Smart electric meter and control method

Abstract

The invention discloses an intelligent electric meter and a control method, and relates to the technical field of electric energy meters, the intelligent electric meter is connected with a master station, and the intelligent electric meter comprises a control module, a first isolation calibration module, a second isolation calibration module and a communication module; the communication module is connected with a master station; the first isolation calibration module is respectively connected with the communication module and the control module, the first isolation calibration module is used for sending a first communication signal output by a master station to the control module in an isolated manner, and the first isolation calibration module performs bit width calibration on the first communication signal; the second isolation calibration module is respectively connected with the communication module and the control module, the second isolation calibration module is used for sending a second communication signal output by the control module to the master station in an isolated manner, and the second isolation calibration module is also used for carrying out bit width calibration on the second communication signal. The problem that the interference resistance of 115200bps communication realized based on isolation high-speed communication devices such as a capacitive coupler, a magnetic coupler and a high-speed optical coupler in the related technology is weak, so that the isolation high-speed communication devices are damaged is solved.

Description

Technical Field

[0001] The present application relates to the technical field of electric energy meters, and in particular to smart electric meters and control methods. Background Art

[0002] With the widespread adoption of smart energy, electricity meters are becoming increasingly complex, requiring more data to be stored and transmitted. Communication rates are gradually being replaced by 115,200 bps instead of 9,600 bps to improve overall system efficiency and performance. Both module and RS485 communication require electrical isolation from internal circuitry, so isolating high-speed communication devices is key to achieving 115,200 bps communication.

[0003] Currently, there are mainly isolated high-speed communication devices such as capacitive coupling, magnetic coupling, and high-speed optocouplers. The isolated communication principle of these devices determines the high degree of integration within the devices. Therefore, compared with ordinary optocouplers, their anti-interference ability is greatly weakened. Whether it is a module interface or an RS485 interface, it is very easy to introduce external interference, resulting in damage to the isolated high-speed communication devices. Summary of the Invention

[0004] The present application provides a smart meter and a control method to at least solve the problem in the related art that the 115200bps communication implemented based on isolated high-speed communication devices such as capacitive coupling, magnetic coupling, and high-speed optical coupling has weak anti-interference ability, resulting in damage to the isolated high-speed communication devices.

[0005] The present application provides a smart meter, which is connected to a master station and includes: a control module, a first isolation calibration module, a second isolation calibration module, and a communication module;

[0006] The communication module is connected to the master station;

[0007] The first isolation calibration module is connected to the communication module and the control module respectively, and is used to isolate the first communication signal output by the master station and send it to the control module. The first isolation calibration module is also used to perform bit width calibration on the first communication signal;

[0008] The second isolation calibration module is connected to the communication module and the control module respectively. The second isolation calibration module is used to isolate the second communication signal output by the control module and send it to the master station. The second isolation calibration module is also used to perform bit width calibration on the second communication signal.

[0009] The present application uses a control module to isolate and perform bit width self-calibration based on the first isolation calibration module and the second isolation calibration module during the communication process with the master station. Compared with the traditional ordinary optocoupler, when performing 115200bps communication, the bit width between the high level and the low level is unbalanced due to the excessively fast communication rate, thus causing the problem of communication failure. The present application performs real-time bit width calibration according to the current bit width state, achieves bit width balance between the high level and the low level, and greatly improves the stability of transmission. Furthermore, by achieving 115200bps communication through ordinary optocouplers, the anti-interference performance is not weakened compared to circuits composed of isolated high-speed communication devices such as capacitive coupling, magnetic coupling, and high-speed optocouplers.

[0010] In some optional embodiments, the first isolation calibration module includes:

[0011] a first isolated communication circuit, the first isolated communication circuit being connected to the master station and configured to isolate and output the first communication signal;

[0012] a first adjustment circuit, the first adjustment circuit being connected to the first isolated communication circuit and the control module respectively, for receiving a first communication signal, performing waveform adjustment on the first communication signal, and then outputting the waveform to the control module;

[0013] The control module is further configured to receive the first communication signal and output a first calibration signal when detecting that the first bit width deviation data of the first communication signal is greater than a first preset bit width deviation threshold;

[0014] A first calibration circuit is connected to the first adjustment circuit and the control module respectively, and is used to receive the first calibration signal and perform bit width calibration on the first adjustment circuit.

