Online evaluation and result simplification method for electric energy quality of coal mine tunneling equipment

Abstract

The invention belongs to the technical field of coal mine underground power supply system analysis, and provides a coal mine tunneling equipment power quality on-line evaluation and result simplification method in order to solve the problem that at present, a tunneling working face lacks an electric energy quality evaluation scheme for monitoring the running state of tunneling working face equipment on line. A matched electric energy quality index system is provided according to the actual situation that the distance between tunneling equipment and a mobile substation is long, and then the weight of each electric energy quality index is obtained based on an analytic hierarchy process according to the influence of electric energy quality indexes of different power supplies on the tunneling equipment; and finally, a simple electric energy quality evaluation result which meets the requirements of monitoring and operators is obtained and displayed through a simple data filtering means, the current electric energy quality condition is obtained in real time, and early warning is provided, so that corresponding means are adopted in time, and the electric energy quality evaluation efficiency is improved. For example, an electric energy quality treatment device is mounted in a characteristic area or position of a tunneling roadway or tunneling equipment, so that the operation efficiency of the tunneling equipment and the safety of the equipment are effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mine underground power supply system analysis, and in particular relates to an online evaluation method for power quality of coal mine excavation equipment and a result simplification method. Background Art

[0002] For large underground mines, the underground power supply system mainly adopts a four-level power distribution method of central distribution station, mining area transformer / distribution station, mobile substation, and working face load center. With the extension of the tunneling tunnel, the distance between the working equipment of the tunneling face and the mobile substation can reach 2000m to 3500m. The serious voltage drop on the long-distance power supply cable makes the voltage at the end of the tunneling equipment low, making it difficult or even impossible to start the equipment. In addition to voltage deviation, power quality problems such as power supply frequency deviation, harmonic content, and three-phase voltage imbalance on the tunneling equipment side will affect the normal operation of high-power motors in the tunneling equipment. At the least, it will cause the equipment to fail to start normally, and at the worst, it will cause abnormal damage to the equipment, seriously affecting the continuity and safety of tunneling production.

[0003] At present, it is a consensus that there are power quality problems in the tunneling working face. In the engineering design stage of the mine, the severity of the power quality problems of the working face is estimated through theoretical calculation and other methods, and then the power supply and distribution equipment such as cables are selected based on this. However, with the upgrading and replacement of underground tunneling equipment, the total power of the equipment has increased, and the number of high-power power electronic devices has increased, which has aggravated the power quality problems of the tunneling working face. It is inevitable that the power quality management measures for power supply are insufficiently estimated, inaccurate, and ineffective. Therefore, there is an urgent need for an evaluation method that can evaluate the power quality of tunneling equipment in real time online, and display the evaluation results in a timely manner, so as to facilitate the discovery of potential power quality problems of tunneling equipment. Summary of the invention

[0004] In order to solve at least one of the above technical problems existing in the prior art, the present invention provides a method for online evaluation and result simplification of power quality of coal mine excavation equipment.

[0005] The present invention is implemented by the following technical solution: a method for online evaluation and result simplification of power quality of coal mine excavation equipment, comprising the following steps:

[0006] Collect power quality index data, and establish a power quality index matrix based on the power quality index data collected within a limited time;

[0007] Based on the power quality level index limit, the data in the power quality index matrix is ​​processed positively to obtain the power quality index score of the tunneling equipment;

[0008] Using the analytic hierarchy process, the importance judgment matrix of power quality indicators is constructed, and the weight of each power quality indicator is determined;

[0009] Based on the power quality index score of the tunneling equipment and the index weight, an initial evaluation result of the corresponding power quality is obtained;

[0010] The initial evaluation results within a limited time are simplified according to the preset minimum simplicity period to obtain the minimum value of the initial evaluation results, which is used as the final evaluation result.

[0011] Preferably, the construction of the power quality index importance judgment matrix includes:

[0012] Based on the influence of power quality indicators of different power supplies on tunneling equipment, a power quality indicator importance judgment matrix is ​​constructed according to the importance scaling method, and a consistency check is performed on the power quality indicator importance judgment matrix. When the check passes, the indicator weight of each power quality indicator is determined; otherwise, the power quality indicator importance judgment matrix is ​​reconstructed according to different power quality indicators.

