Multistage starting system rotating part fault diagnosis method based on envelope attribution characteristics

Abstract

The invention relates to a multistage starting system rotating part fault diagnosis method based on envelope attribution characteristics, and the method comprises the steps: firstly estimating the three-phase current of an exciter rotor, calculating the average value of the sum of the absolute values of the three-phase current of the rotor, and obtaining the attribution time ratio of upper and lower envelope lines of the three-phase current of the rotor; the characteristic quantities such as the maximum value, the minimum value, the in-phase maximum difference value and the out-phase maximum difference value of the attribution time ratio are obtained and used for electrical fault diagnosis and positioning of the rotating part of the multistage starting system. The method provided by the invention can diagnose whether the rotating parts (including an exciter rotor winding, a rotating rectifier and a main motor excitation winding) of the multistage starting system have electrical faults on line, judge the fault type (an open-circuit fault or a short-circuit fault) and locate the specific position of a fault point. The method helps to make the multi-stage starting system more reliable and more convenient to maintain.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor fault diagnosis, and relates to a method for diagnosing faults of rotating parts of a multi-stage starting system based on envelope line attribution characteristics, and specifically to a method for online detection and positioning of electrical faults of rotating parts of a multi-stage brushless synchronous starting system based on upper and lower envelope line attribution characteristics of an exciter rotor current. Background Art

[0002] The multi-electric / all-electric aircraft is an important way to support the development of green aviation and improve aircraft performance, and has become an important direction for the development of future aircraft. With the increase in the capacity and types of onboard electrical equipment, the multi-electric / all-electric aircraft has higher and higher requirements for the high power density, high reliability, and high-quality power generation characteristics of the aviation power system, and the power system is facing more and more technical challenges. The aviation starting and power generation integrated system runs the aircraft generator in the electric state to drive the aircraft engine to start, and then the engine drives the generator to generate electricity after the start is completed. The original starter, accessory transmission case, and air bleed device and other equipment are discarded to achieve a reduction in system volume and weight and a simplification of the system structure, thereby greatly improving the efficiency, reliability and maintainability of the aircraft. Therefore, it has gradually gained widespread attention. Among various starting systems, the multi-stage brushless synchronous starting system has great potential in the application of aviation starting and power generation integration due to its high reliability and excellent power generation quality.

[0003] like Figure 1 As shown in the figure, a typical multi-stage brushless synchronous starting system consists of an auxiliary exciter, an exciter, a rotating rectifier and a main motor. Among them, the auxiliary exciter, the exciter and the main motor are coaxially connected to form a multi-stage motor structure. The exciter provides DC excitation current to the main motor through a rotating rectifier installed on the rotor side, realizing the brushless main motor (electrically excited synchronous motor) and adjustable excitation current. The rotating parts of the multi-stage starting system need to withstand large thermal and mechanical stresses during the high-speed rotation of the motor, and are components with a high failure rate. Therefore, conducting research on electrical fault diagnosis of rotating parts of the multi-stage starting system is of great significance to improving system reliability and maintainability.

[0004] The rotating parts of the multi-stage starting system mainly include the exciter rotor winding, rotating rectifier, and main motor excitation winding. These parts are all likely to have open circuit faults or short circuit faults, and need to be monitored in real time for their health status. That is, real-time diagnosis of whether the rotating parts have open circuit or short circuit faults is performed, which is called electrical fault diagnosis of the rotating parts of the multi-stage starting system.

[0005] The electrical fault diagnosis of the rotating parts of the multi-stage starting system requires the diagnosis of the fault type and the specific location of the fault, that is, whether the fault is a short circuit fault or an open circuit fault, the fault point is the exciter rotor winding, the rotating rectifier or the main motor excitation winding, and the specific fault occurs in a certain phase of the exciter rotor winding or a certain diode of the rotating rectifier, so as to facilitate the adoption of appropriate measures after the fault. At present, most of the fault diagnosis methods of multi-stage starting systems carry out fault diagnosis for one of the exciter winding, rotating rectifier or main motor winding separately, and there are few methods that can realize fault diagnosis and positioning for three rotating parts at the same time.

