation of the present invention.
Specific embodiment
The invention will be further described with reference to the accompanying drawings and detailed description.
As shown in Figures 3 to 6, the two-conductor line fire-fighting public address system using wireless telecommunications as fault alarm, Fig. 3 areBased on the conventional solution of Fig. 1, addition innovative circuits completion is undertaken, while provide audio broadcasting the present invention with two-conductor lineFunction, component wireless fault alarm function and the completing the DC power supply needed for warning function of the task.
Audio broadcasting first approaches output transformer in two-conductor line circuit 104 still based on the structure of Fig. 1Isolation capacitance 202 is inserted into 103 positions.The main function of this isolation capacitance 202 is to provide AC signal for two-conductor line circuit 104The channel of (audio broadcast signal)；Direct current is blocked to pass through simultaneously, cause direct current interruption.Then at the both ends of isolation capacitance 202, divideNot Lian Jie DC power supply 201 export, for endpoint 205 for just, endpoint 206 is negative.It is this to arrange so that two-conductor line circuit 104 is able to togetherMono- ac circuit of Shi Yunhang and a DC loop, and do not interfere with each other.
Ac circuit：AC signal inputs two-conductor line circuit 104 from transformer 103 is exported, and is then flowed by node 209Branch's parallel circuit 105.It one in two, allows the primary of audio (exchange) signal stream overmatching transformer 106, makes its timeGrade being capable of drive the speaker 107.Then alternating current passes through 212 input fault wireless alarm units 204 of endpoint.Due to failure withoutThe design structure (referring to Fig. 5) of line alarm unit 204, for exchange, its impedance is much larger than branch's isolation capacitance 203.InstituteEndpoint 208 must flow through with exchange, then by branch's isolation capacitance 203, two-conductor line circuit 104 is returned using node 210.It then continues through isolation capacitance 202 and returns to output transformer 103, complete ac circuit.
DC loop：The anode of DC power supply 201 enters two-conductor line circuit 104 by endpoint 205.Direct current passes through theoretically103 grades of output transformer of zero impedance flow into parallel circuit 105 through endpoint 209；One in two, allow DC current streamThe primary of overmatching transformer 106.Theoretically, it is zero impedance to direct current.Then direct current enters failure by endpoint 212Wireless alarm units 204.
Due to the design structure (referring to Fig. 5) of wireless fault alarm unit 204, direct current will pass through power module 501(DC/DC conversion circuits) provides the energy for wireless fault alarm unit 204.Since isolation capacitance 203 is in theory to direct currentIt is insulator, impedance is far above wireless fault alarm unit 204, so direct current flows directly into endpoint 207, using endpoint210 flow into two-conductor line circuit 104.After the negative terminal 206 for reaching isolation capacitance 202, since isolation capacitance 202 is disconnected to direct currentRoad can only flow to 201 cathode of DC power supply, complete DC loop.
Each wireless fault alarm unit 204 monitors corresponding parallel circuit 105, matching transformer 106, loud speaker107 health status.If it find that they have any failure, will mode by radio communication in real time, it is wireless to fault messageCollector 302 is reported.Fault message wireless collector 302 is then reported to system controller 301 (referring to Fig. 6).This process is sent outIt is raw in time range (being less than 100 seconds at present), to complete the standard requirement of fault alarm as defined in fire protection criteria.
, it is apparent that limitation of these three circuits due to breaking component, can't interfere with each other.
Alternatively improved technology scheme, Fig. 4 are to be improved and obtained based on Fig. 2 structures.Difference lies in D with Fig. 3 for itPower-like amplifier 102 does not need to output transformer 103.So when being incorporated to DC power supply 201, it is necessary in power amplifierBetween the endpoint in 102 input two-conductor line circuits 104, an isolation inductance 211 is added in.This isolation inductance 211, on the one hand asPass through the direct current channel of theoretically zero impedance so that direct current is unlikely to puncture D-type power amplifier 102.On the other hand effectively everyFrom the node that D-type power amplifier 102 inputs two-conductor line circuit 104.
Further, wireless fault alarm unit 204 interior design as shown in figure 5, wireless fault alarm unit 204 by straightGalvanic electricity source module 501, micro-control unit (MCU) 502, load monitoring module 503, wireless communication module 504 is formed.
Because the impedance in two-conductor line circuit 104 is linear distribution, the input direct-current voltage of each parallel circuit 105And it differs.In order to ensure that wireless fault alarm unit 204 can work normally, so must have DC power supplier 501,Ensure the operating voltage of wireless fault alarm unit 204, stablize the numerical value in a design.Most common voltage be 3.3VDC or5.0VDC。
Micro-control unit (MCU) 502 is by its hardware capability and software programming, and control load monitoring module 503 is to parallel connectionCircuit 105, matching transformer 106, loud speaker 107 are continued to monitor.Micro-control unit (MCU) 502 also controls wireless telecommunicationsModule 504 provides communications protocol service by software programming, ensures the communication (ginseng between fault message wireless collector 302Examine Fig. 6).
Load monitoring module 503 judges whether loud speaker 107 connects circuit with it by monitoring the load of loud speaker 107Normal work.This module can select a kind of electromagnetism sensing module or other of such as Hall (Hall effect) monitoring elementCurrent measurement device.
