A wireless dual-core variable frequency power quality analyzer

Abstract

A wireless dual-core variable frequency power quality analyzer relates to the technical field of power quality analyzers, and comprises a shell and a controller. The controller is arranged inside the shell, an incoming line terminal is arranged on the top of the shell, an output terminal is arranged on the bottom, an indicator light, an antenna interface and an infrared communication interface are arranged on the front side of the shell, and the controller comprises a power distribution module, a current and voltage metering sampling module, a data processing module, a microprocessing module and a communication module. Through AD metering sampling, DSP data processing and ARM control, electric energy information with a voltage range of 0 to 600 V, a current range of 0 to 1000 A and a signal frequency range of 0 to 1000 Hz is collected and analyzed, and the accuracy level is 0.5S. The wide range of electric energy information collection can analyze the power quality more comprehensively, and the analysis result is uploaded to a host computer in a LORA wireless communication mode or a 485 communication mode, which solves the problem that the current variable frequency electric energy signal cannot be accurately collected and analyzed. The LORA wireless communication mode broadens the applicable working conditions of the device.

Description

Technical Field

[0001] The invention relates to the technical field of power quality analyzers, and in particular to a wireless dual-core variable frequency power quality analyzer. Background Art

[0002] With the rapid development of science and technology and the national economy, various industrial productions have higher and higher requirements for the power quality of power systems. If the various indicators of power quality deviate from the levels specified by the state, it will cause varying degrees of harm to electrical equipment. In recent years, the extensive use of intelligent power electronic equipment and nonlinear loads has caused increasingly serious power pollution, and power quality has become an issue of increasing concern to the power sector and its users. Good power quality is a necessary condition for the economic, stable and safe operation of the power system, and is also of great significance to the overall benefits of the national economy and the sustainable development of industrial production.

[0003] Existing products, such as the PQ116-2 power quality analyzer of Shanghai Baosteel Anda, the ACR230ELH harmonic analyzer of Shanghai Ankerui, and the electric energy analyzer of Anhui Zhenxing Technology, mainly measure and analyze the voltage, current, active power, reactive power, apparent power, power factor, harmonics and other parameters of the State Grid power frequency signal (50Hz). There are fewer products involving variable frequency signal analysis, and there are problems such as incomplete analysis parameters, low accuracy level (level 1), inconvenient installation, and non-real-time data monitoring. Summary of the invention

[0004] The embodiment of the present invention provides a wireless dual-core variable frequency power quality analyzer, which adopts a DSP+ARM dual-core hardware platform design. The analyzer can collect and analyze power information in a voltage range of 0~600V, a current range of 0~1000A, and a signal frequency range of 0~1000Hz, with an accuracy level of 0.5S. The wide range of power information collection is closer to various operating conditions on site, and the power quality can be analyzed more comprehensively.

[0005] A wireless dual-core variable frequency power quality analyzer comprises a housing and a controller, wherein the controller is arranged inside the housing;

[0006] The top of the housing is provided with an inlet terminal, the bottom of the housing is provided with an output terminal, the output terminal includes a 485 interface and a measurement interface, and the front side of the housing is provided with an indicator light, an antenna interface and an infrared communication interface;

[0007] The controller includes a power distribution module, a current and voltage metering and sampling module, a data processing module, a microprocessing module and a communication module. The input end of the power distribution module is connected to the incoming line end and is externally connected to a power supply. The output end of the power distribution module is divided into two paths, one of which is electrically connected to the current and voltage metering and sampling module, the data processing module, the microprocessing module and the communication module respectively, and the other path provides a negative power supply for the operational amplifier. The input end of the current and voltage metering and sampling module is connected to the incoming line end and is connected to the input voltage. The output end of the current and voltage metering and sampling module is electrically connected to the input end of the data processing module, the output end of the data processing module is electrically connected to the input end of the microprocessing module, and the output end of the microprocessing module is electrically connected to the input end of the communication module.

[0008] As a preferred technical solution of the present invention, the power distribution module includes a flyback switch module and a power conversion module, and the output end of the flyback switch module is electrically connected to the input end of the power conversion module.