[0006] The present invention proposes an online diagnosis method for electrical faults of rotating parts of a multi-stage starting system based on the attribution characteristics of the upper and lower envelope lines of the three-phase current of the exciter rotor. The proposed method can realize online diagnosis of whether electrical faults occur in the rotating parts of the multi-stage starting system (including the exciter rotor winding, the rotating rectifier and the main motor excitation winding), determine the fault type and locate the fault point. Summary of the invention

[0007] Technical issues to be solved

[0008] In order to avoid the shortcomings of the prior art, the present invention proposes a fault diagnosis method for rotating parts of a multi-stage starting system based on envelope line attribution characteristics. Regarding the electrical fault diagnosis of rotating parts of a multi-stage starting system, the technical problems to be solved by the present invention are mainly: online diagnosis of whether an electrical fault occurs in the rotating parts of the multi-stage starting system (including the exciter rotor winding, the rotating rectifier and the main motor excitation winding), and determination of the fault type (open circuit or short circuit) and location of the specific position of the fault point.

[0009] Technical Solution

[0010] A method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics, characterized by the following steps:

[0011] Step 1: Based on the collected stator voltage and current of the exciter, estimate the three-phase current of the exciter rotor according to the voltage equation and flux equation of the exciter, denoted as i ar 、i br 、i cr ;

[0012] Step 2: Process the rotor three-phase current to obtain characteristic quantities;

[0013] The feature quantities include:

[0014] The sum of the absolute values ​​of the three-phase currents of the rotor in one cycle is i h The average value m h : The sum of the absolute values ​​of the three-phase current of the rotor i h =|i ar|+|i br |+|i cr |, using the sliding window mode to calculate the i within a cycle h The average value m h ;

[0015] The maximum difference in the time proportion of the upper and lower envelopes of the rotor three-phase current e max :e max =max{|t1-t4|,|t2-t5|,|t3-d6|};

[0016] The maximum difference d between the time proportions of the upper and lower envelopes of the rotor three-phase current max :d max =max{|t1-t2|,|t2-t3|,|t3-t1|,|t4-t5|,|t5-t6|,|t6-t4|};

[0017] The minimum value t of the time proportion of the upper and lower envelopes of the rotor three-phase current min :t min =min{t1,t2,t3,t4,t5,t6};

[0018] The maximum value t of the time proportion of the upper and lower envelopes of the rotor three-phase current max :t max =max{t1,t2,t3,t4,t5,t6};

[0019] The t1, t2, t3, t4, t5, and t6 are the attribution characteristics of the upper and lower envelopes of the rotor three-phase current;

[0020] Step 3: Perform electrical fault diagnosis of rotating components based on characteristic quantities and identify faulty components:

[0021] 3.1: m h The value is compared with the judgment threshold M1 of the open circuit fault of the main motor excitation winding:

[0022] When m h When ≤M1, it is judged that the main motor excitation winding has an open circuit fault;

[0023] When m h >M1, proceed to step 3.2;

[0024] 3.2 e max The value is compared with the judgment threshold E1 of the rotating rectifier failure:

[0025] When e max >E1, the rotating rectifier is judged to be faulty and step 4.1 is performed;

[0026] When emax When ≤E1, proceed to step 3.3;

[0027] 3.3 d max The value is compared with the judgment threshold D1 of the exciter rotor winding fault:

[0028] When max >D1, it is determined that the exciter rotor winding is faulty and proceed to step 4.2;

[0029] When max When ≤D1, proceed to step 3.4;

[0030] 3.4 m h The value is compared with the judgment threshold M2 of the short circuit fault of the main motor excitation winding:

[0031] When m h When ≤M2, it is judged that no fault has occurred;

[0032] When m h >M1, it is judged that the main motor excitation winding has a short circuit fault;

[0033] Step 4: When it is determined in step 3 that the exciter rotor winding or rotating rectifier fails, the fault type is identified and the fault point is located, specifically:

[0034] 4.1 When it is determined that the rotating rectifier has a fault, according to t min The fault type is determined by the relationship between the size of the threshold T1, and then the fault type is determined according to t min or max The fault point is located by the value of

[0035] (1) When t min When ≤T1, the rotating rectifier has an open circuit fault, and the fault location is:

[0036] When t min = t1, it is determined that the fault point is located at D1;

[0037] When t min = t2, it is determined that the fault point is located at D3;

[0038] When t min = t3, it is determined that the fault point is located at D5;

[0039] When t min = t4, it is determined that the fault point is located at D4;

[0040] When t min = t5, it is determined that the fault point is located at D6;

[0041] When t min= t6, it is determined that the fault point is located at D2;

