Capacitance detection method, device and system for traction converter
By collecting and analyzing the input parameters of the traction converter, generating the double frequency power and DC components, calculating the capacitance value, and using the traction converter's own sensor for detection, it solves the problem of high cost and difficulty of capacitance detection in the prior art. , realizes efficient and reliable capacitance detection.
Patent Information
- Application Number
- CN202411219773.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-02
- Publication Date
- 2024-12-13
AI Technical Summary
The existing traction converter capacitance detection technology requires the addition of additional circuit devices, which leads to high costs and difficult application, making it difficult to effectively promote in high-speed train environments.
By collecting the input current, input voltage, input voltage frequency and capacitance voltage of the traction converter, we generate double frequency power and DC components, combine spectrum analysis to calculate the capacitance value, realize capacitance detection, and use the traction converter's own sensor and control The unit performs inspection to avoid additional equipment.
It improves the efficiency of capacitance detection, reduces equipment costs and operation difficulty, and realizes reliable capacitance detection in high-speed train environments.
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Figure CN119125714A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of rail transit vehicles, and in particular to a capacitance detection method, device and system for a traction inverter. Background Art
[0002] Traction inverter is a key component of rail train energy conversion, providing traction and braking force for the train. Capacitor is a key electrical component in traction inverter, and its operating condition will affect the reliability and safety of the train. The operating environment of high-speed trains is complex, and the performance degradation and fatigue accumulation damage of capacitors will threaten the safe and stable operation of the train. Therefore, it is of great significance to carry out performance testing on capacitors in traction inverters.
[0003] However, existing capacitance detection technologies often require the addition of some additional circuit components, which increases circuit costs and is difficult to promote in practical applications. Summary of the invention
[0004] In view of the problems in the prior art, the present application provides a capacitance detection method, device and system for a traction inverter, which can at least partially solve the problems in the prior art.
[0005] In a first aspect, the present application provides a capacitance detection method for a traction converter, comprising:
[0006] collecting an input current of the traction converter, an input voltage of the traction converter, an input voltage frequency of the traction converter, and a voltage of a capacitor of the traction converter;
[0007] Generate a double frequency power according to the input current and the input voltage, and generate a DC component and a double frequency voltage according to the voltage of the capacitor;
[0008] A capacitance value is generated according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitance.
[0009] Further, generating double frequency power according to the input current and the input voltage includes:
[0010] generating input instantaneous power according to the input current and the input voltage;
[0011] A double frequency power is generated according to the input instantaneous power.
[0012] Further, generating the double frequency power according to the input instantaneous power includes:
[0013] Performing spectrum analysis on the input instantaneous power to obtain a first analysis result;
[0014] The double frequency power is generated according to the first analysis result.
[0015] Further, the generating of a DC component and a double frequency voltage according to the voltage of the capacitor includes:
[0016] Performing spectrum analysis on the voltage of the capacitor to obtain a second analysis result;
[0017] A DC component and a double frequency voltage are generated according to the second analysis result.
[0018] Furthermore, it also includes:
[0019] The capacitance is detected according to the capacitance value and the acquired actual capacitance value.
[0020] In a second aspect, the present application provides a capacitance detection device for a traction converter, comprising:
[0021] a signal acquisition unit, configured to acquire an input current of the traction converter, an input voltage of the traction converter, an input voltage frequency of the traction converter, and a voltage of a capacitor of the traction converter;
[0022] A first processing unit, configured to generate a double frequency power according to the input current and the input voltage, and to generate a DC component and a double frequency voltage according to the voltage of the capacitor;
[0023] The second processing unit is used to generate a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency, so as to detect the capacitance.
[0024] Furthermore, the first processing unit includes:
[0025] An instantaneous power generation module, used for generating input instantaneous power according to the input current and the input voltage;
[0026] The double frequency power generation module is used to generate double frequency power according to the input instantaneous power.
[0027] Furthermore, the double frequency power generation module comprises:
[0028] A first spectrum analysis submodule, used for performing spectrum analysis on the input instantaneous power to obtain a first analysis result;
[0029] The double frequency power generation submodule is used to generate double frequency power according to the first analysis result.
