阅读说明：本技术 一种辅助电源支撑电容监测方法及系统 (Auxiliary power supply support capacitance monitoring method and system ) 是由 李智国 周平宇 杨盼奎 孙卫平 万国强 史小利 梁爽 武继将 于 2021-05-10 设计创作，主要内容包括：本发明提供了一种辅助电源支撑电容监测方法及系统,包括：测量支撑电容介质损耗正切值和电容值；基于测量的支撑电容介质损耗正切值和电容值计算支撑电容容值变化率的修正因子；测量支撑电容的绝缘电阻；基于测量支撑电容的绝缘电阻及测量的支撑电容介质损耗正切值和电容值计算支撑电容绝缘失效因子；基于支撑电容绝缘失效因子及支撑电容容值变化率的修正因子监测辅助电源支撑电容剩余寿命。本发明避免了现场工作人员对动车组辅助电源装置支撑电容拆解安装,可在较短时间内且不破坏支撑电容内部绝缘的情况下便捷、准确、安全地对动车组辅助电源装置支撑电容剩余寿命进行评估。(The invention provides a method and a system for monitoring support capacitance of an auxiliary power supply, which comprises the following steps: measuring the dielectric loss tangent value and the capacitance value of the support capacitor; calculating a correction factor of the capacitance value change rate of the support capacitor based on the measured dielectric loss tangent value and the capacitance value of the support capacitor; measuring the insulation resistance of the support capacitor; calculating an insulation failure factor of the support capacitor based on the insulation resistance of the support capacitor, the measured dielectric loss tangent value and the measured capacitance value of the support capacitor; and monitoring the residual service life of the support capacitor of the auxiliary power supply based on the insulation failure factor of the support capacitor and the correction factor of the capacitance value change rate of the support capacitor. The method avoids the disassembly and the assembly of field workers on the supporting capacitor of the auxiliary power supply device of the motor train unit, and can conveniently, accurately and safely evaluate the residual life of the supporting capacitor of the auxiliary power supply device of the motor train unit in a short time without damaging the internal insulation of the supporting capacitor.)

1. A method for monitoring supporting capacitance of an auxiliary power supply is characterized by comprising the following steps:

measuring the dielectric loss tangent value and the capacitance value of the support capacitor;

calculating a correction factor of the capacitance value change rate of the support capacitor based on the measured dielectric loss tangent value and the capacitance value of the support capacitor;

measuring the insulation resistance of the support capacitor;

calculating an insulation failure factor of the support capacitor based on the insulation resistance of the support capacitor, the measured dielectric loss tangent value and the measured capacitance value of the support capacitor;

and monitoring the residual service life of the support capacitor of the auxiliary power supply based on the insulation failure factor of the support capacitor and the correction factor of the capacitance value change rate of the support capacitor.

2. The method as claimed in claim 1, wherein the method comprises obtaining the dielectric loss tangent, the capacitance and the insulation resistance of the support capacitor in an on-line state.

3. The method as claimed in claim 1, wherein k is a correction factor for the capacitance change rate of the support capacitor₁：

Wherein the dielectric loss tangent of the support capacitor is denoted as tan delta_wWherein δ_wThe dielectric loss angle is expressed by radian; the measured capacitance value is denoted as C, unit uF.

4. The method as claimed in claim 1, wherein k is a failure factor of insulation failure of the support capacitor when calculating₂：

Wherein the insulation resistance of the support capacitor is represented as R, and the dielectric loss tangent value of the support capacitor is represented as tan delta_w。

5. The method as claimed in claim 1, wherein the residual life L of the support capacitor_(t)The calculation is as follows:

record life expectancy as L₍₀₎Failure factor k for support capacitor insulation failure₂Correction factor k for supporting the rate of change of capacitance value of capacitor₁Eta is life loss factor of capacitor in overload operation, measured capacitance is marked as C, and delivery capacity on appearance nameplate of support capacitor is marked as C₀。

6. The auxiliary power supply support capacitance monitoring method of claim 1, wherein an insulation resistance between the support capacitance electrode and ground is measured by an insulation resistance meter.