[0042] (2) When t min When >T1, the rotating rectifier has a short circuit fault, and the fault location is:

[0043] When t max = t1, it is determined that the fault point is located at D4;

[0044] When t max = t2, it is determined that the fault point is located at D6;

[0045] When t max = t3, it is determined that the fault point is located at D2;

[0046] When t max = t4, it is determined that the fault point is located at D1;

[0047] When t max = t5, it is determined that the fault point is located at D3;

[0048] When t max = t6, it is determined that the fault point is located at D5;

[0049] The rotating rectifier is composed of 6 diodes, and the upper diode of the rotating rectifier phase A is marked as D1, and the lower diode is marked as D4, the upper diode of the B phase is marked as D3, and the lower diode is marked as D6, and the upper diode of the C phase is marked as D5, and the lower diode is marked as D2; and the current direction flowing from the exciter rotor winding into the rotating rectifier is specified as the positive direction;

[0050] 4.2 When it is determined that the exciter rotor winding is faulty, according to t min The fault type is judged according to the relationship between t min The fault point is located by the value of

[0051] (1) When t min When ≤T2, it is judged that the exciter rotor winding has an open circuit fault, and the fault location is:

[0052] When t min = t1 or t4, it is judged that the fault point is located in the A-phase winding of the exciter rotor;

[0053] When t min = t2 or t5, it is determined that the fault point is located in the B-phase winding of the exciter rotor;

[0054] When t min = t3 or t6, it is judged that the fault point is located in the C-phase winding of the exciter rotor;

[0055] (2) When t min >T2, it is determined that the exciter rotor winding has a short circuit fault, and the fault location is:

[0056] When t min = t1 or t4, it is judged that the fault point is located in the C-phase winding of the exciter rotor;

[0057] When t min = t2 or t5, it is judged that the fault point is located in the A-phase winding of the exciter rotor;

[0058] When t min = t3 or t6, it is determined that the fault point is located in the B-phase winding of the exciter rotor.

[0059] The rotating parts include the exciter rotor winding, the rotating rectifier and the main motor excitation winding. The exciter rotor winding includes three-phase windings A, B and C; the rotating rectifier is composed of 6 diodes, and the upper tube of the rotating rectifier A phase is marked as D1, the lower tube is marked as D4, the upper tube of the B phase is marked as D3, the lower tube is marked as D6, and the upper tube of the C phase is marked as D5, and the lower tube is marked as D2. It is stipulated that the direction of the current flowing from the exciter rotor winding into the rotating rectifier is the positive direction.

[0060] The electrical faults include open circuit faults and short circuit faults.

[0061] The stator voltage and current are collected through sensors.

[0062] The upper and lower envelopes of the rotor three-phase current are characterized by: t1 is the period i ar ≥i br And i ar ≥i cr The proportion of the time in a rotor current cycle; t2 is the ratio of i in a cycle br ≥i ar And i br ≥i cr The proportion of the time in a rotor current cycle; t3 is the ratio of i in a cycle cr ≥i ar And i cr ≥i br The proportion of the time in a rotor current cycle; t4 is the ratio of i in a cycle ar ≤i br And i ar ≤i cr The proportion of the time in a rotor current cycle; t5 is the ratio of i in a cycle br ≤i ar And i br ≤i cr The proportion of the time in a rotor current cycle; t6 is the ratio of i in a cycle cr ≤i ar And i cr ≤i br The ratio of the time to one rotor current cycle.

[0063] The value of the judgment threshold M1 for an open circuit fault of the main motor excitation winding is: 0 <M1≤8。

[0064] The value of the judgment threshold E1 of the rotating rectifier failure is: 0 <E1≤0.4。

[0065] The value of the judgment threshold D1 of the exciter rotor winding failure is: 0 <D1≤0.4。

[0066] The judgment threshold M2 of the main motor excitation winding short circuit fault is kU es , is a stator excitation voltage U es Proportional change in value, k>0.