[0009] As a preferred technical solution of the present invention, the flyback switch module includes a protection module, a high-frequency transformer coupling module, a DC power supply output module and a monitoring circuit module. The protection module is arranged at the front end of the high-frequency transformer coupling module. The high-frequency transformer coupling module includes two groups of primary coils and secondary coils, one group of the secondary coils is electrically connected to the DC power supply output module, and the monitoring circuit module includes a switching power supply chip and a feedback circuit.

[0010] As a preferred technical solution of the present invention, the current and voltage metering sampling module includes a 2.4M resistor string, a current-type voltage transformer, a sampling resistor and a gain amplifier. The input voltage signal enters the current-type voltage transformer after passing through the 2.4M resistor string. The output end of the current-type voltage transformer passes through the sampling resistor and is amplified 100 times by the gain amplifier before being input to the chip voltage sampling pin of the current and voltage metering sampling module. The input current signal passes through the current-type voltage transformer and is amplified 6.2 times by the gain amplifier before being input to the chip current sampling pin of the current and voltage metering sampling module.

[0011] As a preferred technical solution of the present invention, the communication module includes an RS485 communication module, a LORA wireless communication module and an infrared communication module, the RS485 communication module is electrically connected to the 485 interface, the LORA wireless communication module is electrically connected to the antenna interface, and the infrared communication module is electrically connected to the infrared communication interface.

[0012] As a preferred technical solution of the present invention, the default communication rate of the RS485 communication module and the LORA wireless communication module is 2400 bit / s, the default communication rate of the infrared communication module is 1200 bit / s, and the interface communication complies with the DL / T 645-2007 protocol.

[0013] As a preferred technical solution of the present invention, the measurement interface is externally connected to a dedicated measuring instrument to measure and analyze active power and reactive power parameters of power quality.

[0014] As a preferred technical solution of the present invention, the input end of the microprocessor module is connected to user instructions, and its output end is correspondingly connected to a group of communication modules in the communication module to upload monitoring and analysis data. The microprocessor module is an ARM processor, and the chip model is STM32F103RCT6.

[0015] As a preferred technical solution of the present invention, the current and voltage measurement sampling module is AD sampling, has 8 groups of sampling channels, and the core chip model is ADC7606B.

[0016] As a preferred technical solution of the present invention, the data processing module is connected to the current and voltage measurement sampling module using an SPI parallel data line, the data processing module is a DSP processor, and the chip model is STM32F429VET6.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] (1) Through AD sampling, DSP data processing, and ARM control, the power quality analysis of high voltage, high current, and variable frequency signals (0-1000Hz) is realized with an accuracy level of 0.5S, which solves the current problem that variable frequency power signals cannot be accurately collected and analyzed;

[0019] (2) Use LORA wireless communication or 485 communication to upload to the host computer for data monitoring and analysis. No wiring is required on site. LORA wireless communication broadens the applicable working conditions of the analyzer.

[0020] (3) The AD sampling part and the DSP data processing module use parallel data transmission, which increases the transmission rate by 16 times compared with traditional analyzers.

[0021] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0022] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 A schematic diagram of the structure of a wireless dual-core variable frequency power quality analyzer disclosed in an embodiment of the present invention;

[0025] Figure 2 A communication connection diagram of a wireless dual-core variable frequency power quality analyzer disclosed in an embodiment of the present invention;

[0026] Figure 3 A circuit diagram of a power distribution module disclosed in an embodiment of the present invention;

[0027] Figure 4 A circuit diagram of an output branch of a power distribution module disclosed in an embodiment of the present invention;

[0028] Figure 5 A circuit diagram of a current and voltage measurement sampling module disclosed in an embodiment of the present invention;

[0029] Figure 6 A circuit diagram of eight groups of sampling channels disclosed in an embodiment of the present invention;

[0030] Figure 7 A circuit diagram of current and voltage input disclosed in an embodiment of the present invention;

[0031] Figure 8 A circuit of a data processing module disclosed in an embodiment of the present invention Figure 1 ;

[0032] Fig. 9 A circuit of a data processing module disclosed in an embodiment of the present invention Figure 2 ;

[0033] Fig.10 A circuit of a data processing module disclosed in an embodiment of the present invention Figure 3 ;

