阅读说明：本技术 一种用于监测光纤电流互感器标度因数的系统及方法 (System and method for monitoring scale factor of optical fiber current transformer ) 是由 胡蓓 肖浩 夏历 彭慎 郭浩洲 吴永康 肖梁乐 贺伟 郭子君 唐芳 刘东伟 刘 于 2020-11-24 设计创作，主要内容包括：本发明公开了一种用于监测光纤电流互感器标度因数的系统及方法,属于光纤电流互感器技术领域。本发明方法,包括：驱动模块,所述驱动模块用于驱动光路模块运行；信号处理模块,所述信号处理模块输出电压调制信号,接收光路模块采集的光纤电流互感器的光源中心波长和光功率,根据光源中心波长和光功率确定电流互感器的标度因数；光路模块,所述光路模块运行后,接收电压调制信号,根据电压调制信号对光纤电流互感器进行在线监测,采集光纤电流互感器的光源中心波长和光功率。本发明实现了光纤电流互感器光源中心波长和输出光功率的在线监测功能,并消除了光源光功率衰减对光纤电流互感器测量的不稳定性影响,提高互感器长期运行可靠性。(The invention discloses a system and a method for monitoring scale factors of an optical fiber current transformer, and belongs to the technical field of optical fiber current transformers. The method comprises the following steps: the driving module is used for driving the light path module to operate; the signal processing module outputs a voltage modulation signal, receives the light source central wavelength and the light power of the optical fiber current transformer collected by the light path module, and determines the scale factor of the current transformer according to the light source central wavelength and the light power; and the light path module receives the voltage modulation signal after running, carries out online monitoring on the optical fiber current transformer according to the voltage modulation signal, and collects the light source center wavelength and the light power of the optical fiber current transformer. The invention realizes the function of monitoring the central wavelength and the output optical power of the optical fiber current transformer on line, eliminates the unstable influence of the optical power attenuation of the light source on the measurement of the optical fiber current transformer and improves the long-term operation reliability of the transformer.)

1. A system for monitoring a fiber optic current transformer scale factor, the system comprising:

the driving module is used for driving the light path module to operate;

the signal processing module outputs a voltage modulation signal, receives the light source central wavelength and the light power of the optical fiber current transformer collected by the light path module, and determines the scale factor of the current transformer according to the light source central wavelength and the light power;

and the light path module receives the voltage modulation signal after running, carries out online monitoring on the optical fiber current transformer according to the voltage modulation signal, and collects the light source center wavelength and the light power of the optical fiber current transformer.

2. The system of claim 1, further comprising a power module that provides power to the system.

3. The system of claim 1, further comprising: and the upper computer module receives the light source central wavelength and the optical power determined by the signal processing module and carries out online monitoring on the light source central wavelength and the optical power.

4. The system of claim 1, the optical path module, comprising:

the broadband light source generates and emits optical signals;

the coupler divides an optical signal emitted by the broadband light source into two paths of optical signals to be output;

the polarizer receives a path of optical signal generated linear polarized light emitted by the coupler;

a phase modulator that receives and modulates the line polarization light;

the delay ring transmits the modulated linearly polarized light in a delayed manner and outputs two beams of linearly polarized light which are perpendicular to each other;

the wave plate receives two beams of linearly polarized light which are perpendicular to each other, one beam of the two beams of linearly polarized light which are perpendicular to each other is converted into left-handed polarized light, and the other beam of the two beams of linearly polarized light is converted into right-handed polarized light;

the optical fiber sensing ring and the optical fiber sensor receive left-handed polarized light and right-handed polarized light, and interference light signals in opposite directions generated by the left-handed polarized light and the right-handed polarized light under the action of current are returned to the main detector;

the wavelength division multiplexer receives one path of optical signal output by the coupler, splits the optical signal and transmits the optical signal to the state detector;

the state detector receives the optical signal split by the wavelength division multiplexer, converts the optical signal into an electric signal and collects the electric signal by the signal processing module;

and the main detector receives the interference optical signal of the optical fiber sensing ring, converts the interference optical signal into a voltage signal and determines the optical power according to the voltage signal.