[0015] In some optional embodiments, the second isolation calibration module includes:

[0016] a second isolated communication circuit, connected to the control module and configured to isolate and output the second communication signal;

[0017] a second adjustment circuit, the second adjustment circuit being connected to the second isolated communication circuit and the master station respectively, for receiving a second communication signal, performing waveform adjustment on the second communication signal, and outputting the waveform to the master station;

[0018] The master station receives the second communication signal and outputs calibration data when detecting that the second bit width deviation data of the second communication signal is greater than a second preset bit width deviation threshold;

[0019] The control module is further configured to receive the calibration data and output a second calibration signal;

[0020] an isolation calibration control circuit, connected to the control module, configured to receive the second calibration signal and output it in isolation;

[0021] The second calibration circuit is connected to the second adjustment circuit and the isolation calibration control circuit respectively, and the second calibration circuit is used to isolate and receive the second calibration signal and perform bit width calibration on the second adjustment circuit.

[0022] In some optional implementations, the first calibration circuit is configured to receive a first calibration signal and control a first impedance corresponding to the first calibration signal to be connected to the first adjustment circuit, so as to perform bit width calibration on the first adjustment circuit.

[0023] In some optional implementations, the first calibration circuit includes:

[0024] a first selection unit, the first selection unit being connected to the control module;

[0025] a plurality of first resistors, wherein first ends of the plurality of first resistors are connected to the first selection unit, and second ends of the plurality of first resistors are connected to the first adjustment circuit, wherein resistance values ​​of the plurality of first resistors are different;

[0026] The first selection unit is configured to receive a first calibration signal and control a target first resistor corresponding to the first calibration signal to be connected to a ground terminal and the first adjustment circuit respectively.

[0027] In some optional implementations, the isolation calibration control circuit includes:

[0028] An optical coupling unit, wherein a first end of the optical coupling unit is connected to the control module, and a second end of the optical coupling unit is connected to the second calibration circuit.

[0029] In some optional implementations, the second calibration circuit is configured to receive a second calibration signal and control a second impedance corresponding to the second calibration signal to be connected to the second adjustment circuit, so as to perform bit width calibration on the second adjustment circuit.

[0030] In some optional implementations, the second calibration circuit includes:

[0031] a second selection unit connected to the isolation calibration control circuit;

[0032] a plurality of second resistors, wherein first ends of the plurality of second resistors are connected to the second selection unit, and second ends of the plurality of second resistors are connected to the second adjustment circuit, wherein resistance values ​​of the plurality of second resistors are different;

[0033] The second selection unit is configured to receive a second calibration signal and control a target second resistor corresponding to the second calibration signal to be connected to the ground terminal and the second adjustment circuit respectively.

[0034] The present application also provides a control method for a smart meter, which is applied to the smart meter as described above, and includes:

[0035] Upon receiving the calibration command from the first isolation calibration module, confirming the first bit width deviation data of the calibration command from the first isolation calibration module, and detecting whether the first bit width deviation data is greater than a first preset bit width deviation threshold;

[0036] If it is confirmed that the first bit width deviation data is greater than the first preset bit width deviation threshold, controlling the first isolation calibration module to perform calibration corresponding to the first bit width deviation data;

[0037] and / or;

[0038] outputting a test signal upon receiving a calibration command from the second isolation calibration module;

[0039] Second bit width deviation data is received, and a second isolation calibration module is controlled to perform calibration corresponding to the second bit width deviation data, wherein the second bit width deviation data is output by the master station based on the test signal.

[0040] In some optional embodiments,

[0041] detecting whether the received command is a calibration command of the first isolation calibration module;

[0042] If it is not a calibration command of the first isolated calibration module, detecting whether the command is a calibration command of the second isolated calibration module;

[0043] If it is not the calibration command of the second isolation calibration module, it is determined to be the second bit width deviation data. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0045] Figure 1A structural diagram of a smart meter provided in an embodiment of the present application;

[0046] Figure 2 A structural diagram of another smart meter provided in an embodiment of the present application;

[0047] Figure 3 A structural diagram of another smart meter provided in an embodiment of the present application;

[0048] Figure 4 A flowchart of a control method for a smart meter provided in an embodiment of the present application. DETAILED DESCRIPTION

[0049] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0050] It should be noted that, in the description of this application, the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. The terms "first," "second," etc., in this application are used to distinguish similar objects, and are not used to describe a particular order or sequence.

[0051] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0052] In conjunction with the specific application environment architecture or specific hardware architecture on which the execution of the control method of the smart meter depends, the specific application environment architecture or specific hardware architecture is described here.

