Protection system and protection method for fire-fighting two-bus

Abstract

The invention relates to a protection system and a protection method for a fire-fighting two-bus. The system comprises a protection detection circuit, a bus main control circuit and a single-chip microcomputer part, the protection detection circuit is electrically connected with the bus output negative end of the bus interface J1, the bus main control circuit and the single-chip microcomputer part, and when it is detected that a bus is abnormal, a fault protection driving signal is output to close the bus main control circuit, and meanwhile a fault feedback signal is output to the single-chip microcomputer part; the bus main control circuit is electrically connected with a bus output positive end of the bus interface J1 and is used for bus power switch control and communication information conversion output; the single-chip microcomputer part stops outputting the bus control signal to the bus main control circuit when receiving the fault feedback signal, and judges and analyzes the fault type according to the fault feedback signal. Compared with the prior art, the method has the advantages that the bus system is detected and protected in real time, and the reliability and safety of the bus system are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fire fighting two-bus, and in particular to a protection system and a protection method for a fire fighting two-bus. Background Art

[0002] As an important communication method in modern fire fighting systems, the fire fighting two-bus technology combines the dual functions of power supply and signal transmission, significantly reducing the wiring cost and construction complexity. However, there are still design defects and maintenance difficulties in this control method in practical applications. The bus control loop has a long line and a large number of access points. Once a node fails, it may cause the entire loop to paralyze, such as node short-circuit phenomena, loop-to-loop series connection phenomena that occur during construction, and strong electrical coupling phenomena on the bus caused by non-standard on-site construction. Node short-circuit phenomena often occur in the following situations: the interfaces of node products are short-circuited during construction; a certain point of the line is punctured and short-circuited during construction; short-circuit phenomena caused by abnormal problems of node products.

[0003] After retrieval, Chinese Patent Application Publication No. CN112650089A discloses a design circuit and a detection method integrating two-bus short-circuit detection and isolation, including an ARM processor chip, an input and output interface circuit, a rectifier bridge chip, a power conversion chip, a two-bus communication conversion chip, a communication indicator light, a two-bus transceiver control chip, a two-bus transceiver control chip, a two-bus self-checking circuit, a program download and debugging circuit, a relay, a buzzer, and a DIP switch; it can effectively perform regular self-checks on the two-bus, detect faults in advance; and perform a self-check operation before controlling the two-bus to avoid potential safety hazards; when detecting abnormalities, it will alarm in time to notify the customer to repair in time. This existing patent application has the problems of not detecting bus abnormalities in real time and not analyzing and judging faults.

[0004] Therefore, a simple and intelligent protection and detection means is needed to realize the automatic adjustment, control and problem troubleshooting of the bus, so as to provide a more efficient and safe bus control solution.

[0005] How to achieve real-time protection and fault detection of the fire fighting two-bus has become a technical problem to be solved. Summary of the Invention

[0006] The purpose of the present invention is to overcome the above-mentioned defects existing in the prior art and provide a protection system and a protection method for a fire fighting two-bus.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] According to one aspect of the present invention, a protection system for a fire fighting two-bus is provided, and the system includes a protection detection circuit, a bus main control circuit, and a single-chip microcomputer part;

[0009] The protection detection circuit is electrically connected to the "negative bus output" terminal of the bus interface J1, the bus main control circuit, and the single-chip microcomputer part respectively. When a bus anomaly is detected, it outputs a fault protection drive signal to the bus main control circuit to turn off the bus main control circuit, and at the same time outputs a fault feedback signal to the single-chip microcomputer part;

[0010] The bus main control circuit is electrically connected to the "positive bus output" terminal of the bus interface J1 and is used for bus power switch control and communication information conversion output;

[0011] When the bus is operating normally, the single-chip microcomputer part outputs a bus control signal to the bus main control circuit. When it receives the fault feedback signal, it stops outputting the bus control signal to the bus main control circuit and judges and analyzes the fault type according to the fault feedback signal.

[0012] Preferably, the protection detection circuit includes an abnormal signal acquisition circuit, a hardware protection circuit, and a protection failure circuit that are electrically connected in sequence, and also includes a signal feedback circuit that is electrically connected to the abnormal signal acquisition circuit and the hardware protection circuit;

[0013] The abnormal signal acquisition circuit is used to detect the bus condition in real time. When a bus fault is detected, the hardware protection circuit and the signal feedback circuit convert the bus abnormal signal into a fault protection drive signal and a fault feedback signal respectively;

[0014] The protection failure circuit is used to temporarily ensure the failure of the hardware protection circuit during the bus restoration operation of the single-chip microcomputer.

