Wireless communication type multifunctional electric power measurement and control instrument

Abstract

The utility model discloses a wireless communication type multifunctional electric power measurement and control instrument, which relates to the technical field of electric power system measurement and monitoring, and is characterized in that a CPU (central processing unit) control unit, a WIFI (wireless fidelity) module, a sampling unit, a metering unit, a display unit and a data storage unit are arranged in an instrument body, the metering unit transmits electric energy parameter data measured by the sampling unit to the CPU control unit, a band-pass filter circuit is arranged between the WIFI module and the CPU control unit, the WIFI module supports a high data transmission rate, so that the electric power meter can transmit data more quickly, the band-pass filter circuit filters out irrelevant noise and interference, and the data transmission efficiency is improved. The influence of interference of other frequency bands on WIFI communication is reduced, and the reliability and stability of WIFI communication and the quality of WIFI signals are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power system measurement and monitoring, in particular to a wireless communication type multifunctional power measurement and control instrument. Background Art

[0002] The multifunctional power measurement and control instrument is a power measurement and monitoring device that integrates multiple functions. It is used to measure, monitor and control various electric energy parameters in the power system, and to collect, process and analyze data. It is usually used in the monitoring, protection, energy saving and management of the power system.

[0003] Most of the existing power measurement and control instruments use RS485 communication. RS485 communication adopts a multi-master-slave structure. Only one master device can be connected to each communication line. RS485 communication requires the use of special twisted pair cables, which require high cable quality. In addition, the RS485 communication rate is generally low, and can only reach 10Mbps at most. Therefore, in wireless communication systems that require high-speed data transmission to connect multiple devices, the existing RS485 communication method does not meet the requirements. Utility Model Content

[0004] 1) Technical issues solved

[0005] The purpose of the utility model is to make up for the deficiencies of the prior art and to provide a wireless communication type multifunctional electric power measurement and control instrument.

[0006] 2) Technical solution

[0007] To achieve the above object, the utility model provides the following technical solution: a wireless communication type multifunctional electric power measurement and control instrument, comprising a CPU control unit arranged in the instrument body, the CPU control unit being connected to a power supply, comprising:

[0008] A WIFI module is communicatively connected to the CPU control unit and electrically connected to the power supply, and a bandpass filter circuit is provided between the WIFI module and the CPU control unit;

[0009] A metering unit, connected in communication with the CPU control unit;

[0010] A display unit is communicatively connected with the CPU control unit.

[0011] Furthermore, the input end of the band-pass filter circuit is connected to the output end of the CPU control unit, and the output end of the band-pass filter circuit is connected to the input end of the WIFI module.

[0012] Furthermore, the bandpass filter circuit includes a resistor R5, a resistor R6, a resistor R7, a capacitor C3, a capacitor C4, a capacitor C5 and an op amp AR1, one end of the resistor R6 is connected to the output end of the CPU control unit, the other end of the resistor R6 is connected in series with the capacitor C5 and then connected to the inverting input end of the op amp AR1, the inverting input end of the op amp AR1 is connected to the output end of the op amp AR1 and one end of the capacitor C3 through the resistor R5 and capacitor C4 connected in parallel, the other end of the capacitor C3 is connected to the input end of the WIFI module, wherein the resistor R5 and the capacitor C5 are connected in series, the capacitor C4 and the capacitor C5 are connected in parallel, the in-phase input end of the op amp AR1 is grounded, and the capacitor C4 is grounded through the resistor R7.

[0013] Furthermore, a power management unit is provided between the CPU control unit and the power supply, the power management unit is communicatively connected with the CPU control unit, and the power management unit is electrically connected with the power supply.

[0014] Furthermore, the display unit includes a display screen and a driving circuit, the display screen is electrically connected to the driving circuit, the driving circuit is connected to the CPU control unit, and the driving circuit is used to convert data in the CPU control unit into digital signals and transmit them to the display screen.

[0015] Furthermore, the metering unit is electrically connected to a sampling unit, and the metering unit transmits the collected data of the sampling unit to the CPU control unit.

[0016] Furthermore, the WIFI module is an ESP8266-12F module.