7. The method as claimed in claim 1, wherein the testing method is to perform the test under the non-operating condition of the auxiliary power supply supporting capacitor, and the test is performed when a plurality of capacitors are present, and the test is performed when the plurality of capacitors are measured under one time node.

8. An auxiliary power supply supports electric capacity monitoring system, characterized by includes:

the measuring unit is used for measuring the dielectric loss tangent value and the capacitance value of the support capacitor;

the correction factor calculation unit is used for calculating the correction factor of the capacitance value change rate of the support capacitor based on the measured dielectric loss tangent value and the capacitance value of the support capacitor;

an insulation resistance measuring unit for measuring an insulation resistance of the support capacitor;

the supporting capacitor insulation failure factor calculation unit is used for calculating a supporting capacitor insulation failure factor based on the insulation resistance of the measured supporting capacitor, the measured supporting capacitor dielectric loss tangent value and the measured capacitance value;

and the monitoring unit is used for monitoring the residual service life of the support capacitor of the auxiliary power supply based on the insulation failure factor of the support capacitor and the correction factor of the capacitance value change rate of the support capacitor.

9. A computing device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the program performs the steps of the method of any one of claims 1 to 7.

10. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, is adapted to carry out the steps of the method according to any one of the preceding claims 1 to 7.

Technical Field

The invention belongs to the technical field of support capacitance testing, and particularly relates to a method and a system for monitoring support capacitance of an auxiliary power supply.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

The motor train unit system is developed comprehensively in recent years, and compared with other traffic systems, the motor train unit system has many advantages in the aspects of traffic capacity, energy efficiency, operation cost and environmental friendliness. With the continuous improvement of the running speed of the motor train unit, higher requirements are provided for the running safety and reliability of the motor train unit.

The support capacitor is one of core reactive devices designed and used on the motor train unit, and plays roles in buffering energy exchange between an alternating current side and a direct current side, stabilizing intermediate direct current voltage, storing energy and providing instantaneous energy exchange. With the increase of the service mileage of the motor train unit, the support capacitor can age and damage the internal insulation medium polypropylene film under the combined action of main external stress, namely electrical stress and thermal stress, so that the insulation performance and the electrical parameters of the support capacitor are reduced to some extent, and the service life of the support capacitor is further influenced.

The service life evaluation method for the support capacitor on the motor train unit mainly comprises the step of carrying out durability test under the condition that the support capacitor is offline, but the method needs long time and damages the internal insulation of the capacitor, so that the reliability of evaluation is influenced, and the capacitor cannot be continuously and normally used.

Disclosure of Invention

In order to solve the problems, the invention provides a method for monitoring the supporting capacitor of the auxiliary power supply, which can reliably and efficiently evaluate the use reliability and safety of the supporting capacitor.

According to some embodiments, the invention adopts the following technical scheme:

in a first aspect, a method for monitoring support capacitance of an auxiliary power supply is disclosed, which includes:

measuring the dielectric loss tangent value and the capacitance value of the support capacitor;

calculating a correction factor of the capacitance value change rate of the support capacitor based on the measured dielectric loss tangent value and the capacitance value of the support capacitor;

measuring the insulation resistance of the support capacitor;

calculating an insulation failure factor of the support capacitor based on the insulation resistance of the support capacitor, the measured dielectric loss tangent value and the measured capacitance value of the support capacitor;

and monitoring the residual service life of the support capacitor of the auxiliary power supply based on the insulation failure factor of the support capacitor and the correction factor of the capacitance value change rate of the support capacitor.

According to the further technical scheme, the dielectric loss tangent value, the capacitance value and the insulation resistance of the support capacitor are obtained in an online state.

