CN107437849B - On-line Switch Modulation Digital Communication Control System for Local Power Network - Google Patents

Abstract

The utility model discloses a local power utilization network on-line switch modulation digital communication control system, which comprises a master network controller and a slave network controller. The master and slave network controllers form a local area communication network through a power supply line. The main network controller sends information by controlling the power switch to generate instant power failure pulses with different pulse widths on the power supply line, and the auxiliary network controller detects and records the instant power failure pulses with different pulse widths through the information extraction circuit to acquire the information. The utility model realizes the data communication between the master network controller and the slave network controller according to different pulse widths representing different data information. The intelligent control system has the beneficial effects of simple control mode, long transmission distance, no energy consumption and low cost, and can realize intelligent control on LED illumination and other electric equipment.

Description

On-line Switch Modulation Digital Communication Control System for Local Power Network

technical field

The invention relates to a power supply network control system, in particular to a digital communication control system for on-line switch modulation of a local power consumption network.

Background technique

The management of the local power network is an important part of the management and control of the power network management. With the continuous development of smart home, industrial automation control, and remote information management of the Internet of Things, the market demand for the management of local power consumption networks is becoming more and more urgent. Under the current technical environment, GPRS or wired power carrier is used to control the monitoring and management of multiple electrical equipment on a power supply line for local area electrical equipment network management. This method has high manufacturing costs, a large number of equipment, and cumbersome use and maintenance. and relatively high cost.

Patent No. CN201520416793 discloses an off-line network management and control system for local electrical equipment. The utility model discloses an off-line network management and control system for local electric equipment. The system includes a power supply line. The power supply input start end of the power supply line is connected in series with a power supply control switch K1, and the switch K1 is connected in parallel with a An off-line network power management controller and a communication interface switch K2, the power supply line is also connected to a number of parallel-connected electrical appliances, and each of the electrical appliances is respectively connected to a slave network controller; the off-line network power management controller includes a master A network controller, the input end of the main network controller is connected with a power input interface, keyboard, Internet interface and USB interface, and the output end of the main network controller is connected with a power output interface, a data communication interface, a display and a warning light . The system can complete the function of manual and automatic control switch power transmission; in the off-line state, it can communicate with the single chip computer to realize the monitoring and management function; it can realize the communication function with the computer, mobile phone and the Internet through the USB interface and the Internet interface. The utility model has a single communication function and cannot meet the increasing control requirements of electric appliances.

Patent No. CN102118183A power carrier communication method and device, including the following steps: the information collection step, the physical layer receives the pilot signal to obtain channel state information; the synchronization state information step, the physical layer and the data transmission control layer synchronize the channel state information ; The information processing step, according to the channel state information, obtains the data packets that need and can be communicated; the communication step, taking turns to occupy the time period to transmit the data packets that need and can be communicated. The communication principle is complex, inconvenient to use, and poor in practicability.

Therefore, it is an urgent requirement to design a low-cost, simple control method, and easy for grass-roots technicians to master and use the local area power network communication control system.

Contents of the invention

The technical problem to be solved by the present invention is to provide a digital communication control system for on-line switch modulation of domain electricity network, which has the functions of simple structure, convenient operation, long transmission distance, high communication efficiency, low cost and strong practicability.

The technical solution of the technical problem to be solved by the present invention is: a digital communication control system for on-line switch modulation of a local power network, which is characterized in that it includes a master network controller and a slave network controller. The main network controller includes a power switch, a drive control circuit, a main microcontroller, a power-off buffer circuit, and an Internet of Things communication module electrically connected to the main microcontroller, a keyboard, a display unit, a grid synchronization signal extraction circuit, and a main power supply. module. The power switch is connected in series in the power supply line, a power-off buffer circuit is connected in series between the input end of the drive control circuit and the main microcontroller, the output end of the drive control circuit is electrically connected with the control end of the power switch, and the The main power supply module is electrically connected to the power supply line at the power grid end of the input end of the power switch, and the grid synchronous signal extraction circuit is electrically connected to the power supply line at the rear end of the power switch output end. The slave network controller includes a slave microcontroller, a synchronous information extraction circuit, a power supply module, and a slave control unit, and the slave microcontroller is electrically connected with the synchronization information extraction circuit, a slave power supply module, and a slave control unit. The synchronous information input circuit is electrically connected from the power supply module to the power supply line at the rear end of the power switch output end.

More preferably, the power supply line is an AC power grid.

