Expandable multichannel voltage and current measuring device supporting isolation and non-isolation

Abstract

The invention belongs to the technical field of electrical measurement and testing, and particularly relates to an expandable multi-channel voltage and current measuring device supporting isolation and non-isolation. Comprising an internal auxiliary power supply used for receiving an external power supply and providing stable working voltage for the whole measuring device; the single-chip microcomputer serves as a control core and is responsible for coordinating work of all the modules, collecting signals and processing the signals. The isolation and non-isolation adapter plate connection module supports the plugging of a plurality of acquisition plates through a socket and a connector, automatically identifies the type of a board card through the ID identification function of a resistance network, and transmits data to the single-chip microcomputer through a 485 bus; and the four-channel linear optical coupler isolation circuit provides photoelectric isolation for the collected signals, prevents high voltage from interfering with the system, and ensures linear transmission of the signals at the same time. Through modular design, real-time data processing and intelligent analysis, the measurement efficiency, precision and operation convenience are greatly improved, and the system has a wide application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of electrical measurement and testing, and in particular relates to a multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation. Background Art

[0002] 1. Basic situation of traditional technology:

[0003] With the miniaturization, density, and multi-function of equipment, as well as the shorter and shorter development cycle, it is particularly necessary to quickly and reliably complete the performance test of the equipment with flexibility, especially the current and voltage test related to multiple power supply outputs. At present, the measurement of voltage and current usually relies on traditional test instruments, such as digital multimeters, ammeters, oscilloscopes, etc. These traditional devices are generally only suitable for single-channel measurement, and most of them cannot meet the safety requirements in high voltage and complex interference environments. Especially in situations where high voltage and current change frequently, multiple devices are usually required to work in parallel for measurement, which increases the complexity and cost of the system. In addition, the measurement accuracy, sampling speed, and real-time data processing capabilities of traditional equipment are relatively limited. For example, common digital multimeters and ammeters require manual switching when measuring multiple channels at the same time, and usually do not have signal isolation functions, which makes their measurement effect poor in high voltage and high noise environments. Common traditional test equipment includes:

[0004] Digital multimeter: can measure physical quantities such as voltage, current, impedance, etc., suitable for simple testing of a single channel.

[0005] Oscilloscope: used for higher-precision voltage signal waveform analysis, and usually also supports testing of a single channel or a few channels.

[0006] Ammeter / Voltmeter: Specialized for testing current or voltage, but still limited to a single measurement task, usually requiring switching of measuring instruments.

[0007] Most of these devices are designed as single-channel independent measurement tools, or multiple independent instruments are required for multi-channel testing. The operation is complicated and the test results cannot be interacted in real time. In addition, traditional devices usually cannot automatically respond to changes in voltage and current, the test efficiency is low, and the data recognition function is limited.

[0008] Second, the shortcomings of traditional technology:

[0009] In the past, due to the small number of equipment, large equipment space, and wide production cycle, mechanical single-channel test and detection measures were often used. As time goes by, operators are prone to fatigue, which may lead to incomplete and inaccurate test results of test equipment, and cumbersome data recording. It is very necessary to improve and supplement the traditional equipment power detection technology.

[0010] Although traditional voltage and current test technologies have been widely used, they have obvious shortcomings in multi-channel, isolated measurement, and high-precision sampling, including the following shortcomings:

[0011] (1) Single-channel limitation: Traditional test equipment is usually designed for a single channel. In situations where multiple voltage and current signals need to be tested simultaneously, multiple devices are often required or equipment is frequently switched, which makes the operation complex and cumbersome, increasing the test time and manual operation costs.

[0012] (2) Lack of modularity and scalability: Existing traditional test equipment is usually fixed in design and cannot be flexibly expanded. When additional test channels are needed, it is often necessary to replace or add new independent equipment, which makes it difficult to flexibly combine and configure according to actual needs.

[0013] (3) Measurements lack isolation: Many traditional test equipment lack electrical isolation, which can easily cause electrical interference within the system or damage the equipment when measuring high voltage or current. Especially in complex power systems, ground interference and current return problems can easily affect measurement accuracy.

[0014] (4) Insufficient accuracy and real-time sampling capabilities: Traditional test instruments have low accuracy, especially when performing real-time sampling of high-frequency signals or rapidly changing voltages and currents. They often cannot provide sufficiently high accuracy or fast enough response speeds, and lack effective data processing and analysis functions.

