Method and device for evaluating insulation to ground of fan driving motor

Abstract

The invention discloses a fan driving motor ground insulation evaluation method and device, and the method comprises the steps: inputting an effective value of a common-mode leakage current signal of a fan driving motor into a constructed fan driving motor ground insulation impedance evaluation model 1, and obtaining a first evaluation result; inputting a vibration speed signal of the fan driving motor into the constructed fan driving motor ground insulation impedance evaluation model 2 to obtain a second evaluation result; inputting the first evaluation result and the second evaluation result into a constructed fan driving motor ground insulation impedance fusion evaluation model to obtain a third evaluation result; and inputting the third evaluation result and a corresponding principal component obtained by the AC voltage signal into a constructed fan driving motor ground insulation decoupling model to obtain the resistance value of a fan driving motor ground insulation resistor and the capacitance value of a fan driving motor ground insulation capacitor. According to the invention, on-line monitoring of the ground insulation of the driving motor of the cooling tower fan of the phase modifier is realized, and the detection precision of the ground insulation of the driving motor of the cooling tower fan of the phase modifier is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor insulation detection, and in particular relates to a method and a device for evaluating the insulation of a fan drive motor to the ground. Background Art

[0002] The fan drive motor of a condenser cooling tower is a common auxiliary motor of a condenser system. The working conditions, including inverter power supply and industrial frequency power supply, have an important impact on the safe and stable operation of the condenser system. The current insulation detection method of the fan drive motor of a condenser cooling tower is mainly offline detection through insulation megger, insulation resistance tester, etc. The disadvantages of offline detection are: (1) It has limitations in real-time performance and labor cost; (2) The detection cycle is long, and it is difficult to reflect the insulation aging process of the fan drive motor of the condenser cooling tower. Summary of the invention

[0003] In order to solve the deficiencies in the prior art, the present invention provides a method and device for evaluating the insulation of a fan drive motor to the ground, which can realize online monitoring of the insulation of a fan drive motor to the ground in a phase-shifting cooling tower, and at the same time improve the detection accuracy of the insulation of the fan drive motor to the ground in a phase-shifting cooling tower.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: In a first aspect, a method for evaluating the insulation of a fan drive motor to ground is provided, comprising: collecting a vibration velocity signal, a common-mode leakage current signal and an AC voltage signal of the fan drive motor; obtaining an effective value of the common-mode leakage current signal of the fan drive motor according to the common-mode leakage current signal of the fan drive motor, and inputting the effective value of the common-mode leakage current signal of the fan drive motor into a constructed fan drive motor insulation impedance evaluation model 1 to obtain a first evaluation result; inputting the vibration velocity signal of the fan drive motor into a constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; inputting the first evaluation result and the second evaluation result into a constructed fan drive motor insulation impedance fusion evaluation model to obtain a third evaluation result; inputting the third evaluation result and the corresponding principal component obtained from the AC voltage signal into a constructed fan drive motor insulation decoupling model to obtain the resistance value of the fan drive motor insulation resistance to ground and the capacitance value of the ground insulation capacitance to ground.

[0005] Furthermore, taking the effective value of the common-mode leakage current signal of the fan drive motor as input and the modulus of the insulation impedance of the fan drive motor to the ground as output, the extreme learning machine is trained through the constructed fan drive motor to ground insulation fault sample set to obtain the first fan drive motor to ground insulation impedance evaluation model; taking the vibration speed signal of the fan drive motor as input and the modulus of the insulation impedance of the fan drive motor to the ground as output, the extreme learning machine is trained through the constructed fan drive motor to ground insulation fault sample set to obtain the second fan drive motor to ground insulation impedance evaluation model; the correlation analysis is performed on the effective value of the common-mode leakage current signal of the fan drive motor and the modulus of the insulation impedance of the fan drive motor to the ground through the constructed fan drive motor to ground insulation fault sample set to obtain the first a correlation coefficient; a correlation analysis is performed on the vibration velocity signal of the fan drive motor and the modulus of the fan drive motor insulation impedance to the ground through the constructed fan drive motor insulation fault sample set to obtain a second correlation coefficient; a fan drive motor insulation impedance fusion evaluation model is established for linearly weighted fusion of the first evaluation result and the second evaluation result according to the first correlation coefficient and the second correlation coefficient; the modulus of the fan drive motor insulation impedance and the main component of the AC voltage signal after amplification and DC bias are taken as input, and the resistance value of the fan drive motor insulation resistance to the ground and the capacitance value of the ground insulation capacitor are taken as output, and an extreme learning machine is trained through the constructed fan drive motor insulation fault sample set to obtain a fan drive motor insulation decoupling model.