[0015] More preferably, the abnormal signal acquisition circuit includes a resistor R5 and a one-way filtering circuit formed by a diode D1, a resistor R6, and a capacitor C1. One end of the resistor R5 and the diode D1 is electrically connected to the "negative bus output" terminal of the bus interface J1, and the other end of the resistor R5 is grounded;

[0016] The hardware protection circuit includes a current-limiting resistor R7 and a driving transistor Q2. The base of the driving transistor Q2 is connected to the abnormal signal acquisition circuit through the current-limiting resistor R7. The emitter of the driving transistor Q2 is grounded, and the collector outputs a fault protection drive signal to the bus main control circuit;

[0017] The protection failure circuit includes a triode Q4 and a parallel-connected resistor R10 and resistor R11. The base of the triode Q4 is connected to one end of the resistor R10 and the resistor R11 respectively. The emitter of the triode Q4 is grounded together with the other end of the resistor R10 and the resistor R11 and is electrically connected to the single-chip microcomputer part. The collector of the triode Q4 is electrically connected to the base of the driving transistor Q2 in the hardware protection circuit;

[0018] The signal feedback circuit includes transistor Q3, resistor R9, and resistor R8. The base of transistor Q3 is electrically connected to the abnormal signal acquisition circuit and the hardware protection circuit through resistor R9, the emitter is grounded, and the collector is connected to VCC through resistor R8 and outputs a fault feedback signal FBACK_Sig to the single-chip microcomputer part.

[0019] More preferably, the protection detection circuit collects the bus voltage signal through resistor R5 in real time. When the bus works normally, a current is formed with a load on bus interface J1 and is converted into a weak voltage signal through resistor R5. At this time, the protection detection circuit does not work.

[0020] Preferably, the bus main control circuit includes a controlled terminal circuit and a control terminal circuit;

[0021] The controlled terminal circuit includes resistor R2, resistor R3, resistor R4, and driving transistor Q1. One end of the controlled terminal circuit is connected to the single-chip microcomputer control signal, the other end is connected to the bus power supply, and is electrically connected to the "positive bus output" terminal of bus interface J1 through the control terminal circuit and fuse F1;

[0022] There is a driving transistor Q1 electrically connected between the control terminal circuit and the single-chip microcomputer part. The emitter of driving transistor Q1 is grounded through resistor R4. The base of driving transistor Q1 is respectively connected to one ends of resistor R2 and resistor R3. The other end of resistor R3 is grounded. The other end of resistor R2 is connected to the single-chip microcomputer. The emitter of driving transistor Q1 is connected to the bus power supply through resistor R1. The emitter of driving transistor Q1 is also connected to the other end of the control terminal circuit.

[0023] Preferably, the single-chip microcomputer part includes BUS_Con1 pin, FBACK_Sig pin, and RESET_Con pin;

[0024] The BUS_Con1 pin outputs a bus control signal BUS_Con1 when the bus works normally and is electrically connected to the bus main control circuit;

[0025] The FBACK_Sig pin receives a fault feedback signal from the protection detection circuit for the single-chip microcomputer to judge the fault type;

[0026] The RESET_Con pin is used to output a bus restoration drive signal to the protection detection circuit when it is judged that the bus fault is a short circuit, so that the fault protection drive signal PRO_Con for driving the bus main control circuit by the protection detection circuit is temporarily invalid.

[0027] More preferably, when the fault feedback signal is restored, the single-chip microcomputer part clears the abnormal communication data and resumes providing the bus control signal to the bus main control circuit.

[0028] According to another aspect of the present invention, there is provided a protection method for a two-wire fire alarm system, the method comprising:

[0029] When the protection detection circuit detects an abnormality in the bus, it converts the abnormality signal into a fault protection drive signal PRO_Con and a fault feedback signal FBACK_Sig, and automatically drives the main control circuit of the bus to close through the fault protection drive signal, so that the bus loses power to protect the bus system;

[0030] If the fault feedback signal shows a falling edge change, it indicates that a fault has occurred in the bus loop;

[0031] Analyze the fault feedback signal to determine the type of bus fault.