[0053] With the widespread adoption of smart energy, electricity meters are becoming increasingly complex, requiring more data to be stored and transmitted. Communication rates are gradually being replaced by 115,200 bps instead of 9,600 bps to improve overall system efficiency and performance. Both module and RS485 communication require electrical isolation from internal circuitry, so isolating high-speed communication devices is key to achieving 115,200 bps communication.

[0054] Currently, there are mainly isolated high-speed communication devices such as capacitive coupling, magnetic coupling, and high-speed optocouplers. The isolated communication principle of these devices determines the high degree of integration within the devices. However, compared with ordinary optocouplers, their anti-interference ability is greatly weakened. Whether it is a module interface or an RS485 interface, it is very easy to introduce external interference, resulting in damage to the isolated high-speed communication devices.

[0055] The embodiment of the present application provides a smart meter, such as Figure 1 Said smart meter is connected to the master station, and said smart meter comprises: a control module 30, a first isolation calibration module 10, a second isolation calibration module 20 and a communication module 40;

[0056] The communication module 40 is connected to the master station;

[0057] The first isolation calibration module 10 is connected to the communication module 40 and the control module 30 respectively. The first isolation calibration module 10 is used to isolate the first communication signal output by the master station and send it to the control module 30. The first isolation calibration module 10 is also used to perform bit width calibration on the first communication signal;

[0058] The second isolation calibration module 20 is connected to the communication module 40 and the control module 30 respectively. The second isolation calibration module 20 is used to isolate the second communication signal output by the control module 30 and send it to the master station. The second isolation calibration module 20 is also used to perform bit width calibration on the second communication signal.

[0059] Specifically, refer to Figure 1 The smart meter also includes a communication module 40, which is connected to the first isolation calibration module 10, the second isolation calibration module 20, and the master station, respectively. The communication module 40 is used to convert the first communication signal sent by the master station and send it to the first isolation calibration module 10. It is also used to convert the second communication signal sent by the second isolation calibration module 20 and send it to the master station. The communication module 40 can specifically be module communication or RS485 communication. The communication module 40 converts the command frame or data frame sent by the master station from the RS485 communication signal to a CMOS signal. The communication module 40 converts the CMOS signal sent by the control module into an RS485 communication signal. Thus, the communication module 40 realizes signal conversion between the master station and the control module 30.

[0060] For example, refer to Figure 3Communication module 40 is an RS485 communication module, specifically including a control chip U3, a thermistor RT1, a third capacitor C3, a twentieth resistor R20, a first transient suppression diode D1, a second transient suppression diode D2, and a third transient suppression diode D3. The first transient suppression diode D1, the second transient suppression diode D2, and the third transient suppression diode D3 are used for anti-static protection. P1 and P2 are connected to the master station. Control chip U3 converts RS485 communication signals into CMOS signals and outputs them through pin 1. Pin 4 of control chip U3 inputs output data from control module 30, including response frames or test frames. Furthermore, control module 30 isolates and controls control chip U3 from receiving or sending data through a third optocoupler OC3, a tenth resistor R10, and an eleventh resistor R11.

[0061] Specifically, the master station is specifically a master station system. The control module 30 is a computing MCU. The first isolation calibration module 10 is used to isolate and transmit the first communication signal sent by the master station to the control module 30, and perform self-calibration during the transmission of the first communication signal. During calibration, the control module 30 confirms the first bit width data based on the received first communication signal and determines whether bit width calibration is required based on the first bit width data. If bit width calibration is not required, no operation is performed. If bit width calibration is required, the first isolation calibration module 10 is controlled to perform bit width calibration.

[0062] Specifically, the second isolation calibration module 20 is used to isolate and transmit the second communication signal sent by the control module 30 to the master station, and to perform self-calibration during the transmission of the second communication signal. During calibration, the master station confirms the second bit-width data based on the second communication signal sent by the control module 30 to the master station, and determines whether bit-width calibration is required based on the second bit-width data. If bit-width calibration is not required, no operation is performed. If bit-width calibration is required, a calibration command is sent to the control module 30. The control module 30 controls the second isolation calibration module 20 to perform bit-width calibration based on the calibration command.

[0063] Optionally, the first isolation calibration module 10 and the second isolation calibration module 20 are modules for adjusting waveforms based on control signals and performing isolated transmission.