[0015] (5) Weak data processing and identification functions: Traditional equipment usually lacks the ability to process and identify real-time data. For example, when the voltage or current exceeds the set range, there is no timely feedback or alarm. The data storage and management functions are usually relatively simple and cannot perform multi-dimensional data analysis.

[0016] (6) Equipment cost: Since the equipment usually operates independently, each measurement channel requires additional equipment and space, resulting in high test equipment costs and occupying a large amount of working space. It is not suitable for occasions with limited space or requiring efficient testing.

[0017] (7) Complex operation: Multi-channel measurement requires manual adjustment of equipment or frequent replacement of measuring instruments. The operation is cumbersome, prone to errors, and lacks an efficient user interaction interface. Summary of the invention

[0018] The purpose of the present invention is to provide a multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation, so as to solve the above technical problems.

[0019] In order to solve the above technical problems, the present invention provides a multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation, including:

[0020] Internal auxiliary power supply, used to receive external power supply and provide stable working voltage to the entire measuring device;

[0021] The single-chip microcomputer, as the control core, is responsible for coordinating the work of each module, collecting signals and processing them;

[0022] Isolation and non-isolation adapter board connection module, supports plugging and unplugging of multiple acquisition boards through sockets and connectors, automatically identifies the board type through the ID recognition function of the resistor network and transmits data to the microcontroller through the 485 bus;

[0023] 4-channel linear optocoupler isolation circuit provides photoelectric isolation for the collected signals to prevent high voltage from interfering with the system while ensuring linear transmission of the signals;

[0024] Signal conditioning module 1 amplifies, filters and conditions the current and voltage signals to ensure that the signals are suitable for subsequent analog-to-digital conversion;

[0025] Signal conditioning module 2 conditions and processes the current and voltage signals in the non-isolated mode and transmits them to the microcontroller;

[0026] Display and user interface module, which displays the measurement results in real time and provides a user interactive interface through a touch screen or buttons for easy configuration and query;

[0027] The LED matrix display module displays the working status of each acquisition module through LED indicators. Red indicates isolation mode, green indicates non-isolation mode, and off indicates that the channel is not enabled.

[0028] Preferably, the internal auxiliary power supply includes: a chip U1, diodes D1-D2, capacitors C1-C6, resistors R1-R4 and an inductor L1; the BST end of the chip U1 is connected to the diode D1 and one end of the capacitor C1, and the other end of the diode D1 is connected to one end of the capacitor C2 and the capacitor C3, the VIN end of the chip U1 and the input end V_IN; the other ends of the capacitor C2 and the capacitor C3 are grounded, the other end of the capacitor C1 is connected to the SW end of the chip U1, the diode D2 and one end of the inductor L1, the other end of the diode D2 is grounded, the other end of the inductor L1 is connected to one end of the capacitor C4 and the capacitor C5, and the output end V_OUT and one end of the resistor R2, the other ends of the capacitor C4 and the capacitor C5 are grounded, the other end of the resistor R2 is connected to one end of the resistor R4 and the FB end of the chip U1, the other end of the resistor R4 is grounded, the COMP end of the chip U1 is connected to the capacitor C6 and the resistor R3 in sequence and then grounded, and the FREQ end of the chip U1 is connected to the resistor R1 and then grounded.

[0029] Preferably, it also includes a hardware ID identification circuit, specifically including: resistors R30~R37; the resistors R30, R32, R34 and one end of the resistor R34 are connected to the power supply VCC_3V, the other end of the resistor R30 is connected to one end of the resistor R31 and the ID identification model P0, the other end of the resistor R31 is grounded, the other end of the resistor R32 is connected to one end of the resistor R33 and the ID identification model P1, the other end of the resistor R33 is grounded, the other end of the resistor R34 is connected to one end of the resistor R35 and the ID identification model P2, the other end of the resistor R35 is grounded, the other end of the resistor R36 is connected to one end of the resistor R37 and the ID identification model P3, and the other end of the resistor R37 is grounded.