[0032] Preferably, the process of analyzing the fault feedback signal to determine the type of bus fault includes:

[0033] Step 101, if the fault feedback signal shows a rising edge, a short circuit fault has occurred in the current bus loop; otherwise, there are two other cases, including a series-connected loop fault and a strong electrical coupling fault of the bus, and step 102 is executed;

[0034] Step 102, turn off other bus loops in sequence. If a rising edge appears in the feedback signal, there is a loop series connection, and the series-connected loop is inferred, and the bus series connection fault information and the corresponding series number are sent, and step 103 is executed;

[0035] Step 103, if all bus loops are turned off and no rising edge appears in the feedback signal, it is a strong electrical coupling fault, and the bus strong electrical coupling fault information is sent.

[0036] Preferably, for a short circuit fault, a bus restoration operation is performed. If it is determined to be a short circuit fault after three bus restoration operations, the bus short circuit fault information is sent; if it returns to normal after one or two restoration operations, it is determined to be an accidental short circuit, and the bus risk warning information is sent.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1) The present invention detects the situation of the bus in real time. When an abnormality in the bus is detected, it can automatically and quickly turn off the bus output to achieve automatic protection of the bus system; at the same time, the type of fault is judged according to the fault feedback signal, and an effective problem closed-loop helps to quickly restore the bus system to normal, further improving the reliability and safety of the bus system.

[0039] 2) For a short circuit fault, the present invention strategically performs a bus restoration operation to verify whether it is a real short circuit or an accidental short circuit, preventing accidental faults from affecting communication and eliminating communication information confusion during faults.

[0040] 3) The present invention can identify various faults such as short circuits, series connections, and strong electrical coupling. Quickly closing the bus output can effectively prevent the fuse in the bus loop from failing, protect the bus main control circuit and components from damage caused by faults, and make the bus system more stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic structural diagram of the protection system in the present invention;

[0042] Figure 2 It is a schematic flow diagram of the protection method in the present invention;

[0043] Figure 3 It is a schematic waveform diagram of the fault feedback signal 1 in the present invention;

[0044] Figure 4 It is a schematic waveform diagram of the fault feedback signal 2 in the present invention;

[0045] Figure 5 It is a schematic waveform diagram of the fault feedback signal 3 in the present invention;

[0046] Figure 6 It is a schematic waveform diagram of the fault feedback signal 4 in the present invention;

[0047] In the drawings, F1 is a fuse, J1 is a bus interface, BUS_Con1 is a bus control signal, PRO_Con is a fault protection drive signal, FBACK_Sig is a fault feedback signal, and RESET_Con is a bus restoration drive signal. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0049] The present invention provides a protection system and a protection method for solving various on-site problems of the fire protection two-wire bus, aiming to protect, detect, and process various on-site problems existing in the existing fire protection two-wire control system, where the on-site problems include short circuit phenomena, series connection phenomena between loops, and strong electrical coupling phenomena.

[0050] This embodiment relates to a protection system for a fire protection two-wire bus, as Figure 1 , including:

[0051] (1) Protection and Detection Circuit: This part is used to protect and detect the short - circuit phenomenon, series connection between loops, and external strong - electricity coupling phenomenon of the fire - fighting two - wire bus (hereinafter referred to as the bus). The protection and detection circuit is respectively connected to the "negative bus output" terminal of the bus interface J1, the bus main control circuit, and the single - chip microcomputer part, and converts the bus abnormal signal into a fault protection drive signal and a fault feedback signal.

[0052] The protection and detection circuit includes an abnormal signal acquisition circuit, a hardware protection circuit, and a protection failure circuit that are electrically connected in sequence. The abnormal signal acquisition circuit and the hardware protection circuit are also electrically connected to the signal feedback circuit.

[0053] The abnormal signal acquisition circuit includes a resistor R5 and a one - way filtering circuit formed by a diode D1, a resistor R6, and a capacitor C1. One end of the resistor R5 and the diode D1 is electrically connected to the "negative bus output" terminal of the bus interface J1, and the other end of the resistor R5 is grounded.

[0054] The hardware protection circuit includes a current - limiting resistor R7 and a driving transistor Q2. The base of the driving transistor Q2 is connected to the abnormal signal acquisition circuit through the current - limiting resistor R7. The emitter of the driving transistor Q2 is grounded, and the collector outputs a fault protection drive signal PRO_Con to the base of the triode Q1 in the controlled - end circuit of the bus main control circuit.