[0017] Furthermore, the RST pin of the WIFI module is connected to the resistor R1, the ADC pin is connected to the resistor R2, the resistor R1 and the resistor R2 are connected in parallel and grounded through the capacitor C1.

[0018] Furthermore, the VCC pin of the WIFI module is connected to the capacitor C2 and then to ground, and the GPIO15 pin of the WIFI module is connected to the resistor R8 and then to the GND pin in parallel to ground.

[0019] Furthermore, the TXD0 pin of the WIFI module is connected to the receiving terminal RXD of the CPU control unit after being connected to the resistor R3.

[0020] 3) Beneficial effects:

[0021] Compared with the prior art, the utility model has the following beneficial effects:

[0022] The utility model provides wireless communication function through the WIFI module, allowing the power meter to communicate with other devices (such as routers, mobile phones, computers) through a wireless network, eliminating the need for wiring and physical connections required for traditional wired connections, making installation and maintenance more convenient, and the WIFI module supports a higher data transmission rate, allowing the power meter to transmit data faster, which is very important for applications that require real-time monitoring and rapid transmission of large amounts of data.

[0023] The WIFI module is connected to a bandpass filter circuit to filter out signals that are not within the WIFI communication frequency band and reduce noise and interference that are not related to the WIFI communication frequency band, thereby reducing the impact of interference from other frequency bands on WIFI communication and improving the reliability and stability of WIFI communication and the quality of WIFI signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a principle block diagram of the utility model;

[0025] Figure 2 This is a circuit diagram of the WIFI module in the utility model;

[0026] In the figure: 1. CPU control unit; 2. Metering unit; 3. Sampling unit; 4. WIFI module; 5. Power management unit; 6. Power supply; 7. Display unit; 8. Data storage unit. DETAILED DESCRIPTION

[0027] 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 in 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.

[0028] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0029] Combination Figure 1 to Figure 2A wireless communication type multifunctional electric power measurement and control instrument shown in the figure includes a CPU control unit 1 arranged in the instrument body, the CPU control unit 1 is connected to a power supply 6, and also includes a WIFI module 4, a metering unit 2 and a display unit 7, wherein the CPU control unit 1 is specifically STM32F0; the WIFI module 4 is specifically ESP8266-12F; the metering unit 2 is specifically STPM32; the display unit 7 is specifically a display screen and a TFT LCD drive circuit; the TFT LCD drive circuit is connected to the STM32F0 through an RGB interface to display graphics and digital data on the display screen.

[0030] Specifically, Figure 1 As shown, the WIFI module 4 is communicatively connected to the CPU control unit 1 and electrically connected to the power supply 6. A bandpass filter circuit is provided between the WIFI module 4 and the CPU control unit 1. The bandpass filter circuit can selectively pass signals within the WIFI communication frequency band and filter out signals in other frequency bands, thereby eliminating signal interference irrelevant to WIFI communication and improving the reliability and stability of communication.

[0031] like Figure 1 As shown, the metering unit 2 is electrically connected to the sampling unit 3. The sampling unit 3 is specifically a current sensor and a voltage sensor, which converts the current and voltage into a voltage or current signal proportional to the current and transmits it to the metering unit 2. The metering unit 2 is communicatively connected to the CPU control unit 1, and performs bidirectional data transmission with the CPU control unit 1 through the SPI interface. The measured electric energy parameter data is transmitted to the CPU control unit 1 through the metering unit 2 for processing and analysis. The CPU control unit 1 can also send control commands to the metering unit 2 and obtain data.

[0032] like Figure 1 As shown, the display screen in the display unit 7 is connected to the CPU control unit 1 through a TFT LED driving circuit. The TFT LED driving circuit is responsible for converting the display data generated by the CPU control unit 1 into a signal suitable for the display screen, and connecting to the display screen through an SPI interface, thereby displaying the measured electric energy data on the display screen.

[0033] like Figure 1 As shown, a power management unit 5 is arranged between the CPU control unit 1 and the power supply 6. The power management unit 5 is specifically TPS65218. The power management unit 5 is communicatively connected with the CPU control unit 1. The power management unit 5 is electrically connected with the power supply 6. When the power management unit 5 detects an abnormal situation, such as overcurrent, overvoltage, undervoltage and overheating, the electrical measurement and control instrument will be powered off and an alarm will be issued.