[0030] Preferably, the circuit of the 485 bus includes: a chip U3, resistors R11-R14, diodes D11-D13, a capacitor C11 and a termination matching resistor SW1; the RO terminal of the chip U3 is connected to TXD, the RE terminal and the DE terminal of the chip U3 are connected to TNOW and one end of the resistor R11, the other end of the resistor R11 is grounded, the DI terminal of the chip U3 is connected to RXD, the VCC terminal of the chip U3 is connected to the power supply VCC_3V and one end of the capacitor C11, the other end of the capacitor C11 is connected to one end of the resistor R13 and The other end of the resistor R13 is connected to the B end of the chip U3, one end of the resistor R12, the diode D11 and one end of the diode D12. The other end of the diode D11 is grounded. The other end of the diode D12 is connected to one end of the diode D13, one end of the resistor R14, one end of the termination matching resistor SW1 and the A end of the chip U3. The other end of the termination matching resistor SW1 is connected to the other end of the resistor R12. The other end of the resistor R14 is connected to the power supply VCC_3V. The other end of the diode D13 is grounded.

[0031] Preferably, the circuits of the signal conditioning module 1 and the signal conditioning module 2 are the same, and both include a voltage conditioning circuit and a current conditioning circuit;

[0032] The voltage conditioning circuit includes a chip U7, a capacitor C12 and a resistor R27; the GND terminal of the chip U7 is connected to the power supply VEE and one end of the capacitor C12, the other end of the capacitor C12 is connected to the power supply VDD and the VDD end of the chip U7, the AIN0 end and the AIN1 end of the chip U7 are grounded, the DOUT / DRDY end of the chip U7 is connected to one end of the resistor R27, and the other end of the resistor R27 is connected to the power supply VCC_3V;

[0033] The current conditioning circuit includes: a chip U6, a resistor RI1, a resistor RI2, a resistor RI00 and a capacitor C10; the A0 and A1 terminals of the chip U6 are grounded, the SDA of the chip U6 is connected to the INA_SDA port and one end of the resistor RI2, the other end of the resistor RI2 is connected to one end of the resistor RI1 and the power supply VCC_3V, the other end of the resistor RI1 is connected to the INA_SCL port and the SCL terminal of the chip U6, the VS terminal of U6 is connected to one end of the capacitor C10 and the power supply VCC_3V, the other end of the capacitor C10 and the GND terminal of the chip U6 are grounded, the VIN+ terminal of the chip U6 is connected to one end of the resistor RI00 and the I_IN port, and the other end of the resistor RI00 is connected to the I_OUT port and the VIN- terminal of the chip U6.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1) Improve test efficiency and flexibility: The present invention adopts modular design, connects multiple independent test modules through standard interfaces, and can test multiple voltage and current channels at the same time without switching equipment or frequent operations, which significantly improves test efficiency. Users can flexibly configure and expand channels according to their needs, and easily cope with different test scenarios and needs.

[0036] 2) Support isolation and non-isolation mode: The device can select isolation or non-isolation mode according to the measurement requirements. In high voltage or electrical interference environment, using isolation mode can effectively avoid ground interference between devices, ensuring the accuracy of measurement data and the safety of equipment.

[0037] 3) High-precision real-time sampling and processing: The test module of the present invention has a built-in high-precision analog-to-digital converter (ADC), which can accurately sample voltage and current signals, and process the sampled data in real time through the embedded data processing unit. This design enables the system to capture voltage and current changes more accurately, and is suitable for scenarios with high requirements for high precision and fast response.

[0038] 4) Intelligent data analysis and automatic identification function: The present invention can analyze the collected voltage and current signals in real time, automatically identify the size and fluctuation of the signals, and alarm or automatically record according to the set threshold, thus avoiding manual operation errors and improving the reliability and intelligence level of the system. Users can also customize the identification algorithm and alarm conditions according to their needs.

[0039] 5) Modular design and strong scalability: Through modular interface design, the system of the present invention can expand test channels or modify configurations according to needs, greatly improving the flexibility and scalability of the system. For example, users can easily add additional voltage or current test modules to the existing system without replacing equipment, saving costs.

[0040] 6) Convenient operation and remote monitoring: The device is equipped with a user-friendly operation interface, supports touch screen operation, and provides remote monitoring function. Users can remotely view measurement data, adjust settings, and receive alarms through PC or mobile applications.

[0041] 7) Reduce system cost and space occupation: Through modular design, users only need to purchase the required modules, avoiding unnecessary equipment waste. Multiple channels can be connected through a unified interface, reducing equipment costs and reducing system space occupation.

