Straight-through direct-current electric energy metering device

Abstract

The utility model discloses a straight-through direct current electric energy metering device which comprises an MCU management unit, a voltage sampling circuit, a current sampling circuit, a temperature measurement circuit, a communication circuit, a hardware data encryption circuit, a clock circuit, an electric energy pulse output circuit and a switching power supply. The MCU management unit is electrically connected with the temperature measurement circuit, the communication circuit, the clock circuit and the pulse output circuit. The voltage sampling circuit is in electrical input connection with the MCU management unit through a wire. The current sampling circuit is in electrical input connection with the MCU management unit through a wire. The hardware data encryption circuit is in electrical input connection with the MCU management unit through a wire; the switching power supply is in linear input connection with the MCU management unit and comprises a first switch, a second switching power supply and a third switching power supply; the communication circuit comprises a Bluetooth communication circuit, an RS485 communication circuit and a CAN communication circuit. The utility model solves the technical problems that the existing direct-current device is poor in low-current metering precision, unstable and incapable of meeting various data transmission modes.

Description

Technical Field

[0001] The utility model relates to the technical field of electric energy metering, in particular to a direct-current electric energy metering device. Background Art

[0002] At present, the DC energy metering in the industry generally uses AC metering chips for DC metering, which has low sampling frequency, slow data transmission, and delay. The DC large current sampling is through an external DC shunt or Hall sensor. The DC energy meter and the current sampling device are separated and indirectly connected. There is no overall lead seal and they can be replaced at will on site, which has loopholes in the measurement regulations. At the same time, the energy measurement accuracy of the DC energy meter with large current direct access can only reach level 2 or level 1 in the full range, and the DC energy metering has poor measurement accuracy under low current conditions, that is, the current is ≤2%Ib, the measurement accuracy is unstable, the measurement data is transmitted without encryption, and the charging data is very easy to be tampered with. The patent document with application number 201710134261.6 discloses a high-precision wide-range vehicle-mounted DC electric energy meter, in which an active filter circuit, a demodulation circuit, a synchronization circuit, and an amplification and correction circuit are arranged inside the meter body; the current sampling module is filtered by the active filter circuit and demodulated by the demodulation circuit, and then enters the metering module after passing through the amplification and correction circuit, and the modulation and demodulation synchronization clock is provided by the synchronization circuit, which cannot solve the technical problems of poor small current measurement accuracy, instability, and inability to meet multiple data transmission modes of existing DC devices. Therefore, it is urgent to propose a direct-type DC electric energy metering device to solve the technical problems of poor small current measurement accuracy, instability, and inability to meet multiple data transmission modes of existing DC devices. Utility Model Content

[0003] The main purpose of the utility model is to provide a direct-current electric energy metering device, aiming to solve the technical problems of poor small current metering accuracy and instability of existing direct current devices and the inability to meet various data transmission modes.

[0004] To achieve the above-mentioned purpose, the utility model provides a direct-type direct current electric energy metering device, wherein the direct-type direct current electric energy metering device includes: an MCU management unit, a voltage sampling circuit, a current sampling circuit, a temperature measurement circuit, a communication circuit, a hardware data encryption circuit, a clock circuit, an electric energy pulse output circuit and a switching power supply; the MCU management unit is electrically connected to the temperature measurement circuit, the communication circuit, the clock circuit and the pulse output circuit respectively through wires; the voltage sampling circuit is electrically connected to the MCU management unit input through a wire; the current sampling circuit is electrically connected to the MCU management unit input through a wire; the hardware data encryption circuit is electrically connected to the MCU management unit input through a wire; the switching power supply is linearly connected to the MCU management unit, and the switching power supply includes a first switch, a second switching power supply and a third switching power supply; the communication circuit includes a Bluetooth communication circuit, an RS485 communication circuit and a CAN communication circuit.

[0005] In one of the preferred solutions, the voltage sampling circuit includes a resistor RVA, a voltage divider circuit, a resistor RT1, a first anti-aliasing circuit and a sampling chip U16; one end of the voltage divider circuit is respectively connected to the resistor RVA and an external device, and the other end of the voltage divider circuit is respectively connected to the resistor RT1, the first anti-aliasing circuit and the 5th pin of the sampling chip U16; the other end of the resistor RVA is respectively connected to the other end of the resistor RT1, the first anti-aliasing circuit, the 4th pin of the sampling chip U16 and the ground; the 13th and 14th pins of the sampling chip U16 are connected to the MCU management unit; the 16th pin of the sampling chip U16 is respectively connected to the resistor RL1 and the capacitor CJ2, the other end of the resistor RL1 is connected to the switching power supply, and the other end of the capacitor CJ2 is grounded; wherein the 5th pin of the sampling chip U16 is the IAP pin, the 4th pin of the sampling chip U16 is the IAN pin, the 13th pin of the sampling chip U16 is the RX pin, the 14th pin of the sampling chip U16 is the TX pin, and the 16th pin of the sampling chip U16 is the VDD pin.

[0006] One of the preferred solutions, the current sampling circuit includes a DC shunt RB0, a second anti-aliasing circuit and a sampling chip U15; one end of the DC shunt RB0 is respectively connected to the positive end of the external device and the second anti-aliasing circuit, and the other end of the DC shunt RB0 is respectively connected to the negative end of the external device and the second anti-aliasing circuit; the second anti-aliasing circuit is respectively connected to pins 4 and 5 of the sampling chip U15; pins 13 and 14 of the sampling chip U15 are connected to the MCU management unit; pin 16 of the sampling chip U15 is respectively connected to a resistor RL2 and a capacitor CJ1, the other end of the resistor RL2 is connected to a switching power supply, and the other end of the capacitor CJ1 is grounded; wherein pin 4 of the sampling chip U15 is an IAN pin, pin 5 of the sampling chip U15 is an IAP pin, pin 13 of the sampling chip U15 is an RX pin, pin 14 of the sampling chip U15 is a TX pin, and pin 16 of the sampling chip U15 is a VDD pin.

[0007] One of the preferred schemes, the temperature measurement circuit includes a temperature sensor UT1, a resistor R76 and a single-chip microcomputer U88; the DQ end of the temperature sensor UT1 is respectively connected to the resistor R76 and the GPIO port of the single-chip microcomputer U88, and the GND end of the temperature sensor UT1 and the GND end of the single-chip microcomputer U88 are grounded; the VDD end of the single-chip microcomputer U88 and the other end of the resistor R76 are connected to the switching power supply.

[0008] In one of the preferred solutions, the Bluetooth communication circuit is electrically connected to the MCU management unit through a wire; the Bluetooth communication circuit includes a Bluetooth module U1;

[0009] Pin 5 of the Bluetooth module U1 is connected to the resistor RL1 and the capacitor CL10 respectively, and the other end of the resistor RL1 is connected to the diode D15 and the resistor RL4 respectively;

[0010] Pin 6 of the Bluetooth module U1 is connected to the resistor RL2 and the capacitor CL11 respectively, and the other end of the resistor RL2 is connected to the diode D17 and the resistor RL5 respectively;

[0011] Pin 7 of the Bluetooth module U1 is connected to the resistor RL3 and the capacitor CL12 respectively, and the other end of the resistor RL3 is connected to the diode D18 and the resistor RL6 respectively; the other ends of the capacitors CL10, CL11 and CL12 are grounded, and the other ends of the resistors RL4, RL5 and RL6 are connected to pin 1 of the socket JP7;

[0012] Pins 18 and 19 of the Bluetooth module U1 are connected to the MCU management unit;

[0013] Pin 23 of the Bluetooth module U1 is connected to a resistor R97 and a capacitor C93, the other end of the capacitor C93 is grounded, and the other end of the resistor R97 is connected to pin 4 of the socket JP7;

[0014] The 24th and 25th pins of the Bluetooth module U1 are connected to the 2nd and 3rd pins of the socket JP7 respectively;

[0015] Among them, pin 5 of the Bluetooth module U1 is the P0.03 / AIN1(L) pin, pin 6 of the Bluetooth module U1 is the P0.02 / AIN0 pin, pin 7 of the Bluetooth module U1 is the P0.04 / AIN2 pin, pin 18 of the Bluetooth module U1 is the P0.07 pin, pin 19 of the Bluetooth module U1 is the P0.14 pin, pin 23 of the Bluetooth module U1 is the P0.18 / nRESET pin, pin 24 of the Bluetooth module U1 is the SWCLK pin, and pin 25 of the Bluetooth module U1 is the SWDIO pin.