[0030] Furthermore, the first processing unit further includes:
[0031] A second spectrum analysis module, used for performing spectrum analysis on the voltage of the capacitor to obtain a second analysis result;
[0032] The double frequency voltage generating module is used to generate a DC component and a double frequency voltage according to the second analysis result.
[0033] Furthermore, it also includes:
[0034] The third processing unit is used to detect the capacitance according to the capacitance value and the acquired actual capacitance value.
[0035] In a third aspect, the present application provides a capacitance detection system for a traction converter, comprising: an input current sensor, an input voltage sensor, an intermediate voltage sensor, and a capacitance detection device for a traction converter according to any one of the above embodiments;
[0036] The input current sensor is connected to the capacitance detection device and is used to measure the input current of the traction converter;
[0037] The input voltage sensor is connected to the capacitance detection device and is used to measure the input voltage and input voltage frequency of the traction converter;
[0038] The intermediate voltage sensor is connected to the capacitance detection device and is used to measure the voltage of the capacitor.
[0039] In a fourth aspect, the present application provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method described in any of the above embodiments when executing the computer program.
[0040] In a fifth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in any of the above embodiments is implemented.
[0041] In a sixth aspect, the present application provides a computer program product, wherein the computer program product includes a computer program, and when the computer program is executed by a processor, the method described in any of the above embodiments is implemented.
[0042] The capacitance detection method, device and system of the traction converter provided by the present application collect the input current of the traction converter, the input voltage of the traction converter, the input voltage frequency of the traction converter and the voltage of the capacitor of the traction converter; generate double frequency power according to the input current and the input voltage, and generate a DC component and double frequency voltage according to the voltage of the capacitor; generate a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitor, thereby effectively improving the detection efficiency of the capacitor. Among them, the capacitance detection is performed through the sensor and traction control unit of the traction converter itself, without the need to add other detection equipment, thereby reducing equipment cost and operation difficulty. BRIEF DESCRIPTION OF THE DRAWINGS
[0043] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0044] Figure 1 is a flow chart of a capacitance detection method for a traction converter provided in one embodiment of the present application;
[0045] Figure 2 is a flow chart of a capacitance detection method for a traction converter provided in one embodiment of the present application;
[0046] Figure 3 is a flow chart of a capacitance detection method for a traction converter provided in one embodiment of the present application;
[0047] Figure 4 is a flow chart of a capacitance detection method for a traction converter provided in one embodiment of the present application;
[0048] Figure 5 is a structural schematic diagram of a capacitance detection device for a traction converter provided in one embodiment of the present application;
[0049] Figure 6 is a structural schematic diagram of a capacitance detection device for a traction converter provided in one embodiment of the present application;
[0050] Figure 7 is a structural schematic diagram of a capacitance detection device for a traction converter provided in one embodiment of the present application;
[0051] Figure 8 is a structural schematic diagram of a capacitance detection device for a traction converter provided in one embodiment of the present application;
[0052] Fig. 9 is a structural schematic diagram of a capacitance detection device for a traction converter provided in one embodiment of the present application;
[0053] Fig.10 is a schematic diagram of the physical structure of an electronic device provided in one embodiment of the present application;
[0054] Fig.11 is a structural schematic diagram of a traction converter provided in one embodiment of the present application;
[0055] Fig.12 is a schematic diagram of a first analysis result provided by an embodiment of the present application;
[0056] Fig.13 is a schematic diagram of a second analysis result provided in an embodiment of the present application;
[0057] Fig.14 is a comparison diagram between a generated capacitance value and an actual capacitance value provided in an embodiment of the present application. DETAILED DESCRIPTION
[0058] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention. It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other arbitrarily.