More preferably, the grid synchronous signal extraction circuit includes a first current limiting resistor, a second current limiting resistor, a first rectifier bridge, a first optocoupler, an AC input terminal of the first rectifier bridge and a power switch output terminal A first current-limiting resistor and a second current-limiting resistor are respectively connected in series between the zero and live wires of the power supply line at the rear end, and the DC output terminal of the first rectifier bridge is electrically connected to the positive and negative poles of the input terminal of the first photocoupler after the resistor is connected in series. , the emitter output pin of the first optocoupler is electrically connected to the main microcontroller, and the collector of the first optocoupler is electrically connected to the positive pole of the power supply.

More preferably, the synchronous information extraction circuit includes the third and fourth current-limiting resistors, the second rectifier bridge, and the second photocoupler, the AC input terminal of the second rectifier bridge and the power supply line at the rear end of the power switch output terminal A third current-limiting resistor and a fourth current-limiting resistor are respectively connected in series between the zero and live wires, and the DC output terminal of the second rectifier bridge is electrically connected to the positive and negative poles of the input terminal of the second photocoupler after the resistors are connected in series, and the second photoelectric coupler The emitter output pin of the photocoupler is electrically connected to the slave microcontroller, and the collector pin of the second photocoupler is electrically connected to the positive pole of the power supply.

More preferably, the secondary power supply module is a switching power supply, and the switching power supply is provided with an energy storage element. The input terminal of the switching power supply is electrically connected to the zero and live wires of the power supply line at the rear end of the power switch output terminal, and the output terminal of the secondary power supply module is connected to the The slave microcontroller is electrically connected, and the energy storage element is used to ensure that the slave network controller works normally for a period of time when the power supply line is cut off.

More preferably, the power switch is a contactor, the normally open contact of the power switch is connected in series to one end of the power supply line connected to the power grid, and one end of the coil winding of the power switch is electrically connected to the zero line of the power supply line at the front end of the input end of the power switch. . The other end of the coil winding of the power switch is electrically connected with the live wire of the power supply line at the front end of the input end of the power switch after the drive control circuit is connected in series.

More preferably, the switch driving circuit includes an optocoupler, fifth and sixth resistors, a capacitor and a thyristor. The input end of the optocoupler is electrically connected to the power-off buffer circuit, the fifth and sixth resistors are connected in series between the first end of the output end of the optocoupler and the first main electrode of the thyristor, and the first end of the output end of the optocoupler Two terminals are electrically connected to the gate of the thyristor, one end of the capacitor is electrically connected to the second main electrode of the thyristor, and the other end of the capacitor is connected between the fifth and sixth resistors, one of the thyristor The coil winding of the power switch is connected in series between the main electrode and the neutral line of the power supply line at the front end of the power switch, and the other main electrode of the thyristor is electrically connected with the live wire of the power supply line at the front end of the power switch.

More preferably, the power-off buffer circuit includes a seventh resistor, a first and a second diode, a second capacitor, a third capacitor, a first and a second triode, an eighth, a ninth and a tenth resistor. One end of the seventh resistor is used as the power-on power transmission signal control end to be electrically connected to the microcontroller of the main network controller, and the other end of the seventh resistor is electrically connected to the base of the first triode, the second three The collector of the pole tube is electrically connected, the anode of the first diode is electrically connected, and the cathodes of the first and second diodes are connected in parallel as the power failure pulse signal control terminal for connecting the main microcontroller of the main network controller. The anode of the first diode is electrically connected to the base of the first triode and the collector of the second triode respectively, and the anode of the second diode is connected in series with the base of the second triode There is a ninth resistor, an eighth resistor is connected in series between the anode of the second diode and the collector of the first triode, and an eighth resistor is connected in series between the anode of the second diode and the emitter of the second triode There is a third capacitor, the emitter of the second triode is grounded, one end of the tenth resistor is connected in parallel with the positive pole of the second capacitor, and then electrically connected to the positive pole VDD of the power supply, and the negative pole of the second capacitor is grounded. An optocoupler is connected in series between the other end of the tenth resistor and the collector of the first triode for connection with the drive control circuit, and the emitter of the first triode is grounded.

The communication method of the online switch modulation digital communication control system of the local area power consumption network comprises the following steps:

Step 1, the main network controller obtains the control instruction, and the methods for obtaining the control instruction are: 1.1, transmit the control instruction to the microcontroller of the main network controller through the keyboard and display unit; 1.2, through the Internet of Things communication module, control The command is sent to the microcontroller of the main network controller through the computer or mobile phone;

Step 2, data modulation, specifically:

The main microcontroller controls the power switch to generate an instantaneous power failure pulse on the power supply line. The width of the power failure pulse represents the data length of the symbol. Because the pulse width is different, the corresponding data length of each symbol is also different. According to different codes The metadata length is used to encode information;