[0042] 8) Improve the safety and reliability of the system: The system of the present invention has real-time monitoring and alarm functions, which can automatically trigger the alarm mechanism when the current or voltage exceeds the set threshold to ensure the safety of equipment and personnel. In addition, the real-time data storage and processing function helps to ensure the integrity and reliability of the test data and avoid data loss due to human error or equipment failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is the overall functional block diagram of the circuit of a multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation of the present invention.

[0044] Figure 2 It is a power supply circuit diagram of the system of the present invention.

[0045] Figure 3 It is the circuit diagram of the single chip computer system of the present invention.

[0046] Figure 4 It is the hardware ID recognition circuit diagram of the present invention.

[0047] Figure 5 It is the 485 bus circuit diagram of the present invention.

[0048] Figure 6 This is the isolated linear optocoupler circuit diagram of the present invention.

[0049] Figure 7 It is a voltage conditioning circuit diagram of the present invention.

[0050] Figure 8 It is the current conditioning circuit diagram of the present invention.

[0051] Fig. 9 This is the OLED driving circuit diagram of the present invention.

[0052] Fig.10 It is the LED state matrix circuit diagram of the present invention. DETAILED DESCRIPTION

[0053] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the accompanying drawings are in very simplified form and in non-precise proportions, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention.

[0054] like Figure 1 As shown, the embodiment of the present invention provides a multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation, mainly including: the power supply system 1 (internal auxiliary power supply) receives the external power supply and provides a stable working voltage to the entire device. The single-chip microcomputer system 2 is the control core, responsible for coordinating the work of each module, collecting signals and processing them. The isolation and non-isolation adapter board connection module 3 supports the plugging and unplugging of multiple acquisition boards through sockets and connectors, automatically identifies the board type and transmits the data to the single-chip microcomputer through the 485 bus. The 4-channel linear optocoupler isolation circuit 4 provides photoelectric isolation for the collected signal to prevent high voltage from interfering with the system, while ensuring the linear transmission of the signal. The current and voltage signal conditioning circuit 5: amplifies, filters and other conditioning of the current and voltage signals to ensure that the signals are suitable for subsequent analog-to-digital conversion. The current and voltage signal processing and conditioning board 6 of the non-isolated acquisition module conditions and processes the current and voltage signals in the non-isolated mode and transmits them to the single-chip microcomputer. The display and user interface module 7 displays the measurement results in real time, and provides an interactive interface with the user through a touch screen or buttons for easy configuration and query. The LED matrix display module 8 displays the working status of each acquisition module through LED indicator lights. Red indicates isolation mode, green indicates non-isolation mode, and no light indicates that the channel is not enabled.

[0055] The entire system automatically selects isolation or non-isolation mode according to user needs, and collects, processes and displays voltage and current data in real time. Users can intuitively understand the status of the equipment through the display screen and LED matrix to ensure the accuracy and reliability of the data.

[0056] (1) Power supply system

[0057] The power supply system is responsible for providing a stable power supply for the entire measuring device. This module converts the external power supply into the stable voltage required by the device. Figure 2As shown, the internal auxiliary power supply includes: a chip U1, diodes D1-D2, capacitors C1-C6, resistors R1-R4 and an inductor L1; the BST end of the chip U1 is connected to the diode D1 and one end of the capacitor C1, the other end of the diode D1 is connected to one end of the capacitor C2 and the capacitor C3, the VIN end of the chip U1 and the input end V_IN; the other ends of the capacitor C2 and the capacitor C3 are grounded, the other ends of the capacitor C1 are connected to the SW end of the chip U1, the diode D2 and one end of the inductor L1, the other end of the diode D2 is grounded, the other end of the inductor L1 is connected to one end of the capacitor C4 and the capacitor C5, and the output end V_OUT and one end of the resistor R2, the other ends of the capacitor C4 and the capacitor C5 are grounded, the other end of the resistor R2 is connected to one end of the resistor R4 and the FB end of the chip U1, the other end of the resistor R4 is grounded, the COMP end of the chip U1 is connected to the capacitor C6 and the resistor R3 in sequence and then grounded, and the FREQ end of the chip U1 is connected to the resistor R1 and then grounded.