[0034] Fig.11 A circuit of a data processing module disclosed in an embodiment of the present invention Figure 4 ;

[0035] Fig.12 A circuit of a data processing module disclosed in an embodiment of the present invention Figure 5 ;

[0036] Fig.13A circuit of a data processing module disclosed in an embodiment of the present invention Figure 6 ;

[0037] Fig.14 A circuit of a microprocessor module disclosed in an embodiment of the present invention Figure 1 ;

[0038] Fig.15 A circuit of a microprocessor module disclosed in an embodiment of the present invention Figure 2 ;

[0039] Fig.16 A circuit of a microprocessor module disclosed in an embodiment of the present invention Figure 3 ;

[0040] Fig.17 A circuit diagram of a LORA wireless communication module disclosed in an embodiment of the present invention;

[0041] Fig.18 A circuit diagram of the RS485 communication module disclosed in an embodiment of the present invention;

[0042] Fig.19 A circuit diagram of an infrared communication module disclosed in an embodiment of the present invention;

[0043] Figure markings: 100-housing; 101-incoming terminal; 102-output terminal; 1021-485 interface; 1022-measurement interface; 103-indicator light; 104-antenna interface; 105-infrared communication interface; 200-controller; 201-power distribution module; 2011-flyback switching power supply module; 20111-protection module; 20112-high frequency transformer coupling module; 20113-DC power supply output module; 20114-monitoring circuit module; 2012-power conversion module; 202-current and voltage metering sampling module; 2021-2.4M resistor string; 2022-current type voltage sensor; 2023-sampling resistor; 2024-gain amplifier; 203-data processing module; 204-microprocessor module; 205-communication module; 2051-RS485 communication module; 2052-LORA wireless communication module; 2053-infrared communication module. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0047] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" 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.

[0048] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0049] Example

[0050] Refer to the attached Figures 1 to 19 As shown, the present invention provides a technical solution: a wireless dual-core variable frequency power quality analyzer, comprising a housing 100 and a controller 200 , wherein the controller 200 is disposed inside the housing 100 .

[0051] Refer to the attached Figure 1 As shown, an input terminal 101 is provided at the top of the shell 100, an output terminal 102 is provided at the bottom of the shell 100, the output terminal 102 includes a 485 interface 1021 and a measurement interface 1022, and an indicator light 103, an antenna interface 104 and an infrared communication interface 105 are provided on the front side of the shell 100.

[0052] In this embodiment, the housing 100 is used to install the controller 200, and the detection wire is connected through the input terminal 101 set on the housing 100 to input current and voltage signals. The indicator light 103 facilitates observation of the operation of the input wire and the detection circuit.

[0053] See attached Figures 2 to 19 As shown, the controller 200 includes a power distribution module 201, a current and voltage metering sampling module 202, a data processing module 203, a microprocessing module 204 and a communication module 205. The input end of the power distribution module 201 is connected to the incoming line terminal 101 and is externally connected to a power supply. The output end of the power distribution module 201 is divided into two paths, one of which is electrically connected to the current and voltage metering sampling module 202, the data processing module 203, the microprocessing module 204 and the communication module 205, and the other path provides a negative power supply for the operational amplifier. The input end of the current and voltage metering sampling module 202 is connected to the incoming line terminal 101 and is connected to the input voltage. The output end of the current and voltage metering sampling module 202 is electrically connected to the input end of the data processing module 203, the output end of the data processing module 203 is electrically connected to the input end of the microprocessing module 204, and the output end of the microprocessing module 204 is electrically connected to the input end of the communication module 205.

[0054] In this embodiment, since the analyzer tests high-voltage AC signals, and each module needs to work in a DC environment, and the working voltages are different, the power distribution module 201 distributes the AC220V power supply into working power supplies of different voltages and transmits them to each module. After the current and voltage metering sampling module 202 collects the power parameters, it enters the data processing module 203, and extracts the static parameters and dynamic parameters of the variable frequency signal, such as voltage, current, power, and 99th harmonics through FFT and wavelet transform, to analyze the power quality. After the data processing module 203 collects and calculates the data, it sends the collected data and analysis results to the microprocessing module 204. The microprocessing module 204 uploads the data through the communication module 205 to monitor the power quality.