The main microcontroller converts the obtained control instructions into a set of code element data, and then compiles this set of code element data into driver programs that generate different instantaneous power failure pulse widths, and then the main microcontroller transmits the drive pulses to the drive control circuit;

Step 3, the drive control circuit of the main network controller controls the power switch according to the instructions of the main microcontroller to generate a group of instantaneous power failure pulses;

Step 4, data demodulation, specifically:

The slave network controller detects the instantaneous power failure pulse through the synchronous information extraction circuit, and transmits it to the slave microcontroller of the slave network controller through the emitter output pin of the second photocoupler, and the slave microcontroller of the slave network controller calculates the instantaneous The width of the blackout pulse;

The slave microcontroller of the slave network controller converts the detected single instantaneous power failure pulse information into a group of symbols with data information, and decodes it according to the preset communication protocol to generate control instructions;

Step 5, the slave microcontroller of the slave network controller sends the control command to the slave control unit, and the slave control unit generates PWM and switch control information according to the control command to realize the control of the electrical equipment.

The beneficial effects of the present invention are:

1. The invention achieves communication by generating instantaneous power failure pulses on the power supply line, which has the beneficial effect of simplifying power supply and communication lines;

2. The communication method of the invention has the beneficial effects of simple control, long transmission distance and no influence of line impedance;

3. The invention achieves the transmission of information by generating instantaneous power failure pulses, and has the beneficial effect of low power consumption;

4. The invention only needs to add a master-slave network controller on the power supply line, which has the beneficial effect of convenient installation and construction;

5. The present invention has the characteristics of strong practicability and wide application range, and can be used in fields such as intelligent lighting, intelligent home furnishing, and industrial automation control.

Description of drawings

Fig. 1 is the system structural diagram of the on-line switch modulation digital communication control system of the local power consumption network of the present invention,

Fig. 2 is the circuit structural diagram of the main network controller of the on-line switch modulation digital communication control system of the local power consumption network of the present invention,

Fig. 3 is the circuit structure diagram of the slave network controller of the online switch modulation digital communication control system of the local power consumption network of the present invention,

Fig. 4 is the circuit structural diagram of the power switch of the main network controller of the on-line switch modulation digital communication control system of the local power consumption network of the present invention, drive control circuit, power-off buffer circuit,

Fig. 5 is a schematic diagram of communication between the master-slave network controllers of the online switch modulation digital communication control system of the local power consumption network of the present invention.

In the picture:

1. Power supply line, 2. Main network controller, 21. Power switch, 22. Drive control circuit, 23. Grid synchronization signal extraction circuit, 24. Power-off buffer circuit, 25. Internet of Things communication module, 26. Keyboard, 27 Display unit, 3, slave network controller, 31, synchronous information input circuit, 32, slave control unit, 41, master microcontroller, 42, slave microcontroller, 51, master power module, 52, slave power module.

Detailed ways

In order to make the technical solutions and beneficial effects of the present invention clearer, the implementation manners of the present invention will be further explained in detail below.

As shown in FIG. 1 , the online switch modulation digital communication control system of the local power consumption network includes a master network controller 2 and a slave network controller 3 . The master and slave network controllers 2 and 3 are connected through the power supply line 1, and constitute a local power consumption network communication system. Preferably, the power supply line 1 is a single power supply network of AC 220V, including a neutral line and a live line. One end of the power supply line 1 is connected to the mains power supply grid. The main network controller 2 is installed on the power supply line 1 near the end of the mains power supply grid. There are multiple slave network controllers 3 and connected to the power supply line 1. The master and slave network controllers 2 and 3 can communicate through a local communication network formed by the master network controller 2 , the slave network controller 3 and the power supply line 1 .

The main network controller 2 is the center of the whole system and the sender of control commands. As shown in Figure 2, the main network controller 2 includes a power switch 21, a drive control circuit 22, a main microcontroller 41, a power-off buffer circuit 24, and an IoT communication module 25 and a keyboard 26 electrically connected to the main microcontroller 41 , a display unit 27 , a grid synchronization signal extraction circuit 23 , and a main power supply module 51 . In order to prevent the impact of the instantaneous power failure pulse on the main network controller 2, the main power module 51 is electrically connected to the zero and live wires of the power supply line 1 at the input end of the power switch 21, that is, the main power module 51 and the switching power supply 21 are close to the power supply of the power grid. Line 1 is electrically connected. The output end of the main power supply module 51 is electrically connected with the main microcontroller 41 to provide power for the main network controller 2 . The keyboard 26, display unit 27, and IoT communication module 25 electrically connected to the main microcontroller 41 of the main network controller 2 are used to obtain control instructions. The keyboard 26 and the display unit 27 are used to input instructions for data display, and the IoT communication module 25 is used to transfer instructions from the computer or mobile phone to the main microcontroller 41 of the main network controller 2 through communication. The Internet of Things communication module 25 is a communication module that connects the terminal equipment with the Internet, and transmits the information of the terminal equipment to the Internet so as to be controlled by mobile phones and computers.