[0013] Preferably, performing consistency check on the power quality indicator importance judgment matrix includes:

[0014] Calculate the maximum eigenvalue of the power quality index importance judgment matrix, and obtain the consistency index according to the number of compared indicators in the power quality index importance judgment matrix;

[0015] Calculating a consistency ratio according to the consistency index and an average random consistency index obtained by looking up a table;

[0016] The consistency ratio is compared with a preset ratio threshold. If the consistency ratio is less than the preset ratio threshold, the consistency check is passed.

[0017] Preferably, determining the indicator weight of each power quality indicator includes:

[0018] Calculate and obtain the eigenvector of the power quality index importance judgment matrix;

[0019] According to the preset constraint conditions and the characteristic vector, the indicator weight of each power quality indicator is determined.

[0020] Preferably, obtaining the power quality index score of the tunneling equipment includes:

[0021] Obtain the power quality index classification table;

[0022] Based on the power quality index classification table, determine the power quality index limit, and then perform index positive processing on the power quality index;

[0023] The power quality index score of the tunneling equipment is obtained based on the power quality index after the forward processing.

[0024] Preferably, the initial evaluation result of power quality is:

[0025] Y=Uw=[y1,…,y T ]'

[0026] Among them, U is the power quality index score, w is the index weight, and T is the limited time.

[0027] Preferably, the simplified power quality assessment result is:

[0028] y * =min([y1,…,y T ]).

[0029] Preferably, the initial evaluation result of the power quality is an evaluation result matrix arranged in chronological order within a limited time. The evaluation result matrix is ​​segmented according to the minimum simple period, and the minimum value in each segment is selected as the evaluation result corresponding to the minimum simple period. The evaluation results corresponding to all minimum simple periods are arranged in chronological order within a limited time to obtain a simplified power quality evaluation result.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] According to the actual situation that the tunneling equipment is far away from the mobile substation, the present invention proposes a matching power quality indicator system, and then obtains the weight of each power quality indicator based on the hierarchical analysis method according to the impact of the power quality indicators of different power supplies on the tunneling equipment. Finally, a simple data filtering method is used to obtain a simple power quality evaluation result display that meets the needs of monitoring and operating personnel. The tunneling equipment operator can know the current power quality situation in real time and provide an early warning, so as to take corresponding measures in time, such as installing a power quality management device in the characteristic area or position of the tunneling tunnel or the tunneling equipment, etc., so as to effectively improve the operating efficiency of the tunneling equipment and the safety of the equipment itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A block diagram of the power quality indicator system provided by the present invention;

[0034] Figure 2An algorithm flow chart of an online evaluation method for power quality of coal mine excavation equipment and a result simplification method provided by the present invention;

[0035] Figure 3 The voltage and current waveform diagram of the tunneling equipment during cutting according to the embodiment of the present invention;

[0036] Figure 4 This is a voltage and current waveform diagram when the tunneling equipment according to an embodiment of the present invention is started;

[0037] Figure 5 This is a voltage and current waveform diagram when the tunneling equipment according to an embodiment of the present invention is shut down;

[0038] Figure 6 is the power quality assessment score when the fixed finite time length is 0.25s in the embodiment of the present invention;

[0039] Figure 7 is an online power quality assessment score without data reduction in an embodiment of the present invention;

[0040] Figure 8 It is a simplified power quality fraction sequence diagram when the simplified period is 1s in an embodiment of the present invention;

[0041] Fig. 9 This is a simplified power quality fraction sequence diagram when the simplified period is 2s in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In conjunction with the drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0043] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention. It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0044] The power quality indicators of tunneling working face equipment include voltage deviation, voltage fluctuation, voltage three-phase imbalance, voltage total harmonic distortion rate, power factor, frequency deviation, etc. Real-time monitoring of the above parameters of tunneling working face equipment can accurately judge the operating status of the access equipment. The over-limit of a single indicator or several indicators may be normal under certain working conditions. Therefore, it is necessary to integrate various power quality indicators to form a single evaluation result for monitoring and operation personnel to judge. At the same time, the display of online evaluation results will also affect the judgment of monitoring and operation personnel on the power quality of tunneling equipment. When the evaluation result calculation frequency is too fast or even consistent with the data acquisition frequency, the information revealing the tunneling power quality problem will be submerged in a large amount of useless information and will not be noticed; when the evaluation result calculation frequency is too slow, the result display will lack the detailed display of the equipment operation status evaluation result, and lack the basis for judging the power quality problem of tunneling equipment. Therefore, in order to solve the problem of the lack of online monitoring of the power quality evaluation scheme of tunneling working face equipment operation status at present, a method of online evaluation and result simplification of power quality of coal mine tunneling equipment is proposed.

