CN102565583A - Power quality monitoring terminal for switch-in electronic mutual inductor - Google Patents

Abstract

The invention relates to a power quality monitoring terminal connected to an electronic transformer. Its technical characteristics are: it is composed of an optical fiber transceiver connected to a CPU, and the optical fiber transceiver is connected to the electronic transformer on the process layer through an optical fiber to receive electronic The real-time sampling data output by the transformer is sent to the CPU, and the CPU performs power analysis and calculation on the received real-time sampling data, and uploads the calculated power quality data to the station control layer through the network interface. The invention has a reasonable design, realizes the function of simultaneously monitoring multiple outgoing lines in one monitoring terminal, reduces equipment cost, effectively avoids the influence of electromagnetic interference, and greatly improves stability, reliability, safety, etc. It meets the accuracy required for power quality monitoring and analysis, and adapts to the power quality monitoring requirements of smart grids.

Description

Power quality monitoring terminal connected to electronic transformer

technical field

The invention belongs to the field of smart grids, in particular to a power quality monitoring terminal connected to an electronic transformer. the

Background technique

The smart grid and the traditional grid have undergone great changes in the way of analog quantity acquisition. The analog signal input by the cable from the traditional voltage and current transformer is transformed into the digital signal of the electronic transformer input by the communication cable or optical fiber. The traditional power grid substation, as shown in Figure 2, transmits 100V/5A analog signals to each acquisition device (including protection and power quality monitoring) through cables through electromagnetic voltage and current transformers. Each acquisition device needs to be equipped with voltage and current mutual inductance The device converts the analog signal into a small signal that the embedded device can receive, converts it into a digital signal through AD conversion, and performs correlation calculations by the CPU. Due to the relatively large volume of electromagnetic voltage and current transformers, a single device cannot monitor multiple outgoing lines at the same time, and each analog signal needs to be equipped with a high-precision AD converter, which is costly. Therefore, the power quality monitoring terminal using the traditional grid cannot meet the needs of the smart grid. the

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a power quality monitoring terminal connected to an electronic transformer that can simultaneously monitor multiple outgoing lines and meet the requirements of a smart grid. the

The present invention solves its technical problem and realizes by taking the following technical solutions:

A power quality monitoring terminal connected to an electronic transformer, which is composed of a fiber optic transceiver connected to a CPU. The fiber optic transceiver is connected to the electronic transformer on the process layer through an optical fiber to receive real-time sampling data output by the electronic transformer and send it to The CPU performs power analysis and calculation on the received real-time sampling data, and uploads the calculated power quality data to the station control layer through the network interface. the

Moreover, said CPU is DSP or FPGA. the

Moreover, the real-time sampling data includes voltage and current data of multiple outgoing lines. the

Moreover, the power quality data includes voltage deviation, frequency deviation, harmonics, voltage fluctuation and flicker, and three-phase unbalance data. the

Advantage and positive effect of the present invention are:

The invention adopts the optical fiber transceiver to receive digital real-time sampling data from the electronic transformer, and performs corresponding analysis and processing, which not only simplifies the hardware structure of the monitoring terminal, realizes effective electrical isolation of primary and secondary equipment, but also improves the monitoring terminal Accuracy and reliability, realizing the digital application of data acquisition, avoiding the influence of electromagnetic interference, greatly improving stability, reliability, security, etc., providing accurate and reliable data sources for power quality analysis , which meets the accuracy required for power quality monitoring and analysis. At the same time, since the sampling data packet received by the optical fiber transceiver contains conversion signals for multiple outgoing lines, one monitoring terminal can simultaneously monitor multiple outgoing lines. The cost of equipment is saved. the

Description of drawings

Fig. 1 is a circuit block diagram of the present invention;

Figure 2 is a circuit block diagram of a traditional substation. the

Detailed ways

Embodiment of the present invention is described in further detail below in conjunction with accompanying drawing:

A power quality monitoring terminal connected to an electronic transformer, as shown in Figure 1, is composed of a fiber optic transceiver connected to a CPU. The fiber optic transceiver is connected to the electronic transformer on the process layer through an optical fiber. The fiber optic transceiver receives electronic The real-time sampling data such as voltage and current output by the transformer are sent to the CPU, and the CPU performs power analysis and calculation on the received real-time sampling data such as voltage and current to obtain voltage deviation, frequency deviation, harmonics, voltage fluctuations and flicker, Power quality technical indicators such as three-phase unbalance, and upload the analysis results to the station control layer through the network interface. In this embodiment, the optical fiber transceiver adopts the optical fiber transceiver of AVAGO Company, and the CPU can adopt DSP (Digital Signal Processor) or FPGA (Field Programmable Gate Array) or other microprocessor modules. the

Since the smart substation uses electronic transformers, which output digital signals through optical fibers, the digital signals can be directly received by the power quality monitoring terminal, eliminating the need for conversion from analog to digital, and only need to be carried out according to the relevant protocols of IEC61850 The data signal can be converted, and the CPU can directly perform correlation calculations on the signal to calculate various monitoring indicators of power quality. Since the data packet received by the optical fiber transceiver contains multiple outgoing conversion signals, one CPU can realize simultaneous Monitoring multiple outgoing lines greatly saves the cost of equipment. At the same time, since the power quality monitoring terminal receives optical signals instead of conventional electrical signals, the influence of electromagnetic interference is greatly reduced, thus improving the electromagnetic compatibility level of the entire terminal. the

The working process of the present invention is: the monitoring terminal performs photoelectric conversion on the optical signal transmitted by the process layer electronic transformer through the optical fiber transceiver, analyzes the Internet protocol (TCP/IP), and decodes the received data packet according to the IEC61850 protocol specification , to obtain real-time sampling data of voltage and current, and then conduct power analysis on the sampling data, calculate voltage deviation, frequency deviation, harmonics, voltage fluctuation and flicker, three-phase unbalance and other power quality technical indicators, and upload the analysis results through the network The station control layer realizes the real-time monitoring function of power quality. the

It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive, so the present invention is not limited to the embodiments described in the specific implementation, and those skilled in the art according to the technical solutions of the present invention Other obtained implementation modes also belong to the protection scope of the present invention. the

Claims (4)

1. A power quality monitoring terminal connected to an electronic transformer, characterized in that: it is composed of a fiber optic transceiver connected to a CPU, and the fiber optic transceiver is connected to the electronic transformer of the process layer through an optical fiber to receive the output of the electronic transformer The real-time sampling data is sent to the CPU, and the CPU performs power analysis and calculation on the received real-time sampling data, and uploads the calculated power quality data to the station control layer through the network interface. 2. The power quality monitoring terminal connected to the electronic transformer according to claim 1, characterized in that: said CPU is DSP or FPGA. 3. The power quality monitoring terminal connected to an electronic transformer according to claim 1, wherein the real-time sampling data includes voltage and current data of multiple outgoing lines. 4. The power quality monitoring terminal connected to the electronic transformer according to claim 1, characterized in that: said power quality data includes voltage deviation, frequency deviation, harmonics, voltage fluctuation and flicker, three-phase Balance data.

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