The main network controller 2 of the system transmits the information to the slave network controller 3 connected to the power supply line 1 by generating an instantaneous power failure pulse with different pulse widths on the power supply line 1 as a carrier of information. Therefore, the main network controller 2 needs a controllable switching device installed on the power supply line 1 , and the switching device is the power switch 21 . Therefore, the power switch 21 is connected in series with one end of the power supply line 1 and the mains power supply network to realize the generation of instantaneous power failure pulses on the power supply line 1 . In the prior art, both contactors and relays can be used as the power switch 21 . With the development of power electronics technology, it is also a common way to realize on-off control by using components such as high-power two-phase thyristors and IGBTs.

More preferably, as shown in FIG. 4 , the power switch 21 uses a contactor to realize instantaneous power failure control. The contactor has normally closed and normally open contacts and coil windings. In order to realize power failure, the normally open contact of the control relay is connected in series between the mains power supply network and the power supply line 1, that is, all slave network controllers 3 are installed on the power supply line 1 at the rear end of the power switch 21 output. Preferably, the rated voltage of the coil winding of the contactor is AC 220V. Therefore, one end of the coil winding of the contactor is electrically connected to the neutral wire of the power supply line 1 on the power grid side of the power switch 21, and the other end is connected in series with the drive control circuit 22 and the live wire of the power supply line 1 on the power grid side of the power switch 21 is electrically connected. .

Since the power switch 21 is connected in series on the 220V power supply line 1, if the main microcontroller 41 directly controls the power switch 21, interference or even the phenomenon of burning of the main microcontroller 41 will occur, so the power switch 21 needs a drive control circuit 22 To achieve the isolation of strong and weak electricity. The drive control circuit 22 drives the power switch 21 according to the control command issued by the main microcontroller 41 to realize the on-off of the power supply line 1 .

Preferably, in order to control the power on and off of the contactor coil winding of the power switch 21 by the drive control circuit 22 , the drive control circuit 22 uses a thyristor SCR as a non-contact switch. In order to realize isolation from the 220V mains power supply network and ensure the safety of the main network controller 2 , an optocoupler V3 is provided in the drive control circuit 22 . The drive control circuit 22 also includes fifth and sixth resistors R5 and R6 and a capacitor C31. The input end of the optocoupler V3 is used for electrical connection with the main microcontroller 41 of the main network controller 2 . In the present invention, in order to ensure the safety of the slave network controller 3, the power-off buffer circuit 24 is connected in series between the main micro-controller 41 and the drive control circuit 22, so the input terminal of the optocoupler V3 and the power-off buffer circuit 24 Output electrical connection. There are fifth and sixth resistors R5 and R6 in series between the first end of the output end of the optocoupler V3 and the first main electrode of the thyristor SCR, and the second end of the output end of the optocoupler V3 is electrically connected to the gate electrode of the thyristor SCR. Connected to drive the SCR on and off. One end of the capacitor C31 is electrically connected to the connection point of the fifth and sixth resistors R5 and R6, and the other end of the capacitor C31 is electrically connected to the second main electrode of the thyristor SCR. The first and second main electrodes of the thyristor SCR are used to control the coil winding of the contactor of the power switch 21, that is, the first main electrode of the thyristor SCR is electrically connected to one end of the coil winding of the power switch 21, and the other main electrode Electrical connection with the power supply line 1 at the front end of the input end of the power switch 21.

Preferably, in order to verify whether the control instruction issued by the main network controller 2 is correct, a grid synchronization information extraction circuit 23 is set in the main network controller 2 . The power grid synchronization information extraction circuit 23 is used to collect and convert the instantaneous power failure pulse signal on the power supply line 1 and then transmit it to the main microcontroller 41 of the main network controller 2 for processing. The grid synchronization signal extraction circuit 23 includes a first current-limiting resistor R1, a second current-limiting resistor R2, a first rectifier bridge BD1, a first photocoupler V1, the AC input terminal of the first rectifier bridge BD1 and the power supply line 1 A first current-limiting resistor R1 and a second current-limiting resistor R2 are connected in series between the zero and live wires, and a resistor is connected in series between the DC output terminal of the first rectifier bridge BD1 and the positive and negative poles of the first photocoupler V1. The emitter output pin of the photocoupler V1 is electrically connected to the main microcontroller 41 of the main network controller 2 .