[0067] The value of the judgment threshold T1 for judging whether the rotating rectifier has an open circuit fault or a short circuit fault is: 0 <T1≤0.2。

[0068] The value of the judgment threshold T2 for judging whether the exciter rotor winding has an open circuit fault or a short circuit fault is: 0 <T2≤0.2。

[0069] Beneficial Effects

[0070] The present invention proposes a method for diagnosing faults of rotating parts of a multi-stage starting system based on envelope attribution characteristics. The method first estimates the three-phase current of the exciter rotor, calculates the average value of the sum of the absolute values ​​of the three-phase current of the rotor, obtains the attribution time proportion of the upper and lower envelopes of the rotor three-phase current, and obtains the maximum value, minimum value, maximum difference of the same phase, maximum difference of the different phases and other characteristic quantities of the attribution time proportion, which are used for the diagnosis and positioning of electrical faults of rotating parts of the multi-stage starting system. The proposed method can diagnose online whether electrical faults occur in the rotating parts of the multi-stage starting system (including the exciter rotor winding, the rotating rectifier and the main motor excitation winding), and determine the fault type (open circuit fault or short circuit fault) and locate the specific position of the fault point. The method helps to make the multi-stage starting system more reliable and easier to maintain.

[0071] The present invention proposes an online diagnosis and location method for electrical faults of rotating components of a multi-stage starting system based on the attribution characteristics of the upper and lower envelopes of the three-phase current of the exciter rotor. The proposed method can diagnose online whether electrical faults occur in the rotating components of the multi-stage starting system (including the exciter rotor winding, the rotating rectifier and the main motor excitation winding), and at the same time determine the fault type and locate the specific location of the fault point. The method helps to improve the reliability of the operation of the multi-stage starting system and the convenience of maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 It is a schematic diagram of the structure of a typical multi-stage starting system;

[0073] Figure 2 It is a schematic diagram of the equivalent circuit of the rotor part of the multi-stage starting system;

[0074] Figure 3 The present invention provides a method for diagnosing and locating electrical faults of rotating parts;

[0075] Figure 4 This is a flow chart of the method for diagnosing and locating electrical faults of rotating parts proposed by the present invention;

[0076] Figure 5 is the characteristic quantity of the normal operation of the system (operating condition 1);

[0077] Figure 6 is the characteristic quantity of the exciter rotor winding phase B open circuit (operating condition 2);

[0078] Figure 7 is the characteristic quantity of the rotating rectifier D1 short circuit (operating condition 3);

[0079] Figure 8 It is the characteristic quantity of the main motor excitation winding open circuit (operating condition 4); DETAILED DESCRIPTION

[0080] The present invention will now be further described with reference to the embodiments and the accompanying drawings:

[0081] A method for online diagnosis and positioning of electrical faults in rotating parts of a multi-stage starting system based on the attribution characteristics of the upper and lower envelopes of the three-phase current of the exciter rotor. The rotating parts include the exciter rotor winding, the rotating rectifier and the main motor excitation winding. The exciter rotor winding includes three-phase windings A, B and C; the rotating rectifier is composed of 6 diodes, and the upper tube of the rotating rectifier A phase is marked as D1, the lower tube is marked as D4, the upper tube of the B phase is marked as D3, the lower tube is marked as D6, and the upper tube of the C phase is marked as D5, and the lower tube is marked as D2. The direction of the current flowing from the exciter rotor winding into the rotating rectifier is specified as the positive direction. The electrical faults include open circuit faults and short circuit faults.

[0082] Figure 3 The present invention provides a method for diagnosing and locating electrical faults of rotating parts; Figure 4 The present invention is further described below in conjunction with the accompanying drawings and embodiments, and the present invention includes but is not limited to the following embodiments.

[0083] In the embodiment, a multi-stage starting system simulation model is established, such as Figure 1 As shown in the figure, the stator excitation winding of the exciter used is a two-phase winding. During the operation of the system, assume that the current direction flowing from the exciter rotor winding into the rotating rectifier is positive, the motor speed is 100r / min, and the exciter stator excitation voltage amplitude is 100V, that is, U es=100V, the frequency is 110Hz, and the frequency of the exciter rotor current is 100Hz. The fault diagnosis and positioning method is described by taking the rotating parts without electrical fault (operating condition 1), the exciter rotor winding B phase open circuit (operating condition 2), the rotating rectifier A phase upper tube (D1) short circuit (operating condition 3), and the main motor excitation winding open circuit fault (operating condition 4) as examples. The specific steps included in the embodiment are as follows:

[0084] Step 1: Collect the stator voltage and current of the exciter through the sensor, and estimate the three-phase current of the exciter rotor according to the voltage equation and flux equation of the exciter, which is recorded as i ar 、i br 、i cr .

[0085] Step 2: Process the estimated rotor three-phase current to obtain characteristic quantities.