[0045] Before implementing the following embodiments of the present invention, a matching power quality index system should be proposed based on the actual situation and operating characteristics of the tunneling equipment in the tunneling working face, such as voltage frequency deviation may cause the asynchronous motor to change its operating speed or even damage it, and voltage deviation may cause the motor to fail to start normally. The power quality index system established in the embodiments of the present invention is as follows: Figure 1 As shown, including power factor, voltage deviation, voltage three-phase unbalance, voltage fluctuation, voltage flicker, voltage total harmonic distortion rate, and frequency deviation.

[0046] The embodiment of the present invention provides a method for online evaluation of power quality of coal mine excavation equipment and result simplification, such as Figure 2 As shown, the following steps are included:

[0047] S1: Collect power quality index data, and establish a power quality index matrix based on the power quality index data collected within a limited time;

[0048] S2: Based on the power quality level index limit, the data in the power quality index matrix is ​​forward processed to obtain the power quality index score of the tunneling equipment;

[0049] S3: Use the analytic hierarchy process to construct a power quality index importance judgment matrix and determine the index weights of each power quality index;

[0050] S4: Based on the power quality index score of the tunneling equipment and the index weight, obtaining an initial evaluation result of the corresponding power quality;

[0051] S5: Simplify the initial evaluation results within a limited time according to a preset minimum simplification period to obtain the minimum value of the initial evaluation results, and use it as the final evaluation result.

[0052] In this embodiment, the voltage and current sequence waveforms of the start-up, cutting and shutdown of the tunneling equipment are collected, such as Figure 3-Figure 5 shown.

[0053] In this embodiment, an existing power quality analyzer can be installed on the side of the switch cabinet about 100 meters away from the tunneling equipment, and data can be obtained through wired or wireless transmission. The collected power quality index data is as follows: Figure 1 shown.

[0054] The power quality index matrix X established based on the power quality index data collected within a limited time is:

[0055]

[0056] Among them, x tm is the mth power quality index at the tth time point, T is the number of finite time points, and M is the total number of power quality indicators.

[0057] Optionally, obtaining the power quality index score of the tunneling equipment includes: obtaining a power quality index grade classification table; determining the power quality grade index limit based on the power quality index grade classification table, and then performing index positive processing on the power quality index; and obtaining the power quality index score of the tunneling equipment based on the power quality index after the positive processing.

[0058] In this embodiment, some indicators such as voltage deviation are judged as smaller as possible, while the final power quality evaluation result should be as large as possible, which is not conducive to the calculation of power quality evaluation results. The indicator is positively processed to transform it into an evaluation standard where the larger the indicator score, the better. According to the current domestic power quality indicator level and value correspondence, the power quality indicators are divided into 5 levels as shown in Table 1:

[0059] Table 1

[0060] index type I II III IV V Voltage fluctuation / % cost ≤0.5 ≤1.0 ≤1.5 ≤2.0 ＞2.0 Voltage deviation / % cost ≤1.2 ≤3.0 ≤4.5 ≤7.0 ＞7.0 Voltage harmonics / % cost ≤1.0 ≤2.0 ≤3.0 ≤5.0 ＞5.0 Voltage flicker / % cost ≤0.2 ≤0.5 ≤0.8 ≤1.0 ＞1.0 Voltage sag / % benefit ≥0.9 ≥0.8 ≥0.5 ≥0.1 ＜0.1 Frequency deviation / % cost ≤0.05 ≤0.1 ≤0.15 ≤0.2 ＞0.2 Three-phase unbalance / % cost ≤0.5 ≤1.0 ≤1.5 ≤2.0 ＞2.0

[0061] In this embodiment, taking the computer quality level indicator limit shown in the fifth level indicator as an example, the power quality indicator matrix is ​​processed into a power quality indicator score, and the voltage fluctuation, voltage deviation, voltage harmonics, voltage flicker, frequency deviation, and three-phase imbalance indicators are positively processed according to the "greater than" and "less than" symbols in Table 1.

[0062] The processed indicators are u tm :

[0063]

[0064] Among them, u tm is the forward processing value of the mth power quality index at the tth time point, is the index limit of the mth power quality index under the jth level type. The power quality index score U after positive transformation is:

[0065]

[0066] Optionally, constructing a power quality indicator importance judgment matrix includes: constructing a power quality indicator importance judgment matrix according to an importance scaling method based on the impact of power quality indicators of different power supplies on tunneling equipment, performing a consistency check on the power quality indicator importance judgment matrix, and when the check passes, determining the indicator weights of each power quality indicator; otherwise, reconstructing the power quality indicator importance judgment matrix based on different power quality indicators.