Due to the phenomenon of power failure in the power grid during the control process, due to the reclosing protection function of the power supply grid, there will be a phenomenon of power transmission immediately after power failure, and the short power failure interval of the power grid will cause the slave network controller 3 to have a power failure shutdown , and the restart of the slave network controller 3 requires a certain initialization time. In order to prevent the impact of the rapid re-energization of the grid on the restart of the slave network controller 3, the power switch 21 in the master network controller 2 is locked after the grid is powered off. After waiting for a certain period of time, power is sent to the power supply line 1 to protect the normal operation of the circuit from the network controller 3 . Therefore, the power-off buffer circuit 24 is connected in series between the drive control circuit 22 and the microcontroller 41 .

Preferably, the power-off buffer circuit 24 includes a seventh resistor R7, first and second diodes D1 and D2, a second capacitor C2, a third capacitor C3, first and second triodes Q1 and Q2, eighth, nine and ten Resistors R8, R9, R10.

One end of the seventh resistor R7 is used as a power-on power transmission signal control end for electrical connection with the main microcontroller 41 . The other end of the seventh resistor R7 is respectively connected to the base of the first transistor Q1 for driving the conduction of the first transistor Q1 . After the cathodes of the first and second diodes D1 and D2 are connected in parallel, they are used as the control terminal of the instantaneous power failure pulse signal for connecting to the main microcontroller 41 . The anode of the first diode D1 is electrically connected to the base of the first transistor Q1 and the collector of the second transistor Q2. A ninth resistor R9 is connected in series between the anode of the second diode D2 and the base of the second transistor Q2. An eighth resistor R8 is connected in series between the anode of the second diode D2 and the collector of the first triode Q1. A third capacitor C3 is connected in series between the anode of the second diode D2 and the emitter of the second transistor Q2. The emitter of the second transistor Q2 is grounded. The emitter of the first transistor Q1 is grounded. One end of the tenth resistor R10 is connected in parallel with the positive pole of the second capacitor C2 and then electrically connected to the positive pole VDD of the power supply. The negative pole of the second capacitor C2 is grounded. The other end of the tenth resistor R10 and the collector of the first transistor Q1 serve as the output end of the control signal. In this invention, the other end of the tenth resistor R10 and the collector of the first triode Q1 drive the optocoupler V3 of the control circuit 22 in series to drive the SCR in the control circuit 22 .

The main microcontroller 41 of the main network controller 2 is electrically connected to the input end of the power-off buffer circuit 24, the output end of the power-off buffer circuit 24 is electrically connected to the input end of the drive control circuit 22, and the output end of the drive control circuit 22 is electrically connected to the input end of the drive control circuit 22. The input end of the power switch 21 is electrically connected. It works as follows:

1. Startup from the network controller 3. It can be seen from the main network controller circuit diagram 4 of the power interruption buffer circuit 24 that when the power-on signal control terminal is at a high level, the first triode Q1 is turned on, the second triode Q2 is turned off, and the optocoupler V3 is driven to conduct. After the optocoupler V3 is turned on, the thyristor SCR is turned on, and the coil winding of the contactor of the power switch 21 is electrified to make the power switch 21 pull in, thereby electrifying the power supply line 1 and starting the slave network controller 3 .

2. From the protection of the network controller 3. Since the energy storage elements such as capacitors, inductors and chips in the slave network controller 3 need a certain period of time to discharge and reset after power-off, the slave network controller 3 can start to work normally. According to the circuit structure of the power-off buffer circuit 24 in FIG. 4 , it can be seen that when the shutdown signal occurs, that is, when the power-on signal control terminal changes from a high level to a low level, the power supply VDD is powered off. At this time, the electric energy stored in the capacitor C2 is discharged to the ground through the tenth resistor R10, the optocoupler V3, the eighth resistor R8, the ninth resistor R9, and the base of the second transistor Q2, and drives the second transistor Q2 to conduct. The base potential of the first triode Q1 is pulled down to lock the first triode Q1 to make it cut off. Since the optocoupler V3 is a current-driven type, the electric energy stored in the capacitor C2 passes through the resistance values of the eighth and ninth resistors R8 and R9 If the input current of the optocoupler V3 is too small, the output terminal of the optocoupler V3 will be cut off, and the triac loses the trigger signal and the cut-off control power switch 21 is released. The base potential of the transistor Q1 is turned on and pulled down to lock by the second transistor Q2, so it cannot be turned on for a period of time, which plays a role in protecting the network controller 3 from being powered off and reset. After the capacitor C2 is completely discharged, the second transistor Q2 is turned on and turned off, and the base of the first transistor Q1 is unlocked. Therefore, it prevents personnel from continuously pressing the start button and the influence of reclosing on the slave network controller 3 after the power supply network is powered off.