[0055] The protection failure circuit includes a triode Q4 and resistors R10 and R11 connected in parallel. The base of the triode Q4 is respectively connected to one end of the resistors R10 and R11. The emitter of the triode Q4 is grounded together with the other ends of the resistors R10 and R11 and is electrically connected to the RESET_Con pin of the single - chip microcomputer part. The collector of the triode Q4 is electrically connected to the base of the driving transistor Q2 in the hardware protection circuit.

[0056] The signal feedback circuit includes a transistor Q3, a resistor R9, and a resistor R8. The base of the transistor Q3 is electrically connected to the abnormal signal acquisition circuit and the hardware protection circuit through the resistor R9, the emitter is grounded, and the collector is connected to VCC through the resistor R8 and outputs a fault feedback signal FBACK_Sig to the FBACK_Sig pin of the single - chip microcomputer part.

[0057] (2) Bus Main Control Circuit: This part is used for the bus power - supply switch and communication - information conversion and output functions, and is controlled by the single - chip microcomputer part and the hardware protection circuit of the protection and detection circuit. The bus main control part includes a control - end circuit and a controlled - end circuit. The control - end circuit is connected to the fire - fighting two - wire bus, and the controlled - end is connected to the protection and detection circuit and the single - chip microcomputer part.

[0058] The controlled terminal circuit includes resistor R2, resistor R3, resistor R4, and driving transistor Q1. One end of the controlled terminal circuit is connected to the BUS_Con1 pin of the single-chip microcomputer control signal, the other end is connected to the bus power supply, and is connected to the "positive bus output" end of the bus interface J1 through the controlled terminal circuit and fuse F1. There is a driving transistor Q1 electrically connected between the controlled terminal circuit and the single-chip microcomputer control signal BUS_Con1. The emitter of the driving transistor Q1 is grounded through resistor R4. The base of the driving transistor Q1 is connected to one end of each of resistor R2 and resistor R3. The other end of resistor R3 is grounded, and the other end of resistor R2 is connected to the single-chip microcomputer control signal BUS_Con1. The emitter of the driving transistor Q1 is connected to the bus power supply through resistor R1, and the emitter of the driving transistor Q1 is also connected to the other end of the controlled terminal circuit.

[0059] (3) Single-chip microcomputer part: Receive the fault feedback signal from the protection detection circuit, judge and analyze it, output the bus control signal to the bus main control circuit, and perform restoration operation control and communication and other algorithm processing core processing components when detecting a bus short circuit.

[0060] Such as Figure 1 , BUS_Con1, the bus control signal, provides a normal driving signal by the single-chip microcomputer to control the transmission of bus information and energy.

[0061] PRO_Con, the fault protection driving signal, is given by driving triode Q2. When a fault occurs, the protection detection circuit drives triode Q2 to pull down the control of transistor Q1.

[0062] FBACK_Sig, the fault feedback signal, is used for the single-chip microcomputer to detect and judge.

[0063] RESET_Con, the bus restoration driving signal, is a driving signal that makes the protection detection circuit temporarily ineffective when the single-chip microcomputer attempts to restore the bus. The single-chip microcomputer controls resistor R10, resistor R11, and triode Q4 to make driving triode Q2 unable to pull down the BUS_Con1 bus main control signal.

[0064] This embodiment also relates to a protection method for a two-wire fire bus. When a fault or abnormality occurs on the bus, an abnormal signal occurs on the two-wire fire bus, resulting in an abnormal voltage signal at the "negative bus output" end of the bus interface J1.

[0065] Including:

[0066] 1) In case of a short circuit fault, the "positive bus output" end of the same loop is connected to the "negative bus output" end;

[0067] 2) In case of a series connection fault, the "positive bus output" end of other loops is connected to the "negative bus output" end of this loop;

[0068] 3) When a strong current coupling fault occurs, when laying cables on site, the coupling voltage caused by laying strong and weak current in the same pipe is applied to the bus. The "bus output negative" end is coupled to an out-of-range voltage.

[0069] Specifically, when a short circuit occurs, the voltage at the "bus output positive" end is directly connected to the "bus output negative" end, that is, the voltage at the "bus output positive" end is added to the resistor R5 of the protection detection circuit. At this time, the voltage across resistor R5 is the bus voltage, which passes through the unidirectional filtering circuit formed by diode D1, resistor R6 and capacitor C1, and then enters the current limiting resistor R7 of the hardware protection circuit to drive transistor Q2, thereby lowering the driving level of transistor Q1 of the controlled end circuit of the bus main control circuit, causing the bus driving circuit of the control end circuit to fail, followed by the failure of the control end circuit, and the bus power supply has no voltage, thereby playing a role in protecting the circuit.

