Switching System Based on Measurement Channels of a Metering Chip and Its Phase Sequence Adjustment Method

Abstract

A switching system based on a measurement channel of a metering chip and its phase sequence adjustment method according to the present invention includes an MCU unit, a metering chip unit, a voltage sampling unit, a current sampling unit, and a phase sequence adjustment unit; the MCU unit and the metering chip unit perform data communication in an SPI manner; the MCU unit is also connected to the phase sequence adjustment unit, and the phase sequence adjustment unit performs corresponding phase sequence adjustment according to a phase sequence adjustment command from the MCU unit; the phase sequence adjustment unit and the current sampling unit are connected to the metering chip unit; the voltage sampling unit is connected to the phase sequence adjustment unit, and the voltage sampling unit converts the grid strong electrical signal into a voltage signal within the sampling range of the metering chip unit and accesses the phase sequence adjustment unit. The present invention achieves the purpose of phase sequence adjustment by physically switching the channels through the designed sampling channel switching circuit on the premise of ensuring high-precision measurement of the metering chip.

Description

Technical Field

[0001] The present invention relates to the technical field of metering chips, and particularly relates to a switching system for measurement channels of a metering chip and a phase sequence adjustment method therefor. Background Art

[0002] With the rapid development of the semiconductor chip industry, traditional mechanical electric energy meters have been gradually replaced by electronic electric energy meters equipped with dedicated metering chips. Meters using dedicated metering chips are favored by the power supply and distribution industries of various industries due to their high accuracy and high reliability. However, each sampling channel of the metering chip must be connected to a fixed power grid phase sequence to ensure the accuracy of measurement (the uniqueness of wiring, and the metering chip itself cannot achieve channel switching). If the phase sequence is connected incorrectly (voltage or current channel), physical wiring adjustment must be carried out after power outage to achieve accurate measurement.

[0003] This requires high requirements for on-site wiring by users. And in the case where wiring errors have already occurred, power outage to adjust the line will affect enterprise production, and power outage in public places will affect production and life; even in some special occasions, the equipment operation cannot be powered off to adjust the wiring, and it is extremely dangerous for workers to operate with electricity. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above deficiencies, and provide a switching system for measurement channels of a metering chip and a phase sequence adjustment method therefor. On the premise of ensuring high-precision measurement of the metering chip, physical switching of channels is achieved through a designed sampling channel switching circuit to achieve the purpose of phase sequence adjustment.

[0005] The purpose of the present invention is achieved as follows:

[0006] A switching system for measurement channels of a metering chip, which includes an MCU unit, a metering chip unit, a voltage sampling unit, a current sampling unit, and a phase sequence adjustment unit; the MCU unit and the metering chip unit perform data communication in an SPI manner; the MCU unit is further connected to the phase sequence adjustment unit, and the phase sequence adjustment unit performs corresponding phase sequence adjustment according to the phase sequence adjustment command from the MCU unit; the phase sequence adjustment unit and the current sampling unit are connected to the metering chip unit, and the current sampling unit converts a large grid current signal or a secondary signal of a power transformer into a voltage signal within the sampling range of the metering chip unit; the voltage sampling unit is connected to the phase sequence adjustment unit, and the voltage sampling unit converts a grid high-voltage signal into a voltage signal within the sampling range of the metering chip unit and accesses the phase sequence adjustment unit.

[0007] Further, the phase sequence adjustment unit includes three independent analog switch channels: a first switch, a second switch, and a third switch, and the three switches are independently controlled by the MCU unit.

[0008] Further, the three-way voltage sampling signals of the voltage sampling unit: the first sampling channel, the second sampling channel, and the third sampling channel are respectively connected in parallel to the three analog switch channels of the phase sequence adjustment unit.

[0009] Further, a zero signal channel is provided for the switching input between the voltage sampling signal and the analog switch channel as an intermediate channel for switching.