[0055] The embodiment of the present invention is also implemented through the following technical solutions.

[0056] In an embodiment of the present invention, the power distribution module 201 includes a flyback switch module 2011 and a power conversion module 2012. The output end of the flyback switch module 2011 is electrically connected to the input end of the power conversion module 2012. The AC220V power supply is output as a 5V DC voltage through the flyback switch module 2011. The 5V DC voltage is divided into two branches in the later stage. Branch one outputs a 3.3V DC voltage through the LM1117-33 chip in the power conversion module 2012 to increase the working power supply for the current and voltage metering sampling module 202, the data processing module 203, the microprocessor module 204 and the communication module 205. Branch two outputs a negative 5V DC voltage through the K7805-500R2 chip in the power conversion module 2012 to provide a negative power supply for the operational amplifier.

[0057] In an embodiment of the present invention, the flyback switch module 2011 includes a protection module 20111, a high-frequency transformer coupling module 20112, a DC power supply output module 20113 and a monitoring circuit module 20114. The protection module 20111 is arranged at the front end of the high-frequency transformer coupling module 20112, and is composed of C1, R83, R84, and R85. When the input voltage is high voltage, the voltage division of R85 increases, and after the pin 5 of the switching power supply chip HF920GS-Z (U2) detects that the voltage is higher than a certain value, the chip is turned off and no longer outputs, thereby protecting the subsequent circuit. The high-frequency transformer coupling module 201 12 includes two groups of primary coils and secondary coils for voltage reduction isolation. One group of the secondary coils is electrically connected to the DC power output module 20113. The DC power output module 20113 consists of D2 and a release circuit for releasing instantaneous high voltage when the power is off. When the power is off, D2 is in the cut-off state. C10 in the release circuit continuously outputs 5V DC voltage to the subsequent stage through the inductor LX5 and the resistor R96. The monitoring circuit module 20114 includes a switching power chip and a feedback circuit. The 6th pin of the switching power chip HF920GS-Z (U2) is the feedback pin, and the 14th pin is the output pin. The feedback circuit selects TL431 as the reference and feedback amplifier. When the output voltage deviates, the optocoupler op1 is turned on, and the current of the pin 6 of the switching power chip HF920GS-Z (U2) changes, thereby affecting the voltage output of the pin 14.

[0058] In an embodiment of the present invention, the current and voltage metering sampling module 202 includes a 2.4M resistor string 2021, a current-type voltage transformer 2022, a sampling resistor 2023 and a gain amplifier 2024. The input voltage signal enters the current-type voltage transformer 2022 after passing through the 2.4M resistor string 2021. The output end of the current-type voltage transformer 2022 passes through the sampling resistor 2023 and is amplified 100 times by the gain amplifier 2024 and then input to the chip voltage sampling pin of the current and voltage metering sampling module 202. The input current signal passes through the current-type voltage transformer 2022 and is amplified 6.2 times by the gain amplifier 2024 and then input to the chip current sampling pin of the current and voltage metering sampling module 202.

[0059] In an embodiment of the present invention, the communication module 205 includes an RS485 communication module 2051, a LORA wireless communication module 2052 and an infrared communication module 2053. The RS485 communication module 2051 is electrically connected to the 485 interface 1021, the LORA wireless communication module 2052 is electrically connected to the antenna interface 104, and the infrared communication module 2053 is electrically connected to the infrared communication interface 105. The RS485 communication module 2051 takes into account high voltage protection and forward driving capabilities. The pull-up and pull-down resistors (R2\R23) of the RS485 communication circuit are designed with 20KΩ resistors. While having driving capabilities, they have low power consumption. The TVS tube (SMBJ8.5CA) is designed to protect differential mode surge voltages, and the voltage is clamped at 6.8V to avoid circuit overvoltage damage. The LORA wireless communication module 2052 adopts the ZM470SX-M module, which can transmit a distance of 1000 meters. The infrared communication module 2053 adopts a reasonable resistance design, and the infrared transmission distance can reach 5 meters.

