Six-channel direct current standard meter

Abstract

The utility model discloses a six-channel direct-current standard meter, which comprises a main control unit, six groups of acquisition units, a large-current acquisition unit, a human-computer interface display unit, a power supply unit and a communication unit, and is characterized in that the six groups of acquisition units and the large-current acquisition unit are electrically connected with the main control unit through a standard bus interface; the main control unit is electrically connected with the human-computer interface display unit and the communication unit, and the main control unit is provided with a first programmable logic chip, a second programmable logic chip and a third programmable logic chip; the first programmable logic chip is used for generating six paths of electric energy pulses; and the main control unit reads ADC data of the acquisition unit through a data bus, obtains voltage and current values after digital filtering, and generates corresponding six paths of electric energy pulses for verification of a to-be-verified meter. The utility model provides a six-channel high-precision direct-current standard electric energy meter which can measure six paths of large voltages, six paths of small voltages and one path of large current at the same time.

Description

Technical Field

[0001] This utility model relates to the technical field of standard meters in DC energy meter calibration devices, specifically to a six-channel DC standard meter. Background Technology

[0002] Currently, existing DC energy meter calibration devices are used to calibrate various types of DC energy meters, such as direct DC meters, indirect DC meters, and shunts. DC energy meters come in many varieties, including not only high-current meters but also various small-signal meters. As a core component of metering, the DC standard energy meter needs to meet the calibration requirements of all types of energy meters.

[0003] Most DC standard energy meters are single-channel standard meters. When used in multi-position DC calibration devices, they are mostly installed in a single-channel manner, directly on the meter position; and they use a standard source method, which is built into the voltage and current source.

[0004] The following problems exist with DC standard energy meters: 1) Since the standard device mentioned in the DC energy meter calibration device does not have a display component, the measured value cannot be directly viewed. 2) Using a single-channel standard meter requires designing a main control chip for each channel, with independent sampling, metering, and communication, which greatly increases the cost. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a six-channel DC standard meter, which solves the shortcomings of existing DC energy meter calibration devices that lack a display component, making it impossible to directly view the measured values; and the fact that using a single-channel standard meter requires designing a main control chip for each channel, with independent sampling, measurement, and communication, which significantly increases costs.

[0006] The technical solution adopted by this utility model is as follows:

[0007] A six-channel DC standard meter includes: a main control unit, six sets of acquisition units, a high-current acquisition unit, a human-machine interface display unit, a power supply unit, and a communication unit. The six sets of acquisition units and the high-current acquisition unit are electrically connected to the main control unit via a standard bus interface. Each acquisition unit is equipped with an analog-to-digital converter. The main control unit is electrically connected to the human-machine interface display unit and the communication unit. The main control unit is equipped with a first programmable logic chip, a second programmable logic chip, and a third programmable logic chip. The first programmable logic chip is used to generate six power pulses. The main control unit reads the ADC data from the acquisition units via a data bus, performs digital filtering to obtain voltage and current values, and generates the corresponding six power pulses for the calibration of the meter under test.

[0008] Optionally, the power supply unit is electrically connected to the main control unit, six sets of acquisition units, a high-current acquisition unit, a human-machine interface display unit, and a communication unit.

[0009] Optionally, the second programmable logic chip is used to convert the 13-channel ADC serial data into parallel data, and the processor can quickly read each group of data separately.

[0010] Optionally, the third programmable logic chip is used to generate a 25.6kHz sampling frequency signal, and the ADC converts data according to the signal.

[0011] Optionally, each acquisition unit includes one high voltage and one low voltage, with the high voltage using a precision resistor voltage divider.

[0012] Optionally, the main control unit employs a 32-bit ARM high-speed processor.

[0013] Optionally, the 32-bit ARM high-speed processor has a maximum clock speed of 200MHz.

[0014] Optionally, the human-machine display section adopts a high-definition 7-inch capacitive touch screen.

[0015] Optionally, the human-machine display unit is used to display the voltage, current, power, and parameter settings of the six channels.

[0016] Optionally, the measurement range of the high current acquisition unit is 0-1000A.

[0017] Optionally, the ARM processor outputs the measurement data to the display unit. Beneficial effects

[0018] This invention proposes a six-channel high-precision DC standard energy meter, capable of simultaneously measuring six high-voltage channels, six low-voltage channels, and one high-current channel. Each channel is isolated from the others and does not interfere with each other. It can simultaneously calibrate six direct DC meters, indirect DC meters, or shunts.