[0010] A phase sequence adjustment method for a switching system based on a measurement channel of a metering chip, which includes a phase sequence adjustment unit. The phase sequence adjustment unit is connected between the voltage sampling unit and the metering chip unit and is connected to the MCU unit. The phase sequence adjustment unit includes three analog switch channels: the first switch, the second switch, and the third switch. The three switches are independently controlled by the MCU unit. The first switch is connected to the UA voltage communication signal, and the UA voltage communication signal remains in the same phase as the IA channel of the metering chip. The second switch is connected to the UB voltage communication signal, and the UB voltage communication signal remains in the same phase as the IB channel of the metering chip. The third switch is connected to the UC voltage communication signal, and the UC voltage communication signal remains in the same phase as the IC channel of the metering chip. The three-way voltage sampling signals of the voltage sampling unit: the first sampling channel, the second sampling channel, and the third sampling channel are respectively connected in parallel to the three independent analog switch channels of the phase sequence adjustment unit.

[0011] Further, a zero signal channel is provided for the switching input between the voltage sampling signal and the analog switch channel as an intermediate channel for switching.

[0012] Further, the three analog switch channels of the phase sequence adjustment unit are all implemented by using a single-pole double-throw analog switch 74HC4052.

[0013] Compared with the prior art, the beneficial effects of the present invention are:

[0014] (1) On the premise of ensuring the high-precision measurement of the metering chip, the present invention realizes the physical switching of the channels through the designed sampling channel switching circuit to achieve the purpose of phase sequence adjustment; it solves the problem that the existing metering chip technology cannot realize the switching of the measurement sampling channels.

[0015] (2) The switching of the measurement channels of the present invention is controlled digitally by the MCU and does not use mechanical switches, eliminating the need for on-site operation by personnel and making remote operation safer. The intelligent adjustment of the phase sequence wiring can be realized by using the control software of the corresponding product, reducing manual labor, saving costs, and reducing the professionalism of product installation.

[0016] (3) A switching intermediate channel (zero signal channel) is provided in the switching circuit of the present invention to prevent signal conflicts during the channel switching process and cause abnormal chip measurement. Description of the Drawings

[0017] Figure 1 It is a schematic structural diagram of the switching system of the present invention.

[0018] Figure 2 It is a schematic principle diagram of the phase sequence adjustment unit of the present invention.

[0019] Figure 3 It is a circuit schematic diagram of the phase sequence adjustment circuit of the present invention.

[0020] Wherein:

[0021] MCU unit 1, metering chip unit 2, voltage sampling unit 3, current sampling unit 4, phase sequence adjustment unit 5. Specific implementation mode

[0022] To better understand the technical solution of the present invention, the following will be described in detail in conjunction with relevant drawings. It should be understood that the following specific embodiments are not used to limit the specific implementation forms of the technical solution of the present invention, and they are only the implementation forms that the technical solution of the present invention can adopt. It should be noted first that the expressions about the positional relationships of the components herein, such as component A is located above component B, are based on the relative positions of the components in the drawings and are not used to limit the actual positional relationships of the components.

[0023] Embodiment 1:

[0024] See Figures 1-3 , Figure 1 , a schematic structural diagram of the switching system of the present invention is drawn. As shown in the figure, a switching system based on the measurement channels of a metering chip according to the present invention includes an MCU unit 1, a metering chip unit 2, a voltage sampling unit 3, a current sampling unit 4, and a phase sequence adjustment unit 5.

[0025] The MCU unit 1 and the metering chip unit 2 perform data communication in an SPI manner.

[0026] The MCU unit 1 is also connected to the phase sequence adjustment unit 5, and the phase sequence adjustment unit 5 performs corresponding phase sequence adjustment according to the phase sequence adjustment command from the MCU unit 1.

[0027] The phase sequence adjustment unit 5 and the current sampling unit 4 are connected to the metering chip unit 2, and the current sampling unit 4 converts a large grid current signal or a secondary signal of a power transformer into a voltage signal within the sampling range of the metering chip unit 2.

[0028] The voltage sampling unit 3 is connected to the phase sequence adjustment unit 5, and the voltage sampling unit 3 converts a strong grid power signal into a voltage signal within the sampling range of the metering chip unit 1 and accesses the phase sequence adjustment unit 5.

[0029] See Figure 2 , Figure 2The schematic diagram of the principle of the phase sequence adjustment unit of the present invention is drawn. As shown in the figure, a phase sequence adjustment method for a switching system based on a measurement channel of a metering chip according to the present invention includes a phase sequence adjustment unit 5, and the phase sequence adjustment unit 5 is connected between a voltage sampling unit 3 and a metering chip unit 2 and is connected to an MCU unit 1.