[0006] Furthermore, a method for constructing a sample set of ground insulation faults of a fan drive motor includes: setting different ground insulation faults in a certain phase of the fan drive motor stator, wherein the ground insulation fault is formed by a group of parallel ground insulation resistors and ground insulation capacitors, and different ground insulation faults occur when the resistance value of the ground insulation resistor or the capacitance value of the ground insulation capacitor is different; when a certain ground insulation fault is set, the common-mode leakage current signal of the fan drive motor is collected, and the corresponding AC voltage signal is output, and then the signal is amplified through an instrument amplifier circuit, and then divided into two paths, one of which is amplified by an effective value circuit and a restoration operation in a DSP to obtain the effective value of the common-mode leakage current signal of the fan drive motor, and the other amplified AC voltage signal is passed through a DC bias circuit, and then discrete Fourier transform and principal component analysis are performed to obtain the amplitude of the AC voltage signal of several set frequencies, and the vibration speed of the fan drive motor is obtained. degree signal, thereby forming a fan drive motor insulation fault sample to ground, wherein the input of the fan drive motor insulation fault sample includes the effective value of the fan drive motor common mode leakage current signal, the fan drive motor vibration speed signal, and the AC voltage signal amplitude of several set frequencies, and the output of the fan drive motor insulation fault sample includes the resistance of the fan drive motor insulation resistance to ground, the capacitance of the ground insulation capacitor, and the modulus of the ground insulation impedance; different fan drive motor insulation fault samples are obtained by setting different ground insulation faults to form an initial ground insulation fault sample set; principal component analysis is performed on the amplitude parts of different frequencies in each sample input of the initial ground insulation fault sample set, and the number of extracted components k is determined according to the set extraction conditions, and then the first k components are used to replace the amplitude parts of different frequencies in the sample input of the initial ground insulation fault sample set, thereby obtaining the fan drive motor insulation fault sample set.

[0007] Furthermore, the common-mode leakage current signal of the fan drive motor is collected by a zero-flux leakage current sensor; and the vibration speed signal of the fan drive motor is obtained by a vibration speed sensor.

[0008] Furthermore, the set extraction conditions include: the percentage of explained variance to total variance is greater than 90%.

[0009] Furthermore, the first correlation coefficient and the second correlation coefficient are both Pearson correlation coefficients, and the calculation method is: , , Among them, the first correlation coefficient is the Pearson correlation coefficient between the effective value of the common-mode leakage current signal of the fan drive motor and the mode of the insulation impedance of the fan drive motor to the ground; the second correlation coefficient is the Pearson correlation coefficient between the vibration speed signal of the fan drive motor and the module of the insulation impedance of the fan drive motor to ground; The number of samples in the fan drive motor ground insulation fault sample set; This is the first sample of the fan drive motor insulation fault sample. The effective value of the fan drive motor common mode leakage current signal in the input of samples, ; This is the first sample of the fan drive motor insulation fault sample. The vibration speed signal of the fan drive motor in the input of samples; This is the first sample of the fan drive motor insulation fault sample. The model of the insulation impedance of the fan drive motor to ground in the output of each sample; is the mean value of the effective value of the common mode leakage current signal of each sample fan drive motor in the fan drive motor insulation fault sample set; is the mean value of the vibration speed signal of each sample fan drive motor in the fan drive motor insulation fault sample set; It is the mean value of the module of the insulation impedance of each fan drive motor to ground in the fan drive motor to ground insulation fault sample set.