5. The system of claim 4, wherein the status detector comprises a plurality of status detectors, and the number of status detectors corresponds to the number of optical signal splits split by the wavelength division multiplexer.

6. The system of claim 4, the coupler being a 2 x 2 coupler.

7. The system of claim 4, the voltage modulation signal comprising: square and sawtooth voltage modulation signals.

8. A method for monitoring a fiber optic current transformer scale factor, the method comprising:

controlling the driving module to drive the light path module to operate;

controlling the signal processing module to output a voltage modulation signal;

the control light path module receives the voltage modulation signal, carries out on-line monitoring on the optical fiber current transformer according to the voltage modulation signal, collects the output voltage signal of the state detector, carries out data fitting according to the distribution rule of the collected voltage signal, and calculates the light source center wavelength and the light power of the optical fiber current transformer

And the control signal processing module determines the scale factor of the current transformer according to the central wavelength and the optical power of the light source.

9. The method of claim 8, the voltage modulation signal comprising: square and sawtooth voltage modulation signals.

Technical Field

The present invention relates to the field of fiber optic current transformers, and more particularly, to a system and method for monitoring a scale factor of a fiber optic current transformer.

Background

The fundamental principle of an Optical Fiber Current Transformer (FOCT) is based on the Faraday magneto-Optical effect, belongs to an electronic Current Transformer, and the output result of the FOCT is used as an important data source for monitoring and judging the operating state of a power system. According to the national standard of the electronic current transformer, a ratio error (ratio difference) and a phase error (phase difference) are two important indexes for evaluating the accuracy of FOCT measurement. The scaling factor is the ratio of FOCT output to input, and the stability of the FOCT is the most important index for representing the measurement accuracy of the transformer.

During long-term operation of an FOCT, the optical power of the light source is continuously attenuated due to the inherent properties of the semiconductor light source, and the attenuation is accompanied by a shift in the center wavelength, which is a main cause of the change of the FOCT scale factor during long-term operation.

The main object of state monitoring in the existing FOCT is optical power of an optical path, a path of photoelectric detector can be added at the monitoring end of a coupler at the rear stage of a light source, or the judgment can be carried out by directly returning the optical power of a main detector of a system in the FOCT optical path, but no existing scheme exists for monitoring the central wavelength of the light source in the FOCT.

Disclosure of Invention

In view of the above problem, the present invention provides a system for monitoring a scale factor of a fiber optic current transformer, comprising:

the driving module is used for driving the light path module to operate;

the signal processing module outputs a voltage modulation signal, calculates the light source central wavelength and the optical power of the optical fiber current transformer according to the output voltage signal of the state detector, and determines the scale factor of the current transformer according to the light source central wavelength and the optical power;

and the light path module receives the voltage modulation signal after running and carries out online monitoring on the optical fiber current transformer according to the voltage modulation signal.

Optionally, the system further includes a power module, and the power module provides power for the system.

Optionally, the system further comprises: and the upper computer module receives the light source central wavelength and the optical power determined by the signal processing module and carries out online monitoring on the light source central wavelength and the optical power.

Optionally, the optical path module includes:

the broadband light source generates and emits optical signals;

the coupler divides an optical signal emitted by the broadband light source into two paths of optical signals to be output;

the polarizer receives a path of optical signal generated linear polarized light emitted by the coupler;

a phase modulator that receives and modulates the line polarization light;

the delay ring transmits the modulated linearly polarized light in a delayed manner and outputs two beams of linearly polarized light which are perpendicular to each other;

the wave plate receives two beams of linearly polarized light which are perpendicular to each other, one beam of the two beams of linearly polarized light which are perpendicular to each other is converted into left-handed polarized light, and the other beam of the two beams of linearly polarized light is converted into right-handed polarized light;

the optical fiber sensing ring and the optical fiber sensor receive left-handed polarized light and right-handed polarized light, and interference light signals in opposite directions generated by the left-handed polarized light and the right-handed polarized light under the action of current are returned to the main detector;

the wavelength division multiplexer receives one path of optical signal output by the coupler, splits the optical signal and transmits the optical signal to the state detector;

the state detector receives the optical signal split by the wavelength division multiplexer, converts the optical signal into an electric signal and collects the electric signal by the signal processing module;

and the main detector receives the interference optical signal of the optical fiber sensing ring, converts the interference optical signal into a voltage signal and determines the optical power according to the voltage signal.