In the further technical scheme, when the correction factor of the change rate of the capacitance value of the support capacitor is calculated, the correction factor is recorded as k₁：

Wherein the dielectric loss tangent of the support capacitor is denoted as tan delta_wWherein δ_wThe dielectric loss angle is expressed by radian; the measured capacitance value is denoted as C, unit uF.

According to the further technical scheme, when the failure factor of the insulation failure of the support capacitor is calculated, the failure factor is recorded as k₂：

Wherein the insulation resistance of the support capacitor is represented as R, and the dielectric loss tangent value of the support capacitor is represented as tan delta_w。

Further technical solution, the remaining life L of the support capacitor_(t)The calculation is as follows:

record life expectancy as L₍₀₎Failure factor k for support capacitor insulation failure₂Correction factor k for supporting the rate of change of capacitance value of capacitor₁Eta is life loss factor of capacitor in overload operation, measured capacitance is marked as C, and delivery capacity on appearance nameplate of support capacitor is marked as C₀。

In a second aspect, an auxiliary power supply support capacitance monitoring system is disclosed, comprising:

the measuring unit is used for measuring the dielectric loss tangent value and the capacitance value of the support capacitor;

the correction factor calculation unit is used for calculating the correction factor of the capacitance value change rate of the support capacitor based on the measured dielectric loss tangent value and the capacitance value of the support capacitor;

an insulation resistance measuring unit for measuring an insulation resistance of the support capacitor;

the supporting capacitor insulation failure factor calculation unit is used for calculating a supporting capacitor insulation failure factor based on the insulation resistance of the measured supporting capacitor, the measured supporting capacitor dielectric loss tangent value and the measured capacitance value;

and the monitoring unit is used for monitoring the residual service life of the support capacitor of the auxiliary power supply based on the insulation failure factor of the support capacitor and the correction factor of the capacitance value change rate of the support capacitor.

Compared with the prior art, the invention has the beneficial effects that:

according to the method for evaluating the residual life of the support capacitor of the auxiliary power supply device of the motor train unit, the correction factor and the insulation failure factor of the change rate of the capacitance value of the support capacitor are calculated by measuring the dielectric loss tangent value, the capacitance value and the insulation resistance to the ground, and finally the residual life of the support capacitor is evaluated.

According to the invention, the disassembly and the assembly of field workers on the supporting capacitor of the auxiliary power supply device of the motor train unit are avoided, the residual service life of the supporting capacitor of the auxiliary power supply device of the motor train unit can be conveniently, accurately and safely evaluated in a short time without damaging the internal insulation of the supporting capacitor, the use reliability of the supporting capacitor is ensured, and the running safety of the motor train unit is further ensured.

Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a flowchart of an assessment method for the remaining life of a support capacitor of an auxiliary power supply device of a motor train unit.

The specific implementation mode is as follows:

the invention is further described with reference to the following figures and examples.

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all 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.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The first embodiment is as follows:

in the embodiment, the supporting capacitor of the auxiliary power supply device of the motor train unit is used for illustration, but the method and the system provided by the invention are not only applicable to the supporting capacitor of the auxiliary power supply device of the motor train unit. The auxiliary power supply device can be suitable for other auxiliary power supply device supporting capacitors according to different test scenes or test objects. The problem that in the prior art, the capacitor on the vehicle is disassembled to carry out durability test, so that the insulation of the capacitor is damaged, and the subsequent use cannot be carried out is solved.

Specifically, referring to fig. 1, a method for monitoring the supporting capacitance of an auxiliary power supply includes:

the method comprises the following steps of measuring a dielectric loss tangent value and a capacitance value of a support capacitor, wherein the method comprises the following steps: the dielectric loss tangent value of the support capacitor is measured by using an LCR digital bridge and is recorded as tan delta_wWherein δ_wDielectric loss angle (expressed in radians); the measured capacitance value is marked as C, unit uF; reading the delivery capacity on the appearance nameplate of the support capacitor and recording as C₀The unit uF;

when the method is realized, LCR digital bridge equipment is used, and the test can be performed after the LCR digital bridge equipment is connected according to the wiring, so that data can be directly obtained.