[0064] The present application uses the control module 30 to isolate and perform bit width self-calibration based on the first isolation calibration module 10 and the second isolation calibration module 20 during the communication process with the master station. Compared with the traditional ordinary optocoupler that is unable to communicate due to the imbalance of bit width between high level and low level due to the excessively fast communication rate during 115200bps communication, the present application performs real-time bit width calibration based on the current bit width state, achieves bit width balance between high level and low level, and greatly improves the stability of transmission. Furthermore, 115200bps communication can be achieved through ordinary optocouplers, and compared with circuits composed of isolated high-speed communication devices such as capacitive coupling, magnetic coupling, and high-speed optocouplers, the anti-interference performance is not weakened.

[0065] In addition, for example, assuming that under normal circumstances, the low-level bit width is 1s and the high-level bit width is also 1s, because the communication rate exceeds the upper limit of ordinary optocouplers, the low-level output of the optocoupler may become 1.9s and the high-level becomes 0.1s. Through the shaping circuit, the low level may become 1.1s and the high level becomes 0.9s; due to the discreteness of the optocoupler, the low-level and high-level outputs of the optocoupler may also be 1.8s, 0.2s or 1.7s, 0.3s, and the output of the shaping circuit will also change accordingly. Therefore, the smart meter of this application document separately adjusts the shaping circuit to make the high and low levels of the shaping output as much as possible 1s. In theory, it can correctly identify the reception of 1s±0.4s. By adjusting it to 1s±0.1s through the first isolation calibration module 10 and the second isolation calibration module 20, the probability of correct identification by the receiver is higher.

[0066] In some optional embodiments, such as Figure 2 and Figure 3 As shown, the first isolation calibration module 10 includes:

[0067] A first isolated communication circuit 11, the first isolated communication circuit 11 is connected to the master station, and the first isolated communication circuit 11 is used to isolate and output the first communication signal;

[0068] Specifically, the first isolated communication circuit 11 is used to isolate the communication module 40 from the control module 30, thereby improving interference resistance. The first isolated communication circuit 11 also performs level conversion, converting the 5V level to a 3.3V level. It is worth noting that due to the rate limit of 115200bps communication, the first communication signal is converted from a rectangular wave to a triangular wave.

[0069] Exemplarily, the first isolated communication circuit 11 includes a first optocoupler OC1 and a sixth resistor, wherein the first reference voltage V485 is 5V, the second reference voltage VCC is 3.3V, and the first optocoupler OC1 performs isolation and level conversion and outputs the result through pin 3 of the first optocoupler OC1.

[0070] a first adjustment circuit 12, the first adjustment circuit 12 being connected to the first isolated communication circuit 11 and the control module 30, respectively, for receiving a first communication signal, performing waveform adjustment on the first communication signal, and outputting the waveform to the control module;

[0071] Specifically, the first adjustment circuit 12 is a shaping circuit, that is, used to convert a triangular wave into a rectangular wave and then transmit the rectangular wave to the control module 30 .

[0072] Exemplarily, the first adjustment circuit 12 includes a first transistor Q1, a third resistor R3 and a fifth resistor R5. A triangular wave signal is input through pin 2 of the third resistor R3. After conversion by the first transistor Q1, a rectangular wave signal is output from pin 2 of the first transistor Q1 and input into the control module 30.

[0073] The control module 30 is further configured to receive the first communication signal and output a first calibration signal when detecting that the first bit width deviation data of the first communication signal is greater than a first preset bit width deviation threshold;

[0074] Specifically, the first communication signal includes a calibration command for the first adjustment circuit 12, and the first bit width deviation data is specifically the first low-level bit width deviation time of the calibration command for the first adjustment circuit 12. The control module 30 receives the first communication signal and detects the first low-level bit width deviation time between the first low-level bit width time of the first communication signal and a first preset low-level bit width time. If the first low-level bit width deviation time is greater than the first preset bit width deviation threshold, the control module 30 outputs the first calibration signal and the first response frame to the master station. The response path to the master station can pass through the second isolation calibration module. At this point, the master station continues to send the first communication signal, and this cycle continues until the control module 30 responds to the master station that no calibration is required.

[0075] In addition, in addition to the method of detecting by the time of the low level, the method of detecting by the time of the high level may also be included.

[0076] If it is detected that the first low-level bit width deviation time is less than or equal to the first preset bit width deviation threshold, no calibration is required.

[0077] The first calibration circuit 13 is connected to the first adjustment circuit 12 and the control module 30 respectively. The first calibration circuit 13 is used to receive the first calibration signal and perform bit width calibration on the first adjustment circuit 12 .

[0078] Specifically, the first calibration circuit 13 performs adjustment on the first adjustment circuit 12 based on the first calibration signal, so as to perform bit width calibration on the first adjustment circuit.