[0070] like Figure 2 The protection method of the present invention comprises the following steps:

[0071] (1) The protection detection circuit automatically detects the bus status. When the signal voltage of the abnormal signal acquisition circuit reaches the threshold, it determines that the bus has a fault and automatically drives to shut down the bus main control circuit. At the same time, it provides the microcontroller part with a bus abnormality fault feedback signal FBACK_Sig.

[0072] (2) When the bus master control circuit receives the fault protection driving signal PRO_Con from the protection detection circuit, the bus control signal BUS_Con1 provided by the single-chip microcomputer is terminated, and the controlled end circuit of the bus master control circuit is turned off, and no power and signal are provided to the bus.

[0073] (3) After receiving the fault feedback signal FBACK_Sig from the protection detection circuit, the MCU will stop providing the bus control signal BUS_Con1 to the bus master control circuit and transmit the bus fault status to the host through communication. When the fault feedback signal FBACK_Sig is restored, the MCU clears the abnormal communication data and resumes providing the bus control signal BUS_Con1 to the bus master control circuit.

[0074] Through the above steps, the present invention realizes the automatic protection and adjustment of the bus in an abnormal state through the protection detection circuit. The protection detection circuit can identify short - circuit phenomena, series - connection phenomena, and strong - electricity coupling phenomena occurring in the field bus (through a circuit, three problems that often occur in the fire - fighting two - wire field can be solved, protecting the bus control main board and other components such as loop fusing fuses). After receiving the feedback signal, the single - chip microcomputer part stops controlling the main control part of the bus and reminds professionals to carry out maintenance. Through the control strategy, the automatic protection control of the bus and the analysis and feedback of bus faults are realized. This solution makes the debugging of the bus system more convenient, further improving the reliability and safety of the bus system; non - standard problems occurring during construction can be timely reminded and feedbacked, facilitating the troubleshooting of on - site problems.

[0075] When the bus is operating normally, the BUS_Con1 pin of the single - chip microcomputer part controls the PWM (pulse - width modulation) signal to the controlled - end circuit (resistors R2, R3, and driving transistor Q1) of the bus main control circuit, and then through resistors R1 and R4, the 0V - VCC level signal is converted into a level signal that the controlled - end circuit can accept; then, through fuse F1, bus interface J1 (with load), and resistor R5 of the protection detection circuit, a loop is formed. The protection detection circuit continuously collects the bus voltage signal through resistor R5. When the bus is working normally, the fire - fighting two - wire bus has a load to form a current, which is converted into a weak voltage signal through resistor R5. At this time, the protection detection circuit does not work.

[0076] When the protection detection circuit detects any one of the three faults (bus short - circuit phenomenon, series - connection phenomenon between loops, and external strong - electricity coupling phenomenon) occurring in the bus, the driving triode Q2 pulls down the fault - protection driving signal PRO_Con of the bus main control circuit, making it lose its driving ability, so that the bus main control circuit fails and the fire - fighting two - wire bus is turned off; on the other hand, the fault - feedback signal FBACK_Sig is fed back to the single - chip microcomputer part, and the single - chip microcomputer part analyzes through the fault - feedback signal FBACK_Sig to judge the problems occurring in the bus.

[0077] When a short - circuit fault, series - connection fault between loops, or strong - electricity coupling fault occurs in the bus system, the protection detection circuit immediately converts the abnormal signal into a fault - protection driving signal PRO_Con and a fault - feedback signal FBACK_Sig at the first time of operation. The fault - protection driving signal more directly shuts down the bus main control circuit, making the bus lose power, thus protecting the bus control line (the line of the bus main control circuit) and components from damage caused by the fault.