[0067] Optionally, a consistency check is performed on the power quality indicator importance judgment matrix, including: calculating the maximum eigenvalue of the power quality indicator importance judgment matrix, and obtaining a consistency index based on the number of compared indicators in the power quality indicator importance judgment matrix; calculating a consistency ratio based on the consistency index and an average random consistency index obtained by table lookup; and comparing the consistency ratio with a preset ratio threshold. If the consistency ratio is less than the preset ratio threshold, the consistency check is passed.

[0068] Optionally, determining the indicator weight of each power quality indicator includes: calculating the eigenvector of the power quality indicator importance judgment matrix; and determining the indicator weight of each power quality indicator according to preset constraints and the eigenvector.

[0069] In this embodiment, when there are many power quality indicator systems, Figure 1 As shown, it is decomposed into several layers from top to bottom. The factors in the same layer are subordinate to the factors in the upper layer or have an influence on the factors in the upper layer, and at the same time dominate the factors in the lower layer or are affected by the factors in the lower layer. The highest layer is the target layer, which is the ultimate goal to be achieved; the criterion layer below it can be further decomposed into sub-criteria layers when there are too many criteria; the bottom layer is composed of multiple indicators. At the criterion layer and the indicator layer, the influence of the power quality indicators of different power supplies on the tunneling equipment can be used. The embodiment of the present invention uses the 1-9 scaling method to calculate the weights of different quasi-layers and indicators. The 1-9 scaling method is shown in Table 2:

[0070] Table 2

[0071] Scale meaning 1 Indicates that two elements have the same importance. 3 Indicates that compared with two elements, the former is slightly more important than the latter 5 Indicates that compared with two elements, the former is obviously more important than the latter 7 Indicates that compared with two elements, the former is extremely important than the latter 9 Indicates that compared with two elements, the former is more important than the latter 2、4、6、8 Indicates the middle value of the above adjacent judgments Count down from 1 to 9 Indicates the importance of swapping the corresponding two elements

[0072] According to the importance scaling method in Table 2, the power quality index importance judgment matrix A is constructed:

[0073]

[0074] Among them, a kk’ is the importance of the kth indicator compared to the k'th indicator, and K is the number of indicators selected for comparison.

[0075] In this embodiment, whether the power quality index importance judgment matrix satisfies consistency is determined according to the consistency ratio test, wherein the consistency ratio CR is calculated by the consistency index CI and the average random consistency index RI, and the consistency index CI is:

[0076]

[0077] In the formula, λ max is the maximum eigenvalue of the power quality index importance judgment matrix.

[0078] The average random consistency index RI is obtained by looking up the table, as shown in Table 3:

[0079] Table 3

[0080]

[0081] The consistency ratio CR is:

[0082]

[0083] If CR<0.1, it indicates that the power quality indicator importance judgment matrix A passes the consistency test. The eigenvector corresponding to each power quality indicator is calculated according to the power quality indicator importance judgment matrix. The indicator weight of each power quality indicator is determined according to the preset constraints and the eigenvector. Otherwise, the power quality indicator importance judgment matrix is ​​reconstructed.

[0084] In this embodiment, the maximum eigenvalue λ is solved according to the data in the power quality index importance judgment matrix. max , and set the constraint condition as: the 1-norm of w is 1, that is, ||w||1=1, and get the corresponding eigenvector w.

[0085] In this embodiment, Figure 1Taking the criterion layer in as an example, the frequency index determines whether the motor of the tunneling equipment can operate normally without failure, and its importance is higher than the voltage index and power index; the voltage deviation in the voltage index determines whether the motor can start normally under long-distance power supply, and its importance is higher than the voltage three-phase imbalance or the voltage total harmonic distortion rate. Based on this, the criterion layer power quality index importance judgment matrix A1 of the criterion layer voltage index, frequency index, and power index is established:

[0086]

[0087] The consistency index is verified to be: 0.0559<0.1. The consistency index verification is satisfied and there is no need to reconstruct the judgment matrix. The weight is calculated as w1=[0.279, 0.0719, 0.6491].

[0088] Secondly, the power quality index importance judgment matrix A2 of the index layer voltage deviation, voltage fluctuation, voltage flicker, voltage total harmonic distortion rate, and voltage three-phase imbalance is established:

[0089]

[0090] The consistency index is verified to be: 0.0928<0.1. The consistency index verification is met and there is no need to reconstruct the judgment matrix. The weight is calculated as w2=[0.5080, 0.0757, 0.0335, 0.2513, 0.1314].