[0086] 2.1 Calculate the sum of the absolute values ​​of the three-phase current of the rotor, denoted as i h ,i h =|i ar |+|i br |+|i cr |. According to the exciter rotor current frequency, the sliding window mode is used to calculate the i within one cycle h The average value of

[0087] The frequency of the rotor current is 100Hz, and the sampling frequency is 100kHz, then The number of sampling points in one current cycle Based on this, moving window sampling is performed to calculate i in a period T in real time h The average value, denoted as m h .

[0088] 2.2 Obtain the attribution characteristics of the upper and lower envelopes of the rotor three-phase current:

[0089] Let t1 be the i ar ≥i br And i ar ≥i cr The proportion of the time to a rotor current cycle;

[0090] t2 is the period i br ≥i ar And i br ≥i cr The proportion of the time to a rotor current cycle;

[0091] t3 is the period i cr ≥i ar And i cr ≥i brThe proportion of the time to a rotor current cycle;

[0092] t4 is the period i ar ≤i br And i ar ≤i cr The proportion of the time to a rotor current cycle;

[0093] t5 is the period i br ≤i ar And i br ≤i cr The proportion of the time to a rotor current cycle;

[0094] t6 is the period i cr ≤i ar And i cr ≤i br The ratio of the time to one rotor current cycle.

[0095] 2.3 Calculate the maximum difference in the time proportion of the upper and lower envelopes of the rotor three-phase current, recorded as e max , e max =max{|t1-t4|,|t2-t5|,|t3-t6|}.

[0096] 2.4 Calculate the maximum difference in the time proportion of the upper and lower envelopes of the rotor three-phase current, recorded as d max , d max =max{|t1-t2|,|t2-t3|,|t3-t1|,|t4-t5|,|t5-t6|,|t6-t4|}.

[0097] 2.5 Calculate the minimum value of the time proportion of the upper and lower envelopes of the rotor three-phase current, recorded as t min , t min =min{t1,t2,t3,t4,t5,t6}.

[0098] 2.6 Calculate the maximum value of the time proportion of the upper and lower envelopes of the rotor three-phase current, recorded as t max , t max =max{t1,t2,t3,t4,t5,t6}.

[0099] The above steps can be used to obtain the fault diagnosis feature quantity. The simulation results are shown in Table 1 and Figure 5-Figure 8 As shown:

[0100] Table 1: Results of three-phase current preprocessing characteristic values ​​of the exciter rotor in the embodiment

[0101] Working conditions <![CDATA[m h ]]> <![CDATA[t1]]> <![CDATA[t2]]> <![CDATA[t3]]> <![CDATA[t4]]> <![CDATA[t5]]> <![CDATA[t6]]> <![CDATA[e max ]]> <![CDATA[d max ]]> <![CDATA[t min ]]> <![CDATA[t max ]]> 1 27.6 0.33 0.33 0.33 0.33 0.33 0.33 0.00 0.00 0.33 0.33 2 15.5 0.50 0.00 0.50 0.50 0.00 0.50 0.00 0.50 0.00 0.50 3 51.8 0.32 0.34 0.34 0.57 0.20 0.23 0.25 0.37 0.20 0.57 4 0.3 - - - -- - - - - - -

[0102] Step 3: Perform electrical fault diagnosis on the rotating components based on the characteristic quantities obtained in Step 2 to identify the faulty components, specifically as follows:

[0103] 3.1 Based on the magnitude relationship between the value of m h and the threshold M1, perform open - circuit fault diagnosis on the main motor excitation winding. The threshold M1 is the judgment threshold for the occurrence of an open - circuit fault in the main motor excitation winding, where 0 < M1 ≤ 8 and is determined according to the actual application object. In the embodiment, the threshold M1 takes the value of 5. Specifically:

[0104] Condition 1: m h = 27.6, m h > 5, proceed to step (3.2).

[0105] Condition 2: m h = 15.5, m h > 5, proceed to step (3.2).

[0106] Condition 3: m h = 51.8, m h > 5, proceed to step (3.2).

[0107] Condition 4: m h = 0.3, m h ≤ 5, judge that an open - circuit fault has occurred in the main motor excitation winding.

[0108] 3.2 Based on the magnitude relationship between the value of e max and the threshold E1, perform rotating rectifier fault diagnosis. The threshold E1 is the judgment threshold for the occurrence of a fault in the rotating rectifier, where 0 < E1 ≤ 0.4 and is determined according to the actual application object. In the embodiment, the threshold E1 takes the value of 0.1. Specifically:

[0109] Condition 1: e max = 0.00, e max ≤ 0.1, proceed to step (3.3).