[0058] Input port: receives external power signal, direct current (DC) input.

[0059] Voltage stabilization circuit: The rectifier, filter and step-down circuits convert the input power into stable direct current, ensuring that each module can operate at an appropriate voltage.

[0060] Overload protection: Built-in over-current and over-voltage protection functions. When the input power is abnormal, it automatically cuts off the power supply or adjusts the working state to protect the entire device from damage.

[0061] (2) Single-chip microcomputer system

[0062] like Figure 3 As shown, the single-chip microcomputer system is the control core of the entire measuring device, responsible for performing all data acquisition, processing, display, storage and control tasks.

[0063] Main control microcontroller: responsible for coordinating the work of each module, including data acquisition, issuance of control instructions, signal processing, etc.

[0064] Interface module: used for data transmission and command exchange with other modules (such as display module, data acquisition module, communication module, etc.).

[0065] (3) Isolation and non-isolation adapter board connection module

[0066] This module realizes the flexible access of isolated and non-isolated signal acquisition boards, and aggregates data with the microcontroller through the 485 bus. Figure 4As shown, it also includes a hardware ID identification circuit, specifically including: resistors R30 to R37; the resistors R30, R32, R34 and one end of the resistor R34 are connected to the power supply VCC_3V, the other end of the resistor R30 is connected to one end of the resistor R31 and the ID identification model P0, the other end of the resistor R31 is grounded, the other end of the resistor R32 is connected to one end of the resistor R33 and the ID identification model P1, the other end of the resistor R33 is grounded, the other end of the resistor R34 is connected to one end of the resistor R35 and the ID identification model P2, the other end of the resistor R35 is grounded, the other end of the resistor R36 is connected to one end of the resistor R37 and the ID identification model P3, and the other end of the resistor R37 is grounded. The specific board type connected is identified through the resistor network ID, and data transmission of different acquisition modules is realized.

[0067] Sockets and connectors: The module provides plug-in support for multiple isolated and non-isolated acquisition boards through sockets and connectors, and each channel can independently select isolated or non-isolated mode.

[0068] Resistor network identification: Each inserted acquisition board uses the ID recognition function of the resistor network, allowing the microcontroller to identify the type of inserted board (isolated or non-isolated) and switch the acquisition mode based on the identification result.

[0069] 485 bus communication: The module collects and transmits the collected signal data to the main microcontroller through the 485 bus to ensure accurate data transmission and processing. Figure 5 As shown, 4. The circuit of the 485 bus includes: a chip U3, resistors R11-R14, diodes D11-D13, a capacitor C11 and a termination matching resistor SW1; the RO terminal of the chip U3 is connected to TXD, the RE terminal and the DE terminal of the chip U3 are connected to TNOW and one end of the resistor R11, the other end of the resistor R11 is grounded, the DI terminal of the chip U3 is connected to RXD, the VCC terminal of the chip U3 is connected to the power supply VCC_3V and one end of the capacitor C11, and the other end of the capacitor C11 is connected to one end of the resistor R13 And grounded, the other end of the resistor R13 is connected to the B end of the chip U3, one end of the resistor R12, the diode D11 and one end of the diode D12, the other end of the diode D11 is grounded, the other end of the diode D12 is connected to one end of the diode D13, one end of the resistor R14, one end of the termination matching resistor SW1 and the A end of the chip U3, the other end of the termination matching resistor SW1 is connected to the other end of the resistor R12, the other end of the resistor R14 is connected to the power supply VCC_3V, and the other end of the diode D13 is grounded.

[0070] (4) Channel linear optocoupler isolation circuit

[0071] like Figure 6The isolated linear optocoupler circuit is shown. The module provides electrical isolation function to prevent high voltage signals from interfering with and damaging low voltage parts.

[0072] Optocoupler isolator: Four independent linear optocoupler isolators are used to electrically isolate the signal, and the input signal is transmitted to the control system through photoelectric conversion to prevent the high-voltage input signal from affecting the system.

[0073] Linear output: The optocoupler isolator has a linear response characteristic, which can ensure the linear transmission of voltage and current signals without distortion.

[0074] Anti-interference ability: Optocoupler isolation provides strong anti-interference ability, ensuring stable signal transmission in a high-noise environment.