[0059] The structure of the traction converter is as follows: Fig.11 As shown, it includes an input current sensor 1, an input voltage sensor 2, a rectifier 3, a capacitor 4, an intermediate voltage sensor 5, an inverter 6, a motor 7 and a traction control unit 8, and the traction control unit 8 includes a signal acquisition board 9 and a signal processing board 10. Among them, the rectifier 3 is used to convert AC power into DC power; the inverter 6 is used to convert DC power into AC power with adjustable frequency and amplitude to drive the motor 7; the motor 7 is used to drive the train to run. The present application uses the input current sensor 1, the input voltage sensor 2, the intermediate voltage sensor 5 and the traction control unit 8 of the traction converter to detect the capacitor 4 of the traction converter.
[0060] The following takes the traction control unit of the traction converter as an example of the execution subject to illustrate the specific implementation process of the capacitance detection method of the traction converter provided by the embodiment of the present invention.
[0061] Figure 1 is a flow chart of a capacitance detection method for a traction converter provided in an embodiment of the present application. Figure 1 As shown, the capacitance detection method of the traction converter provided by the present application includes:
[0062] S101: collecting an input current of the traction converter, an input voltage of the traction converter, an input voltage frequency of the traction converter, and a voltage of a capacitor of the traction converter;
[0063] S102: generating a double frequency power according to the input current and the input voltage, and generating a DC component and a double frequency voltage according to the voltage of the capacitor;
[0064] S103: Generate a capacitance value according to the doubled frequency power, the DC component, the doubled frequency voltage and the input voltage frequency to detect the capacitance.
[0065] from Figure 1 It can be seen from the shown process that the capacitance detection method of the traction inverter provided in the present application collects the input current of the traction inverter, the input voltage of the traction inverter, the input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter; generates a double frequency power according to the input current and the input voltage, and generates a DC component and a double frequency voltage according to the voltage of the capacitor; generates a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitance, thereby effectively improving the detection efficiency of the capacitor.
[0066] Each step is explained in detail below.
[0067] S101: collecting an input current of the traction converter, an input voltage of the traction converter, an input voltage frequency of the traction converter, and a voltage of a capacitor of the traction converter;
[0068] Specifically, the signal acquisition board of the traction control unit collects the measured input current, input voltage, input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter, so as to generate a capacitance value and detect the capacitance using the input current, input voltage, input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter.
[0069] S102: generating a double frequency power according to the input current and the input voltage, and generating a DC component and a double frequency voltage according to the voltage of the capacitor;
[0070] Specifically, the signal processing board of the traction control unit uses the input current and input voltage of the traction converter to generate double frequency power, that is, the amplitude of the input instantaneous power at twice the input voltage frequency; the signal processing board of the traction control unit also uses the voltage of the capacitor of the traction converter to generate a DC component and a double frequency voltage, wherein the DC component is the amplitude of the capacitor voltage at zero frequency, and the double frequency voltage is the amplitude of the capacitor voltage at twice the input voltage frequency. The signal processing board of the traction control unit generates double frequency power, DC component and double frequency voltage to generate capacitance value and detect the capacitance of the traction converter.
[0071] Figure 2 is a flow chart of a capacitance detection method for a traction converter provided in an embodiment of the present application, such as Figure 2 As shown, generating the double frequency power according to the input current and the input voltage in S102 includes:
[0072] S201: generating input instantaneous power according to the input current and the input voltage;
[0073] Specifically, the signal processing board of the traction control unit uses the input current and input voltage to calculate the input instantaneous power, which is expressed as follows:
[0074] P in =I in ×U in (1)
[0075] Where P in Indicates the instantaneous input power, I in Indicates the input current of the traction converter, U in Indicates the input voltage of the traction converter.
[0076] S202: Generate double frequency power according to the input instantaneous power.
[0077] Specifically, the input voltage and input current of the traction converter can be expressed as:
[0078] U in =U dc coS(ωt) (2)
[0079] I in =I dc cos(ωt) (3)
[0080] Where U dc Represents the DC component of the input voltage, I dc It represents the DC component of the input current, ω represents the angular frequency of the input voltage, that is, when the supply voltage is 50Hz, ω=100πr rad / s.
[0081] Therefore, the input instantaneous power of the traction converter can be expressed as:
[0082] P in =I in ×U in =U dc I dc cos(ωt) 2 =U dc I dc [1-cos(2ωt)] (4)
[0083] Where U dc Represents the DC component of the input voltage, I dc It represents the DC component of the input current, and ω represents the angular frequency of the input voltage, that is, when the supply voltage is 50Hz, ω=100πrad / s.