[0110] Condition 2: e max = 0.00, e max ≤ 0.1, proceed to step (3.3).

[0111] Condition 3: e max = 0.50, e max > 0.1, judge that the rotating rectifier has a fault and proceed to step (4.1).

[0112] 3.3 Based on the magnitude relationship between the value of d max and the threshold D1, perform exciter rotor winding fault diagnosis. The threshold D1 is the judgment threshold for the occurrence of a fault in the exciter rotor winding, where 0 < D1 ≤ 0.4 and is determined according to the actual application object. In the embodiment, the threshold D1 takes a positive value close to 0. Specifically:

[0113] Operating condition 1: d max = 0.00, d max ≤ 0.1, perform step (3.4).

[0114] Operating condition 2: d max = 0.50, d max > 0.1, determine that the exciter rotor winding has a fault, and perform step (4.2).

[0115] 3.4 According to the magnitude relationship between the value of m h and the threshold M2, perform the short - circuit fault diagnosis of the main motor excitation winding. The threshold M2 is the judgment threshold for the short - circuit fault of the main motor excitation winding, and the threshold M2 = kU es , which is a value that changes proportionally with the stator excitation voltage U es of the exciter. k > 0 and needs to be determined according to the actual application object. In the embodiment, k = 0.5, and the threshold M2 = kU es = 0.5×100 = 50, specifically:

[0116] (1) When m h ≤ M2, determine that no fault has occurred.

[0117] (2) When m h > M1, determine that the main motor excitation winding has a short - circuit fault.

[0118] Embodiment, operating condition 1: m h = 27.6, m h ≤ 50, determine that no fault has occurred.

[0119] Step 4: After determining that the exciter rotor winding or the rotating rectifier has a fault in step 3, perform fault type discrimination and fault point location, specifically:

[0120] 4.1 After determining that the rotating rectifier has a fault, perform fault type discrimination according to the magnitude relationship between t min and the threshold T1. The threshold T1 is the judgment threshold for discriminating between an open - circuit fault or a short - circuit fault of the rotating rectifier, 0 < T1 ≤ 0.2, and is determined according to the actual application object; in the embodiment, the threshold T1 is taken as 0.1, and perform fault point location according to the value of t min or t max :

[0121] (1) When t min ≤ T1, determine that the rotating rectifier has an open - circuit fault.

[0122] A. When t min = t1, determine that the fault point is located at D1.

[0123] B. When tmin = t2, it is determined that the fault point is located at D3.

[0124] C. When t min = t3, it is determined that the fault point is located at D5.

[0125] D. When t min = t4, it is determined that the fault point is located at D4.

[0126] E. When t min = t5, it is determined that the fault point is located at D6.

[0127] F. When t min = t6, it is determined that the fault point is located at D2.

[0128] (2) When t min >T1, it is determined that a short circuit fault occurs in the rotating rectifier.

[0129] A. When t max = t1, it is determined that the fault point is located at D4.

[0130] B. When t max = t2, it is determined that the fault point is located at D6.

[0131] C. When t max = t3, it is determined that the fault point is located at D2.

[0132] D. When t max = t4, it is determined that the fault point is located at D1.

[0133] E. When t max = t5, it is determined that the fault point is located at D3.

[0134] F. When t max = t6, it is determined that the fault point is located at D5.

[0135] The specific embodiment is: Working condition 3: t min =0.20, t min >0.1, it is judged that the rotating rectifier has a short circuit fault. max =t4, it is determined that the fault point is located at D1.

[0136] 4.2 When it is determined that the exciter rotor winding is faulty, according to t min The fault type is judged by the relationship between the size of the threshold value T2. The threshold value T2 is the judgment threshold for judging whether the exciter rotor winding has an open circuit fault or a short circuit fault. 0<T2≤0.2, and it is determined according to the actual application object; the threshold value T2 is 0.1, according to t min The fault point is located by the value of

[0137] (1) When tmin When ≤T2, it is determined that an open circuit fault occurs in the exciter rotor winding.

[0138] A. When t min = t1 or t4, it is determined that the fault point is located in the A-phase winding of the exciter rotor.

[0139] B. When t min = t2 or t5, it is determined that the fault point is located in the B-phase winding of the exciter rotor.

