CN112230052A

CN112230052A - Electric energy meter metering core scheme design meeting IR46 requirement

Info

Publication number: CN112230052A
Application number: CN202010765885.XA
Authority: CN
Inventors: 刁瑞朋; 刘承志
Original assignee: Qingdao Topscomm Communication Co Ltd
Current assignee: Qingdao Topscomm Communication Co Ltd
Priority date: 2020-08-03
Filing date: 2020-08-03
Publication date: 2021-01-15

Abstract

The invention provides a design scheme of a metering core of an electric energy meter, which meets the requirements of an IR46 standard. The scheme adopts a modular design, provides a standard interface with a management core and an uplink communication module, and comprises a power supply circuit, an MCU control circuit, a metering circuit, a data storage circuit, a safety certification circuit, an error self-detection circuit and a terminal seat temperature measurement circuit; the system can provide legal data such as electric quantity and clock, and can perform tasks such as event recording and error online monitoring.

Description

Electric energy meter metering core scheme design meeting IR46 requirement

Technical Field

The invention relates to the field of intelligent electric energy meters, and provides a design scheme of an electric energy meter measuring core meeting IR46 requirements, which comprises a power supply circuit, an MCU control circuit, a measuring circuit, a data storage circuit, a safety certification circuit, an error self-detection circuit and a terminal seat temperature measurement circuit, and is specially designed aiming at the standard requirements of International Recommendation 46 active electric energy meter newly formulated by the International legal measuring organization.

Background

The International Recommendation 46 active electric energy meter made by the International legal measurement organization was published in 10 months of 2012. China as a member country must adopt and implement this standard. The electric energy meter required by the current standard system of the electric energy meter in China is designed integrally, software is not allowed to be upgraded after the electric energy meter is hung on the site, and the whole electric energy meter can only be replaced when the requirement is changed or the electric energy meter is in failure. Therefore, it is a trend to develop an electric energy meter conforming to the IR46 standard by applying the IR46 standard.

Disclosure of Invention

The invention aims to provide a metering core scheme design which can meet the requirements of IR46 standards, can take the metering related functions of an IR46 single-phase meter, and can execute tasks such as event recording, pulse output, error online monitoring and the like.

The technical scheme of the invention is as follows: and a modular design is adopted, and a standard interface circuit is provided for the management core, the expansion module and the uplink module. And the metering data is transmitted to the management core through the interface and is responsible for the related functions of the whole meter metering.

Drawings

FIG. 1 is a block diagram of a metering core module of an electric energy meter;

Detailed Description

Referring to fig. 1, the main MCU of the metering core uses an ARM chip of a CK802 core and includes 4 SPI interfaces. The 4 paths of UART interfaces are respectively used for a security authentication module, an internal storage module, an expansion module and a management core communication interface; the circuit is provided with 5 paths of independent ADCs (analog to digital converters) for measuring the temperature of 4 terminal blocks and a clock temperature compensation circuit; the system is provided with 4 paths of UARTs for metering communication and interface output, and 1 path of UARTs is reserved for subsequent function expansion.

Adopt standard interface definition between measurement core and management core and the extension module, add the electrostatic protection circuit between the interface, can satisfy the electrostatic protection demand when guaranteeing communication rate, support the hot plug.

The main power supply of the metering core uses a high-efficiency switching power supply, can convert AC220V into DC16V, converts the voltage into 15V through the LDO to supply power for the management module, and the 5V power supply required by the metering core is provided by the DC-DC module. The power supply device is provided with the battery and the super capacitor energy storage circuit, can provide electric quantity for maintaining normal output of the clock during 220V power-off of the main power supply, ensures accuracy of the clock, is powered by the super capacitor when the battery is replaced, and can maintain the clock to work for at least two days.

The 24-bit high-precision sigma-delta ADC metering chip is used in the metering core, a high-precision high-stability reference voltage circuit can be provided, phase and environment temperature compensation of a signal path can be realized, and high precision of metering data is guaranteed.

The error self-detection circuit can output a current source signal with fixed frequency and fixed amplitude to the sampling circuit, and the signal collected by the sampling circuit is analyzed, so that the active metering error change of the sampling circuit caused by electricity stealing, failure, aging or failure can be realized, and the error self-detection of the sampling circuit is realized.

The uncovering detection circuit can detect and record every uncovering event, and the realization of the function can be maintained through the electric quantity provided by the battery and the energy storage device even if the commercial power is cut off.

The terminal seat temperature measurement circuit calculates the actual temperature of the copper bar by collecting the resistance value change of the thermistor embedded in the copper bar, and can generate alarm information when the temperature of the terminal seat is overheated and the temperature of the terminal seat is unbalanced, so that the power utilization safety is ensured.

The internal storage module uses a large-capacity FLASH circuit to meet the storage requirement of a large amount of data.

The safety certification module uses an ESAM circuit of an object-oriented protocol to meet the requirement of a safety certification function.

Claims

1. The electric energy meter measuring core meeting the IR46 requirement is characterized in that: and a modular design is adopted, and a standard interface for communicating with the management core, the expansion module and the uplink module is provided.

2. An IR46 metering core according to claim 1, wherein: the interface has electrostatic protection capability and supports module hot plug.

3. An IR46 metering core according to claim 1, wherein: the power-off protection device is provided with a battery and an energy storage circuit, and the normal operation of the clock is guaranteed to be maintained under the condition that the mains supply is powered off.

4. An IR46 metering core according to claim 1, wherein: the device is provided with a high-precision current and voltage metering module.

5. An IR46 metering core according to claim 1, wherein: the active metering error change of the current and voltage sampling circuit caused by electricity stealing, failure, aging or failure can be monitored on line.

6. An IR46 metering core according to claim 1, wherein: the cover opening event can be detected under the condition that the mains supply is powered down.

7. An IR46 metering core according to claim 1, wherein: the temperature of the zero live wire terminal copper bar can be measured in real time.

8. An IR46 metering core according to claim 1, wherein: the data storage circuit is provided, and can store a large amount of metering related data.

9. An IR46 metering core according to claim 1, wherein: a security authentication circuit is provided.