[0091] The indicator layer voltage deviation, voltage fluctuation, voltage flicker, voltage total harmonic distortion rate, voltage three-phase unbalance belong to the voltage indicator, power factor belongs to the power indicator, and frequency deviation belongs to the frequency indicator. Based on the above product method, the final weight of the power quality indicator is calculated. Combining w1 and w2, the indicator weight w of voltage deviation, voltage fluctuation, voltage flicker, voltage total harmonic distortion rate, voltage three-phase unbalance, frequency deviation, and power factor is:

[0092] w=[[0.5080,0.0757,0.0335,0.2513,0.1314]*0.279,0.0719,0.6491]

[0093] Then normalize its 1-norm:

[0094] w=[0.1955,0.2913,0.1289,0.0967,0.0506,0.0992,0.1379].

[0095] In this embodiment, the power quality index score U and the index weight w after forwardization are comprehensively considered, and the initial evaluation result Y of the power quality of M power quality indicators at the excavation working face at a finite time T is directly calculated as shown below. The larger the value of the initial evaluation result, the better the power quality status of the current excavation equipment.

[0096] Y=Uw=[y1,…,y T ]'

[0097] Among them, U is the power quality index score, w is the index weight, and T is the limited time.

[0098] like Figure 6 The figure shows the power quality evaluation score obtained by the power quality index score collected when the fixed finite time length is 0.25s according to the hierarchical analysis method. Figure 6 The score range of power quality level I to level V is marked in the figure. The score range is calculated based on the limit values ​​in Table 1. The range can be judged and calibrated by yourself.

[0099] In this embodiment, referring to the working characteristics of tunneling equipment, the minimum simplified period is set to the finite time length, that is, the data simplified period of the tunneling equipment power quality assessment is taken as 1~2s, that is, the finite time length T is 1~2s, and the data simplification method adopts the minimum value method. Taking the number of finite time points Y as an example, the online power quality assessment result y after the simplified assessment result is * for:

[0100] y * =min([y1,…,y T ])

[0101] Optionally, the initial evaluation result of the power quality is an evaluation result matrix arranged in chronological order within a limited time. The evaluation result matrix is ​​segmented according to the minimum simple period, and the minimum value in each segment is selected as the evaluation result corresponding to the minimum simple period. The evaluation results corresponding to all minimum simple periods are arranged in chronological order within a limited time to obtain a simplified power quality evaluation result.

[0102] In this embodiment, the power quality index collection frequency of the power quality analyzer is 3-10 Hz. This sampling frequency is too high and is not conducive to the display of evaluation results. Figure 7 As shown in Table 4, due to errors or interference in the data acquisition equipment, there is a jump in the power quality assessment score, which is likely to interfere with the judgment of the monitoring and operating personnel. Therefore, data simplification is required. The power quality standard data simplification method of the public power grid is shown in Table 4:

[0103] Table 4

[0104] Indicator parameters Simple Cycle Data parsimony methods Frequency Deviation - - Voltage deviation 3s, 1min, 10min average value Voltage small balance Integer multiples of 1min average value harmonic - - Interharmonics 3min、10min RMS

[0105] The simplified cycle of the public power grid is mostly 1-10 minutes long, and the data simplification method adopts the average value or root mean square. During the working process of the tunneling equipment, the simplified cycle length of 1-10 minutes is similar to the cutting process of the tunneling drill bit, and is much longer than the motor starting process. At the same time, the cutting drill bit is an impact load, and the data processing method of the average value or root mean square will process the poor power quality data of the local process as normal, thereby hiding the potential power quality problems of the equipment.

[0106] In this embodiment, in order to ensure that the simplified processed data is convenient for the equipment operator to monitor, the power quality problems of the equipment are exposed as much as possible during the display process. The power quality status of the tunneling equipment is displayed according to the simplified power quality evaluation results. The smaller the simplified evaluation result is, the worse the power quality status of the tunneling equipment is. When the embodiment of the present invention is operated in an online form, after inputting the collected power quality index data, a power quality evaluation result matrix Y1, ..., Y2, arranged in chronological order, is generated. N , after data simplification, it will be processed into y1 arranged in chronological order * ,...,y N * , and is presented in the form of an image. Figure 8 , Fig. 9 As shown, Figure 8 This is the simplified sequence result diagram of the power quality fraction when the simplified cycle is 1s. Fig. 9 The figure shows the simplified sequence result of the power quality fraction when the simplified cycle is 2s. Figure 8 and Fig. 9 The score range of power quality level I to level IV is marked in the figure. The score range is calculated based on the limit values ​​in Table 1. The range can be judged and calibrated by yourself. After data simplification, the problems reflected by the power quality score will be magnified. Although the power quality value displayed in real time by the tunneling equipment is reduced to a certain extent, it is easier for operators or equipment managers to notice situations when the power quality score is extremely small or does not meet the corresponding level, thereby discovering equipment problems in time.