[0010] Furthermore, the insulation impedance fusion evaluation model of the fan drive motor to ground is: , in, A first evaluation result output by a first evaluation model for evaluating the insulation impedance of a fan drive motor to ground; is a second evaluation result output by the second wind turbine drive motor insulation impedance evaluation model; It is the third evaluation result output by the fusion evaluation model of the insulation impedance of the wind turbine drive motor to the ground.

[0011] Furthermore, the method for obtaining the corresponding principal components obtained from the AC voltage signal includes: amplifying the AC voltage signal, DC biasing, and then performing a discrete Fourier transform to obtain the amplitudes of different frequencies, and then combining the principal component analysis results when constructing the fan drive motor to ground insulation fault sample set, converting the discrete Fourier transform results to obtain the corresponding principal components.

[0012] In a second aspect, a device for evaluating the insulation of a fan drive motor to ground is provided, comprising: a data acquisition module for acquiring a vibration velocity signal, a common-mode leakage current signal and an AC voltage signal of the fan drive motor; a common-mode leakage current evaluation module for obtaining an effective value of the common-mode leakage current signal of the fan drive motor according to the common-mode leakage current signal of the fan drive motor, and inputting the effective value of the common-mode leakage current signal of the fan drive motor into a constructed fan drive motor insulation impedance evaluation model 1 to obtain a first evaluation result; a vibration velocity evaluation module for inputting the vibration velocity signal of the fan drive motor into a constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; a fusion evaluation module for inputting the first evaluation result and the second evaluation result into a constructed fan drive motor insulation impedance fusion evaluation model to obtain a third evaluation result; and a ground insulation evaluation module for inputting the third evaluation result and the corresponding principal component obtained from the AC voltage signal into a constructed fan drive motor insulation decoupling model to obtain the resistance value of the fan drive motor insulation resistance and the capacitance value of the ground insulation capacitance.

[0013] In a third aspect, a computer device / equipment / system is provided, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method for evaluating the insulation of a fan drive motor to the ground as described in the first aspect.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention inputs the effective value of the common-mode leakage current signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 1 to obtain a first evaluation result; inputs the vibration speed signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; inputs the first evaluation result and the second evaluation result into the constructed fan drive motor insulation impedance fusion evaluation model to obtain a third evaluation result; inputs the third evaluation result and the corresponding principal component obtained by the AC voltage signal into the constructed fan drive motor insulation decoupling model to obtain the resistance value of the fan drive motor insulation resistance to ground and the capacitance value of the ground insulation capacitance to ground; realizes online monitoring of the insulation of the fan drive motor of the phase-shifting cooling tower to ground, and at the same time improves the detection accuracy of the insulation of the fan drive motor of the phase-shifting cooling tower to ground. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the principle of a method for evaluating the insulation of a fan drive motor to the ground provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0017] Embodiment 1 A method for evaluating the insulation of a fan drive motor to ground, comprising: collecting a vibration velocity signal, a common-mode leakage current signal and an alternating current voltage signal of the fan drive motor; obtaining an effective value of the common-mode leakage current signal of the fan drive motor according to the common-mode leakage current signal of the fan drive motor, and inputting the effective value of the common-mode leakage current signal of the fan drive motor into a constructed fan drive motor insulation impedance evaluation model 1 to obtain a first evaluation result; inputting the vibration velocity signal of the fan drive motor into a constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; inputting the first evaluation result and the second evaluation result into a constructed fan drive motor insulation impedance fusion evaluation model to obtain a third evaluation result; inputting the third evaluation result and the corresponding principal component obtained from the alternating current voltage signal into a constructed fan drive motor insulation decoupling model to obtain the resistance value of the fan drive motor insulation resistance to ground and the capacitance value of the ground insulation capacitance to ground.