[0140] C. When t min = t3 or t6, it is determined that the fault point is located in the C-phase winding of the exciter rotor.

[0141] (2) When t min When >T2, it is determined that a short circuit fault occurs in the exciter rotor winding.

[0142] A. When t min = t1 or t4, it is determined that the fault point is located in the C-phase winding of the exciter rotor.

[0143] B. When t min = t2 or t5, it is determined that the fault point is located in the A-phase winding of the exciter rotor.

[0144] C. When t min = t3 or t6, it is determined that the fault point is located in the B-phase winding of the exciter rotor.

[0145] Example Condition 2: t min =0.00, t min ≤0.1, it is judged that the exciter rotor winding has an open circuit fault. min =t2, it is determined that the fault point is located in the B phase winding.

[0146] According to the embodiments, the present invention proposes an online diagnosis and location method for electrical faults of rotating parts of a multi-stage starting system based on the attribution characteristics of the upper and lower envelopes of the three-phase current of the exciter rotor, which can diagnose online whether electrical faults occur in the rotating parts of the multi-stage starting system (including the exciter rotor winding, the rotating rectifier and the main motor excitation winding), and at the same time determine the fault type and locate the specific position of the fault point. This method helps to improve the reliability of the operation of the multi-stage starting system and the convenience of maintenance.

Claims

1. A method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics, characterized in that Here are the steps: Step 1: Based on the collected stator voltage and current of the exciter, estimate the three-phase current of the exciter rotor according to the voltage equation and flux equation of the exciter, denoted as i ar 、i br 、i cr ; Step 2: Process the rotor three-phase current to obtain characteristic quantities; The feature quantities include: The sum of the absolute values ​​of the three-phase currents of the rotor in one cycle is i h The average value m h : The sum of the absolute values ​​of the three-phase current of the rotor i h =|i ar |+|i br |+|i cr |, using the sliding window mode to calculate the i within a cycle h The average value m h ; The maximum difference in the time proportion of the upper and lower envelopes of the rotor three-phase current e max :e max =max{|t1-t4|, |t2-t5|, |t3-t6|}; The maximum difference d between the time proportions of the upper and lower envelopes of the rotor three-phase current max :d max =max{|t1-t2|, |t2-t3|, |t3-t1|, |t4-t5|, |t5-t6|, |t6-t4|}; The minimum value t of the time proportion of the upper and lower envelopes of the rotor three-phase current min :t min =min{t1, t2, t3, t4, t5, t6}; The maximum value t of the time proportion of the upper and lower envelopes of the rotor three-phase current max :t max =max{t1, t2, t3, t4, t5, t6}; The t1, t2, t3, t4, t5, and t6 are the attribution characteristics of the upper and lower envelopes of the rotor three-phase current; Step 3: Perform electrical fault diagnosis of rotating components based on characteristic quantities and identify faulty components: 3.1: m h The value is compared with the judgment threshold M1 of the open circuit fault of the main motor excitation winding: When m h When ≤M1, it is judged that the main motor excitation winding has an open circuit fault; When m h >M1, proceed to step 3.2; 3.2 e max The value is compared with the judgment threshold E1 of the rotating rectifier failure: when e max >E1, it is determined that the rotating rectifier is faulty and proceed to step 4.1; when e max When ≤E1, proceed to step 3.3; 3.3 d max The value is compared with the judgment threshold D1 of the exciter rotor winding fault: When max >D1, it is determined that the exciter rotor winding is faulty and the step 4.2 is performed; When max When ≤D1, proceed to step 3.4; 3.4 m h The value is compared with the judgment threshold M2 of the short circuit fault of the main motor excitation winding: When m h When ≤M2, it is judged that no fault has occurred; When m h >M1, it is judged that the main motor excitation winding has a short circuit fault; Step 4: When it is determined in step 3 that the exciter rotor winding or rotating rectifier fails, the fault type is identified and the fault point is located, specifically: 4.1 When it is determined that the rotating rectifier has a fault, according to t min The fault type is determined by the relationship between the size of the threshold T1, and then the fault type is determined according to t min or max The fault point is located by the value of (1) When t min When ≤T1, the rotating rectifier has an open circuit fault, and the fault location is: When t min = t1, it is determined that the fault point is located at D1; When t min = t2, it is determined that the fault point is located at D3; When t min = t3, it is determined that the fault point is located at D5; When t min = t4, it is determined that the fault point is located at D4; When t min = t5, it is determined that the fault point is located at D6; When t min = t6, it is determined that the fault point is located at D2; (2) When t min >T1, a short circuit fault occurs in the rotating rectifier, and the fault location is: When t max = t1, it is determined that the fault point is located at D4; When t max = t2, it is determined that the fault point is located at D6; When t max = t3, it is determined that the fault point is located at D2; When t max = t4, it is determined that the fault point is located at D1; When t max = t5, it is determined that the fault point is located at D3; When t max = t6, it is determined that the fault point is located at D5; The rotating rectifier is composed of 6 diodes, and the upper diode of the rotating rectifier phase A is marked as D1, and the lower diode is marked as D4, the upper diode of the B phase is marked as D3, and the lower diode is marked as D6, and the upper diode of the C phase is marked as D5, and the lower diode is marked as D2; and the current direction flowing from the exciter rotor winding into the rotating rectifier is specified as the positive direction; 4.2 When it is determined that the exciter rotor winding is faulty, according to t min The fault type is judged according to the relationship between t min The fault point is located by the value of (1) When t min When ≤T2, it is judged that the exciter rotor winding has an open circuit fault, and the fault location is: When t min = t1 or t4, it is judged that the fault point is located in the A-phase winding of the exciter rotor; When t min = t2 or t5, it is determined that the fault point is located in the B-phase winding of the exciter rotor; When t min = t3 or t6, it is judged that the fault point is located in the C-phase winding of the exciter rotor; (2) When t min >T2, it is determined that the exciter rotor winding has a short circuit fault, and the fault location is: When t min = t1 or t4, it is judged that the fault point is located in the C-phase winding of the exciter rotor; When t min = t2 or t5, it is judged that the fault point is located in the A-phase winding of the exciter rotor; When t min = t3 or t6, it is determined that the fault point is located in the B-phase winding of the exciter rotor. The rotating parts include the exciter rotor winding, the rotating rectifier and the main motor excitation winding. The exciter rotor winding includes three-phase windings A, B and C; the rotating rectifier is composed of 6 diodes, and the upper tube of the rotating rectifier A phase is marked as D1, the lower tube is marked as D4, the upper tube of the B phase is marked as D3, the lower tube is marked as D6, and the upper tube of the C phase is marked as D5, and the lower tube is marked as D2. It is stipulated that the direction of the current flowing from the exciter rotor winding into the rotating rectifier is the positive direction.

2. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1 is characterized in that: The electrical faults include open circuit faults and short circuit faults.

3. The multi-stage starting system rotating component fault diagnosis method based on envelope attribution characteristics according to claim 1 is characterized in that: The stator voltage and current are collected through sensors.

4. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The rotor three-phase current upper and lower envelopes are characterized by: t1 is the period i ar ≥i br And i ar ≥i cr The proportion of the time in a rotor current cycle; t2 is the ratio of i in a cycle br ≥i ar And i br ≥i cr The proportion of the time in a rotor current cycle; t3 is the ratio of i in a cycle cr ≥i ar And i cr ≥i br The proportion of the time occupied by a rotor current cycle; t4 is the period i ar ≤i br And i ar ≤i cr The proportion of the time occupied by a rotor current cycle; t5 is the period i br ≤i ar And i br ≤i cr The proportion of the time in a rotor current cycle; t6 is the ratio of i in a cycle cr ≤i ar And i cr ≤i br The ratio of the time to one rotor current cycle.

5. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The value of the judgment threshold M1 for an open circuit fault of the main motor excitation winding is: 0 <M1≤8。 6. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The value of the judgment threshold E1 of the rotating rectifier failure is: 0 <E1≤0.4。 7. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The value of the judgment threshold D1 of the exciter rotor winding failure is: 0< D1≤0.4。 8. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The judgment threshold M2 of the main motor excitation winding short circuit fault is kU es , is a stator excitation voltage U es Proportional change in value, k>0.

9. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The value of the judgment threshold T1 for judging whether the rotating rectifier has an open circuit fault or a short circuit fault is: 0 <T1≤0.2。 10. The method for diagnosing faults of rotating components of a multi-stage starting system based on envelope attribution characteristics according to claim 1, characterized in that: The value of the judgment threshold T2 for judging whether the exciter rotor winding has an open circuit fault or a short circuit fault is: 0 <D2≤0.2。

Images