[0079] It is worth noting that the first communication signal refers to the data sent by the master station to the control module 30 .

[0080] In some optional embodiments, Figure 2 As shown, the second isolation calibration module 20 includes:

[0081] A second isolated communication circuit 21, connected to the control module 30, for isolating and outputting the second communication signal;

[0082] Specifically, the second isolated communication circuit 21 is used to isolate the communication module 40 from the control module 30, thereby improving interference resistance. The second isolated communication circuit 21 also performs level conversion, converting the 3.3V level to the 5V level. It is worth noting that due to the rate limit of 115200bps communication, the second communication signal is converted from a rectangular wave to a triangular wave.

[0083] Exemplarily, the second isolated communication circuit 21 includes a second optical coupler OC2 and a twelfth resistor R12. Pin 2 of the second optical coupler OC2 inputs the response frame or test frame of the control module, and the second optical coupler OC2 outputs the CMOS signal from pin 3 after electrical isolation and level conversion.

[0084] a second adjustment circuit 22, the second adjustment circuit 22 being connected to the second isolated communication circuit 21 and the master station, respectively, for receiving a second communication signal, performing waveform adjustment on the second communication signal, and outputting the signal to the master station;

[0085] Specifically, the second adjustment circuit 22 is a shaping circuit, that is, used to convert the triangular wave into a rectangular wave and then transmit it to the master station.

[0086] Illustratively, the second adjustment circuit 22 includes a second transistor Q2, a fourth resistor R4 and a thirteenth resistor R13. Pin 2 of the second adjustment circuit 22 inputs a triangular wave signal, which is converted by the second transistor Q2 and then output from pin 2 of the second transistor Q2.

[0087] The master station receives the second communication signal and outputs calibration data when detecting that the second bit width deviation data of the second communication signal is greater than a second preset bit width deviation threshold;

[0088] Specifically, the master station outputs a calibration command for the second adjustment circuit 22, and the control module outputs a second communication signal based on the calibration command for the second adjustment circuit 22. The second communication signal includes a test frame output by the control module 30, and the second bit width deviation data is specifically the second low-level bit width deviation time of the test frame. The master station receives the second communication signal and detects the second low-level bit width deviation time between the second low-level bit width time of the second communication signal and the second preset low-level bit width time. If it is detected that the second low-level bit width deviation time is greater than the second preset bit width deviation threshold, the calibration data is output. If it is detected that the second low-level bit width deviation time is less than or equal to the second preset bit width deviation threshold, no calibration is required, and thus no calibration data is output. After the control module 30 calibrates the second adjustment circuit 22, it outputs a second response frame. The master station continues to detect whether calibration is still required based on the second response frame, and repeats this cycle until the test frame received by the master station does not require calibration.

[0089] The control module 30 is further configured to receive the calibration data and output a second calibration signal;

[0090] an isolation calibration control circuit 23, connected to the control module 30, configured to receive the second calibration signal and output it in isolation;

[0091] Specifically, since the control module 30 performs adjustments on the isolated second adjustment circuit, the second calibration signal output by the control module 30 also needs to be isolated from the control module 30 , thereby improving anti-interference performance.

[0092] The second calibration circuit 24 is connected to the second adjustment circuit 22 and the isolation calibration control circuit 23 respectively. The second calibration circuit 24 is used to isolate and receive the second calibration signal and perform bit width calibration on the second adjustment circuit.

[0093] Specifically, the second calibration circuit 24 performs adjustment on the second adjustment circuit 22 based on the second calibration signal, so as to perform bit width calibration on the second adjustment circuit.

[0094] It is worth noting that the second communication signal refers to the data sent by the control module 30 to the master station.

[0095] In some optional embodiments, Figure 2 As shown, the first calibration circuit 13 is used to receive a first calibration signal and control a first impedance corresponding to the first calibration signal to be connected to the first adjustment circuit, so as to perform bit width calibration on the first adjustment circuit.

[0096] Specifically, the first calibration circuit 13 receives the first calibration signal and connects the first impedance corresponding to the first calibration signal to the first adjustment circuit, thereby adjusting the bit width of the waveform output by the first adjustment circuit.