[0018] The present invention takes the process of detecting the insulation of a fan drive motor of a phase-shifting cooling tower to the ground as an example, and further describes the establishment process of each model in the present invention and the method for detecting the insulation of the fan drive motor to the ground as follows.

[0019] like Figure 1 As shown, the present invention provides a modeling method for evaluating the insulation of a fan drive motor to ground in a phase-shifting cooling tower based on information fusion, including: constructing a sample set of insulation faults of a fan drive motor to ground, establishing a first evaluation model of insulation impedance of a fan drive motor to ground based on the effective value of a common-mode leakage current signal, establishing a second evaluation model of insulation impedance of a fan drive motor to ground based on a vibration velocity signal, establishing a decoupling model of insulation of a fan drive motor to ground, establishing a fusion evaluation model of insulation impedance of a fan drive motor to ground, and a method for evaluating the insulation of a fan drive motor to ground based on the established evaluation models.

[0020] A method for constructing a sample set of ground insulation faults of a fan drive motor includes: setting different ground insulation faults in a certain phase of a stator of the fan drive motor, wherein the ground insulation faults are formed by a group of parallel ground insulation resistors and ground insulation capacitors, and different ground insulation faults are formed when the resistance value of the ground insulation resistor or the capacitance value of the ground insulation capacitor is different.

[0021] When a certain ground insulation fault is set for the fan drive motor powered by the inverter, the zero flux leakage current sensor is used to collect the common mode leakage current signal of the fan drive motor, and the corresponding AC voltage signal is output. The signal is then amplified by the instrument amplifier circuit. At this time, it is divided into two paths. The amplified AC voltage signal on one path passes through the effective value circuit and the restoration operation in the DSP to obtain the effective value of the common mode leakage current signal of the fan drive motor. The amplified AC voltage signal on the other path passes through the DC bias circuit and then undergoes discrete Fourier transform to obtain several set frequencies (such as 0, 1, 2, 3, ..., 5 0,…,150,…,350Hz, etc.), and obtain the vibration speed signal of the fan drive motor through the vibration speed sensor, so as to form a fan drive motor to ground insulation fault sample, wherein the input of the fan drive motor to ground insulation fault sample includes the effective value of the fan drive motor common mode leakage current signal, the vibration speed signal of the fan drive motor, and the AC voltage signal amplitudes of several set frequencies; the output of the fan drive motor to ground insulation fault sample includes the resistance value of the fan drive motor to ground insulation resistance, the capacitance value of the ground insulation capacitance, and the mode value of the ground insulation impedance.

[0022] Different ground insulation fault samples of the fan drive motor are obtained by setting different ground insulation faults to form an initial ground insulation fault sample set.

[0023] A principal component analysis is performed on the amplitude parts of different frequencies in each sample input of the initial ground insulation fault sample set, and the number of extracted components k is determined according to the set extraction conditions (the extraction conditions set in the present invention are: the percentage of explained variance to total variance is greater than 90%), and then the first k components are used to replace the amplitude parts of different frequencies in the sample input of the initial ground insulation fault sample set, so as to obtain the final fan drive motor ground insulation fault sample set.

[0024] The establishment of the wind turbine drive motor insulation impedance to ground evaluation model 1 based on the effective value of the common-mode leakage current signal is based on the above-mentioned final wind turbine drive motor insulation fault sample set, combined with the extreme learning machine (ELM), the effective value of the common-mode leakage current signal in the sample input of the sample set is used as the input of the ELM, and the mode of the wind turbine drive motor insulation impedance to ground in the sample output of the sample set is used as the output of the ELM, and the extreme learning machine model is trained, thereby establishing the wind turbine drive motor insulation impedance to ground evaluation model 1 (ELM1) based on the effective value of the common-mode leakage current signal.