[0075] (5) Current and voltage signal conditioning circuit of the isolation acquisition module

[0076] This module is used to condition the voltage and current signals to make them suitable for subsequent analog-to-digital conversion (ADC) processing.

[0077] Voltage conditioning circuit: including gain adjustment, filtering and other circuits, adjusts the voltage signal to ensure that its amplitude and linearity are suitable for input to ADC for conversion. Figure 7 As shown, the voltage conditioning circuit includes a chip U7, a capacitor C12 and a resistor R27; the GND terminal of the chip U7 is connected to the power supply VEE and one end of the capacitor C12, the other end of the capacitor C12 is connected to the power supply VDD and the VDD end of the chip U7, the AIN0 and AIN1 terminals of the chip U7 are grounded, the DOUT / DRDY terminal of the chip U7 is connected to one end of the resistor R27, and the other end of the resistor R27 is connected to the power supply VCC_3V.

[0078] Current conditioning circuit: The linearity and amplitude of the current signal are adjusted through circuits such as operational amplifiers to ensure that the ratio between the signal and the actual current value is accurate. Figure 8 As shown, the current conditioning circuit includes: a chip U6, a resistor RI1, a resistor RI2, a resistor RI00 and a capacitor C10; the A0 and A1 terminals of the chip U6 are grounded, the SDA of the chip U6 is connected to the INA_SDA port and one end of the resistor RI2, the other end of the resistor RI2 is connected to one end of the resistor RI1 and the power supply VCC_3V, the other end of the resistor RI1 is connected to the INA_SCL port and the SCL terminal of the chip U6, the VS terminal of the U6 is connected to one end of the capacitor C10 and the power supply VCC_3V, the other end of the capacitor C10 and the GND terminal of the chip U6 are grounded, the VIN+ terminal of the chip U6 is connected to one end of the resistor RI00 and the I_IN port, and the other end of the resistor RI00 is connected to the I_OUT port and the VIN- terminal of the chip U6.

[0079] Signal filtering: Use low-pass, high-pass, band-pass filter and other circuits to filter out external noise and interference to ensure the quality of the input signal.

[0080] Signal gain adjustment: According to the amplitude of the sampled signal, the gain is adjusted to ensure that the signal is within the input range of the ADC, thereby improving the measurement accuracy.

[0081] (6) Current and voltage signal processing and conditioning board of non-isolated acquisition module

[0082] This module is mainly used for the acquisition and conditioning of non-isolated signals, processing of current and voltage signals and data transmission.

[0083] Voltage and current signal processing: Amplify, filter, and convert the received voltage and current signals to ensure that the signals are suitable for sampling by the analog-to-digital converter (ADC).

[0084] Signal conditioning: De-noise the signal to improve the accuracy of data acquisition, and transmit the processed signal to the microcontroller or related modules for further processing.

[0085] Conditioning accuracy and stability: The design of this module ensures the accuracy of signal conditioning and system stability in non-isolated mode, and is suitable for signal acquisition in various low-voltage environments.

[0086] (7) Display and user interface module

[0087] This module is mainly responsible for displaying measurement results and interacting with users. Fig. 9 Shown is the OLED driving circuit.

[0088] Display screen: The measured voltage and current values ​​are displayed through the OLED display, and the working status and alarm information of each channel are provided in real time.

[0089] User input interface: allows users to adjust system parameters (such as range, sampling rate, etc.), view historical data and set alarm thresholds through the touch screen or buttons.

[0090] Alarm indication: When the measured voltage or current exceeds the preset range, the system triggers an audible and visual alarm to alert the user of the abnormal situation.

[0091] (8)LED matrix display module

[0092] The LED matrix module intuitively displays the working status of each inserted current and voltage acquisition module through indicator lights. Fig.10 Shown is the LED status matrix circuit.

[0093] LED status indication: Each acquisition channel displays its working status through an LED light. A red LED indicates that the channel is in isolation mode, a green LED indicates that the channel is in non-isolation mode, and an unlit LED indicates that no acquisition module is inserted into the channel and it is not enabled.

[0094] Intuitive display: Through the LED matrix, users can intuitively view the working status of each acquisition module, helping to quickly locate the device status and ensure the normal operation of the system.