[0019] This utility model adopts a plug-in card design, which reduces internal wiring, simplifies installation, and can be configured as a 1-6 channel DC standard meter, facilitating the design of calibration devices.

[0020] 3. The data acquisition card in this utility model also adopts a standard data interface, which can be expanded to other types of measurement methods as needed. Attached image description:

[0021] Figure 1 This is a logic flowchart of the six-channel DC standard meter of Embodiment 1 of this utility model;

[0022] Figure 2 This is a system architecture diagram of the ARM processor of the main control unit of the six-channel DC standard meter in Embodiment 1 of this utility model;

[0023] Figure 3This is a signal processing system architecture diagram of the standard definition adapter interface of the six-channel DC standard meter in Embodiment 1 of this utility model;

[0024] Figure 4 This is a logic flowchart of the linear transformer of the six-channel DC standard meter in Embodiment 1 of this utility model;

[0025] Figure 5 This is a top view of the six-channel DC standard meter of Embodiment 1 of this utility model.

[0026] The labels for the attached figures are as follows:

[0027] 1. Main control unit, 2. Power supply unit, 3. Standard defined adapter interface. Detailed implementation method:

[0028] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0029] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" or "linked" should be interpreted broadly, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0030] In the technical specifications of high-precision DC standard meters in this field, "high current" usually refers to the 600A level, while "high voltage" in standard meters generally refers to the 1000V level.

[0031] Example 1

[0032] The technical solution adopted by this utility model is as follows:

[0033] like Figure 1 , Figure 5As shown, this utility model discloses a six-channel DC standard meter, including: a main control unit 1, six sets of acquisition units, a high-current acquisition unit, a human-machine interface display unit, a power supply unit, and a communication unit. The six sets of acquisition units and the high-current acquisition unit are electrically connected to the main control unit through a standard bus interface. The main control unit is electrically connected to the human-machine interface display unit and the communication unit. The main control unit is equipped with a first programmable logic chip (CPLD1), a second programmable logic chip (CPLD2), and a third programmable logic chip (CPLD3). The first programmable logic chip is used to generate six channels of electrical energy pulses. The main control unit reads data from the ADC (analog-to-digital converter) of the acquisition unit through the data bus, performs digital filtering to obtain voltage and current values, and generates corresponding six channels of electrical energy pulses for the calibration of the meter under test. The power supply unit is electrically connected to the main control unit, the six sets of acquisition units, the high-current acquisition unit, the human-machine interface display unit, and the communication unit.

[0034] like Figure 2 As shown, in this embodiment, the main control unit uses a 32-bit ARM high-speed processor with a maximum clock frequency of 200MHz, which can calculate voltage, current, and power values ​​in real time and display the data on the human-machine interface. To reduce the processor load, the main control unit also adds three programmable logic devices (CPLDs). CPLD1 is used to generate 6 channels of power pulses; CPLD2 converts 13 channels of ADC serial data into parallel data, which the processor can quickly read from each group of data; CPLD3 generates a 25.6KHz sampling frequency signal, which the ADC uses to continuously convert data, making the sampling frequency controllable.

[0035] like Figure 3 , Figure 4As shown in this embodiment, the acquisition unit includes an ADC (Analog-to-Digital Converter). The ADC's function is to discretize the analog signal output from the acquisition unit and convert it into a digital signal that a computer can process. Each acquisition unit consists of one high-voltage and one low-voltage input. The high-voltage input uses a precision resistor divider, with a measurement range of 10-1500V. The divided signal is amplified to a suitable amplitude by a programmable operational amplifier (PAP) to improve the ADC's resolution. The low-voltage input is directly fed in, amplified by a differential filter and PAP, and then fed into the ADC for sampling, with a measurement range of 0-10V. The high-voltage and low-voltage sampling are powered by two separate linear power supplies, completely isolated from each other. The ADC sampling data is magnetically isolated from the main control unit, ensuring no interference between units. The high-current acquisition unit uses a DC comparator for sampling, offering fast response, wide measurement frequency, good accuracy with low currents, and a measurement range of 0-1000A. The acquisition unit and the main control unit use a standard defined interface, which includes the power supply for each sampling circuit, serial data bus, programmable operational amplifier control signals, and sampling frequency signals, ensuring correct communication with the main control unit and facilitating subsequent interface function expansion.

[0036] The magnetic isolation of this invention is a magnetic coupling isolation technology.