[0025] The establishment of the second wind turbine drive motor insulation impedance assessment model based on vibration velocity signal is based on the above-mentioned final wind turbine drive motor insulation fault sample set, combined with ELM, the vibration velocity signal of the wind turbine drive motor in the sample input of the sample set is used as the input of ELM, and the model of the wind turbine drive motor insulation impedance in the sample output of the sample set is used as the output of ELM, and the ELM model is trained, thereby establishing the second wind turbine drive motor insulation impedance assessment model based on vibration velocity signal (ELM2).

[0026] The establishment of the fan drive motor to ground insulation decoupling model is based on the above-mentioned final fan drive motor to ground insulation fault sample set, combined with ELM, the model of the fan drive motor to ground insulation impedance, the main component of the AC voltage signal after amplification and DC bias is used as input, and the resistance of the fan drive motor to ground insulation resistance and the capacitance of the ground insulation capacitor are used as outputs to train the ELM model, thereby establishing the fan drive motor to ground insulation decoupling model (ELM3).

[0027] The establishment of the fusion evaluation model of the insulation impedance of the fan drive motor to the ground is based on the above-mentioned final sample set. The correlation analysis is performed on the effective value of the common-mode leakage current signal of the fan drive motor and the mode of the insulation impedance of the fan drive motor to the ground to obtain the first correlation coefficient; the correlation analysis is performed on the vibration speed signal of the fan drive motor and the mode of the insulation impedance of the fan drive motor to the ground to obtain the second correlation coefficient.

[0028] The first correlation coefficient and the second correlation coefficient are both Pearson correlation coefficients, and the calculation method is: , , Among them, the first correlation coefficient is the Pearson correlation coefficient between the effective value of the common-mode leakage current signal of the fan drive motor and the mode of the insulation impedance of the fan drive motor to the ground; the second correlation coefficient is the Pearson correlation coefficient between the vibration speed signal of the fan drive motor and the module of the insulation impedance of the fan drive motor to ground; The number of samples in the fan drive motor ground insulation fault sample set; This is the first sample of the fan drive motor insulation fault sample. The effective value of the fan drive motor common mode leakage current signal in the input of samples, ; This is the first sample of the fan drive motor insulation fault sample. The vibration speed signal of the fan drive motor in the input of samples; This is the first sample of the fan drive motor insulation fault sample. The model of the insulation impedance of the fan drive motor to ground in the output of each sample; is the mean value of the effective value of the common mode leakage current signal of each sample fan drive motor in the fan drive motor insulation fault sample set; is the mean value of the vibration speed signal of each sample fan drive motor in the fan drive motor insulation fault sample set; It is the mean value of the module of the insulation impedance of each fan drive motor to ground in the fan drive motor to ground insulation fault sample set.

[0029] In the calculation , Then, according to the absolute values ​​of the two correlation coefficients, a fusion evaluation model of the insulation impedance of the fan drive motor to the ground is established by linearly weighted fusion of the evaluation results of ELM1 and ELM2. The specific calculation method is expressed by the following formula: , in, A first evaluation result output by a first evaluation model for evaluating the insulation impedance of a fan drive motor to ground; is a second evaluation result output by the second wind turbine drive motor insulation impedance evaluation model; It is the third evaluation result output by the fusion evaluation model of the insulation impedance of the wind turbine drive motor to the ground.