[0016] In one preferred solution, the RS485 communication circuit is electrically connected to the MCU management unit output through a wire; the RS485 communication circuit includes a communication chip U10;

[0017] Pins 1 and 4 of the communication chip U10 are connected to the communication isolation circuit;

[0018] Pins 2 and 3 of the communication chip U10 are connected to pins 2 and 3 of the optocoupler N7 respectively;

[0019] Pin 5 of the communication chip U10 is connected to the resistor R96 and the ground respectively, the other end of the resistor R96 is connected to pin 7 of the communication chip U10, the resistor RT30, the transient protector V10 and the transient protector V5 respectively, the other end of the resistor RT30 is connected to the MCU management unit, the other end of the transient protector V5 is connected to pin 6 of the communication chip U10, and the other end of the transient protector V10 is grounded;

[0020] The 6 pins of the communication chip U10 are respectively connected to the resistor R95, the resistor RT79 and the transient protector V11; the other end of the resistor R95 is connected to the switching power supply, the other end of the resistor RT79 is connected to the MCU management unit, and the other end of the transient protector V11 is grounded;

[0021] The 8 pins of the communication chip U10 are connected to the capacitor C87 and the switch power supply respectively, and the other end of the capacitor C87 is grounded;

[0022] Among them, pin 1 of the communication chip U10 is the R pin, pin 2 of the communication chip U10 is the RE pin, pin 3 of the communication chip U10 is the DE pin, pin 4 of the communication chip U10 is the D pin, pin 5 of the communication chip U10 is the GND pin, pin 6 of the communication chip U10 is the A pin, pin 7 of the communication chip U10 is the B pin, and pin 8 of the communication chip U10 is the VCC pin.

[0023] In one preferred solution, the CAN communication circuit is electrically connected to the MCU management unit output through a wire; the CAN communication circuit includes a communication chip U89;

[0024] Pins 1 and 4 of the communication chip U89 are connected to the communication isolation circuit;

[0025] Pin 3 of the communication chip U89 is connected to the power supply terminal and the capacitor CP41 respectively, and pins 2 and 8 of the communication chip U89 and the other end of the capacitor CP41 are grounded;

[0026] The 6 pins of the communication chip U89 are respectively connected to the resistor R19, the transient protector V6, the transient protector V13 and the resistor RT1, the other end of the transient protector V13 is respectively connected to the transient protector V12 and the ground, and the other end of the resistor RT1 is connected to the MCU management unit;

[0027] Pin 7 of the communication chip U89 is respectively connected to the resistor R19, the transient protector V6, the other end of the transient protector V12 and the resistor RT2; the other end of the resistor RT2 is connected to the MCU management unit;

[0028] Among them, pin 1 of the communication chip U89 is the TXD pin, pin 2 of the communication chip U89 is the VSS pin, pin 3 of the communication chip U89 is the VCC pin, pin 4 of the communication chip U89 is the RXD pin, pin 6 of the communication chip U89 is the CANL pin, pin 7 of the communication chip U89 is the CANH pin, and pin 8 of the communication chip U89 is the Rs pin.

[0029] One of the preferred schemes, the hardware data encryption circuit includes an encryption chip U17; pin 2 of the encryption chip U17 is respectively connected to pin 7 and the MCU management unit; pin 3 of the encryption chip U17 is respectively connected to pin 6 and the MCU management unit; pins 4 and 5 of the encryption chip U17 are both connected to the MCU management unit; pin 8 of the encryption chip U17 is respectively connected to capacitor C97 and the collector of transistor QD4, the emitter of the transistor QD4 is connected to the power supply end, and the base of the transistor QD4 is connected to the MCU management unit through a resistor R101; wherein, pin 2 of the encryption chip U17 is a MOSI pin, pin 3 of the encryption chip U17 is a MISO pin, pin 4 of the encryption chip U17 is an SSN pin, pin 5 of the encryption chip U17 is an SCK pin, pin 6 of the encryption chip U17 is a MISO pin, pin 7 of the encryption chip U17 is a MOSI pin, and pin 8 of the encryption chip U17 is a VCC pin.

[0030] One of the preferred schemes, the clock circuit includes a clock chip U84; Pin 2 of the clock chip U84 is respectively connected to the MCU management unit and the resistor R49, the other end of the resistor R49 is respectively connected to the resistor R50, the switching power supply and the pins 1 and 2 of the dual diode D1; Pin 6 of the clock chip U84 is respectively connected to the capacitor C52, the pin 3 of the dual diode D1 and the pin 3 of the dual diode D2, the other end of the capacitor C52 is grounded, Pins 1 and 2 of the dual diode D2 are connected to the battery BT1, the other end of the battery BT1 is connected to the resistor R26, the other end of the resistor R26 is connected to the switch S1, and the other end of the switch S1 is grounded; wherein Pin 2 of the clock chip U84 is the SCL pin, and Pin 6 of the clock chip U84 is the VDD pin.

[0031] One of the preferred schemes, the electric energy pulse output circuit includes an optocoupler N11; pin 1 of the optocoupler N11 is connected to a resistor R70, and the other end of the resistor R70 is connected to a switching power supply; pin 2 of the optocoupler N11 is respectively connected to a capacitor CG1 and an external receiving end, pins 3 and 4 of the optocoupler N11 are connected to an MCU management unit, and the other end of the capacitor CG1 is grounded; pin 1 of the optocoupler N11 is an LED anode, pin 2 of the optocoupler N11 is an LED cathode, pin 3 of the optocoupler N11 is an emitter of a photodetector, and pin 4 of the optocoupler N11 is a collector of the photodetector.

[0032] In the above technical scheme of the utility model, the direct-type DC electric energy metering device includes: an MCU management unit, a voltage sampling circuit, a current sampling circuit, a temperature measurement circuit, a communication circuit, a hardware data encryption circuit, a clock circuit, an electric energy pulse output circuit and a switching power supply; the MCU management unit is electrically connected to the temperature measurement circuit, the communication circuit, the clock circuit and the pulse output circuit respectively through wires; the voltage sampling circuit is electrically connected to the MCU management unit input through wires; the current sampling circuit is electrically connected to the MCU management unit input through wires; the hardware data encryption circuit is electrically connected to the MCU management unit input through wires; the switching power supply is linearly connected to the MCU management unit input, and the switching power supply includes a first switch, a second switching power supply and a third switching power supply; the communication circuit includes a Bluetooth communication circuit, an RS485 communication circuit and a CAN communication circuit. The utility model has a simple structure and is easy to use, and solves the technical problems of poor precision and instability of small current measurement of existing DC devices and the inability to meet multiple data transmission modes.