[0030] The phase sequence adjustment unit 5 includes three analog switch channels: a first switch, a second switch, and a third switch. The three switches are independently controlled by the MCU unit 1. The first switch is connected to the UA voltage communication signal, and the UA voltage communication signal remains in phase with the IA channel of the metering chip; the second switch is connected to the UB voltage communication signal, and the UB voltage communication signal remains in phase with the IB channel of the metering chip; the third switch is connected to the UC voltage communication signal, and the UC voltage communication signal remains in phase with the IC channel of the metering chip.

[0031] The three voltage sampling signals of the voltage sampling unit 3: a first sampling channel, a second sampling channel, and a third sampling channel are respectively connected in parallel to the three independent analog switch channels of the phase sequence adjustment unit 5.

[0032] A zero signal channel is set for the switching input between the voltage sampling signal and the analog switch channel as an intermediate channel for switching to prevent signal conflicts of the three voltage sampling signals during the switching process, which may cause abnormalities in the metering chip and affect data judgment.

[0033] The three analog switch channels of the phase sequence adjustment unit 5 are all implemented by using a single-pole double-throw analog switch 74HC4052.

[0034] The present invention achieves the purpose of adjusting the measurement phase sequence of the metering chip by switching the voltage channel. Equivalently, using this invention can derive a fixed voltage channel and achieve phase sequence adjustment by switching the current channel.

[0035] The above is only a specific application example of the present invention and does not constitute any limitation to the protection scope of the present invention. Any technical solution formed by equivalent transformation or equivalent substitution falls within the scope of the protection of the present invention.

Claims

1. A switching system based on the measurement channels of a metering chip, characterized in that: It includes an MCU unit, a metering chip unit, a voltage sampling unit, a current sampling unit, and a phase sequence adjustment unit; the MCU unit and the metering chip unit perform data communication in an SPI manner; the MCU unit is also connected to the phase sequence adjustment unit, and the phase sequence adjustment unit performs corresponding phase sequence adjustment according to the phase sequence adjustment command from the MCU unit; the phase sequence adjustment unit and the current sampling unit are connected to the metering chip unit, and the current sampling unit converts a large grid current signal or a secondary signal of a power transformer into a voltage signal within the sampling range of the metering chip unit; the voltage sampling unit is connected to the phase sequence adjustment unit, and the voltage sampling unit converts a strong grid power signal into a voltage signal within the sampling range of the metering chip unit and accesses the phase sequence adjustment unit. The phase sequence adjustment unit includes three independent analog switch channels: a first switch, a second switch, and a third switch, and the three switches are independently controlled by the MCU unit; three voltage sampling signals of the voltage sampling unit: a first sampling channel, a second sampling channel, and a third sampling channel are respectively connected in parallel to the three analog switch channels of the phase sequence adjustment unit; a zero signal channel is set for the switching input between the voltage sampling signal and the analog switch channel as an intermediate channel for switching.

2. A phase sequence adjustment method for a switching system of a measurement channel based on a metering chip according to claim 1, characterized in that: It includes a phase sequence adjustment unit, the phase sequence adjustment unit is connected between the voltage sampling unit and the metering chip unit and accesses the MCU unit; the phase sequence adjustment unit includes three analog switch channels: a first switch, a second switch, and a third switch, the three switches are independently controlled by the MCU unit, the first switch is connected to the UA voltage communication signal, and the UA voltage communication signal remains in phase with the IA channel of the metering chip; the second switch is connected to the UB voltage communication signal, and the UB voltage communication signal remains in phase with the IB channel of the metering chip; the third switch is connected to the UC voltage communication signal, and the UC voltage communication signal remains in phase with the IC channel of the metering chip; three voltage sampling signals of the voltage sampling unit: a first sampling channel, a second sampling channel, and a third sampling channel are respectively connected in parallel to the three independent analog switch channels of the phase sequence adjustment unit.

3. The phase sequence adjustment method of a switching system based on a measurement channel of a metering chip according to claim 2, characterized in that: A zero signal channel is set for the switching input between the voltage sampling signal and the analog switch channel as an intermediate channel for switching.

4. The phase sequence adjustment method of a switching system based on a measurement channel of a metering chip according to claim 2, wherein: The three analog switch channels of the phase sequence adjustment unit are all implemented using a single-pole double-throw analog switch 74HC4052.

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