[0030] like Figure 1As shown, the method for evaluating the insulation of a fan drive motor to ground based on each established evaluation model includes: collecting the common-mode leakage current signal of the fan drive motor through a zero-flux leakage current sensor, and outputting a corresponding AC voltage signal, and then amplifying the signal through an instrument amplifier circuit. At this time, it is divided into two paths. The amplified AC voltage signal on one path passes through an effective value circuit and a restoration operation in a DSP to obtain the effective value of the common-mode leakage current signal of the fan drive motor, and then the effective value of the common-mode leakage current signal of the fan drive motor and the established ELM1 are used to obtain the insulation impedance evaluation result of the fan drive motor to ground (the first evaluation result), and the amplified AC voltage signal on the other path passes through a DC bias circuit, and then a discrete Fourier transform is performed to obtain amplitudes of different frequencies, and then combined with the principal component analysis result when constructing the fan drive motor insulation fault sample set, the discrete Fourier transform result at this time is converted to obtain the corresponding principal component (the corresponding principal component obtained from the AC voltage signal). The vibration velocity signal of the fan drive motor is obtained by a vibration velocity sensor, and then another fan drive motor insulation impedance evaluation result (second evaluation result) is obtained by the vibration velocity signal and the established ELM2, and the two evaluation results are linearly weighted fused through the established fan drive motor insulation impedance fusion evaluation model to obtain the final fan drive motor insulation impedance evaluation result (third evaluation result), and then according to the final fan drive motor insulation impedance evaluation result (the model of the fan drive motor insulation impedance), the corresponding principal components obtained from the AC voltage signal and the established ELM3, the insulation resistance value of the fan drive motor to ground and the capacitance value of the insulation capacitance to ground are obtained.

[0031] The advantages of the present invention are as follows: in view of the limitations of the existing insulation detection methods of the fan drive motors of the phase-shifting cooling towers in terms of real-time performance, labor costs, and detection cycles, and the existing online monitoring of the insulation of AC motors based on leakage current and impedance spectrum and the modeling methods of the insulation assessment model to the ground, a modeling method of the insulation assessment model to the ground of the fan drive motor of the cooling tower based on information fusion is proposed. The modeling method of the insulation assessment model to the ground of the fan drive motor of the phase-shifting cooling tower proposed by the present invention combines the common-mode leakage current signal and the vibration velocity signal of the fan drive motor of the phase-shifting cooling tower, and has the advantages of good real-time performance, non-intrusiveness, and high reliability, and provides a basis for the online monitoring of the insulation to the ground of the fan drive motor of the phase-shifting cooling tower.

[0032] Embodiment 2 Based on the method for evaluating the insulation of a fan drive motor to the ground described in the first embodiment, this embodiment provides a device for evaluating the insulation of a fan drive motor to the ground, including: A data acquisition module, used to collect vibration speed signals, common mode leakage current signals and AC voltage signals of the fan drive motor; A common-mode leakage current evaluation module is used to obtain an effective value of the common-mode leakage current signal of the fan drive motor according to the common-mode leakage current signal of the fan drive motor, and input the effective value of the common-mode leakage current signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 1 to obtain a first evaluation result; A vibration speed evaluation module, used for inputting the vibration speed signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; A fusion evaluation module, used for inputting the first evaluation result and the second evaluation result into a constructed fusion evaluation model of insulation impedance of a fan drive motor to ground, to obtain a third evaluation result; The ground insulation evaluation module is used to input the third evaluation result and the corresponding principal component obtained from the AC voltage signal into the fan drive motor ground insulation decoupling model to obtain the resistance value of the fan drive motor ground insulation resistance and the capacitance value of the fan drive motor ground insulation capacitance.

[0033] Embodiment 3 Based on the method for evaluating the insulation of a fan drive motor to the ground described in Example 1, this embodiment provides a computer device / equipment / system, including a memory, a processor, and a computer program stored in the memory, and the processor executes the computer program to implement the steps of the method for evaluating the insulation of a fan drive motor to the ground described in Example 1.

[0034] It should be understood by those skilled in the art that the embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD ROM, optical storage, etc.) containing computer-usable program code.

[0035] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0036] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0037] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0038] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A method for evaluating the insulation of a fan drive motor to the ground, characterized in that: include: Collect the vibration speed signal, common mode leakage current signal and AC voltage signal of the fan drive motor; According to the common-mode leakage current signal of the fan drive motor, an effective value of the common-mode leakage current signal of the fan drive motor is obtained, and the effective value of the common-mode leakage current signal of the fan drive motor is input into the constructed fan drive motor insulation impedance to ground evaluation model 1 to obtain a first evaluation result; Inputting the vibration speed signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; The first evaluation result and the second evaluation result are input into the constructed fusion evaluation model of the insulation impedance of the fan drive motor to the ground to obtain a third evaluation result; The third evaluation result and the corresponding principal component obtained from the AC voltage signal are input into a fan drive motor ground insulation decoupling model to obtain the resistance value of the fan drive motor ground insulation resistance and the capacitance value of the fan drive motor ground insulation capacitance.

