CN203178369U - Bushing monitoring system for intelligent substation - Google Patents

Abstract

The utility model relates to a bushing monitoring system for an intelligent substation; the system comprises electronic current transformers measuring a bushing bleeder circuit; signal output of the electronic current transformers is connected with a locally mounted current collector used for completing current signal conditioning, AD conversion and electric light conversion; the current collector is connected with a combiner through a fiber; the combiner is also in sampling connection with bus voltage transformers; and the combiner is connected with a bushing monitoring device through a fiber. The scheme is suitable for the intelligent substation provided with various electronic transformers, so monitoring functions for bushings insulation parameters like dielectric loss factor and equivalence capacitance of power transformers and reactors are completed.

Description

Bushing Monitoring System for Smart Substations

technical field

The utility model relates to a bushing monitoring system suitable for an intelligent substation. the

Background technique

Capacitive equipment is equipped with bushing monitoring devices to monitor insulation parameters such as leakage current, dielectric loss factor and equivalent capacitance of power transformers, reactors and other equipment bushings, and to judge the insulation status of the tested bushings. Faults are predicted to ensure reliable operation of the bushing. the

At present, the harmonic analysis method is mainly used for bushing monitoring. Figure 1 shows a typical wiring diagram of a traditional bushing monitoring solution. It uses current sensors and conventional PTs to collect current and voltage signals, and sends the signals to the In the bushing monitoring device, a series of algorithms are finally used to obtain insulation parameters such as leakage current, so as to judge the insulation state of the bushing. The disadvantages of this method are:

1) It cannot be used in the application of unconventional electronic transformers, and has great limitations;

2) The anti-interference ability of small signal long-distance transmission or 485 communication is poorer than that of optical fiber communication.

Utility model content

The purpose of the utility model is to provide a bushing monitoring system suitable for intelligent substations to solve the problem that the prior art is not suitable for unconventional transformers. the

In order to achieve the above purpose, the solution of this utility model is: a bushing monitoring system suitable for intelligent substations, including an electronic current transformer for measuring the leakage circuit of the bushing, and the signal output of the electronic current transformer is connected to an on-site installation A current collector used to complete current signal conditioning, AD conversion, and electro-optical conversion. The current collector is connected to a combiner through an optical fiber; the combiner is also connected to the bus voltage transformer for sampling, and the combiner is connected to the bushing monitoring device through an optical fiber . the

The bus voltage transformer is an electronic voltage transformer, and the combiner is connected to the electronic voltage transformer through an optical fiber. the

The busbar voltage transformer is an electromagnetic voltage transformer, and the signal output of the electromagnetic voltage transformer is connected to a voltage collector installed on site to complete voltage signal conditioning, AD conversion and electro-optic conversion. the

The scheme of the utility model is suitable for intelligent substations equipped with various electronic transformers, and completes the monitoring function of insulation parameters such as dielectric loss factor and equivalent capacitance of bushings of power transformers and reactors. The monitoring parameters are output in the form of IEC61850. The measurement accuracy of casing monitoring parameters is improved, and the accuracy of insulation parameters is improved. Using optical fiber communication, strong anti-interference ability. the

Description of drawings

Fig. 1 is a system diagram of prior art;

Fig. 2 is the system diagram of embodiment 1;

Fig. 3 is a system diagram of Embodiment 2.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described in further detail. the

Example 1

The structure diagram of the bushing monitoring scheme suitable for electronic transformers is shown in Figure 2. The electronic PT collects the voltage information of the three phases of the high-voltage bus and sends it to the combiner; at the same time, the leakage current of the capacitive bushing passes through the core coil sensor After the signal conditioning and AD conversion are completed, the current collector sent to the bushing is sent to the combiner through the optical fiber in the form of FT3. After the combiner completes synchronous sampling, the signal is sent to the bushing monitoring device through the optical fiber in a 9-2 manner. In this process, the monitoring function of insulation parameters such as dielectric loss factor and equivalent capacitance of bushings of power transformers and reactors is completed.

Example 2

The structure diagram of the bushing monitoring scheme suitable for conventional transformers is shown in Figure 3. When a conventional PT is used, a Hall-principle voltage sensor is installed on the PT cabinet to collect the analog voltage signal of the PT secondary circuit, and its output is sent to To the voltage collector installed locally in the PT cabinet, after completing signal conditioning and AD conversion, it is sent to the combiner in the form of FT3 through optical fiber; at the same time, the leakage current of the capacitive bushing is sent to the bushing through the core coil sensor for local installation After completing signal conditioning and AD conversion, the current collector of the current collector sends it to the same combiner in the form of FT3 through the optical fiber. After the combiner completes synchronous sampling, the signal is sent to the bushing monitoring device through the optical fiber in a 9-2 manner to complete the power transformer, The monitoring function of insulation parameters such as dielectric loss factor and equivalent capacitance of reactor and other equipment bushings.

The above two schemes both make full use of existing process layer equipment, such as electronic transformer collectors, combiners, bushing monitoring devices, etc. are all existing equipment, and use them to realize synchronous collection of casing monitoring data without developing new ones. The advanced hardware equipment has high practicability and economy. the

Claims (3)

1. The bushing monitoring system suitable for intelligent substations is characterized in that it includes an electronic current transformer for measuring the leakage circuit of the bushing, and the signal output of the electronic current transformer is connected to a locally installed, used to complete the current transformer. A current collector for signal conditioning, AD conversion, and electro-optical conversion, the current collector is connected to a combiner through an optical fiber; the combiner is also connected to a bus voltage transformer for sampling, and the combiner is connected to a bushing monitoring device through an optical fiber. 2. The bushing monitoring system suitable for smart substations according to claim 1, wherein the busbar voltage transformer is an electronic voltage transformer, and the combiner is connected to the electronic voltage transformer through an optical fiber. 3. The bushing monitoring system suitable for intelligent substations according to claim 1, wherein the bus voltage transformer is an electromagnetic voltage transformer, and the signal output of the electromagnetic voltage transformer is connected to an on-site installed, A voltage collector used to complete voltage signal conditioning, AD conversion and electro-optical conversion.

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