[0097] In some optional embodiments, Figure 3 As shown, the first calibration circuit 13 includes:

[0098] A first selection unit U1, the first selection unit U1 is connected to the control module 30;

[0099] a plurality of first resistors R1, wherein first ends of the plurality of first resistors R1 are connected to the first selection unit U1, and second ends of the plurality of first resistors R1 are connected to the first adjustment circuit 12, wherein resistance values ​​of the plurality of first resistors are different;

[0100] The first selection unit U1 is configured to receive a first calibration signal and control a target first resistor R1 corresponding to the first calibration signal to be connected to the ground terminal and the first adjustment circuit 12 , respectively.

[0101] Specifically, when the low-level bit width time needs to be increased, the control module 30 controls the switching of a matching resistor with a larger resistance value, thereby increasing the voltage between pin 2 of the third resistor R3 of the first adjustment circuit 12 and GND; when the low-level bit width time needs to be reduced, the control module 30 controls the switching of a matching resistor with a smaller resistance value, thereby reducing the voltage between pin 2 of the third resistor R3 and GND.

[0102] Exemplarily, the seventh resistor R7, the eighth resistor R8, and the ninth resistor R9 serve as protection resistors. A first calibration signal is received via three pins (pins A, B, and C) of the first selection unit U1. Based on the first calibration signal, one of the pins X0 to X7 is selected to be connected to the X pin (pin 3) of the first selection unit U1, thereby activating the matching resistors on the corresponding pins, thereby achieving the purpose of switching the matching resistors.

[0103] Optionally, the control module 30 sends a first calibration signal in a binary code through three output terminals, and specifically can send 8 combinations, including 000, 001, 010, 011, 100, 101, 110, and 111. There can be 8 first resistors R1, namely R1-1, R1-2, R1-3, R1-4, R1-5, R1-6, R1-7, and R1-8. The resistance values ​​of each first resistor are different, and the multiple first resistors R1 can be sorted in order from small to large resistance. Each first resistor R1 corresponds to a binary code. The first selection unit U1 receives any one of the 8 combinations and controls the target first resistor corresponding to the binary code to be connected to the ground terminal and the first adjustment circuit 12 respectively.

[0104] For example, if the first calibration signal received by the first selection unit U1 is 010, the third first resistor is connected to the ground terminal and the first adjustment circuit 12 respectively.

[0105] In some optional embodiments, Figure 3 As shown, the isolation calibration control circuit 23 includes:

[0106] The optical coupling unit 23 a has a first end connected to the control module 30 , and a second end connected to the second calibration circuit 24 .

[0107] Specifically, the second calibration signal is isolated and outputted through the optical coupling unit 23 a , thereby performing adjustment on the isolated second adjustment circuit 22 .

[0108] For example, refer to Figure 3 , the optical coupling unit 23a is a plurality of optical coupling devices.

[0109] In some optional implementations, the second calibration circuit 24 is configured to receive a second calibration signal and control a second impedance corresponding to the second calibration signal to be connected to the second adjustment circuit 22 to perform bit width calibration on the second adjustment circuit.

[0110] Specifically, the second calibration circuit 24 receives the isolated second calibration signal and connects the second impedance corresponding to the second calibration signal to the second adjustment circuit, thereby adjusting the bit width of the waveform output by the second adjustment circuit.

[0111] In some optional implementations, the second calibration circuit 24 includes:

[0112] A second selection unit U2, the second selection unit U2 is connected to the isolation calibration control circuit 23;

[0113] a plurality of second resistors R2, wherein first ends of the plurality of second resistors R2 are connected to the second selection unit U2, and second ends of the plurality of second resistors R2 are connected to the second adjustment circuit 22, wherein the resistance values ​​of the plurality of second resistors are different;

[0114] The second selection unit U2 is configured to receive a second calibration signal and control the target second resistor R2 corresponding to the second calibration signal to be connected to the ground terminal and the second adjustment circuit 22 .

[0115] Specifically, when the low-level bit width time needs to be increased, the control module 30 controls the switching of a matching resistor with a larger resistance value, thereby increasing the voltage between pin 2 of the fourth resistor R4 of the second adjustment circuit 22 and GND; when the low-level bit width time needs to be reduced, the control module 30 controls the switching of a matching resistor with a smaller resistance value, thereby reducing the voltage between pin 2 of the fourth resistor R4 and GND.

[0116] Optionally, the control module 30 sends a second calibration signal in a binary code through three output terminals, and specifically can send 8 combinations, including 000, 001, 010, 011, 100, 101, 110, and 111. There can be 8 second resistors R2, namely R2-1, R2-2, R2-3, R2-4, R2-5, R2-6, R2-7, and R2-8. The resistance values ​​of the second resistors are different, and the multiple second resistors R2 can be sorted in order from small to large resistance. Each second resistor R2 corresponds to a binary code. The second selection unit U2 receives any one of the 8 combinations and controls the target second resistor corresponding to the binary code to be connected to the ground terminal and the second adjustment circuit 22 respectively.