2. The method for evaluating the insulation of a fan drive motor to the ground according to claim 1, characterized in that: Taking the effective value of the common-mode leakage current signal of the fan drive motor as input and the mode of the insulation impedance of the fan drive motor to the ground as output, the extreme learning machine is trained through the constructed fan drive motor to the ground insulation fault sample set to obtain the first evaluation model of the fan drive motor to the ground insulation impedance; Taking the vibration speed signal of the fan drive motor as input and the model of the insulation impedance of the fan drive motor to the ground as output, the extreme learning machine is trained through the constructed fan drive motor to the ground insulation fault sample set to obtain the second evaluation model of the fan drive motor to the ground insulation impedance; By constructing a fan drive motor to ground insulation fault sample set, a correlation analysis is performed on the effective value of the fan drive motor common mode leakage current signal and the mode of the fan drive motor to ground insulation impedance to obtain a first correlation coefficient; The vibration speed signal of the fan drive motor and the module of the fan drive motor insulation impedance to the ground are analyzed through the constructed fan drive motor insulation fault sample set to obtain the second correlation coefficient; A fusion evaluation model for insulation impedance of a fan drive motor to ground is established according to the first correlation coefficient and the second correlation coefficient, which linearly weights the first evaluation result and the second evaluation result; The modulus of the insulation impedance of the fan drive motor to the ground and the main components of the AC voltage signal after amplification and DC bias are taken as input, and the resistance value of the insulation resistance of the fan drive motor to the ground and the capacitance value of the insulation capacitance to the ground are taken as output. The extreme learning machine is trained by using the constructed fan drive motor to ground insulation fault sample set to obtain the fan drive motor to ground insulation decoupling model.

3. The method for evaluating the insulation of a fan drive motor to the ground according to claim 2, characterized in that: A method for constructing a sample set of insulation faults of a fan drive motor to ground includes: A different ground insulation fault is set at a certain phase of the stator of the fan drive motor, wherein the ground insulation fault is formed by a group of parallel ground insulation resistors and ground insulation capacitors, and different ground insulation faults are formed when the resistance value of the ground insulation resistor or the capacitance value of the ground insulation capacitor is different; When a certain type of ground insulation fault is set, the common-mode leakage current signal of the fan drive motor is collected, and the corresponding AC voltage signal is output, and then the signal is amplified through the instrument amplifier circuit. At this time, it is divided into two paths. One amplified AC voltage signal passes through the effective value circuit and the restoration operation in the DSP to obtain the effective value of the common-mode leakage current signal of the fan drive motor, and the other amplified AC voltage signal passes through the DC bias circuit, and then the discrete Fourier transform and principal component analysis are performed to obtain the AC voltage signal amplitudes of several set frequencies, and the vibration speed signal of the fan drive motor is obtained, thereby forming a fan drive motor ground insulation fault sample, wherein the input of the fan drive motor ground insulation fault sample includes the effective value of the fan drive motor common-mode leakage current signal, the fan drive motor vibration speed signal, and the AC voltage signal amplitudes of several set frequencies, and the output of the fan drive motor ground insulation fault sample includes the resistance value of the fan drive motor ground insulation resistance, the capacitance value of the ground insulation capacitance, and the mode of the ground insulation impedance; Different ground insulation fault samples of fan drive motors are obtained by setting different ground insulation faults to form an initial ground insulation fault sample set; Principal component analysis is performed on the amplitude parts of different frequencies in each sample input of the initial ground insulation fault sample set, and the number of extracted components k is determined according to the set extraction conditions. The first k components are then used to replace the amplitude parts of different frequencies in the sample input of the initial ground insulation fault sample set, thereby obtaining the fan drive motor ground insulation fault sample set.