Optionally, the number of the state detectors is equal to the number of the optical signals split by the wavelength division multiplexer.

Optionally, the coupler is a 2 × 2 coupler.

Optionally, the voltage modulation signal includes: square and sawtooth voltage modulation signals.

The invention also provides a method for monitoring the scale factor of the optical fiber current transformer, which comprises the following steps:

controlling the driving module to drive the light path module to operate;

controlling the signal processing module to output a voltage modulation signal;

the control light path module receives the voltage modulation signal, carries out online monitoring on the optical fiber current transformer according to the voltage modulation signal, and collects the light source center wavelength and the light power of the optical fiber current transformer;

the control signal processing module is used for acquiring the output voltage signal of the state detector, performing data fitting according to the distribution rule of the acquired voltage signal, calculating the light source central wavelength and the optical power of the optical fiber current transformer, and determining the scale factor of the current transformer according to the light source central wavelength and the optical power;

optionally, the voltage modulation signal includes: square and sawtooth voltage modulation signals.

The invention realizes the function of monitoring the central wavelength and the output optical power of the optical fiber current transformer on line, eliminates the unstable influence of the optical power attenuation of the light source on the measurement of the optical fiber current transformer and improves the long-term operation reliability of the transformer.

Drawings

FIG. 1 is a block diagram of a system for monitoring the scale factor of a fiber optic current transformer in accordance with the present invention;

FIG. 2 is a block diagram of an optical path module of a system for monitoring scale factors of a fiber optic current transformer of the present invention;

FIG. 3 is a graph of center wavelength and optical power versus time for a system for monitoring the scale factor of a fiber optic current transformer in accordance with the present invention;

FIG. 4 is a flow chart of a method for monitoring the scale factor of a fiber optic current transformer in accordance with the present invention.

Detailed Description

The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, however, the present invention may be embodied in many different forms and is not limited to the embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, the same units/elements are denoted by the same reference numerals.

Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.

The invention provides a system for monitoring a scale factor of a fiber-optic current transformer, as shown in fig. 1, comprising:

the driving module is used for driving the light path module to operate;

the signal processing module outputs a voltage modulation signal, collects the output voltage signal of the state detector, performs data fitting according to the distribution rule of the collected voltage signal, calculates the light source central wavelength and the light power of the optical fiber current transformer, and determines the scale factor of the current transformer according to the light source central wavelength and the light power;

and the light path module receives the voltage modulation signal after running and carries out online monitoring on the optical fiber current transformer according to the voltage modulation signal.

And the power supply module provides power for the system.

And the upper computer module receives the light source central wavelength and the optical power determined by the signal processing module and carries out online monitoring on the light source central wavelength and the optical power.

The optical path module, as shown in fig. 2, includes:

the broadband light source generates and emits optical signals;

the coupler divides an optical signal emitted by the broadband light source into two paths of optical signals to be output;

the polarizer receives a path of optical signal generated linear polarized light emitted by the coupler;

a phase modulator that receives and modulates the line polarization light;

the delay ring transmits the modulated linearly polarized light in a delayed manner and outputs two beams of linearly polarized light which are perpendicular to each other;

the wave plate receives two beams of linearly polarized light which are perpendicular to each other, one beam of the two beams of linearly polarized light which are perpendicular to each other is converted into left-handed polarized light, and the other beam of the two beams of linearly polarized light is converted into right-handed polarized light;

the optical fiber sensing ring and the optical fiber sensor receive left-handed polarized light and right-handed polarized light, and interference light signals in opposite directions generated by the left-handed polarized light and the right-handed polarized light under the action of current are returned to the main detector;

the wavelength division multiplexer receives one path of optical signal output by the coupler, splits the optical signal and transmits the optical signal to the state detector;

the state detector receives the optical signal split by the wavelength division multiplexer, converts the optical signal into an electric signal and collects the electric signal by the signal processing module;

and the main detector receives the interference optical signal of the optical fiber sensing ring, converts the interference optical signal into a voltage signal and determines the optical power according to the voltage signal.