[0117] Exemplarily, if the second calibration signal received by the second selection unit U2 is 010, the third second resistor is connected to the ground terminal and the second adjustment circuit 22 respectively.

[0118] For example, the fourteenth resistor R14, the fifteenth resistor R15, and the sixteenth resistor R16 serve as protection resistors. The second calibration signal is received via three pins (pins A, B, and C) of the second selection unit U2. Based on the second calibration signal, one of the pins X0 to X7 is selected to be connected to the X pin (pin 3) of the second selection unit U2, thereby activating the matching resistors on the corresponding pins, thereby achieving the purpose of switching the matching resistors.

[0119] The embodiment of the present application provides a method for controlling a smart meter, such as Figure 4 As shown, the method is described in detail in combination with the execution flow of the control method of the smart meter.

[0120] Step 1: upon receiving a calibration command from the first isolation calibration module, confirming first bit width deviation data of the calibration command from the first isolation calibration module, and detecting whether the first bit width deviation data is greater than a first preset bit width deviation threshold;

[0121] Step 2: If it is confirmed that the first bit width deviation data is greater than the first preset bit width deviation threshold, controlling the first isolation calibration module to perform calibration corresponding to the first bit width deviation data;

[0122] and / or;

[0123] Step 3: upon receiving a calibration command from the second isolation calibration module, outputting a test signal;

[0124] Step 4: Receive second bit width deviation data, and control the second isolation calibration module to perform calibration corresponding to the second bit width deviation data, wherein the second bit width deviation data is the second bit width deviation data output by the master station based on the test signal.

[0125] Specifically, refer to Figure 4 The first bit width deviation data is specifically the first low-level bit width deviation time. The control module 30 receives the calibration command of the first isolation calibration module, and detects the first low-level bit width deviation time between the first low-level bit width time of the calibration command of the first isolation calibration module and the first preset low-level bit width time. Then, if it is detected that the first low-level bit width deviation time is greater than the first preset bit width deviation threshold, the first calibration signal is output. If it is detected that the first low-level bit width deviation time is less than or equal to the first preset bit width deviation threshold, no calibration is required.

[0126] Specifically, the test signal is a test frame, and the second bit width deviation data is specifically a second low-level bit width deviation time. The master station receives the test frame and detects the second low-level bit width deviation time between the second low-level bit width time of the response frame and a second preset low-level bit width time. If the second low-level bit width deviation time is detected to be greater than a second preset bit width deviation threshold, the master station outputs calibration data. If the second low-level bit width deviation time is detected to be less than or equal to the second preset bit width deviation threshold, no calibration is required, and thus no calibration data is output.

[0127] In some optional implementations, the method for controlling the smart meter further includes:

[0128] Step (1): Detecting whether the received command is a calibration command of the first isolation calibration module;

[0129] Step (2): If the command is not a calibration command of the first isolation calibration module, detecting whether the command is a calibration command of the second isolation calibration module;

[0130] Step (3): If it is not the calibration command of the second isolation calibration module, it is confirmed to be the second bit width deviation data.

[0131] Specifically, refer to Figure 4 First, detect whether the data sent by the master station is the calibration command of the first isolated calibration module. If it is the calibration command of the first isolated calibration module, execute step one. If it is not the calibration command of the first isolated calibration module, continue to detect whether it is the calibration command of the second isolated calibration module, and execute step three. If it is not the calibration command of the second isolated calibration module, confirm it as the second bit width deviation data, and execute step four.

[0132] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus the necessary general hardware platform, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method.

Claims

1. A smart electric meter, characterized in that: The smart meter is connected to the main station, and the smart meter includes: a control module, a first isolation calibration module, a second isolation calibration module and a communication module; The communication module is connected to the master station; The first isolation calibration module is connected to the communication module and the control module respectively, and is used to isolate the first communication signal output by the master station and send it to the control module. The first isolation calibration module is also used to perform bit width calibration on the first communication signal; The second isolation calibration module is connected to the communication module and the control module respectively. The second isolation calibration module is used to isolate the second communication signal output by the control module and send it to the master station. The second isolation calibration module is also used to perform bit width calibration on the second communication signal.