[0060] In an embodiment of the present invention, the default communication rate of the RS485 communication module 2051 and the LORA wireless communication module 2052 is 2400bit / s, the default communication rate of the infrared communication module 2053 is 1200bit / s, the interface communication complies with the DL / T 645-2007 protocol, and the communication rate standard rate configuration has 1200bit / s, 2400bit / s, 4800bit / s, 9600bit / s, and 19200bit / s optional.

[0061] In the embodiment of the present invention, the measurement interface 1022 is externally connected to a dedicated measuring instrument to measure and analyze active power and reactive power parameters of power quality, thereby providing the analyzer with a wider range of usage functions.

[0062] In an embodiment of the present invention, the input end of the microprocessor module 204 is connected to a user instruction, and its output end is connected to a group of communication modules in the communication module 205 to upload monitoring and analysis data. The microprocessor module 204 is an ARM processor, and the chip model is STM32F103RCT6. This chip is a Cortex-M3 core with a built-in floating-point unit (FPU). The operating voltage range is 2.0 V ~ 3.6 V. The required 1.8V power supply is provided by a built-in voltage regulator. The maximum operating frequency is 168 MHz, and a 64K-byte static SRAM is built-in. A 512K-byte flash memory is built-in. A passive 32.768Hz external crystal oscillator is used to provide a working clock for the MCU after multiplication. The microprocessor module 204 has two 512KB EEPROMs, one EEPROM is used to store 8-way metering related parameters, including calibration data, etc.; the other EEPROM is used to store various types of electrical energy data and backup electrical energy data.

[0063] In the embodiment of the present invention, the current and voltage metering sampling module 202 is AD sampling, has 8 groups of sampling channels, and the core chip model is ADC7606B. The conventional metering chip has 128k sampling points per second. For the high-frequency signal of 1000Hz, the metering chip cannot measure correctly. The ADC7606B chip is a 16-bit, synchronous sampling, analog-to-digital conversion data acquisition system with 800k sampling points per second, which is equivalent to a sampling frequency of 50KHz, which meets the metering and acquisition of high-frequency signals. The ADC7606B chip converts the sampling signal into a set of code streams related to the duty cycle and the signal value, and sends the code stream to the data processing module 203 through the parallel data bus for processing.

[0064] In an embodiment of the present invention, the data processing module 203 is connected to the current and voltage measurement sampling module 202 using an SPI parallel data line. The SPI parallel data transmission has a transmission rate 16 times higher than that of serial data transmission, thereby improving the processing speed of the data processing module 203. The data processing module 203 is DSP processing, and the chip model is STM32F429VET6, with a high-performance ARM Cortex-M4 32-bit RISC core with a main frequency of up to 180MHz. The Cortex-M4 core has a single-precision floating-point arithmetic unit, supports all ARM single-precision data processing instructions and data types, has a set of DSP instructions and a memory protection unit (MPU) for improving application security, integrates high-speed embedded memory and up to 4K bytes of backup SRAM, as well as a large number of enhanced I / O and peripherals, with 3 12-bit ADCs, 2 DACs, 1 low-power RTC, 12 general-purpose 16-bit timers, and 2 32-bit timers.