3. Generation of instantaneous power failure pulses. When the power-on signal control terminal in the power-off buffer circuit 24 is at a high level, the power switch 21 is in a closed state. When the momentary power failure pulse signal occurs, the control terminal of the main micro-controller 41 outputs a low-level pulse signal through the first and second diodes D1 and D2, so the voltage at the base of the first triode Q1 is pulled down to make the second A triode Q1 is turned off, and the drive control circuit 22 controls the power switch 21 to turn off, that is, the instantaneous power failure pulse starts. At the same time, due to the action of the second diode D2, the voltage of the base of the second transistor Q2 is pulled down, so that the second transistor Q2 is turned off, and the power-off protection function is effectively released during the power-off pulse. At the end of the pulse, the control terminal of the main micro-controller 41 turns on the first triode Q1 when the output of the first and second diodes D1 and D2 changes from a low level to a high level, and controls the drive control circuit 22 bidirectional thyristor SCR Turn on and drive the power switch 21 to pull in, and complete a process of generating an instantaneous power failure pulse. The instantaneous power failure pulse time is more than ten milliseconds.

The master network controller 2 is used to send data or control instructions, and the slave network controller 3 is used to receive data and control instructions. As shown in FIG. 3 , the slave network controller 3 includes a slave microcontroller 42 , a synchronization information extraction circuit 31 , a slave power module 52 , and a slave control unit 32 . The slave microcontroller 42 and the slave power module 52 are basic circuits that the slave network controller 3 operates. The synchronous information extraction circuit 31 is used to collect and convert the instantaneous power failure pulse signal on the power supply line 1 and transmit it to the slave microcontroller 42 . The slave control unit 32 is used to execute control commands obtained from the network controller 3 on the power supply line 1 .

Preferably, the synchronous information extraction circuit 31 includes the third and fourth current limiting resistors R3, R4, the second rectifier bridge BD2, the second photocoupler V2, the AC input terminal of the second rectifier bridge BD2 and the zero of the power supply line A third current-limiting resistor R3 and a fourth current-limiting resistor R4 are respectively connected in series between the live wire and the live wire, and a resistor is connected in series between the DC output terminal of the second rectifier bridge BD2 and the positive and negative poles of the second photocoupler V2 to provide the first The second photocoupler V2 limits the current. The emitter output pin of the second photocoupler V2 is electrically connected to the slave microcontroller 42 of the slave network controller 3 , so as to transmit the instantaneous power failure pulse signal to the slave microcontroller 42 for data processing.

Better, in order to prevent the slave network controller 3 from powering off when the instantaneous power failure pulse is generated, the slave power supply module 52 of the slave network controller 3 has a switching power supply with an energy storage element. The input end of the slave power module 52 is electrically connected with the zero and live wires of the power supply line 1 at the rear end of the output end of the power switch 21 , and the output end of the slave power module 52 is electrically connected with the slave microcontroller 42 . The energy storage element is used to ensure that the slave network controller 3 can work normally when the power supply line 1 is cut off. Even better, in the prior art, the more commonly used energy storage element is an electrolytic capacitor, and the two electrodes of the electrolytic capacitor are connected to the output terminal of the switching power supply in parallel. When the alternating current of the switching power supply loses power, the electric energy stored in the electrolytic capacitor Power is supplied to each component in the slave network controller 3 . The data transmission mode of the control system is not only applied in the AC power distribution network, but also can be applied in the DC power supply network.

The above is the description of the structure of the online switch modulation digital communication control system of the local power consumption network, and the specific method for realizing communication between the master and slave network controllers 2 and 3 of the system will be described below. As shown in Figure 5, its method includes the following steps:

Step 1. The main network controller 2 acquires a control instruction. The methods for obtaining control instructions are:

1.1, control commands are input into the main microcontroller 41 of the main network controller 2 through the keyboard 26 and the display unit 27;

1.2, through the Internet of Things communication module 25, the control command is sent to the main microcontroller 41 of the main network controller 2 through a computer or a mobile phone;

Step 2. Data modulation. Specifically:

The main microcontroller 41 controls the power switch 21 to generate a single instantaneous power failure pulse on the power supply line 1. The width of the power failure pulse represents the data length of the symbol. Because the pulse width is different, the corresponding data length of each symbol is also different. Different symbol data lengths are used to encode information;

The main microcontroller 41 converts the obtained control instructions into a group of symbol data, and then converts this group of symbol data into driver programs that generate different instantaneous power failure pulses, and then the main microcontroller 41 transmits the drive pulses to the drive control circuit twenty two.