[0034] like Figure 1As shown, the CPU control unit 1 is also connected to a data storage unit 8, which is specifically a Flash memory. The Flash memory is a non-volatile memory that can maintain data integrity after the electrical measurement and control instrument loses power.

[0035] like Figure 2 As shown, the input end of the bandpass filter circuit is connected to the output end TXD of the CPU control unit 1 , and the output end of the bandpass filter circuit is connected to the input end RXD0 of the WIFI module 4 .

[0036] like Figure 2 As shown, the bandpass filter circuit includes a resistor R5, a resistor R6, a resistor R7, a capacitor C3, a capacitor C4, a capacitor C5 and an op amp AR1, one end of the resistor R6 is connected to the output end of the CPU control unit 1, the other end of the resistor R6 is connected in series with the capacitor C5 and then connected to the inverting input end of the op amp AR1, the inverting input end of the op amp AR1 is connected to the output end of the op amp AR1 and one end of the capacitor C3 through the resistor R5 and the capacitor C4 connected in parallel, the other end of the capacitor C3 is connected to the input end of the WIFI module 4, wherein the resistor R5 and the capacitor C5 are connected in series, the capacitor C4 and the capacitor C5 are connected in parallel, the in-phase input end of the op amp AR1 is grounded, and the capacitor C4 is grounded through the resistor R7.

[0037] In the above structure, the resistor R6 and the capacitor C5 are connected in series to the inverting input terminal of the operational amplifier AR1. The resistor R6 is used to limit the current of the input signal and provide a suitable input impedance to ensure the matching between the signal source and the operational amplifier AR1. The capacitor C5 is used to provide DC isolation to prevent any DC bias from entering the operational amplifier.

[0038] The inverting input terminal of the operational amplifier AR1 is connected to the output terminal of the operational amplifier AR1 and one end of the capacitor C3 through a parallel resistor R5 and a capacitor C4. The parallel connection of the resistor R5 and the capacitor C4 forms a feedback network for determining the center frequency and bandwidth of the filter. The output signal of the operational amplifier AR1 is returned to the inverting input terminal through the feedback network, forming an active bandpass filter, which enhances the signal transmission within a specific frequency range.

[0039] The capacitor C3 is connected to the input end of the WIFI module 4. The capacitor C3 is used to directly connect the filtered signal to the input end of the WIFI module 4 to ensure that the signal transmitted to the WIFI module 4 is of good quality;

[0040] Capacitor C4 is connected to ground through resistor R7. The series connection of capacitor C4 and resistor R7 provides an additional low-pass filter for further filtering out high-frequency noise and interference.

[0041] The non-inverting input terminal of the operational amplifier AR1 is grounded. Grounding the non-inverting input terminal of the operational amplifier can suppress the influence of common-mode noise and improve the anti-interference ability of the filter circuit.

[0042] like Figure 2 As shown, the RST pin of the WIFI module 4 is connected to a 10K resistor R1 for isolating the RST pin from other circuits, and the ADC pin is connected to a 10K resistor R2 for isolating the ADC pin from other circuits and providing a resistor voltage divider function. The resistors R1 and R2 are connected in parallel and grounded through a capacitor C1. The capacitor C1 is 10μF. This connection method can form an RC filter circuit for filtering out interference and noise.

[0043] like Figure 2 As shown, the VCC pin of the WIFI module 4 is connected to capacitor C2 and then grounded. Capacitor C2 is a 100nF ceramic capacitor. This connection method can provide a low impedance path, so that high-frequency noise and interference can bypass the ESP8266 module through capacitor C2, thereby maintaining the stability of the power supply 6 of the VCC pin and reducing the impact on other circuits.

[0044] like Figure 2 As shown, the GPIO15 pin of the WIFI module 4 is connected to a 10K resistor R8, and the other end of the resistor R8 is connected in parallel with the GND pin, that is, connected to the ground at the same time. This connection method can pull the GPIO15 pin down to the ground GND potential, thereby controlling the boot mode of ESP8266. In the boot mode, ESP8266 can load a program or firmware from an external device (such as a serial port or flash memory). The resistor R8 provides an appropriate resistance voltage division while maintaining the stability of the boot mode.