[0078] If the fault - feedback signal is a downward - pulse feedback signal, that is, there is a falling edge, it indicates that there is a fault in the bus loop. The single - chip microcomputer part judges the bus fault situation through the fault - feedback signal FBACK_Sig, specifically including:

[0079] If a rising edge appears in the fault feedback signal, it indicates that a short - circuit fault has occurred in the current bus loop; otherwise, if no rising edge appears, it is for the other two cases (series - connected loop and strong - electricity coupling fault in the bus):

[0080] Turn off other bus loops in sequence. If a rising edge appears in the feedback signal, there is a loop series - connection, and the series - connected loop can be inferred (the last bus loop turned off is the series - connected loop), send the bus series - connection fault information and the corresponding series - connection serial number; the corresponding fault feedback signal is as Figure 4 。

[0081] If all bus loops are turned off and no rising edge appears in the feedback signal, it is strong - electricity coupling, and send the bus strong - electricity coupling fault information; the corresponding fault feedback signal is as Figure 6 。

[0082] For a short - circuit fault, perform the bus restoration operation. If it is judged as a short - circuit fault after three bus restoration operations, the corresponding fault feedback signal is as Figure 3 , then send the bus short - circuit fault information; if it returns to normal after one or two bus restoration operations, send the bus risk warning information, and the corresponding fault feedback signal is as Figure 5 。

[0083] After the single - chip microcomputer part detects the change in the fault feedback signal of the protection detection circuit, it turns off the PWM output of the BUS_Con1 pin of the bus control signal.

[0084] After a continuous short - circuit occurs, the single - chip microcomputer software algorithm will generate three bus restoration operations with an interval of 3S. There will be a waveform as Figure 3 ( Figure 2 the feedback signal 1 in it). During the restoration operation, the single - chip microcomputer part controls the RESET_Con pin, and the hardware protection circuit formed by resistor R10, resistor R11, and transistor Q4 ensures that the hardware protection fails. Then, restore the PWM output control of the BUS_Con1 pin. If a single or two bus restoration successes occur, such as Figure 5 ( Figure 2 the feedback signal 3 in it), it indicates that the bus is accidentally short - circuited. For example, accidental short - circuits may occur during installation, such as accidental connection. Remind of the short - circuit risk in the bus system loop and send the bus risk warning information.

[0085] When a loop is connected in series, for example, the "bus output negative" end of the current bus loop and the "bus output positive" end of another loop are short-circuited (in actual applications, the control host has multiple two-bus control loops and uses the same switching power supply), that is, the voltage of the "bus output positive" end of the other loop is added to the resistor R5 of the protection detection circuit. At this time, the voltage across the resistor R5 is the bus voltage, which passes through the unidirectional filtering circuit formed by the diode D1, the resistor R6, and the capacitor C1, and then enters the current limiting resistor R7 and the driving transistor Q2 of the hardware protection circuit to work, pulling down the driving level of the transistor Q1 of the controlled end circuit of the bus main control circuit, making the driving circuit invalid, and then the "bus control end" fails, the bus has no power supply voltage, and plays a role in protecting the circuit.

[0086] At the same time, the fault feedback signal generated by the protection detection circuit is given to the microcontroller. After passing through the unidirectional filtering circuit formed by the diode D1, the resistor R6 and the capacitor C1, the other way passes through the signal feedback circuit formed by the resistor R9, the resistor R8 and the transistor Q3, pulling the FBACK_Sig signal from a high level to a low level.

[0087] After the microcontroller detects the change of the fault feedback signal generated by the protection detection circuit, it turns off the PWM output of the BUS_Con1 pin. At this time, the "bus output positive" end of the current loop is turned off, and the fault feedback information is not restored. Figure 6 Then, the other loop buses are closed in turn through the microcontroller software algorithm to check whether the fault feedback signal has a rising change. If a rising edge appears, such as Figure 4 As shown, it means that there is a serial connection with other loop buses, so find the loop connected in series with it. If all channels are closed without affecting the rise of the fault feedback signal, it means that there is a strong electrical coupling in the bus loop.

[0088] When a strong electric coupling fault occurs, both the "bus output positive" pin and the "bus output negative" pin are subject to a strong electric coupling voltage, and the "bus output negative" pin is more prominent at this time. The strong electric coupling voltage is applied to the "bus output negative" pin, that is, the strong electric coupling voltage is applied to the resistor R5 of the protection detection circuit. At this time, the voltage across the resistor R5 is a coupling voltage, which passes through the unidirectional filtering circuit formed by the diode D1, the resistor R6, and the capacitor C1, and then enters the current limiting resistor R7 and the driving transistor Q2 of the hardware protection circuit to work, pulling down the driving level of the transistor Q1 of the controlled end circuit of the bus main control circuit, making the driving circuit invalid, and then the "bus control end" fails, and the bus has no power supply voltage, which plays a role in protecting the circuit.