Step 3, the driving control circuit 22 of the main network controller 2 controls the power switch 21 to generate instantaneous power failure pulse information on the power supply line 1 according to the instruction of the main microcontroller 41 .

Step 4, data demodulation. Specifically:

Slave network controller 3 detects instantaneous power failure pulse by synchronous information extracting circuit 31, and passes to slave microcontroller 42 of network controller 3 by the emitter output pin of the second optocoupler V2, from network controller 3 Calculate the width of the momentary power failure pulse from microcontroller 42;

From the microcontroller (42) of the network controller (3), the detected single instantaneous power failure pulse information is converted into a group of symbols with data information, and decoded according to a preset communication protocol to generate control instructions;

Step 5, the slave microcontroller 42 of the network controller 3 sends the control command to the slave control unit 32, and the slave control unit 32 generates PWM and switch control information according to the control command and controls the electrical equipment.

In summary, it is only a preferred embodiment of the present invention, and it is not used to limit the scope of the present invention. Through the above description, relevant workers can perform various tasks without departing from the scope of the technical idea of the present invention. changes and modifications. The technical scope of the present invention is not limited to the contents of the description, and all so-called equivalent changes and modifications in terms of shape, structure, features and spirit described in the scope of the claims of the present invention shall be included in the scope of the claims of the present invention.

Claims (7)

1. The local power utilization network on-line switch modulation digital communication control system is characterized in that:

comprises a master network controller (2) and a slave network controller (3),

the main network controller (2) comprises a power switch (21), a driving control circuit (22), a main microcontroller (41), a power-off buffer circuit (24), an Internet of things communication module (25), a keyboard (26), a display unit (27), a power grid synchronous signal extraction circuit (23) and a main power module (51) which are electrically connected with the main microcontroller (41),

the power switch (21) is connected in series in the power supply circuit (1), a power-off buffer circuit (24) is connected in series between the input end of the drive control circuit (22) and the main microcontroller (41), the output end of the drive control circuit (22) is electrically connected with the control end of the power switch (21), the main power module (51) is electrically connected with the power supply circuit (1) of the power grid end of the input end of the power switch (21), the power grid synchronous signal extraction circuit (23) is electrically connected with the power supply circuit (1) of the rear end of the output end of the power switch (21),

the slave network controller (3) comprises a slave microcontroller (42), a synchronous information extraction circuit (31), a slave power module (52) and a slave control unit (32), wherein the slave microcontroller (42) is electrically connected with the synchronous information extraction circuit (31), the slave power module (52) and the slave control unit (32), and the synchronous information extraction circuit (31) and the slave power module (52) are electrically connected with a power supply circuit (1) at the rear end of the output end of the power switch (21);

the power-off buffer circuit (24) comprises a seventh resistor (R7), a first diode (D1), a second diode (D2), a second capacitor (C2), a third capacitor (C3), a first triode (Q1), a second triode (Q2), an eighth resistor, a ninth resistor and a tenth resistor (R8, R9 and R10),

one end of the seventh resistor (R7) is used as a power-on power transmission signal control end and is electrically connected with a main microcontroller (41) of the main network controller (2), the other end of the seventh resistor (R7) is electrically connected with a base electrode of the first triode (Q1), a collector electrode of the second triode (Q2) and an anode of the first diode (D1), cathodes of the first and second diodes (D1 and D2) are connected in parallel and serve as power failure pulse signal control ends and are used for being connected with a main microcontroller (41) of the main network controller (2), an anode of the first diode (D1) is electrically connected with a base electrode of the first triode (Q1) and a collector electrode of the second triode (Q2), a ninth resistor (R9) is connected between an anode of the second diode (D2) and a collector electrode of the first triode (Q1) in series, an eighth resistor (R8) is connected between an anode of the second diode (D2) and a collector electrode of the second triode (Q2) in series, an anode of the second diode (D2) and a cathode of the second diode (C2) are connected with a capacitor of the second triode (Q2) in series, and a capacitor of the second triode (Q2) is connected with the anode of the second diode (C2) in series, and a capacitor of the second triode (C2) is connected with the ground, and the capacitor of the second triode (C2) is connected with the capacitor (C2 in series, and a optocoupler (V3) is connected in series between the other end of the tenth resistor (R10) and the collector electrode of the first triode (Q1) and is used for controlling a driving control circuit (22), and the emitter electrode of the first triode (Q1) is grounded.

2. The local area power-on-line switch-modulated digital communication control system of claim 1, wherein:

the power supply line (1) is an alternating current power supply grid.