[0045] like Figure 2 As shown, the TXD0 pin of the WIFI module 4 is connected to the resistor R3, and the other end of the resistor R3 is connected to the receiving end RXD pin of the CPU control unit 1. This connection method allows ESP8266 to send data through the TXD0 pin, and the CPU control unit 1 receives data through its receiving end RXD pin to achieve serial communication. The role of the resistor R3 is to limit the current and protect the pin and circuit.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the description and drawings of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wireless communication type multifunctional electric power measurement and control instrument, comprising a CPU control unit (1) arranged in an instrument body, wherein the CPU control unit (1) is connected to a power supply (6), characterized in that: include: A WIFI module (4) is communicatively connected to the CPU control unit (1) and electrically connected to the power supply (6); a bandpass filter circuit is provided between the WIFI module (4) and the CPU control unit (1); A metering unit (2) is communicatively connected to the CPU control unit (1); The display unit (7) is communicatively connected with the CPU control unit (1).

2. A wireless communication type multifunctional electric power measurement and control instrument according to claim 1, characterized in that: The input end of the bandpass filter circuit is connected to the output end of the CPU control unit (1), and the output end of the bandpass filter circuit is connected to the input end of the WIFI module (4).

3. A wireless communication type multifunctional electric power measurement and control instrument according to claim 2, characterized in that: The bandpass filter circuit comprises a resistor R5, a resistor R6, a resistor R7, a capacitor C3, a capacitor C4, a capacitor C5 and an op amp AR1, wherein one end of the resistor R6 is connected to the output end of the CPU control unit (1), the other end of the resistor R6 is connected in series with the capacitor C5 and then connected to the inverting input end of the op amp AR1, the inverting input end of the op amp AR1 is connected to the output end of the op amp AR1 and one end of the capacitor C3 through the resistor R5 and the capacitor C4 connected in parallel, the other end of the capacitor C3 is connected to the input end of the WIFI module (4), wherein the resistor R5 and the capacitor C5 are connected in series, the capacitor C4 and the capacitor C5 are connected in parallel, the inverting input end of the op amp AR1 is grounded, and the capacitor C4 is grounded through the resistor R7.

4. A wireless communication type multifunctional electric power measurement and control instrument according to claim 3, characterized in that: A power management unit (5) is provided between the CPU control unit (1) and the power supply (6); the power management unit (5) is communicatively connected to the CPU control unit (1); and the power management unit (5) is electrically connected to the power supply (6).

5. A wireless communication type multifunctional electric power measurement and control instrument according to claim 1, characterized in that: The metering unit (2) is electrically connected to a sampling unit (3), and the metering unit (2) transmits the collected data of the sampling unit (3) to the CPU control unit (1).

6. A wireless communication type multifunctional electric power measurement and control instrument according to claim 1, characterized in that: The display unit (7) comprises a display screen and a drive circuit, the display screen is electrically connected to the drive circuit, the drive circuit is connected to the CPU control unit (1), and the drive circuit is used to convert data in the CPU control unit (1) into digital signals and transmit them to the display screen.

7. A wireless communication type multifunctional electric power measurement and control instrument according to claim 1, characterized in that: The WIFI module (4) is an ESP8266-12F module.

8. A wireless communication type multifunctional electric power measurement and control instrument according to claim 7, characterized in that: The RST pin of the WIFI module (4) is connected to a resistor R1, the ADC pin is connected to a resistor R2, the resistor R1 and the resistor R2 are connected in parallel and are grounded via a capacitor C1.

9. A wireless communication type multifunctional electric power measurement and control instrument according to claim 7, characterized in that: The VCC pin of the WIFI module (4) is connected to the capacitor C2 and then to ground, and the GPIO15 pin of the WIFI module (4) is connected to the resistor R8 and then to the GND pin in parallel to ground.

10. A wireless communication type multifunctional electric power measurement and control instrument according to claim 7, characterized in that: The TXD0 pin of the WIFI module (4) is connected to the receiving end RXD of the CPU control unit (1) after being connected to the resistor R3.

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