2. The smart meter according to claim 1, wherein: The first isolation calibration module includes: a first isolated communication circuit, the first isolated communication circuit being connected to the master station and configured to isolate and output the first communication signal; a first adjustment circuit, the first adjustment circuit being connected to the first isolated communication circuit and the control module respectively, for receiving a first communication signal, performing waveform adjustment on the first communication signal, and then outputting the waveform to the control module; The control module is further configured to receive the first communication signal and output a first calibration signal when detecting that the first bit width deviation data of the first communication signal is greater than a first preset bit width deviation threshold; A first calibration circuit is connected to the first adjustment circuit and the control module respectively, and is used to receive the first calibration signal and perform bit width calibration on the first adjustment circuit.

3. The smart meter according to claim 1, wherein: The second isolation calibration module includes: a second isolated communication circuit, connected to the control module and configured to isolate and output the second communication signal; a second adjustment circuit, the second adjustment circuit being connected to the second isolated communication circuit and the master station respectively, for receiving a second communication signal, performing waveform adjustment on the second communication signal, and outputting the waveform to the master station; The master station receives the second communication signal and outputs calibration data when detecting that the second bit width deviation data of the second communication signal is greater than a second preset bit width deviation threshold; The control module is further configured to receive the calibration data and output a second calibration signal; an isolation calibration control circuit, connected to the control module, configured to receive the second calibration signal and output it in isolation; The second calibration circuit is connected to the second adjustment circuit and the isolation calibration control circuit respectively, and the second calibration circuit is used to isolate and receive the second calibration signal and perform bit width calibration on the second adjustment circuit.

4. The smart electric meter according to claim 2, characterized in that: The first calibration circuit is used to receive a first calibration signal and control a first impedance corresponding to the first calibration signal to be connected to the first adjustment circuit, so as to perform bit width calibration on the first adjustment circuit.

5. The smart meter according to claim 4, characterized in that: The first calibration circuit comprises: a first selection unit, the first selection unit being connected to the control module; a plurality of first resistors, wherein first ends of the plurality of first resistors are connected to the first selection unit, and second ends of the plurality of first resistors are connected to the first adjustment circuit, wherein resistance values ​​of the plurality of first resistors are different; The first selection unit is configured to receive a first calibration signal and control a target first resistor corresponding to the first calibration signal to be connected to a ground terminal and the first adjustment circuit respectively.

6. The smart electric meter according to claim 3, characterized in that: The isolation calibration control circuit includes: An optical coupling unit, wherein a first end of the optical coupling unit is connected to the control module, and a second end of the optical coupling unit is connected to the second calibration circuit.

7. The smart electric meter according to claim 3, characterized in that: The second calibration circuit is used to receive a second calibration signal and control a second impedance corresponding to the second calibration signal to be connected to the second adjustment circuit, so as to perform bit width calibration on the second adjustment circuit.

8. The smart electric meter according to claim 7, characterized in that: The second calibration circuit includes: a second selection unit connected to the isolation calibration control circuit; a plurality of second resistors, wherein first ends of the plurality of second resistors are connected to the second selection unit, and second ends of the plurality of second resistors are connected to the second adjustment circuit, wherein resistance values ​​of the plurality of second resistors are different; The second selection unit is configured to receive a second calibration signal and control a target second resistor corresponding to the second calibration signal to be connected to the ground terminal and the second adjustment circuit respectively.

9. A control method for a smart meter, characterized in that: The control method of the smart meter is applied to the smart meter according to any one of claims 1 to 8, and the control method of the smart meter includes: Upon receiving the calibration command from the first isolation calibration module, confirming the first bit width deviation data of the calibration command from the first isolation calibration module, and detecting whether the first bit width deviation data is greater than a first preset bit width deviation threshold; If it is confirmed that the first bit width deviation data is greater than the first preset bit width deviation threshold, controlling the first isolation calibration module to perform calibration corresponding to the first bit width deviation data; and / or; outputting a test signal upon receiving a calibration command from the second isolation calibration module; Second bit width deviation data is received, and a second isolation calibration module is controlled to perform calibration corresponding to the second bit width deviation data, wherein the second bit width deviation data is output by the master station based on the test signal.

10. The control method of the smart meter according to claim 9, characterized in that: The control method of the smart meter further includes: detecting whether the received command is a calibration command of the first isolation calibration module; If it is not a calibration command of the first isolated calibration module, detecting whether the command is a calibration command of the second isolated calibration module; If it is not the calibration command of the second isolation calibration module, it is determined to be the second bit width deviation data.

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