[0065] Specifically, the working principle of this wireless dual-core variable frequency power quality analyzer is as follows: the detection circuit is connected to the incoming terminal 101 at the top of the shell 100, and is connected to the AC220V power supply. The line connection and the detection and analysis operation status are judged by the indicator light 103. The power supply first passes through the flyback switching power supply module 2011. The switching power supply chip HF920GS-Z (U2) in the monitoring circuit module 20114 is in the on state. The primary coil voltage polarity of the high-frequency transformer coupling module 20112 is positive at the top and negative at the bottom, and the voltage polarity induced by the secondary coil is negative at the top and positive at the bottom. The diode D2 in the DC power supply output module 20113 is turned off, and the voltage is applied to the high-frequency transformer coupling module. On the primary coil of 20112, the current in the coil increases linearly. Since D2 is cut off, the influence of the output load current on the high-frequency transformer coupling module 20112 is blocked. Therefore, at this stage, the energy storage of the high-frequency transformer coupling module 20112 increases with the increase of the input current, and the output capacitor C10 provides an output 5V DC voltage. The switching power supply chip HF920GS-Z (U2) in the monitoring circuit module 20114 is in the off state, and the input current of the high-frequency transformer coupling module 20112 disappears. However, due to the existence of the primary coil inductance, the current of the primary coil cannot change suddenly and still maintains the original direction, resulting in the switching power supply chip HF920GS-Z (U2) The drain output capacitor of the integrated MOS tube is quickly charged, and high-frequency oscillation is generated with the equivalent inductor, generating a spike voltage at the drain of the MOS tube, causing the voltage polarity of the primary coil to suddenly change to negative at the top and positive at the bottom, so that the secondary coil induction is positive at the top and negative at the bottom, and the diode D2 in the DC power output module 20113 is turned on, and the energy stored in the primary coil inductor is transferred and released to the load. There are two branches in the 5V DC voltage rear stage. The 5V DC voltage in branch one outputs a 3.3V DC voltage through the LM1117-33 chip in the power conversion module, which is fed to the current and voltage measurement sampling module 202 chip AD7606B and the data processing module 203 chip STM32F429VET 6. The microprocessor module 204 chip STM32F103RCT6 and the RS485 communication module 2051 chip BL3085A provide working power; the 5V DC voltage in branch 2 outputs a negative 5V DC voltage through the K7805-500R2 chip in the power conversion module to provide a negative power supply for the operational amplifier. After the current and voltage measurement sampling module 202 is powered on, voltage and current sampling is performed. The voltage sampling process is that the voltage of channel A passes through the 2.4M resistor string 2021 (R3~R8) and then enters the input end of PT1 in the current type voltage transformer 2022. PT1 has a rated input of 2mA and a rated output of 2mA. The linear range is 0~1000V and the linearity is ≤ 0.2%, the same current is induced at the output end, and enters the gain amplifier 2024 (LM2902U8) after passing through the 100Ω sampling resistor 2023 (R17). The signal is amplified 100 times and enters the A-channel voltage sampling pin of the chip ADC7606B of the current and voltage measurement sampling module 202. Similarly, the C-channel voltage passes through the 2.4M resistor string 2021 (R10~R15) and enters the input end of PT2 in the current type voltage transformer 2022. PT2 has a rated input of 2mA and a rated output of 2mA. The linear range is 0~1000V, and the linearity is ≤ 0.2%, the same current is induced at the output end, and enters the gain amplifier 2024 (LM2902U8) after passing through the 100Ω sampling resistor 2023 (R18). The signal is amplified 100 times and enters the B-channel voltage sampling pin of the chip ADC7606B of the current and voltage measurement sampling module 202. The current sampling is compatible with the current type voltage transformer 2022 sampling or the Rogowski coil for current sampling. If the current type voltage transformer 2022 is used, the output is the current signal. This signal passes through the 5.1Ω sampling resistor 2023 and enters the gain amplifier 2024 (LM2902U7) for signal amplification 6.2 times and then input to the current sampling pin of the chip ADC7606B of the voltage measurement sampling module 202. If the Rogowski coil is used, the output is the voltage signal. This signal enters the gain amplifier 2024 (LM2 902U7) amplifies the signal by 6.2 times and inputs it to the current sampling pin of the chip ADC7606B of the voltage metering sampling module 202. After the chip ADC7606B of the voltage metering sampling module 202 completes sampling, it enters the chip STM32F429VET6 of the data processing module 203. After FFT and wavelet transform, the static and dynamic parameters of the variable frequency signal, such as voltage, current, power, and 99th harmonics, are extracted to analyze the power quality. After the chip STM32F429VET6 of the data processing module 203 collects and calculates the data, it sends the collected data and analysis results to the chip STM32F103RCT6 of the microprocessing module 204. After receiving the user's instructions, the microprocessing module 204 uploads the data through the communication module 205 according to the user's needs to realize the monitoring of power quality. .