[0084] From the above formula, we can see that the input instantaneous power of the traction converter contains not only the DC component U dc I dc In addition, it also contains an AC component, the frequency of the AC component is twice the input voltage, that is, twice the input voltage frequency. This double-frequency power component will produce double-frequency voltage fluctuations in the capacitor.
[0085] Therefore, the signal processing board of the traction control unit can generate a capacitance value based on the double frequency power, the DC component of the capacitor voltage and the double frequency voltage and detect the capacitance of the traction converter.
[0086] The signal processing board of the traction control unit uses the input instantaneous power calculated based on the input current and input voltage to generate the double frequency power, that is, the amplitude corresponding to the input instantaneous power at twice the input voltage frequency.
[0087] Figure 3 is a flow chart of a capacitance detection method for a traction converter provided in an embodiment of the present application, such as Figure 3 As shown, S202 includes:
[0088] S301: Performing spectrum analysis on the input instantaneous power to obtain a first analysis result;
[0089] Specifically, the signal processing board of the traction control unit performs spectrum analysis on the input instantaneous power to obtain a spectrum analysis result to generate double frequency power according to the spectrum analysis result, that is, the amplitude corresponding to the input instantaneous power at twice the input voltage frequency.
[0090] In one embodiment, the signal processing board of the traction control unit may use the Fourier transform method to perform spectrum analysis on the input instantaneous power, but the present application is not limited thereto.
[0091] The Fourier transform method is used to represent the input instantaneous power as an infinite superposition of sine waves and cosine waves of different frequencies. The frequency, amplitude and phase of these sine waves and cosine waves are the basic components of the input instantaneous power. By performing spectrum analysis on the input instantaneous power using the Fourier transform method, the amplitude and phase information of each frequency component in the input instantaneous power can be clearly understood.
[0092] For example, the Fourier transform method is used to perform spectrum analysis on the input instantaneous power and convert the input instantaneous power P in (t) is expressed as:
[0093]
[0094] Where a0 is a constant term, representing the DC component of all harmonics, and a n is the amplitude of the cosine wave, representing the cosine component of the nth harmonic, b n is the amplitude of the sine wave, representing the sinusoidal component of the nth harmonic, where n is a positive integer representing the ordinal number of the harmonic.
[0095] The above formula converts the input instantaneous power P in (t) is expressed as the superposition of the DC component and each AC component, so that the double frequency component of the input instantaneous power can be extracted.
[0096] S302: Generate double frequency power according to the first analysis result.
[0097] Specifically, the analysis results of the spectrum analysis of the input instantaneous power are as follows: Fig.12 As shown, the signal processing board of the traction control unit extracts the double frequency power from the spectrum analysis result, that is, the amplitude corresponding to the input instantaneous power at twice the input voltage frequency.
[0098] For example, when the supply voltage is 50Hz, twice the input voltage frequency is 100Hz. Fig.12 From the analysis results shown, it is possible to extract the amplitude of the input instantaneous power at twice the input voltage frequency, that is, the amplitude of the input instantaneous power at 100 Hz, which is 1.25 MW.
[0099] Figure 4 is a flow chart of a capacitance detection method for a traction converter provided in an embodiment of the present application, such as Figure 4 As shown, generating a DC component and a double frequency voltage according to the voltage of the capacitor in S102 includes:
[0100] S401: performing spectrum analysis on the voltage of the capacitor to obtain a second analysis result;
[0101] Specifically, the signal processing board of the traction control unit performs spectral analysis on the voltage of the capacitor to obtain spectral analysis results to generate a DC component and a double-frequency voltage according to the spectral analysis results, wherein the DC component is the amplitude of the capacitor voltage at zero frequency, and the double-frequency voltage is the amplitude of the capacitor voltage at twice the input voltage frequency.
[0102] In one embodiment, the signal processing board of the traction control unit may use the Fourier transform method to perform spectrum analysis on the voltage of the capacitor, but the present application is not limited thereto.