[0033] In the utility model, a small DC signal is measured by a metering chip with extremely low DC bias, through an independent, high-speed, high-precision voltage sampling circuit and a current sampling circuit that are electrically connected to the MCU management unit with wires, thereby avoiding the problem of mutual interference between channels during AD sampling, ensuring that the 0.5-level metering accuracy is more stable and reliable, and the maximum current directly connected can reach 400A and the voltage is 1000V, solving the problems of poor small current accuracy and instability of conventional instruments.

[0034] In the present invention, a high-precision temperature measurement circuit is provided instead of the traditional thermistor temperature measurement, so the temperature measurement accuracy is higher, the temperature measurement range is -50°C-150°C, and the error is within the range of ±0.5°C.

[0035] In the utility model, the communication circuit includes a Bluetooth communication circuit, an RS485 communication circuit and a CAN communication circuit, and has various data transmission modes, including RS485, Bluetooth and CAN bus communication modes, which can meet various DC detection and measurement needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0037] Figure 1 This is a schematic diagram of a direct-flow DC electric energy metering device according to an embodiment of the utility model;

[0038] Figure 2 This is a schematic diagram of a voltage sampling circuit according to an embodiment of the utility model;

[0039] Figure 3 A schematic diagram of a current sampling circuit according to an embodiment of the present utility model;

[0040] Figure 4 This is a schematic diagram of a temperature measurement circuit according to an embodiment of the present utility model;

[0041] Figure 5 This is a schematic diagram of a Bluetooth communication circuit according to an embodiment of the present utility model;

[0042] Figure 6 This is a schematic diagram of a communication isolation circuit according to an embodiment of the present utility model;

[0043] Figure 7 Schematic diagram of RS485 communication circuit of the utility model embodiment;

[0044] Figure 8 This is a schematic diagram of a CAN communication circuit according to an embodiment of the utility model;

[0045] Fig. 9 This is a schematic diagram of a hardware data encryption circuit according to an embodiment of the present utility model;

[0046] Fig.10 A schematic diagram showing a circuit diagram of an embodiment of the utility model;

[0047] Fig.11 This is a schematic diagram of a data storage circuit according to an embodiment of the utility model;

[0048] Fig.12 It is a schematic diagram of an electric energy pulse output circuit and an optical pulse output circuit of an embodiment of the utility model;

[0049] Fig.13 This is a schematic diagram of a clock circuit according to an embodiment of the utility model;

[0050] Fig.14 This is a schematic diagram of a first switching power supply according to an embodiment of the utility model;

[0051] Fig.15 This is a schematic diagram of a second switching power supply according to an embodiment of the utility model;

[0052] Fig.16 This is a schematic diagram of a third switching power supply according to an embodiment of the present utility model.

[0053] Description of Figure Numbers:

[0054] 1. MCU management unit; 2. Voltage sampling circuit; 3. Current sampling circuit; 4. Temperature measurement circuit; 5. Clock circuit; 6. Electric energy pulse output circuit; 7. Display circuit; 8. Hardware data encryption circuit; 9. Data storage circuit; 10. Optical pulse output circuit; 11. Communication circuit; 12. Switching power supply.

[0055] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with the implementation methods and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0057] It should be noted that all directional indications (such as up, down, etc.) in the implementation mode of the utility model are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0058] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0059] Furthermore, the technical solutions between the various implementation modes of the present invention may be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0060] See also Figure 1According to one aspect of the utility model, the utility model provides a direct-type DC electric energy metering device, wherein the direct-type DC electric energy metering device includes: an MCU management unit 1, a voltage sampling circuit 2, a current sampling circuit 3, a temperature measurement circuit 4, a communication circuit 11, a hardware data encryption circuit 8, a clock circuit 5, an electric energy pulse output circuit 6 and a switching power supply 12; the MCU management unit 1 is electrically connected to the temperature measurement circuit 4, the communication circuit 11, the clock circuit 5 and the pulse output circuit through wires respectively; the voltage sampling circuit 2 is electrically connected to the MCU management unit 1 through a wire; the current sampling circuit 3 is electrically connected to the MCU management unit 1 through a wire; the hardware data encryption circuit 8 is electrically connected to the MCU management unit 1 through a wire; the communication circuit 11 includes a Bluetooth communication circuit 11, an RS485 communication circuit and a CAN communication circuit 11; the switching power supply 12 is linearly connected to the MCU management unit 1, and the switching power supply 12 includes a first switch, a second switching power supply and a third switching power supply.

[0061] Specifically, in this embodiment, the MCU management unit 1 adopts a V8510P single-chip microcomputer. The V8510P is a highly integrated 32-bit MCU series product suitable for multi-functional, low-power IoT applications. It integrates a Cortex-M0 core, 512KBFLASH, 64KB SRAM, UART / SPI / I2C interface, LCD, WDT and RTC; the current data collected by the high-precision, high-speed voltage sampling circuit 2 and the current sampling circuit 3 is transmitted to the single-chip microcomputer in a high-speed serial port mode, and DC measurement is performed.

[0062] Specifically, in this embodiment, see Figure 2The voltage sampling circuit 2 includes a resistor RVA, a voltage divider circuit, a resistor RT1, a first anti-aliasing circuit and a sampling chip U16; one end of the voltage divider circuit is connected to the resistor RVA and an external device respectively, and the other end of the voltage divider circuit is connected to the resistor RT1, the first anti-aliasing circuit and the 5th pin of the sampling chip U16 respectively; the other end of the resistor RVA is connected to the other end of the resistor RT1, the first anti-aliasing circuit, the 4th pin of the sampling chip U16 and the ground terminal respectively; the 13th and 14th pins of the sampling chip U16 are connected to the MCU management unit 1 is connected; the 16 pins of the sampling chip U16 are respectively connected to the resistor RL1 and the capacitor CJ2, the other end of the resistor RL1 is connected to the switching power supply 12, and the other end of the capacitor CJ2 is grounded; the 1, 2, and 3 pins of the sampling chip U16 are grounded; the 6 pins of the sampling chip U16 are respectively connected to the capacitor CJ17 and the capacitor CJ14, and the other ends of the capacitors CJ17 and CJ14 are grounded; the 9, 10, and 12 pins of the sampling chip U16 are respectively connected to the capacitors CJ3, Resistors RJ2 and RJ7 are grounded; Pin 11 of the sampling chip U16 is connected to the power supply terminal through resistor RJ8; Pin 15 of the sampling chip U16 is grounded; A voltage divider circuit is set at the front end of the voltage sampling circuit 2 to ensure the sampling accuracy within the full temperature range, and the signal aliasing is eliminated through the first anti-aliasing circuit and transmitted to the sampling chip U16. The sampling chip U16 adopts Wan Gao V9260S, with a dynamic range of 8000:1, a minimum resolution of up to 6uV, and an extremely low DC bias voltage, and a sampling frequency of up to 819.2 KHz, the extremely high sampling frequency ensures the measurement accuracy of 0.5 level in the range of low temperature -25℃ to high temperature 70℃, and the collected voltage data is transmitted to the MCU management unit 1 through the serial port for storage and measurement; wherein, the 5th pin of the sampling chip U16 is the IAP pin, the 4th pin of the sampling chip U16 is the IAN pin, the 13th pin of the sampling chip U16 is the RX pin, the 14th pin of the sampling chip U16 is the TX pin, and the 16th pin of the sampling chip U16 is the VDD pin.