[0066] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wireless dual-core variable frequency power quality analyzer, characterized in that: It comprises a housing (100) and a controller (200), wherein the controller (200) is arranged inside the housing (100); The top of the housing (100) is provided with an inlet terminal (101), the bottom of the housing (100) is provided with an output terminal (102), the output terminal (102) comprises a 485 interface (1021) and a measurement interface (1022), and the front side of the housing (100) is provided with an indicator light (103), an antenna interface (104) and an infrared communication interface (105); The controller (200) comprises a power distribution module (201), a current and voltage measurement sampling module (202), a data processing module (203), a microprocessing module (204) and a communication module (205); an input end of the power distribution module (201) is connected to the incoming line end (101) and is externally connected to a power supply; an output end of the power distribution module (201) is divided into two paths, one of which is respectively connected to the current and voltage measurement sampling module (202), the data processing module (203), the microprocessing module (204) and the communication module (205). The first circuit is electrically connected to the block (205), the other circuit provides a negative power supply for the operational amplifier, the input end of the current and voltage measurement sampling module (202) is connected to the incoming line end (101) and receives the input voltage, the output end of the current and voltage measurement sampling module (202) is electrically connected to the input end of the data processing module (203), the output end of the data processing module (203) is electrically connected to the input end of the micro-processing module (204), and the output end of the micro-processing module (204) is electrically connected to the input end of the communication module (205); The power distribution module (201) comprises a flyback switch module (2011) and a power conversion module (2012), wherein the output end of the flyback switch module (2011) is electrically connected to the input end of the power conversion module (2012); The flyback switch module (2011) comprises a protection module (20111), a high-frequency transformer coupling module (20112), a DC power output module (20113) and a monitoring circuit module (20114); the protection module (20111) is arranged at the front end of the high-frequency transformer coupling module (20112); the high-frequency transformer coupling module (20112) comprises two groups of primary coils and secondary coils, one group of the secondary coils is electrically connected to the DC power output module (20113); and the monitoring circuit module (20114) comprises a switch power chip and a feedback circuit; The current and voltage metering sampling module (202) comprises a 2.4M resistor string (2021), a current-type voltage transformer (2022), a sampling resistor (2023) and a gain amplifier (2024); the input voltage signal passes through the 2.4M resistor string (2021) and enters the current-type voltage transformer (2022); the output end of the current-type voltage transformer (2022) passes through the sampling resistor (2023) and is then amplified 100 times by the gain amplifier (2024) and then input to the chip voltage sampling pin of the current and voltage metering sampling module (202); the input current signal passes through the current-type voltage transformer (2022) and is amplified 6.2 times by the gain amplifier (2024) and then input to the chip current sampling pin of the current and voltage metering sampling module (202); The communication module (205) comprises an RS485 communication module (2051), a LORA wireless communication module (2052) and an infrared communication module (2053); the RS485 communication module (2051) is electrically connected to the 485 interface (1021); the LORA wireless communication module (2052) is electrically connected to the antenna interface (104); and the infrared communication module (2053) is electrically connected to the infrared communication interface (105); The current and voltage measurement sampling module (202) is an AD sampling module having 8 groups of sampling channels, and the core chip model is ADC7606B; The microprocessor module (204) is an ARM processor, and the chip model is STM32F103RCT6; The data processing module (203) is a DSP processor, and the chip model is STM32F429VET6.

2. A wireless dual-core variable frequency power quality analyzer as claimed in claim 1, characterized in that: The default communication rates of the RS485 communication module (2051) and the LORA wireless communication module (2052) are 2400 bit / s, the default communication rate of the infrared communication module (2053) is 1200 bit / s, and the interface communication complies with the DL / T 645-2007 protocol.

3. A wireless dual-core variable frequency power quality analyzer as claimed in claim 1, characterized in that: The measurement interface (1022) is externally connected to a dedicated measuring instrument to measure and analyze active power and reactive power parameters of electric energy quality.

4. A wireless dual-core variable frequency power quality analyzer as claimed in claim 1, characterized in that: The input end of the microprocessing module (204) receives user instructions, and the output end thereof corresponds to a group of communication modules in the communication module (205) for uploading monitoring and analysis data.

5. A wireless dual-core variable frequency power quality analyzer as claimed in claim 1, characterized in that: The data processing module (203) and the current and voltage measurement sampling module (202) are connected using an SPI parallel data line.

Images