[0089] Meanwhile, a fault feedback signal generated by the protection detection circuit is sent to the microcontroller. After passing through the unidirectional filtering circuit formed by diode D1, resistor R6, and capacitor C1, another path passes through the signal feedback circuit formed by resistor R9, resistor R8, and transistor Q3, pulling the FBACK_Sig signal from high level to low level.

[0090] After the microcontroller part detects the change in the fault feedback signal of the protection detection circuit, it turns off the PWM output of the BUS_Con1 pin. The change in the fault feedback signal that appears here is as Figure 6 shown (feedback signal 2). At this time, the "positive bus output" of the current loop is turned off, and the fault feedback information is not restored).

[0091] The electronic device of the present invention includes a central processing unit (CPU), which can execute various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) or computer program instructions loaded from a storage unit into a random access memory (RAM). In the RAM, various programs and data required for device operation can also be stored. The CPU, ROM, and RAM are connected to each other through a bus. An input / output (I / O) interface is also connected to the bus.

[0092] Multiple components in the device are connected to the I / O interface, including: an input unit, such as a keyboard, mouse, etc.; an output unit, such as various types of displays, speakers, etc.; a storage unit, such as a disk, optical disc, etc.; and a communication unit, such as a network card, modem, wireless communication transceiver, etc. The communication unit allows the device to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0093] The processing unit executes the various methods and processes described above. For example, in some embodiments, the method can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program can be loaded and / or installed onto the device via the ROM and / or the communication unit. When the computer program is loaded into the RAM and executed by the CPU, one or more steps of the method described above can be executed. Alternatively, in other embodiments, the CPU can be configured to execute the method in any other suitable way (e.g., by means of firmware).

[0094] The functions described above herein can be at least partially performed by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that can be used include: field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on a chip (SOCs), complex programmable logic devices (CPLDs), and so on.

[0095] The program code for implementing the method of the present invention can be written in any combination of one or more programming languages. These program codes can be provided to the processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing devices, such that when the program codes are executed by the processor or controller, the functions / operations specified in the flowchart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, executed partially on the machine as an independent software package and partially on a remote machine, or executed entirely on a remote machine or server.

[0096] In the context of the present invention, a machine-readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0097] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A fire protection two-bus system, characterized in that: The system includes a protection detection circuit, a bus main control circuit and a single chip microcomputer part; The protection detection circuit is electrically connected to the "bus output negative" end of the bus interface J1, the bus master control circuit and the single-chip microcomputer part respectively. When a bus abnormality is detected, a fault protection drive signal is output to the bus master control circuit to shut down the bus master control circuit, and a fault feedback signal is output to the single-chip microcomputer part at the same time; The bus main control circuit is electrically connected to the "bus output positive" terminal of the bus interface J1, and is used for bus power switch control and communication information conversion output; The single chip microcomputer part outputs a bus control signal to the bus main control circuit when the bus is working normally, stops outputting the bus control signal to the bus main control circuit when receiving a fault feedback signal, and determines and analyzes the fault type according to the fault feedback signal.

2. A fire protection two-bus system according to claim 1, characterized in that: The protection detection circuit includes an abnormal signal acquisition circuit, a hardware protection circuit and a protection failure circuit which are electrically connected in sequence, and also includes a signal feedback circuit which is electrically connected to the abnormal signal acquisition circuit and the hardware protection circuit; The abnormal signal acquisition circuit is used to detect the bus condition in real time. When a bus fault is detected, the hardware protection circuit and the signal feedback circuit convert the bus abnormal signal into a fault protection drive signal and a fault feedback signal respectively; The protection failure circuit is used to temporarily ensure that the hardware protection circuit fails during the bus recovery operation of the single-chip microcomputer.

3. A fire protection two-bus system according to claim 2, characterized in that: The abnormal signal acquisition circuit includes a resistor R5 and a unidirectional filtering circuit formed by a diode D1, a resistor R6 and a capacitor C1, one end of the resistor R5 and the diode D1 is electrically connected to the "bus output negative" end of the bus interface J1, and the other end of the resistor R5 is grounded; The hardware protection circuit includes a current limiting resistor R7 and a driving transistor Q2, the base of the driving transistor Q2 is connected to the abnormal signal acquisition circuit via the current limiting resistor R7, the emitter of the driving transistor Q2 is grounded, and the collector outputs a fault protection driving signal to the bus main control circuit; The protection failure circuit includes a transistor Q4 and a resistor R10 and a resistor R11 connected in parallel. The base of the transistor Q4 is connected to one end of the resistor R10 and the resistor R11 respectively. The emitter of the transistor Q4 and the other end of the resistor R10 and the resistor R11 are grounded together and electrically connected to the single-chip computer part. The collector of the transistor Q4 is electrically connected to the base of the driving transistor Q2 in the hardware protection circuit. The signal feedback circuit includes a transistor Q3, a resistor R9 and a resistor R8. The base of the transistor Q3 is electrically connected to the abnormal signal acquisition circuit and the hardware protection circuit through the resistor R9, the emitter is grounded, the collector is connected to VCC through the resistor R8, and a fault feedback signal FBACK_Sig is output to the microcontroller part.