[0095] (9) Working principle

[0096] The working principle of the circuit of the multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation is as follows:

[0097] The power supply system 1 provides a stable working voltage to ensure the normal operation of the entire device. The power input converts the external power supply into a stable DC voltage required by the device through a voltage stabilization circuit for use by each module. The single-chip microcomputer system 2, as the control core, coordinates the work of each module through program control and data acquisition task management. It exchanges information with other modules through the communication interface and performs data processing and display control functions.

[0098] When the user inserts different acquisition modules, the isolation and non-isolation adapter board connection module 3 identifies different module types through the socket and connector, automatically detects the isolation or non-isolation mode of the module with the help of the resistor network ID, and transmits the data of each channel to the single-chip computer system 2 through the 485 bus. In this way, the single-chip computer can dynamically identify and adjust the signal acquisition mode (isolation or non-isolation) according to the inserted module.

[0099] For the collected signal, the 4-channel linear optocoupler isolation circuit 4 provides electrical isolation during signal transmission to prevent the high voltage input signal from affecting the low voltage part. The optocoupler isolator ensures accurate signal transmission through photoelectric conversion.

[0100] Next, the collected signal enters the current and voltage signal conditioning circuit 5, and performs gain adjustment, filtering and denoising on the signal to ensure that the amplitude, linearity and signal-to-noise ratio of the signal meet the requirements of subsequent analog-to-digital conversion, avoiding the influence of poor signal quality on the measurement accuracy.

[0101] For the acquisition in non-isolated mode, the current and voltage signal processing and conditioning board 6 of the non-isolated acquisition module further conditions the signal and converts it into a standard signal suitable for single-chip microcomputer processing. It mainly processes the signal from the non-isolated mode module to ensure its accuracy and stability in the entire signal chain.

[0102] Once the signal is collected and conditioned, the microcontroller 2 is responsible for further processing the signal data and displaying the real-time voltage and current data on the screen through the display and user interface module 7, providing an interactive interface between the user and the device, allowing the setting of parameters such as range and sampling rate.

[0103] The LED matrix display module 8 intuitively displays the working status of each acquisition channel through indicator lights. The status of each channel is identified by a corresponding LED light, a red light indicates that the channel is in isolation mode, a green light indicates non-isolation mode, and an off indicator light indicates that no valid module is inserted into the channel.

[0104] The various modules work together to ensure efficient acquisition, precise conditioning, stable transmission and display of voltage and current signals, and provide users with flexible configuration and intuitive usage experience.

[0105] The multi-channel voltage and current measurement device of the present invention, which can be expanded to support isolation and non-isolation, solves the deficiencies in traditional measurement technology in many aspects, has a high degree of flexibility, accuracy, safety and intelligence, and is suitable for power systems, industrial equipment, electric vehicles, electronic product testing and other fields. Through modular design, real-time data processing and intelligent analysis, the present invention greatly improves the measurement efficiency, accuracy and convenience of operation, and has broad application prospects.

[0106] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation, characterized in that: include: Internal auxiliary power supply, used to receive external power supply and provide stable working voltage to the entire measuring device; The single-chip microcomputer, as the control core, is responsible for coordinating the work of each module, collecting signals and processing them; Isolation and non-isolation adapter board connection module, supports plugging and unplugging of multiple acquisition boards through sockets and connectors, automatically identifies the board type through the ID recognition function of the resistor network and transmits data to the microcontroller through the 485 bus; 4-channel linear optocoupler isolation circuit provides photoelectric isolation for the collected signals to prevent high voltage from interfering with the system while ensuring linear transmission of the signals; Signal conditioning module 1 amplifies, filters and conditions the current and voltage signals to ensure that the signals are suitable for subsequent analog-to-digital conversion; Signal conditioning module 2 conditions and processes the current and voltage signals in the non-isolated mode and transmits them to the microcontroller; Display and user interface module, which displays the measurement results in real time and provides a user interactive interface through a touch screen or buttons for easy configuration and query; The LED matrix display module displays the working status of each acquisition module through LED indicators. Red indicates isolation mode, green indicates non-isolation mode, and off indicates that the channel is not enabled.