[0107] According to the actual situation that the tunneling equipment is far away from the mobile substation, the present invention proposes a matching power quality index system, and then obtains the weight of each power quality index based on the analytic hierarchy process according to the influence of the power quality indicators of different power supplies on the tunneling equipment, and finally obtains a simple power quality evaluation result display that meets the needs of monitoring and operators through a simple data filtering method. The tunneling equipment operator can know the current power quality situation in real time and provide early warning, so as to take corresponding measures in time, such as installing power quality management devices in the characteristic areas or positions of the tunneling tunnel or tunneling equipment, etc., effectively improving the operating efficiency of the tunneling equipment and the safety of the equipment itself.

[0108] The present invention mainly proposes an online evaluation method of the power quality of coal mine excavation equipment and a method for simplifying the results for the excavation equipment at the excavation working face. For other similar equipment with power quality problems and situations where online monitoring of equipment power quality is required to achieve real-time early warning, the method provided by this patent can be used as a reference.

[0109] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for online evaluation and result simplification of power quality of coal mine excavation equipment, characterized in that: The steps include: Collect power quality index data, and establish a power quality index matrix based on the power quality index data collected within a limited time; Based on the power quality level index limit, the data in the power quality index matrix is ​​processed positively to obtain the power quality index score of the tunneling equipment; Using the analytic hierarchy process, the importance judgment matrix of power quality indicators is constructed, and the weight of each power quality indicator is determined; Based on the power quality index score of the tunneling equipment and the index weight, an initial evaluation result of the corresponding power quality is obtained; The initial evaluation results within a limited time are simplified according to the preset minimum simplicity period to obtain the minimum value of the initial evaluation results, which is used as the final evaluation result.

2. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 1 is characterized in that: The construction of the power quality index importance judgment matrix includes: Based on the influence of power quality indicators of different power supplies on tunneling equipment, a power quality indicator importance judgment matrix is ​​constructed according to the importance scaling method, and a consistency check is performed on the power quality indicator importance judgment matrix. When the check passes, the indicator weight of each power quality indicator is determined; otherwise, the power quality indicator importance judgment matrix is ​​reconstructed according to different power quality indicators.

3. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 2 is characterized in that: The consistency check of the power quality index importance judgment matrix is ​​performed, including: Calculate the maximum eigenvalue of the power quality index importance judgment matrix, and obtain the consistency index according to the number of compared indicators in the power quality index importance judgment matrix; Calculating a consistency ratio according to the consistency index and an average random consistency index obtained by looking up a table; The consistency ratio is compared with a preset ratio threshold. If the consistency ratio is less than the preset ratio threshold, the consistency check is passed.

4. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 2 is characterized in that: Determine the indicator weights of various power quality indicators, including: Calculate and obtain the characteristic vectors in the power quality index importance judgment matrix; According to the preset constraint conditions and the characteristic vector, the indicator weight of each power quality indicator is determined.

5. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 1, characterized in that: The obtained power quality index score of tunneling equipment includes: Obtain the power quality index classification table; Based on the power quality index classification table, determine the power quality index limit, and then perform index positive processing on the power quality index; The power quality index score of the tunneling equipment is obtained based on the power quality index after the forward processing.

6. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 1, characterized in that: The initial assessment results of power quality are: Y=Uw=[y1,…,y T ]' Among them, U is the power quality index score, w is the index weight, and T is the limited time.

7. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 6, characterized in that: The simplified power quality assessment results are: y * =min([y1,…,y T ])。 8. The method for online evaluation and result simplification of power quality of coal mine excavation equipment according to claim 7, characterized in that: Also includes: The initial evaluation result of the power quality is an evaluation result matrix arranged in chronological order within a limited time. The evaluation result matrix is ​​segmented according to the minimum simple period, and the minimum value in each segment is selected as the evaluation result corresponding to the minimum simple period. The evaluation results corresponding to all minimum simple periods are arranged in chronological order within a limited time to obtain the simplified power quality evaluation result.

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