The method comprises the following specific steps:

as shown in fig. 2, in the optical path module, light emitted by the broadband light source is divided into two paths after passing through the 2 × 2 coupler;

1/2 light beam output from one port of the coupler is processed by a polarizer to form linear polarized light, the linear polarized light is orthogonally decomposed into two beams of mutually perpendicular linear polarized light by 45-degree welding, the two beams of mutually perpendicular linear polarized light are respectively injected into a fast axis and a slow axis of the polarization-maintaining optical fiber for transmission, and the two beams of mutually perpendicular linear polarized light are transmitted through the modulation effect of the phase modulator and the transmission of the delay optical fiber, two beams of mutually vertical linearly polarized light enter 1/4 wave plates to form a left polarized light and a right polarized light which enter a sensing optical fiber ring, two beams of circularly polarized light generate phase shifts in opposite directions under the action of current and return to a main detector, interference optical signals caused by the current in an optical path are converted into analog electric signals, the analog electric signal is filtered by a signal processing system module II and is subjected to A/D conversion after passing through a preamplifier to realize the demodulation of a digital signal, so that the detection and the output of a current signal are realized, and the current signal is output to an upper computer for displaying through a corresponding communication protocol;

1/2 light beams output by the second coupler port enter the state detector 1, the state detector 2, … … and the state detector k through the light beams obtained after the light beams are split by the wavelength division multiplexer, because a light source device of the optical fiber current transformer usually adopts a wide-spectrum light source, the wavelength division multiplexer divides the light power of the monitoring end of the coupler into k beams, and the k beams of light signals can be regarded as the frequency spectrum division of the wide-spectrum light signals, the sum of the power of the 1-k beams of light signals reflects the light power of the monitoring end of the coupler, and the power distribution of the 1-k beams of light signals can reflect the central wavelength of the light signals output by the coupler end.

As shown in FIG. 3, assuming that the sequence of optical powers detected by the state detector is P [ k ], then Σ P [ k ] can be used to characterize the change in output optical power of the light source, and the sequence of ratios of the powers in P [ k ] compared to some initial value can be used to estimate the center wavelength. The long-term on-line monitoring of the light power and the central wavelength of the light source can be realized by monitoring the light power of all the state detectors, and the self-diagnosis analysis is further carried out by utilizing the monitoring result.

The state detectors 1-k obtain the light power attenuation amplitude of the SLD light source through the signal processing and collecting unit, obtain the scale factor change amplitude caused by light power change according to the pre-fitting function, apply the change coefficient to the signal processing unit of the main detector, correct the scale factor of the optical fiber current transformer, and take the corrected result as the final output of the transformer, thereby realizing the online monitoring and correction of the scale factor in the long-term operation process.

The number of the state detectors is consistent with the number of the light signals split by the wavelength division multiplexer.

The coupler is a 2 x 2 coupler.

The voltage modulation signal includes: square and sawtooth voltage modulation signals.

The invention also provides a method for monitoring the scale factor of the optical fiber current transformer, as shown in fig. 4, comprising the following steps:

controlling the driving module to drive the light path module to operate;

the control signal processing module outputs a voltage modulation signal,

the control light path module receives the voltage modulation signal, carries out on-line monitoring on the optical fiber current transformer according to the voltage modulation signal, and collects the light source center wavelength and the light power of the optical fiber current transformer

The control signal processing module is used for receiving the light source central wavelength and the light power of the optical fiber current transformer collected by the light path module and determining the scale factor of the current transformer according to the light source central wavelength and the light power;

the voltage modulation signal includes: square and sawtooth voltage modulation signals.

The invention realizes the on-line monitoring and self-diagnosis of the central wavelength and the output optical power of the light source of the optical fiber current transformer, realizes the on-line monitoring and self-correction of the scale factor according to the self-diagnosis test result, eliminates the unstable influence of the light power attenuation of the light source on the measurement of the optical fiber current transformer, and improves the long-term operation reliability of the transformer.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein. The scheme in the embodiment of the application can be implemented by adopting various computer languages, such as object-oriented programming language Java and transliterated scripting language JavaScript.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.