Wireless communication module 504 can be with selection criteria module such as：IEEE802.11 series, Zigbee, bluetooth module etc..It can select using ISM band such as：433MHz, 902MHz etc., and the customized communications protocol of adapted ensure wireless fault alarmThe reliability and stability of unit 204.Wireless communication module 504 is connect with antenna 507, provides wireless transmitting function.
Fig. 6 is three circuit public broadcasting of two-conductor line and fault alarm hybrid system schematic diagram.Simplify the exchange represented in figureCircuit and DC loop are for example aforementioned.
Third circuit in technical solution of the present invention, as communication control circuit, the connection control of two-conductor line circuit 104 are logicalCircuit is interrogated, communication control circuit is the system controller 301 by being connected with each other, fault message wireless collector 302, antenna 303Composition, antenna 303 are connect by wireless communication channel 304 with 507 signal of antenna of wireless fault alarm unit 204, system controlDevice 301 processed is connect with source of sound 101.There must be between system controller 301 and wireless fault alarm unit 204 a kind of effectiveCommunication protocol, in accordance with the OSI structures of ISO, ensure that wireless communication channel 304 is unimpeded, to ensure the efficiency in communication control circuitAnd reliability.
Fig. 7 to Fig. 9 is another embodiment of the present invention：It is public using wired two-conductor line fire-fighting as fault alarmBroadcast system.Direct current needed for audio broadcasting function, component fault wired warning function and completion warning function is provided simultaneouslyPower supply.
Because audio broadcasting function and the DC power supply completed needed for warning function are identical with aforementioned function, hereinIt is not repeated.Therefore, Fig. 7 follows the common part in Fig. 6, only to fault wired alarm unit 224 and the wired receipts of fault messageStorage 310 proposes statement.
The design and wireless fault alarm unit 204 (with reference to figure 5) of fault wired alarm unit 224 (with reference to figure 8) are extremelyLikeness in form.Its difference is：Cancel antenna 507, wire communication module 514 replaces wireless communication module 504, wire communication module 514Externally it is connect with contact 207,209.
It is wire communication module 514 shown in Fig. 9.The control information of two-conductor line 104 is entered wired by contact 207 and 209The matching transformer 604 of communication module 514.After the amplification of low noise amplifier 603, entered by high-pass filter 602 and modulatedDemodulator 601.Signal after demodulation is output to micro-control unit (MCU) 502.
The signal (including failure alarm signal) that micro-control unit (MCU) 502 generates then first passes through modem 601 and adjustsCarrier frequency range is made, low frequency noise is eliminated using high-pass filter 602, becomes after being amplified by low noise amplifier 603 through overmatchingDepressor 604 is incorporated to two-conductor line 104.
The interior design of the wired collector 304 of fault message is substantially identical with fault wired alarm unit 224.It with it is doubleOne end that conducting wire 104 understands is identical with fault wired alarm unit 224.The other end then passes through micro-control unit (MCU)502, it is connected with software and hardware with system controller 301.
The system can only apply two-conductor line circuit, it will be able to be emergent/fire broadcast system, while provide audio broadcastingDC power supply needed for function, component fault alarm function and completion warning function.
Under this arrangement, audible communication circuit, direct current power supply loop and wireless telecommunications circuit can effectively and deposit.AndWith two-conductor line circuit form, while meet the double standards of fire-fighting and public broadcasting.
The present invention confirms its feasibility and practicability by specifically installing, testing.
The specific location of this system installation is the first and second floors of enterprise's office block, as Figure 10 and Figure 11 are shownShow.
Figure 10 is second floor wiring diagram.Wherein vertical channel 401 is the wire channel for penetrating through Stall and second floor floor.System coreThe heart 402 is mounted on the function showroom of second floor.The system core 402 includes system controller 301 as shown in Figure 6, source of sound101st, power amplifier 102, DC power supply 201, isolation inductance 211, isolation capacitance 202 etc..
Second floor is shown with fault information collection device 403 (i.e. fault message wireless collector 302 in figure six) mounted on functionOutside the wall of room.Its radio-frequency communication range can cover all loud speakers 405 of second floor.Fault information collection device 403 and the system coreBetween system controller 301 in 402, with standard ethernet road cable connection, in accordance with TCP/IP standard communication protocols.
Power amplifier 102, DC power supply 201 in the system core 402 are respectively by isolation inductance 211, isolation capacitance202, it is connected with common two-conductor line 404 and each loud speaker 405.15 loud speakers 405 are shared in second floor one, are numbered from 1 to 15.They are connected to two-conductor line 404 with mode in parallel.
Figure 11 is second floor wiring diagram.Stall is mounted on the smallpox outside TC workspaces with fault information collection device 403.Its radio frequencyCommunication context can cover all loud speakers 405 of Stall.In Stall fault information collection device 403 and the system core 402 isIt unites between controller 301, is connected with standard ethernet road cable by vertical channel 401, in accordance with TCP/IP standard communication protocols.
The two-conductor line 404 that the system core 402 connects reaches Stall by vertical channel 401.Then distinguished with parallel wayIt is connected with the loud speaker 405 of Stall.The loud speaker 405 1 of Stall shares 15, numbers from 16 to 30.
The two-conductor line fire-fighting public address system of this embodiment, official testing data are as follows：
Obviously, various changes and modifications can be made to the invention without departing from essence of the invention by those skilled in the artGod and range.In this way, if these modifications and changes of the present invention belongs to the range of the claims in the present invention and its equivalent technologyWithin, then the present invention is also intended to include these modifications and variations.