[0063] Specifically, in the present embodiment, the voltage divider circuit includes resistors RA1, RA2, RA3, RA4, RA5, RA6, RA7, RA8, RA9 and RA10; one end of the resistor R10 is connected to an external device and a resistor RVA respectively, the other end of the resistor RA10 is connected to resistors RA9, RA8, R7, RA6, RA1, RA2, RA3, RA4 and RA5 in sequence, and the other end of the resistor RA5 is connected to resistor RT1 and a first anti-aliasing circuit respectively; by providing a high-precision resistor voltage divider circuit at the front end of the DC voltage of the voltage sampling circuit 2, the resistor RT1 is a high-precision sampling resistor, and all resistors adopt high-reliability temperature drift of 25ppm and accuracy level of 0.2%, thereby ensuring sampling accuracy within the full temperature range.

[0064] Specifically, in the present embodiment, the first anti-aliasing circuit includes a resistor R13, a capacitor C45, a capacitor C55 and a capacitor C31; one end of the resistor R45 is respectively connected to the resistor RT1, the capacitor C31 and the 5-pin of the sampling chip U16; the other end of the resistor R45 is respectively connected to the capacitor C55 and the ground, the other end of the capacitor C55 is respectively connected to the resistor R13, the other end of the capacitor C31 and the 4-pin of the sampling chip U16, and the other end of the resistor R13 is respectively connected to the sampling resistor RT1, the resistor RVA and the ground; the first anti-aliasing circuit eliminates signal aliasing, restores the original signal, and avoids signal distortion.

[0065] Specifically, in this embodiment, see Figure 3The current sampling circuit 3 includes a DC shunt RB0, a second anti-aliasing circuit and a sampling chip U15; one end of the DC shunt RB0 is respectively connected to the positive end of the external device and the second anti-aliasing circuit, and the other end of the DC shunt RB0 is respectively connected to the negative end of the external device and the second anti-aliasing circuit; the second anti-aliasing circuit is respectively connected to pins 4 and 5 of the sampling chip U15; pins 13 and 14 of the sampling chip U15 are connected to the MCU management unit 1; pin 16 of the sampling chip U15 is respectively connected to the resistor RL2 and the capacitor CJ1 The other end of the resistor RL2 is connected to the switching power supply 12, and the other end of the capacitor CJ1 is grounded; the 1, 2, and 3 pins of the sampling chip U15 are grounded; the 6 pins of the sampling chip U15 are connected to the capacitor CJ12 and the capacitor CJ13 respectively, and the other ends of the capacitors CJ12 and CJ13 are grounded; the 9, 10, 11, and 12 pins of the sampling chip U15 are grounded through the capacitor CJ11, the resistor R90, the resistor R87, and the resistor R86 respectively; the 15 pin of the sampling chip U15 is grounded; the DC shunt RB0 is High-precision DC manganese copper shunt, resistance value is 23.5±1uΩ, except for manganese copper, the copper part is tinned, the shunt is directly welded on the circuit board through the sampling pin, shortening the sampling signal distance and reducing signal interference; the sampling chip U15 adopts Wan Gao V9260S, with a dynamic range of 8000:1, a minimum resolution of 6uV, and a DC bias voltage handover, and a sampling frequency of up to 819.2KHz. The extremely high sampling frequency can ensure a measurement accuracy of 0.5 in the range of low temperature -25℃ to high temperature 70℃, and the collected current data It is transmitted to the MCU management unit 1 through the serial port for storage and measurement. The utility model measures direct current by respectively adopting a voltage sampling circuit 2 and a current sampling circuit 3 in cooperation with the MCU management unit 1, thereby avoiding the problem of mutual interference between channels during AD sampling. Among them, pin 4 of the sampling chip U15 is the IAN pin, pin 5 of the sampling chip U15 is the IAP pin, pin 13 of the sampling chip U15 is the RX pin, pin 14 of the sampling chip U15 is the TX pin, and pin 16 of the sampling chip U15 is the VDD pin.

[0066] Specifically, in this embodiment, the second anti-aliasing circuit includes a resistor RB2, a resistor RB3, a capacitor CB1, a capacitor CB2 and a capacitor CB5; one end of the resistor RB2 is connected to the resistor RB0, the other end of the resistor RB2 is respectively connected to the capacitor CB1, the capacitor CB5 and the 5th pin of the sampling chip U15, the other end of the capacitor CB1 is respectively connected to the capacitor CB2 and the ground, and the other end of the capacitor CB2 is respectively connected to the capacitor CB5, the resistor RB3 and the 4th pin of the sampling chip U15; the signal aliasing is eliminated by the second anti-aliasing circuit, the original signal is restored, and signal distortion is avoided.

[0067] Specifically, in this embodiment, see Figure 4 The temperature measurement circuit 4 includes a temperature sensor UT1, a resistor R76 and a single-chip microcomputer U88; the DQ end of the temperature sensor UT1 is connected to the resistor R76 and the GPIO port of the single-chip microcomputer U88 respectively, and the GND end of the temperature sensor UT1 and the GND end of the single-chip microcomputer U88 are grounded; the VDD end of the single-chip microcomputer U88 and the other end of the resistor R76 are connected to the switching power supply 12; the temperature sensor UT1 is a high-precision dual-pin digital pulse output temperature sensor NST1001, with a temperature measurement range of -50°C to 150°C, without the need for system calibration or hardware or software compensation Under this condition, high-precision temperature detection within the entire temperature range can be achieved. Different from the traditional temperature measurement using thermistors, the temperature measurement accuracy of the utility model is higher, and the error is only within the range of ±0.5°C; the temperature sensor UT1 adopts a parasitic power supply mode, that is, it uses the high-level time of the communication pin DQ to charge and complete the work, using a two-pin connection method, the DQ end serves as the communication digital pulse high output end and the parasitic power supply end, the GND end is grounded, the GPIO port of the microcontroller U88 is connected to the DQ end of the temperature sensor UT1, the pulses output after each temperature conversion are counted, and then the number of pulses is converted into temperature.

[0068] Specifically, in this embodiment, see Figure 5, the Bluetooth communication circuit 11 is electrically connected to the MCU management unit 1 through a wire; the Bluetooth communication circuit 11 includes a Bluetooth module U1; the 5 pins of the Bluetooth module U1 are respectively connected to the resistor RL1 and the capacitor CL10, and the other end of the resistor RL1 is respectively connected to the diode D15 and the resistor RL4; the 6 pins of the Bluetooth module U1 are respectively connected to the resistor RL2 and the capacitor CL11, and the other end of the resistor RL2 is respectively connected to the diode D17 and the resistor RL5; the 7 pins of the Bluetooth module U1 are respectively connected to the resistor RL3 and the capacitor CL12, and the other end of the resistor RL3 is respectively connected to the diode D18 is connected to resistor RL6; the other ends of the capacitors CL10, CL11 and CL12 are grounded, and the other ends of the resistors RL4, RL5 and RL6 are connected to pin 1 of socket JP7; pins 18 and 19 of the Bluetooth module U1 are connected to MCU management unit 1; pin 23 of the Bluetooth module U1 is connected to resistor R97 and capacitor C93, the other end of the capacitor C93 is grounded, and the other end of the resistor R97 is connected to pin 4 of socket JP7; pins 24 and 25 of the Bluetooth module U1 are connected to pins 2 and 3 of socket JP7 respectively; wherein, the Bluetooth module U1 The 5th pin of the Bluetooth module U1 is the P0.03 / AIN1(L) pin, the 6th pin of the Bluetooth module U1 is the P0.02 / AIN0 pin, the 7th pin of the Bluetooth module U1 is the P0.04 / AIN2 pin, the 18th pin of the Bluetooth module U1 is the P0.07 pin, the 19th pin of the Bluetooth module U1 is the P0.14 pin, the 23rd pin of the Bluetooth module U1 is the P0.18 / nRESET pin, the 24th pin of the Bluetooth module U1 is the SWCLK pin, and the 25th pin of the Bluetooth module U1 is the SWDIO pin; the Bluetooth module U1 adopts the low-power Bluetooth module model BB820. The present invention does not make any specific limitation on the dental module and can be set according to specific needs; the Bluetooth module U1 is a small-sized, low-power Bluetooth 5.1 wireless module with a stamp-type package interface, which supports master-slave synchronization, that is, it realizes the roles of BLE host and slave at the same time, and the maximum Bluetooth connection link supports 20 channels. The 5, 6, and 7 pins of the Bluetooth module U1 are connected to the MCU management unit 1, and the MCU management unit 1 sends clock pulses and power pulses to the Bluetooth module U1. Through Bluetooth wireless forwarding, it can realize both the ordinary Bluetooth wireless communication function and the wireless calibration function of the clock daily timing error and the power error.