[0103] The Fourier transform method is used to represent the voltage of the capacitor as an infinite superposition of sine waves and cosine waves of different frequencies. The frequency, amplitude and phase of these sine waves and cosine waves are the basic components of the capacitor voltage. By performing spectrum analysis on the capacitor voltage using the Fourier transform method, the amplitude and phase information of each frequency component in the capacitor voltage can be clearly understood.
[0104] For example, the Fourier transform method is used to perform spectrum analysis on the capacitor voltage, and the capacitor voltage U(t) is expressed as:
[0105]
[0106] Where c0 is a constant term, representing the DC component of all harmonics, c n is the amplitude of the cosine wave, representing the cosine component of the nth harmonic, d n is the amplitude of the sine wave, representing the sinusoidal component of the nth harmonic, where n is a positive integer representing the ordinal number of the harmonic.
[0107] The above formula expresses the capacitor voltage U(t) as a superposition of a DC component and each AC component, thereby being able to extract the DC component and double frequency component of the capacitor voltage.
[0108] S402: Generate a DC component and a double frequency voltage according to the second analysis result.
[0109] Specifically, the analysis results of the spectrum analysis of the capacitor voltage are as follows: Fig.13 As shown, the signal processing board of the traction control unit extracts the DC component and the double frequency voltage from the spectrum analysis results, wherein the DC component is the amplitude of the capacitor voltage at zero frequency, and the double frequency voltage is the amplitude of the capacitor voltage at twice the input voltage frequency.
[0110] For example, when the supply voltage is 50Hz, twice the input voltage frequency is 100Hz. Fig.13From the analysis results shown, the amplitude of the capacitor voltage at zero frequency and twice the input voltage frequency can be extracted. The DC component is the amplitude of the capacitor voltage at 0Hz, which is 1800V, and the double frequency voltage is the amplitude of the capacitor voltage at 100Hz, which is 45V.
[0111] S103: Generate a capacitance value according to the doubled frequency power, the DC component, the doubled frequency voltage and the input voltage frequency to detect the capacitance.
[0112] Specifically, the signal processing board of the traction control unit generates a capacitance value C using double frequency power, DC component, double frequency voltage and input voltage frequency, which is expressed as follows:
[0113]
[0114] Where P 2Fin Indicates the double frequency power, U dc1 Represents the DC component of the capacitor voltage, U 2Fin Indicates the double frequency voltage, F in Indicates the input voltage frequency.
[0115] The signal processing board of the traction control unit can detect the capacitance of the traction converter according to the capacitance value generated by the double frequency power, DC component, double frequency voltage and input voltage frequency.
[0116] In one embodiment, the capacitance detection method of the traction converter provided by the present application further includes:
[0117] The capacitance is detected according to the capacitance value and the acquired actual capacitance value.
[0118] Specifically, the actual capacitance value is the reference value of the capacitance of the traction inverter. The signal processing board of the traction control unit compares the capacitance value generated according to the double-frequency power, DC component, double-frequency voltage and input voltage frequency with the actual capacitance value to check the loss state of the capacitance of the traction inverter. If the generated capacitance value is lower than eighty percent of the actual capacitance value, the capacitor of the traction inverter needs to be replaced.
[0119] like Fig.14 The figure shows the verification result of the capacitance value generated by the capacitance detection method of the traction converter provided by the present application. Fig.14 It can be seen that at different vehicle speeds, the error between the capacitance value generated by the capacitance detection method for the traction inverter provided in the present application and the actual capacitance value is within 2%, which has high accuracy.
[0120] The capacitance detection method of the traction converter provided by the present application collects the input current of the traction converter, the input voltage of the traction converter, the input voltage frequency of the traction converter and the voltage of the capacitor of the traction converter; generates double frequency power according to the input current and the input voltage, and generates a DC component and double frequency voltage according to the voltage of the capacitor; generates a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitor, thereby effectively improving the detection efficiency of the capacitor. Among them, the capacitance detection is performed through the sensor and traction control unit of the traction converter itself, without the need to add other detection equipment, thereby reducing the equipment cost and operation difficulty.