4. A fire protection two-bus system according to claim 3, characterized in that: The protection detection circuit collects the bus voltage signal through the resistor R5 in real time. When the bus works normally, the bus interface J1 carries a load to form a current which is converted into a weak voltage signal through the resistor R5. At this time, the protection detection circuit does not work.

5. A fire protection two-bus system according to claim 1, characterized in that: The bus master control circuit comprises a controlled end circuit and a control end circuit; The controlled end circuit includes resistors R2, R3, R4 and a driving transistor Q1. One end of the controlled end circuit is connected to the single-chip control signal, and the other end is connected to the bus power supply. The controlled end circuit is electrically connected to the "bus output positive" end of the bus interface J1 through the control end circuit and the fuse F1. A driving transistor Q1 is electrically connected between the control end circuit and the single-chip microcomputer part. The emitter of the driving transistor Q1 is grounded through a resistor R4. The base of the driving transistor Q1 is connected to one end of a resistor R2 and a resistor R3 respectively. The other end of the resistor R3 is grounded. The other end of the resistor R2 is connected to the single-chip microcomputer. The emitter of the driving transistor Q1 is connected to the bus power supply through the resistor R1. The emitter of the driving transistor Q1 is also connected to the other end of the control end circuit.

6. A fire protection two-bus system according to claim 1, characterized in that: The single chip microcomputer part includes a BUS_Con1 pin, a FBACK_Sig pin and a RESET_Con pin; The BUS_Con1 pin outputs a bus control signal BUS_Con1 when the bus is working normally, and is electrically connected to the bus main control circuit; The FBACK_Sig pin receives a fault feedback signal from the protection detection circuit, which is used by the microcontroller to determine the fault type; The RESET_Con pin is used to output a bus recovery drive signal to the protection detection circuit when the bus fault is determined to be a short circuit, so that the protection detection circuit drives the fault protection drive signal PRO_Con that shuts down the bus main control circuit to be temporarily invalid.

7. A fire protection two-bus system according to claim 6, characterized in that: When the fault feedback signal is restored, the single chip microcomputer part clears the abnormal communication data and resumes providing the bus control signal to the bus main control circuit.

8. A protection method for a fire protection two-bus protection system using any one of claims 1 to 7, characterized in that: The method includes: When the protection detection circuit detects an abnormality in the bus, it converts the abnormal signal into a fault protection drive signal PRO_Con and a fault feedback signal FBACK_Sig, and automatically drives the bus main control circuit to shut down through the fault protection drive signal, causing the bus to lose power and thus protecting the bus system; If the fault feedback signal changes to a falling edge, it indicates that the bus loop is faulty; The microcontroller part analyzes the fault feedback signal to determine the type of bus fault.

9. The method according to claim 8, characterized in that The process of analyzing the fault feedback signal to determine the type of bus fault includes: Step 101, if the fault feedback signal has a rising edge, a short circuit fault occurs in the current bus loop; otherwise, it is another two cases, wherein the other case includes a series circuit fault and a bus strong electric coupling fault, and step 102 is executed; Step 102, turn off other bus loops in turn. If the feedback signal has a rising edge, there is a loop connection, and the loop connected in series is inferred, and the bus connection fault information and the corresponding connection sequence number are sent, and step 103 is executed; Step 103: If all bus loops are turned off and there is still no rising edge in the feedback signal, it is a strong electric coupling fault, and bus strong electric coupling fault information is sent.

10. The method according to claim 8, characterized in that For short-circuit faults, bus restoration operations are performed. If a short-circuit fault is determined after three bus restoration operations, a bus short-circuit fault message is issued. If the fault returns to normal after one or two restoration operations, it is determined to be an accidental short circuit and a bus risk warning message is issued.

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