[0069] Specifically, in this embodiment, see Figure 7, the RS485 communication circuit is electrically connected to the MCU management unit 1 through a wire; the RS485 communication circuit includes a communication chip U10; the 1 and 4 pins of the communication chip U10 are connected to the communication isolation circuit; the 2 and 3 pins of the communication chip U10 are respectively connected to the 2 and 3 pins of the optocoupler N7; the 5 pins of the communication chip U10 are respectively connected to the resistor R96 and the ground terminal, the other end of the resistor R96 is respectively connected to the 7 pins of the communication chip U10, the resistor RT30, the transient protector V10 and the transient protector V5, the other end of the resistor RT30 is connected to the MCU management unit 1, the other end of the transient protector V5 is connected to the 6 pins of the communication chip U10, and the other end of the transient protector V10 is grounded; the 6 pins of the communication chip U10 are respectively connected to the resistor R95, the resistor RT79 and the transient protector V11; the other end of the resistor R95 is connected to the switching power supply 12, and the other end of the resistor RT79 is connected to the M CU management unit 1 is connected, and the other end of the transient protector V11 is grounded; 8 pins of the communication chip U10 are respectively connected to capacitor C87 and switching power supply 12, and the other end of the capacitor C87 is grounded; wherein, pin 1 of the communication chip U10 is an R pin, pin 2 of the communication chip U10 is an RE pin, pin 3 of the communication chip U10 is a DE pin, pin 4 of the communication chip U10 is a D pin, pin 5 of the communication chip U10 is a GND pin, pin 6 of the communication chip U10 is an A pin, pin 7 of the communication chip U10 is a B pin, and pin 8 of the communication chip U10 is a VCC pin; the resistor RT30 and the resistor RT79 are thermistors, and the transient protector V10, the transient protector V11 and the transient protector V5 are provided to protect the RS485 communication interface from 1000V surge impact, AC 380V withstand voltage and 4KV electrostatic protection cable, thereby improving the electromagnetic compatibility performance of the circuit.

[0070] Specifically, in this embodiment, see Figure 8, the CAN communication circuit 11 is electrically connected to the MCU management unit 1 through a wire; the CAN communication circuit 11 includes a communication chip U89; the 1 and 4 pins of the communication chip U89 are connected to the communication isolation circuit; the 3 pins of the communication chip U89 are respectively connected to the power supply end and the capacitor CP41, and the 2 and 8 pins of the communication chip U89 and the other end of the capacitor CP41 are grounded; the 6 pins of the communication chip U89 are respectively connected to the resistor R19, the transient protector V6, the transient protector V13 and the resistor RT1, the other end of the transient protector V13 is respectively connected to the transient protector V12 and the ground end, and the other end of the resistor RT1 is connected to the MCU management unit 1; the 7 pins of the communication chip U89 are respectively connected to the resistor R19, the transient protector V6, the other end of the transient protector V12 and the resistor RT2 ; The other end of the resistor RT2 is connected to the MCU management unit 1; wherein, pin 1 of the communication chip U89 is the TXD pin, pin 2 of the communication chip U89 is the VSS pin, pin 3 of the communication chip U89 is the VCC pin, pin 4 of the communication chip U89 is the RXD pin, pin 6 of the communication chip U89 is the CANL pin, pin 7 of the communication chip U89 is the CANH pin, and pin 8 of the communication chip U89 is the Rs pin; in the utility model, the communication chip U89 adopts a communication chip with model TPT1255, which is not specifically limited in the utility model and can be set according to needs; the communication chip U89 meets the ISO11898 standard, can reach 5Mbps high-speed communication, has high anti-static performance, and can withstand a human body electrostatic discharge mode of up to ±15KV.

[0071] Specifically, in this embodiment, see Figure 6The communication isolation circuit includes a capacitor U50; a pin 1 of the capacitor U50 is connected to a resistor R114 and a capacitor C109, the other end of the resistor R114 is connected to a power supply terminal and a capacitor CP10, and the other end of the capacitor CP10 is connected to the other end of the capacitor C109, a pin 2 of the capacitor U50 and a ground terminal; pins 12 and 14 of the capacitor U50 are connected to a CAN communication circuit 11, pins 4, 6, 11 and 13 of the capacitor U50 are connected to an RS485 communication circuit, and pins 15 of the capacitor U50 are connected to a power supply terminal and a capacitor CP10, respectively. Capacitor C103 is connected to the ground, and pin 16 of the isolator U50 is respectively connected to the other end of capacitor C103 and resistor R115, the other end of the resistor R115 is respectively connected to the switching power supply 12 and capacitor CP58, and the other end of the capacitor CP58 is grounded; the isolator U50 adopts a high-speed isolator device with model NSi8242C1-DSWR, with a maximum isolation voltage of 5000Vrms, a communication baud rate of up to 100Mbps, and a four-channel two-input and two-output port, which can meet the needs of high-speed CAN communication and high-speed RS485 communication at the same time.

[0072] Specifically, in this embodiment, see Fig. 9 , the hardware data encryption circuit 8 includes an encryption chip U17; pin 2 of the encryption chip U17 is respectively connected to pin 7 and the MCU management unit 1; pin 3 of the encryption chip U17 is respectively connected to pin 6 and the MCU management unit 1; pins 4 and 5 of the encryption chip U17 are both connected to the MCU management unit 1; pin 8 of the encryption chip U17 is respectively connected to capacitor C97 and the collector of transistor QD4, the emitter of the transistor QD4 is connected to the power supply terminal, and the base of the transistor QD4 is connected to the MCU management unit 1 through a resistor R101; wherein pin 2 of the encryption chip U17 is a MOSI pin, and pin 3 of the encryption chip U17 is a MISO pin, Pin 4 of the encryption chip U17 is the SSN pin, pin 5 of the encryption chip U17 is the SCK pin, pin 6 of the encryption chip U17 is the MISO pin, pin 7 of the encryption chip U17 is the MOSI pin, and pin 8 of the encryption chip U17 is the VCC pin; the encryption chip adopts a security module of model HGW698SZ, and a variety of security protection mechanisms can be implemented through the hardware data encryption circuit 8 to effectively ensure the confidentiality and integrity of data transmission; the MCU management unit 1 controls the power supply of the encryption chip U17 by controlling the transistor QD4 to ensure data security; the utility model ensures data security and independence through the hardware data encryption circuit 8.