3. The local area power-on-line switch-modulated digital communication control system of claim 1, wherein:

the power grid synchronous signal extraction circuit (23) comprises a first current limiting resistor (R1), a second current limiting resistor (R2), a first rectifying bridge (BD 1) and a first photoelectric coupler (V1), wherein the first current limiting resistor (R1) and the second current limiting resistor (R2) are respectively connected in series between an alternating current input end of the first rectifying bridge (BD 1) and zero and fire wires of a power supply circuit (1) at the rear end of an output end of a power switch (21), a direct current output end of the first rectifying bridge (BD 1) is connected with an anode and a cathode of an input end of the first photoelectric coupler (V1) in series, an emitter output pin of the first photoelectric coupler (V1) is electrically connected with a main microcontroller (41), and a collector of the first photoelectric coupler (V1) is electrically connected with a positive electrode of a power supply.

4. The local area power-on-line switch-modulated digital communication control system of claim 1, wherein:

the synchronous information extraction circuit (31) comprises a third current limiting resistor (R3) and a fourth current limiting resistor (R4), a second rectifying bridge (BD 2) and a second photoelectric coupler (V2), wherein the third current limiting resistor (R3) and the fourth current limiting resistor (R4) are respectively connected in series between an alternating current input end of the second rectifying bridge (BD 2) and a zero line and a fire line of a power supply circuit (1) at the rear end of an output end of a power switch (21), a direct current output end of the second rectifying bridge (BD 2) is connected with an anode and a cathode of an input end of the second photoelectric coupler (V2) after being connected with the resistors in series, and an emitter output pin of the second photoelectric coupler (V2) is electrically connected with a slave microcontroller (42), and a collector pin of the second photoelectric coupler (V2) is electrically connected with a power supply anode.

5. The local area power-on-line switch-modulated digital communication control system of claim 1, wherein:

the secondary power supply module (52) is a switching power supply, the switching power supply is provided with an energy storage element, the input end of the switching power supply is electrically connected with zero and live wires of a power supply circuit (1) at the rear end of the output end of a power switch (21), the output end of the secondary power supply module (52) is electrically connected with a secondary microcontroller (42), and the energy storage element is used for ensuring normal operation of the secondary network controller (3) at the moment when the power supply circuit (1) is powered off.

6. The local area power-on-line switch-modulated digital communication control system of claim 1, wherein:

the power switch (21) is a contactor, a normally open contact of the power switch (21) is connected in series with one end of the power supply circuit (1) connected with a power grid, one end of a coil winding of the power switch (21) is electrically connected with a zero line of the power supply circuit (1) at the front end of the power switch (21), and the other end of the coil winding of the power switch (21) is connected in series with a drive control circuit (22) and then electrically connected with a live wire of the power supply circuit (1) at the front end of the power switch (21).

7. The communication method of a local area network on-line switch modulation digital communication control system according to claim 1, characterized by comprising the steps of:

step 1, a main network controller (2) acquires a control instruction, and the method for acquiring the control instruction comprises the following steps:

1.1, transmitting control instructions to a main microcontroller (41) of a main network controller (2) through a keyboard (26) and a display unit (27);

1.2, sending a control instruction to a main microcontroller (41) of the main network controller (2) through a computer or a mobile phone by an Internet of things communication module (25);

step 2, data modulation, specifically:

the main microcontroller (41) controls the power switch (21) to generate an instantaneous power-off pulse on the power supply line (1), the width of the power-off pulse represents the data length of a code element, the data length of each corresponding code element is different because the pulse width is different, and information is encoded according to the different code element data lengths;

the main microcontroller (41) converts the obtained control instruction into a group of code metadata, then compiles the group of code metadata into a driving program for generating different instantaneous power failure pulse widths, and the main microcontroller (41) transmits the driving pulse to the driving control circuit (22);

step 3, a drive control circuit (22) of the main network controller (2) controls a power switch (21) to generate a group of instantaneous power failure pulses according to the instruction of the main microcontroller (41);

and 4, data demodulation, specifically:

the slave network controller (3) detects the instantaneous power failure pulse through the synchronous information extraction circuit (31) and transmits the instantaneous power failure pulse to the slave microcontroller (42) of the slave network controller (3) through the emitter output pin of the second photoelectric coupler (V2), and the slave microcontroller (42) of the slave network controller (3) calculates the width of the instantaneous power failure pulse;

the slave microcontroller (42) of the slave network controller (3) converts a group of detected instantaneous power failure pulse information into a group of code elements with data information, decodes the code elements according to a preset communication protocol and generates a control instruction;

and step 5, a slave microcontroller (42) of the slave network controller (3) sends a control instruction to the slave control unit (32), and the slave control unit (32) generates PWM and switch control information according to the control instruction to control the electric equipment.

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