4. The method for evaluating the insulation of a fan drive motor to the ground according to claim 3, characterized in that: The common-mode leakage current signal of the fan drive motor is collected through a zero-flux leakage current sensor; the vibration speed signal of the fan drive motor is obtained through a vibration speed sensor.

5. The method for evaluating the insulation of a fan drive motor to the ground according to claim 3, characterized in that: The extraction conditions set include: the percentage of explained variance to total variance is greater than 90%.

6. The method for evaluating the insulation of a fan drive motor to the ground according to claim 3, characterized in that: The first correlation coefficient and the second correlation coefficient are both Pearson correlation coefficients, and the calculation method is: ， ， Among them, the first correlation coefficient is the Pearson correlation coefficient between the effective value of the common-mode leakage current signal of the fan drive motor and the mode of the insulation impedance of the fan drive motor to the ground; the second correlation coefficient is the Pearson correlation coefficient between the vibration speed signal of the fan drive motor and the module of the insulation impedance of the fan drive motor to ground; The number of samples in the fan drive motor ground insulation fault sample set; This is the first sample of the fan drive motor insulation fault sample. The effective value of the fan drive motor common mode leakage current signal in the input of samples, ; This is the first sample of the fan drive motor insulation fault sample. The vibration speed signal of the fan drive motor in the input of samples; This is the first sample of the fan drive motor insulation fault sample. The model of the insulation impedance of the fan drive motor to ground in the output of each sample; is the mean value of the effective value of the common mode leakage current signal of each sample fan drive motor in the fan drive motor insulation fault sample set; is the mean value of the vibration speed signal of each sample fan drive motor in the fan drive motor insulation fault sample set; It is the mean value of the module of the insulation impedance of each fan drive motor to ground in the fan drive motor to ground insulation fault sample set.

7. The method for evaluating the insulation of a fan drive motor to the ground according to claim 6, characterized in that: The insulation impedance fusion assessment model of the fan drive motor to ground is: ， in, A first evaluation result output by a first evaluation model for evaluating the insulation impedance of a fan drive motor to ground; is a second evaluation result output by the second wind turbine drive motor insulation impedance evaluation model; It is the third evaluation result output by the fusion evaluation model of the insulation impedance of the wind turbine drive motor to the ground.

8. The method for evaluating the insulation of a fan drive motor to the ground according to claim 3, characterized in that: The method for obtaining the corresponding principal components obtained from the AC voltage signal includes: amplifying the AC voltage signal, DC biasing, and then performing a discrete Fourier transform to obtain the amplitudes of different frequencies, and then combining the principal component analysis results when constructing a fan drive motor to ground insulation fault sample set, converting the discrete Fourier transform results to obtain the corresponding principal components.

9. A device for evaluating the insulation of a fan drive motor to the ground, characterized in that: include: A data acquisition module, used to collect vibration speed signals, common mode leakage current signals and AC voltage signals of the fan drive motor; A common-mode leakage current evaluation module is used to obtain an effective value of the common-mode leakage current signal of the fan drive motor according to the common-mode leakage current signal of the fan drive motor, and input the effective value of the common-mode leakage current signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 1 to obtain a first evaluation result; A vibration speed evaluation module, used for inputting the vibration speed signal of the fan drive motor into the constructed fan drive motor insulation impedance evaluation model 2 to obtain a second evaluation result; A fusion evaluation module, used for inputting the first evaluation result and the second evaluation result into a constructed fusion evaluation model of insulation impedance of a fan drive motor to ground, to obtain a third evaluation result; The ground insulation evaluation module is used to input the third evaluation result and the corresponding principal component obtained from the AC voltage signal into the fan drive motor ground insulation decoupling model to obtain the resistance value of the fan drive motor ground insulation resistance and the capacitance value of the fan drive motor ground insulation capacitance.

10. A computer device / equipment / system comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method for evaluating the insulation of a wind turbine drive motor to the ground as described in any one of claims 1 to 8.

Images