[0073] Specifically, in this embodiment, see Fig.13, the clock circuit 5 includes a clock chip U84; the 2 pins of the clock chip U84 are respectively connected to the MCU management unit 1 and the resistor R49, and the other end of the resistor R49 is respectively connected to the resistor R50, the switching power supply 12 and the 1 and 2 pins of the dual diode D1; the 6 pins of the clock chip U84 are respectively connected to the capacitor C52, the 3 pins of the dual diode D1 and the 3 pins of the dual diode D2, the other end of the capacitor C52 is grounded, the 1 and 2 pins of the dual diode D2 are connected to the battery BT1, the other end of the battery BT1 is connected to the resistor R26, the other end of the resistor R26 is connected to the switch S1, and the other end of the switch S1 is grounded; wherein, the clock chip U Pin 2 of 84 is the SCL pin, and pin 6 of the clock chip U84 is the VDD pin; the clock chip U84 adopts the RX-8025T model high-precision clock chip with temperature compensation, supports the range of -40℃-85℃, and the clock error output meets 0.5s / d, which can reliably ensure the time accuracy of metering and billing, and supports the time synchronization function; the clock circuit 5 has a dual power supply switching function, with a clock battery and an external switching power supply 12 for power supply switching. When the system is powered on and working normally, the switching power supply 12 provides the clock power supply. In the low-power consumption case of system power outage or no power, the clock chip U84 power supply automatically switches to power supplied by a large-capacity battery, which can achieve seamless power switching to ensure clock accuracy.

[0074] Specifically, in this embodiment, see Fig.12 The electric energy pulse output circuit 6 includes an optical coupler N11; pin 1 of the optical coupler N11 is connected to a resistor R70, and the other end of the resistor R70 is connected to a switching power supply 12; pin 2 of the optical coupler N11 is respectively connected to a capacitor CG1 and an external receiving end, pins 3 and 4 of the optical coupler N11 are connected to an MCU management unit 1, and the other end of the capacitor CG1 is grounded; pin 1 of the optical coupler N11 is an LED anode, pin 2 of the optical coupler N11 is an LED cathode, pin 3 of the optical coupler N11 is an emitter of a photodetector, and pin 4 of the optical coupler N11 is a collector of a photodetector; the electric energy pulse output is electrically isolated by the optical coupler N11, and the isolation voltage can reach an AC withstand voltage of 4KV.

[0075] Specifically, in this embodiment, the direct-type DC electric energy metering device also includes an optical pulse output circuit 10, which is electrically connected to the MCU management unit 1; the optical pulse output circuit 10 includes an indicator light LP2, a resistor R31 and a capacitor C24; one end of the indicator light LP2 is connected to the MCU management unit 1, and the other end of the indicator light LP2 is connected to the resistor R31, and the other end of the resistor R31 is respectively connected to the external receiving end and the capacitor C24, and the other end of the capacitor C24 is grounded; the MCU management unit 1 controls the on and off of the LED light LP2 by outputting electric energy pulses, thereby realizing the functions of metering indication and electric energy optical pulse verification.

[0076] Specifically, in this embodiment, see Fig.10 The direct-type DC electric energy metering device also includes a display circuit 7, which is electrically connected to the MCU management unit 1 through a wire; the display circuit 7 uses an LCD for display, and the LCD includes an 84-segment liquid crystal, which can display a maximum of 9999999.999 kWh of electricity, and the number of decimal places can be set according to user needs. The utility model does not make specific limitations. The display circuit 7 is driven by the MCU management unit 1 to realize the display of 4COM*21SEG driving segment code data.

[0077] Specifically, in this embodiment, see Fig.11 The direct-type DC electric energy metering device also includes a data storage circuit 9, which is electrically connected to the MCU management unit 1 through a wire; the data storage circuit 9 includes a main data storage circuit 9 and a backup data storage circuit 9.

[0078] Specifically, in this embodiment, the main data storage circuit 9 includes a main data memory U13, and pin 1 of the main data memory U13 is connected to the switching power supply 12; pins 2, 3, and 4 of the main data memory U13 are grounded; pin 5 of the main data memory U13 is connected to resistor R11 and resistor R6, respectively, and the other end of the resistor R6 is connected to the MCU management unit 1; pin 6 of the main data memory U13 is connected to resistor R63 and the MCU management unit 1, respectively; pin 7 of the main data memory U13 is connected to resistor R53 and the MCU management Unit 1 is connected; the other ends of the resistors R11, R63 and R53 are connected to the switching power supply 12; the 8 pins of the master data memory U13 are respectively connected to the capacitor C18 and the switching power supply 12, and the other end of the capacitor C18 is grounded; the default storage capacity of the master data memory U13 is 512kbit, which is not specifically limited in the present invention and can be set according to needs. The master data memory circuit is used to store power data, various rate metering data, settlement data, freezing data, and various event record data such as time calibration, cover opening, programming, etc. during the operation of the device.

[0079] Specifically, in this embodiment, the backup data storage circuit 9 includes a backup data storage U14, and the 1st and 2nd pins of the backup data storage U14 are connected to the switching power supply 12; the 3rd and 4th pins of the backup data storage U14 are grounded; the 5th pin of the backup data storage U14 is respectively connected to the resistor R66 and the resistor R7, and the other end of the resistor R7 is connected to the MCU management unit 1; the 6th pin of the backup data storage U14 is respectively connected to the resistor R64 and the MCU management unit 1; the 7th pin of the backup data storage U14 is respectively connected to the resistor R65 and the MCU management unit 1; The other ends of the resistors R66, R64 and R65 are connected to the switching power supply 12; the 8 pins of the backup data storage device U14 are respectively connected to the switching power supply 12 and the capacitor C19, and the other end of the capacitor C19 is grounded; the backup data storage circuit 9 is used to back up various important data in the main data storage to ensure data storage security; the main data storage device U13 and the backup data storage device U14 both support capacity expansion, and the capacity of the memory can be expanded according to user needs. The maximum capacity of the main and backup cards can reach 256Mbit, which can be suitable for various metering, settlement, assessment measurement and metering scenarios.

[0080] Specifically, in this embodiment, see Figure 14-16The direct-type DC electric energy metering device also includes a switching power supply 12; the switching power supply 12 is electrically connected to the MCU management unit 1; the switching power supply 12 includes a first switching power supply, a second switching power supply and a third switching power supply; the first switching power supply is the input conversion part of the switching power supply 12, the input voltage range is 9V-36V DC voltage, and the output is 5V voltage. The first switching power supply is used to provide power for the MCU management unit 1 and peripheral devices; the second switching power supply is used to provide power for the RS485 communication circuit and the CAN communication circuit 11; the third switching power supply is used to provide power for the voltage sampling circuit 2 and the current sampling circuit 3.

[0081] Specifically, in the present embodiment, the first switching power supply includes a switch chip U10, wherein pin 1 of the switch chip U10 is connected to a capacitor C12, and the other end of the capacitor C12 is connected to a resistor R23; pin 6 of the switch chip U10 is respectively connected to a diode D14, a capacitor C6, an inductor L1, and the other end of the resistor R23, the other end of the capacitor C6 is connected to a resistor R10, and the other end of the inductor L1 is respectively connected to a resistor R77, a capacitor C66, a capacitor C11, a capacitor C14, a capacitor C10, and a peripheral device; pin 3 of the switch chip U10 is respectively connected to a resistor R71 and a resistor R72, the other end of the resistor R71 is grounded, and the other end of the resistor R72 is connected to the other end of the resistor R77 One end is connected; pins 4 and 5 of the switch chip U10 are respectively connected to capacitor C23, capacitor CP8, capacitor CP7, diode TVS0 and diode VD1; pin 2 of the switch chip U10, capacitor C23, capacitor CP8, capacitor CP7, diode TVS0, diode D14, resistor R10, capacitor C66, capacitor C11, capacitor C14 and the other end of capacitor C10 are grounded; the first switching power supply is used to convert a DC voltage with an input voltage range of 9V-36V into 5V to power the MCU management unit 1 and peripheral devices; the switch chip U10 adopts a switch chip model LM2842 with a power of 1W, which is not specifically limited in the present invention and can be set according to needs.