[0037] In this embodiment, the power supply unit adopts a high-precision DC standard meter with a wide measurement range and high accuracy. In order to ensure the accuracy of the standard meter, the power supply part of the standard meter uses a linear power supply, and the power supply of each unit is completely isolated to prevent interference caused by common ground.

[0038] The HMI display unit uses a high-definition 7-inch capacitive touchscreen to display six channels of measurement information such as voltage, current, and power, as well as some parameter settings.

[0039] This invention proposes a six-channel high-precision DC standard energy meter, capable of simultaneously measuring six high-voltage channels, six low-voltage channels, and one high-current channel. It can simultaneously calibrate six DC meters, significantly improving efficiency. The six-channel DC standard energy meter uses a card-based design, allowing for configuration of 1-6 channel standard meters according to requirements, reducing redundant development costs. Furthermore, the data acquisition card uses a standard interface, enabling expansion to other measurement modes and enhancing the device's scalability.

[0040] The DC standard meter adopts a plug-in card design, integrating each functional module onto a single card, reducing overall wiring and improving reliability. The standard meter can also be configured as a 1-6 channel standard meter, reducing development costs and facilitating the design of the number of channels in the calibration device. Each card connects via a standard defined adapter interface, enabling data exchange, power supply, and other functions. The data acquisition card interface uses a standard bus protocol interface, allowing for the expansion of other acquisition functions such as AC voltage and AC current sampling, improving the device's scalability.

[0041] In this embodiment, after the DC standard meter is powered on, the ARM processor sends data to CPLD3 via the data bus. CPLD3 generates a 25.6kHz sampling frequency signal. Through the standard adapter interface, the 13 ADCs of the 7 acquisition cards receive the sampling frequency signal and begin data conversion. CPLD2 converts the serial data output by the ADC into parallel data and stores it. The ARM processor reads these 13 sets of data, processes them, calculates the power of each channel, and sends data to CPLD1 to generate the corresponding standard power pulse. The ARM processor outputs the measurement data to the display unit.

[0042] The above description is only a preferred embodiment of the present utility model and does not limit the scope of patent protection of the present utility model. Any equivalent structural transformations made based on the content of the present utility model specification and drawings, whether directly or indirectly applied to other related technical fields, are similarly included within the scope of protection of the present utility model.

Claims

1. A six-channel DC standard meter characterized in that, include: The system comprises a main control unit, six acquisition units, a high-current acquisition unit, a human-machine interface display unit, a power supply unit, and a communication unit. The six acquisition units and the high-current acquisition unit are electrically connected to the main control unit via a standard bus interface. Each acquisition unit contains an analog-to-digital converter. The main control unit is electrically connected to the human-machine interface display unit and the communication unit. The main control unit includes a first programmable logic chip, a second programmable logic chip, and a third programmable logic chip. The first programmable logic chip is used for generating six channels of electrical energy pulses. The main control unit reads the ADC data from the acquisition unit through the data bus, performs digital filtering to obtain voltage and current values, and generates corresponding 6-channel power pulses for the calibration of the meter under test.

2. A six-pass direct-current standard meter as claimed in claim 1, characterized in that, The second programmable logic chip is used to convert the 13-channel ADC serial data into parallel data, and the processor can quickly read each group of data.

3. A six-pass direct-current standard meter as defined in claim 1, wherein, The third programmable logic chip is used to generate a 25.6kHz sampling frequency signal, and the ADC converts data based on this signal.

4. A six-pass direct-current standard meter as defined in claim 1, wherein, Each acquisition unit includes one high voltage and one low voltage, with the high voltage using a precision resistor voltage divider.

5. A six-pass direct-current standard meter as claimed in claim 1 or 2 or 3 or 4, characterized in that, The main control unit uses a 32-bit ARM high-speed processor.

6. A six-pass DC standard meter as claimed in claim 5, characterized in that, The maximum clock speed of the 32-bit ARM high-speed processor is 200MHz.

7. A six-pass direct-current standard meter as claimed in claim 1 or 2 or 3 or 4, characterized in that, The human-machine interface display unit uses a high-definition 7-inch capacitive touch screen.

8. A six-pass direct-current standard meter as defined in claim 7, wherein, The human-machine interface display unit is used to display the voltage, current, power, and parameter settings of the six channels.

9. A six-pass direct-current standard meter as claimed in claim 1 or 2 or 3 or 4, characterized in that, The measurement range of the high current acquisition unit is 0-1000A.

10. A six-pass DC standard meter as claimed in claim 5, characterized in that, The 32-bit ARM high-speed processor outputs the measurement data to the human-machine interface display unit.

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