And step two, calculating a correction factor of the supporting capacitance value change rate, and calculating the correction factor of the supporting capacitance value change rate according to the formula (1), and recording the correction factor as k 1:

the self-healing characteristic of the metallized film is considered by adopting a correction factor for supporting the capacitance value change rate of the capacitor; the data obtained can be implemented programmatically/manually.

Step three: measuring the insulation resistance of the support capacitor, and measuring the insulation resistance between the electrode of the support capacitor and the ground by using an insulation resistance meter, wherein the insulation resistance is recorded as R and the unit is M omega;

step four: calculating the insulation failure factor of the support capacitor, and calculating the insulation of the support capacitor according to the formula (2)Failure factor of failure, denoted k₂：

The insulation failure factor of the support capacitor is characterized by insulation resistance and dielectric loss in consideration of the influence of various factors such as temperature, humidity and the like on the insulation performance in the capacitor; programmable implementations may also be calculated manually.

Step five, calculating the residual service life of the support capacitor, comprising the following steps: checking an initial factory inspection report of the support capacitor to be evaluated, recording the expected life of the support capacitor to be evaluated before factory operation, and recording the expected life as L₍₀₎Setting the remaining life L of the support capacitor after the operating time t (hours)_(t)The remaining life of the support capacitor can be calculated according to equation (3):

wherein eta is a life loss factor under the condition of the capacitor overload operation, and is 0.00001.

The calculation mode comprehensively considers various electrical parameters of the support capacitor, the actual condition of the support capacitor can be comprehensively and comprehensively reflected, and the required electrical parameters can be obtained through conventional tests.

The method can accurately and conveniently acquire the residual service life condition of the supporting capacitor of the auxiliary power supply device of the motor train unit under the condition of not damaging the internal insulation of the supporting capacitor, and is used for directly calculating the approximate residual service time of the capacitor.

The test of the scheme is carried out in a non-operating state and is obtained by measuring under a time node, and a plurality of capacitors can only be tested respectively.

The invention comprehensively utilizes the dielectric loss factor, the current/factory capacitance value, the ground insulation resistance and other electrical parameters to evaluate the residual service life of the support capacitor, and improves the accuracy and reliability of evaluation.

The method does not need to consider the operating voltage grade of the supporting capacitor of the auxiliary power supply device of the motor train unit, can be suitable for supporting capacitors under any voltage grade, and has certain universality.

Example two:

based on the system of the first embodiment, specifically, an auxiliary power supply supports electric capacity monitoring system includes:

the measuring unit is used for measuring the dielectric loss tangent value and the capacitance value of the support capacitor;

the correction factor calculation unit is used for calculating the correction factor of the capacitance value change rate of the support capacitor based on the measured dielectric loss tangent value and the capacitance value of the support capacitor;

an insulation resistance measuring unit for measuring an insulation resistance of the support capacitor;

the supporting capacitor insulation failure factor calculation unit is used for calculating a supporting capacitor insulation failure factor based on the insulation resistance of the measured supporting capacitor, the measured supporting capacitor dielectric loss tangent value and the measured capacitance value;

and the monitoring unit is used for monitoring the residual service life of the support capacitor of the auxiliary power supply based on the insulation failure factor of the support capacitor and the correction factor of the capacitance value change rate of the support capacitor.

The specific embodiment comprises two parts of software and hardware, wherein the software is a related program written by Matlab 2019; the hardware comprises an LCR digital bridge measuring instrument and an insulation resistance instrument.

Example three:

it is an object of this embodiment to provide a computing device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing the steps of the above method when executing the program.

Example four

An object of the present embodiment is to provide a computer-readable storage medium.

A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the above-mentioned method.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention 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 present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. 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.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.