[0082] Specifically, in this embodiment, the second switching power supply includes a driving chip U3, and pins 2 and 3 of the driving chip U3 are respectively connected to a capacitor C59 and a ground terminal; the other end of the capacitor C59 is connected to the output terminal of the first switching power supply, that is, connected to the other end of the inductor L1; pins 4, 5, and 6 of the driving chip U3 are respectively connected to pins 3, 2, and 1 of the transformer T1, and pin 5 of the driving chip U3 is also connected to the output terminal of the first switching power supply; pins 4 and 6 of the transformer T1 are respectively connected to a diode D11 and a diode D10, and the diode D11 and the diode D10 are connected to the output terminal of the first switching power supply. The other end of 0 is respectively connected to the RS485 communication circuit, the CAN communication circuit 11, the capacitor C65, the capacitor C71 and the resistor R24; the 5 pins of the transformer T1 are respectively connected to the capacitor C65, the capacitor C71, the other end of the resistor R24 ​​and the ground; the second switching power supply is used to provide power for the RS485 communication circuit and the CAN communication circuit 11; in the utility model, the driver chip adopts the driver chip model VPS8504B, and the transformer adopts the model VPT85BB-01A. The utility model does not make specific limitations and can be set according to needs.

[0083] Specifically, in the present embodiment, the third switching power supply includes a driving chip U4; Pin 2 of the driving chip U4 is respectively connected to the capacitor C60 and the ground terminal, and the other end of the capacitor C60 is connected to the output terminal of the first switching power supply; Pin 4 of the driving chip U4 is connected to Pin 4 of the transformer T2, Pin 5 of the driving chip U4 is respectively connected to Pins 2 and 3 of the transformer T2 and the output terminal of the first switching power supply, and Pin 6 of the driving chip U4 is connected to Pin 1 of the transformer T2; Pin 5 of the transformer T2 is connected to the diode D13, Pin 8 of the transformer T2 is connected to the diode D12, and the other ends of the diodes D12 and D13 are respectively connected to the capacitor C64, the capacitor C69, the resistor R25 and the resistor R13. The 1st and 2nd pins of the voltage regulator U2 are connected; the 6th and 7th pins of the transformer T2 are respectively connected to the capacitor C64, the capacitor C69, the other end of the resistor R25 and the ground; the 5th pin of the voltage regulator U2 is respectively connected to the voltage sampling circuit 2, the current sampling circuit 3, the capacitor C58 and the capacitor C37; the 2nd pin of the voltage regulator U2 is respectively connected to the capacitor C56, the capacitor C37 and the ground; the third switching power supply is used to provide power for the voltage sampling circuit 2 and the current sampling circuit 3; the driving chip U4 adopts the driving chip model VPS5804B, and the transformer T2 adopts the transformer model VPT87BB-01C. The utility model does not make specific restrictions and can be set according to needs.

[0084] Specifically, in this embodiment, the direct-type DC electric energy metering device described in the utility model can directly access the current with a maximum current of up to 400A and a voltage of 1000V, has the function of temperature compensation, and adopts an independently designed high-precision voltage and current sampling circuit 3, which ensures that the measurement accuracy meets the 0.5 level requirement within the full temperature range and the standard range, and solves the problems of small current, poor accuracy and instability of conventional instruments; the communication circuit 11 includes RS485, Bluetooth and CAN bus communication methods, which can meet various occasions of DC detection and measurement, and the verification of electric energy accuracy supports Bluetooth wireless verification method, which is simple and convenient to operate; by sealing the shunt and the base meter as a whole, the fairness and authority of the measurement settlement is guaranteed.

[0085] The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A direct-flow DC electric energy metering device, characterized in that: include: MCU management unit, voltage sampling circuit, current sampling circuit, temperature measurement circuit, communication circuit, hardware data encryption circuit, clock circuit, electric energy pulse output circuit and switching power supply; the MCU management unit is electrically connected to the temperature measurement circuit, communication circuit, clock circuit and pulse output circuit respectively through wires; the voltage sampling circuit is electrically connected to the MCU management unit input through wires; the current sampling circuit is electrically connected to the MCU management unit input through wires; the hardware data encryption circuit is electrically connected to the MCU management unit input through wires; the switching power supply is linearly connected to the MCU management unit, and the switching power supply includes a first switch, a second switching power supply and a third switching power supply; the communication circuit includes a Bluetooth communication circuit, an RS485 communication circuit and a CAN communication circuit.

2. A direct-flow DC electric energy metering device according to claim 1, characterized in that: The voltage sampling circuit includes a resistor RVA, a voltage divider circuit, a resistor RT1, a first anti-aliasing circuit and a sampling chip U16; one end of the voltage divider circuit is respectively connected to the resistor RVA and an external device, and the other end of the voltage divider circuit is respectively connected to the resistor RT1, the first anti-aliasing circuit and the 5th pin of the sampling chip U16; the other end of the resistor RVA is respectively connected to the other end of the resistor RT1, the first anti-aliasing circuit, the 4th pin of the sampling chip U16 and the ground end; the 13th and 14th pins of the sampling chip U16 are connected to the MCU management unit; the 16th pin of the sampling chip U16 is respectively connected to the resistor RL1 and the capacitor CJ2, the other end of the resistor RL1 is connected to the switching power supply, and the other end of the capacitor CJ2 is grounded; wherein the 5th pin of the sampling chip U16 is the IAP pin, the 4th pin of the sampling chip U16 is the IAN pin, the 13th pin of the sampling chip U16 is the RX pin, the 14th pin of the sampling chip U16 is the TX pin, and the 16th pin of the sampling chip U16 is the VDD pin.

3. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The current sampling circuit includes a DC shunt RB0, a second anti-aliasing circuit and a sampling chip U15; one end of the DC shunt RB0 is respectively connected to the positive end of the external device and the second anti-aliasing circuit, and the other end of the DC shunt RB0 is respectively connected to the negative end of the external device and the second anti-aliasing circuit; the second anti-aliasing circuit is respectively connected to pins 4 and 5 of the sampling chip U15; pins 13 and 14 of the sampling chip U15 are connected to the MCU management unit; pin 16 of the sampling chip U15 is respectively connected to a resistor RL2 and a capacitor CJ1, the other end of the resistor RL2 is connected to a switching power supply, and the other end of the capacitor CJ1 is grounded; wherein pin 4 of the sampling chip U15 is an IAN pin, pin 5 of the sampling chip U15 is an IAP pin, pin 13 of the sampling chip U15 is an RX pin, pin 14 of the sampling chip U15 is a TX pin, and pin 16 of the sampling chip U15 is a VDD pin.

4. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The temperature measurement circuit includes a temperature sensor UT1, a resistor R76 and a single-chip microcomputer U88; the DQ end of the temperature sensor UT1 is respectively connected to the resistor R76 and the GPIO port of the single-chip microcomputer U88, and the GND end of the temperature sensor UT1 and the GND end of the single-chip microcomputer U88 are grounded; the VDD end of the single-chip microcomputer U88 and the other end of the resistor R76 are connected to the switching power supply.

5. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The Bluetooth communication circuit is electrically connected to the MCU management unit through a wire; the Bluetooth communication circuit includes a Bluetooth module U1; Pin 5 of the Bluetooth module U1 is connected to the resistor RL1 and the capacitor CL10 respectively, and the other end of the resistor RL1 is connected to the diode D15 and the resistor RL4 respectively; Pin 6 of the Bluetooth module U1 is connected to the resistor RL2 and the capacitor CL11 respectively, and the other end of the resistor RL2 is connected to the diode D17 and the resistor RL5 respectively; Pin 7 of the Bluetooth module U1 is connected to the resistor RL3 and the capacitor CL12 respectively, and the other end of the resistor RL3 is connected to the diode D18 and the resistor RL6 respectively; the other ends of the capacitors CL10, CL11 and CL12 are grounded, and the other ends of the resistors RL4, RL5 and RL6 are connected to pin 1 of the socket JP7; Pins 18 and 19 of the Bluetooth module U1 are connected to the MCU management unit; Pin 23 of the Bluetooth module U1 is connected to a resistor R97 and a capacitor C93, the other end of the capacitor C93 is grounded, and the other end of the resistor R97 is connected to pin 4 of the socket JP7; The 24th and 25th pins of the Bluetooth module U1 are connected to the 2nd and 3rd pins of the socket JP7 respectively; Among them, pin 5 of the Bluetooth module U1 is the P0.03 / AIN1(L) pin, pin 6 of the Bluetooth module U1 is the P0.02 / AIN0 pin, pin 7 of the Bluetooth module U1 is the P0.04 / AIN2 pin, pin 18 of the Bluetooth module U1 is the P0.07 pin, pin 19 of the Bluetooth module U1 is the P0.14 pin, pin 23 of the Bluetooth module U1 is the P0.18 / nRESET pin, pin 24 of the Bluetooth module U1 is the SWCLK pin, and pin 25 of the Bluetooth module U1 is the SWDIO pin.

6. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The RS485 communication circuit is electrically connected to the MCU management unit output through a wire; the RS485 communication circuit includes a communication chip U10; Pins 1 and 4 of the communication chip U10 are connected to the communication isolation circuit; Pins 2 and 3 of the communication chip U10 are connected to pins 2 and 3 of the optocoupler N7 respectively; Pin 5 of the communication chip U10 is connected to the resistor R96 and the ground respectively, the other end of the resistor R96 is connected to pin 7 of the communication chip U10, the resistor RT30, the transient protector V10 and the transient protector V5 respectively, the other end of the resistor RT30 is connected to the MCU management unit, the other end of the transient protector V5 is connected to pin 6 of the communication chip U10, and the other end of the transient protector V10 is grounded; The 6 pins of the communication chip U10 are respectively connected to the resistor R95, the resistor RT79 and the transient protector V11; the other end of the resistor R95 is connected to the switching power supply, the other end of the resistor RT79 is connected to the MCU management unit, and the other end of the transient protector V11 is grounded; The 8 pins of the communication chip U10 are connected to the capacitor C87 and the switch power supply respectively, and the other end of the capacitor C87 is grounded; Among them, pin 1 of the communication chip U10 is the R pin, pin 2 of the communication chip U10 is the RE pin, pin 3 of the communication chip U10 is the DE pin, pin 4 of the communication chip U10 is the D pin, pin 5 of the communication chip U10 is the GND pin, pin 6 of the communication chip U10 is the A pin, pin 7 of the communication chip U10 is the B pin, and pin 8 of the communication chip U10 is the VCC pin.

7. A direct-flow DC electric energy metering device according to claim 6, characterized in that: The CAN communication circuit is electrically connected to the MCU management unit output through a wire; the CAN communication circuit includes a communication chip U89; Pins 1 and 4 of the communication chip U89 are connected to the communication isolation circuit; Pin 3 of the communication chip U89 is connected to the power supply terminal and the capacitor CP41 respectively, and pins 2 and 8 of the communication chip U89 and the other end of the capacitor CP41 are grounded; The 6 pins of the communication chip U89 are respectively connected to the resistor R19, the transient protector V6, the transient protector V13 and the resistor RT1, the other end of the transient protector V13 is respectively connected to the transient protector V12 and the ground, and the other end of the resistor RT1 is connected to the MCU management unit; Pin 7 of the communication chip U89 is respectively connected to the resistor R19, the transient protector V6, the other end of the transient protector V12 and the resistor RT2; the other end of the resistor RT2 is connected to the MCU management unit; Among them, pin 1 of the communication chip U89 is the TXD pin, pin 2 of the communication chip U89 is the VSS pin, pin 3 of the communication chip U89 is the VCC pin, pin 4 of the communication chip U89 is the RXD pin, pin 6 of the communication chip U89 is the CANL pin, pin 7 of the communication chip U89 is the CANH pin, and pin 8 of the communication chip U89 is the Rs pin.

8. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The hardware data encryption circuit includes an encryption chip U17; pin 2 of the encryption chip U17 is respectively connected to pin 7 and the MCU management unit; pin 3 of the encryption chip U17 is respectively connected to pin 6 and the MCU management unit; pins 4 and 5 of the encryption chip U17 are both connected to the MCU management unit; pin 8 of the encryption chip U17 is respectively connected to capacitor C97 and the collector of transistor QD4, the emitter of the transistor QD4 is connected to the power supply end, and the base of the transistor QD4 is connected to the MCU management unit through a resistor R101; wherein, pin 2 of the encryption chip U17 is a MOSI pin, pin 3 of the encryption chip U17 is a MISO pin, pin 4 of the encryption chip U17 is an SSN pin, pin 5 of the encryption chip U17 is an SCK pin, pin 6 of the encryption chip U17 is a MISO pin, pin 7 of the encryption chip U17 is a MOSI pin, and pin 8 of the encryption chip U17 is a VCC pin.

9. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The clock circuit includes a clock chip U84; pin 2 of the clock chip U84 is respectively connected to the MCU management unit and the resistor R49, and the other end of the resistor R49 is respectively connected to the resistor R50, the switching power supply and the pins 1 and 2 of the dual diode D1; pin 6 of the clock chip U84 is respectively connected to the capacitor C52, the pin 3 of the dual diode D1 and the pin 3 of the dual diode D2, the other end of the capacitor C52 is grounded, pins 1 and 2 of the dual diode D2 are connected to the battery BT1, the other end of the battery BT1 is connected to the resistor R26, the other end of the resistor R26 is connected to the switch S1, and the other end of the switch S1 is grounded; wherein, pin 2 of the clock chip U84 is the SCL pin, and pin 6 of the clock chip U84 is the VDD pin.

10. A direct-flow DC electric energy metering device according to any one of claims 1 to 2, characterized in that: The electric energy pulse output circuit includes an optocoupler N11; pin 1 of the optocoupler N11 is connected to a resistor R70, and the other end of the resistor R70 is connected to a switching power supply; pin 2 of the optocoupler N11 is respectively connected to a capacitor CG1 and an external receiving end, pins 3 and 4 of the optocoupler N11 are connected to an MCU management unit, and the other end of the capacitor CG1 is grounded; pin 1 of the optocoupler N11 is an LED anode, pin 2 of the optocoupler N11 is an LED cathode, pin 3 of the optocoupler N11 is an emitter of a photodetector, and pin 4 of the optocoupler N11 is a collector of a photodetector.

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