2. A multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation as claimed in claim 1, characterized in that: The internal auxiliary power supply includes: a chip U1, diodes D1-D2, capacitors C1-C6, resistors R1-R4 and an inductor L1; the BST end of the chip U1 is connected to the diode D1 and one end of the capacitor C1, the other end of the diode D1 is connected to one end of the capacitor C2 and the capacitor C3, the VIN end of the chip U1 and the input end V_IN; the other ends of the capacitor C2 and the capacitor C3 are grounded, the other ends of the capacitor C1 are connected to the SW end of the chip U1, the diode D2 and one end of the inductor L1, the other end of the diode D2 is grounded, the other end of the inductor L1 is connected to one end of the capacitor C4 and the capacitor C5, and the output end V_OUT and one end of the resistor R2, the other ends of the capacitor C4 and the capacitor C5 are grounded, the other end of the resistor R2 is connected to one end of the resistor R4 and the FB end of the chip U1, the other end of the resistor R4 is grounded, the COMP end of the chip U1 is connected to the capacitor C6 and the resistor R3 in sequence and then grounded, and the FREQ end of the chip U1 is connected to the resistor R1 and then grounded.

3. A multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation as claimed in claim 1, characterized in that: It also includes a hardware ID identification circuit, specifically including: resistors R30~R37; the resistors R30, R32, R34 and one end of the resistor R34 are connected to the power supply VCC_3V, the other end of the resistor R30 is connected to one end of the resistor R31 and the ID identification model P0, the other end of the resistor R31 is grounded, the other end of the resistor R32 is connected to one end of the resistor R33 and the ID identification model P1, the other end of the resistor R33 is grounded, the other end of the resistor R34 is connected to one end of the resistor R35 and the ID identification model P2, the other end of the resistor R35 is grounded, the other end of the resistor R36 is connected to one end of the resistor R37 and the ID identification model P3, and the other end of the resistor R37 is grounded.

4. A multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation as claimed in claim 1, characterized in that: The circuit of the 485 bus includes: a chip U3, resistors R11-R14, diodes D11-D13, a capacitor C11 and a termination matching resistor SW1; the RO terminal of the chip U3 is connected to TXD, the RE terminal and the DE terminal of the chip U3 are connected to TNOW and one end of the resistor R11, the other end of the resistor R11 is grounded, the DI terminal of the chip U3 is connected to RXD, the VCC terminal of the chip U3 is connected to the power supply VCC_3V and one end of the capacitor C11, and the other end of the capacitor C11 is connected to one end of the resistor R13 and grounded The other end of the resistor R13 is connected to the B end of the chip U3, one end of the resistor R12, the diode D11 and one end of the diode D12, the other end of the diode D11 is grounded, the other end of the diode D12 is connected to one end of the diode D13, one end of the resistor R14, one end of the termination matching resistor SW1 and the A end of the chip U3, the other end of the termination matching resistor SW1 is connected to the other end of the resistor R12, the other end of the resistor R14 is connected to the power supply VCC_3V, and the other end of the diode D13 is grounded.

5. A multi-channel voltage and current measurement device that can be expanded to support isolation and non-isolation as claimed in claim 1, characterized in that: The circuits of the signal conditioning module 1 and the signal conditioning module 2 are the same, and both include a voltage conditioning circuit and a current conditioning circuit; The voltage conditioning circuit includes a chip U7, a capacitor C12 and a resistor R27; the GND terminal of the chip U7 is connected to the power supply VEE and one end of the capacitor C12, the other end of the capacitor C12 is connected to the power supply VDD and the VDD end of the chip U7, the AIN0 end and the AIN1 end of the chip U7 are grounded, the DOUT / DRDY end of the chip U7 is connected to one end of the resistor R27, and the other end of the resistor R27 is connected to the power supply VCC_3V; The current conditioning circuit includes: a chip U6, a resistor RI1, a resistor RI2, a resistor RI00 and a capacitor C10; The A0 and A1 terminals of the chip U6 are grounded, the SDA of the chip U6 is connected to the INA_SDA port and one end of the resistor RI2, the other end of the resistor RI2 is connected to one end of the resistor RI1 and the power supply VCC_3V, the other end of the resistor RI1 is connected to the INA_SCL port and the SCL terminal of the chip U6, the VS terminal of U6 is connected to one end of the capacitor C10 and the power supply VCC_3V, the other end of the capacitor C10 and the GND terminal of the chip U6 are grounded, the VIN+ terminal of the chip U6 is connected to one end of the resistor RI00 and the I_IN port, and the other end of the resistor RI00 is connected to the I_OUT port and the VIN- terminal of the chip U6.

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