[0121] Based on the same inventive concept, the embodiments of the present application also provide a capacitance detection device for a traction converter, which can be used to implement the method described in the above embodiments, as described in the following embodiments. Since the principle of solving the problem by the capacitance detection device for the traction converter is similar to that of the capacitance detection method for the traction converter, the implementation of the capacitance detection device for the traction converter can refer to the implementation of the method based on software performance benchmark determination, and the repeated parts will not be repeated. As used below, the terms "unit" or "module" can be a combination of software and / or hardware that implements predetermined functions. Although the system described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.
[0122] Figure 5 is a structural schematic diagram of a capacitance detection device for a traction converter provided in an embodiment of the present application, such as Figure 5 As shown, the capacitance detection device of the traction converter provided in the present application includes:
[0123] A signal acquisition unit 501 is used to collect the input current of the traction converter, the input voltage of the traction converter, the input voltage frequency of the traction converter and the voltage of the capacitor of the traction converter;
[0124] Specifically, the signal acquisition board of the traction control unit of the traction inverter performs the function of the signal acquisition unit, and the signal acquisition board of the control unit acquires the measured input current, input voltage, input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter, so as to generate a capacitance value and detect the capacitance using the input current, input voltage, input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter.
[0125] A first processing unit 502, configured to generate a double frequency power according to the input current and the input voltage, and to generate a DC component and a double frequency voltage according to the voltage of the capacitor;
[0126] Specifically, the signal processing board of the traction control unit of the traction converter performs the function of the first processing unit. The signal processing board of the traction control unit generates double frequency power using the input current and input voltage of the traction converter, that is, the amplitude corresponding to the input instantaneous power at twice the input voltage frequency. The signal processing board of the traction control unit also generates a DC component and a double frequency voltage using the voltage of the capacitor of the traction converter, wherein the DC component is the amplitude corresponding to the capacitor voltage at zero frequency, and the double frequency voltage is the amplitude corresponding to the capacitor voltage at twice the input voltage frequency. The signal processing board of the traction control unit generates double frequency power, DC component and double frequency voltage to generate a capacitance value and detect the capacitance of the traction converter.
[0127] The second processing unit 503 is used to generate a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency, so as to detect the capacitance.
[0128] Specifically, the function of the second processing unit is performed by the signal processing card of the traction control unit of the traction converter. The signal processing card of the traction control unit generates a capacitance value C using double frequency power, a DC component, double frequency voltage and an input voltage frequency, which is expressed as follows:
[0129]
[0130] Where P 2Fin Indicates the double frequency power, U dc1 Represents the DC component of the capacitor voltage, U 2Fin Indicates the double frequency voltage, F in Indicates the input voltage frequency.
[0131] The signal processing board of the traction control unit can detect the capacitance of the traction converter according to the capacitance value generated by the double frequency power, DC component, double frequency voltage and input voltage frequency.
[0132] Figure 6 is a schematic diagram of the structure of a capacitance detection device for a traction converter provided in an embodiment of the present application. Figure 5 Based on the embodiment, further, Figure 6 As shown, the capacitance detection device of the traction converter provided by the present application also includes:
[0133] An instantaneous power generation module 601 is used to generate input instantaneous power according to the input current and the input voltage;
[0134] The double frequency power generation module 602 is used to generate double frequency power according to the input instantaneous power.
[0135] Figure 7is a structural schematic diagram of a capacitance detection device for a traction converter provided in an embodiment of the present application, Figure 5 Based on the embodiment, further, Figure 7 As shown, the capacitance detection device of the traction converter provided by the present application also includes:
[0136] A first spectrum analysis submodule 701, configured to perform spectrum analysis on the input instantaneous power to obtain a first analysis result;
[0137] The double frequency power generation submodule 702 is used to generate double frequency power according to the first analysis result.
[0138] Figure 8 is a structural schematic diagram of a capacitance detection device for a traction converter provided in an embodiment of the present application, Figure 5 Based on the embodiment, further, Figure 8 As shown, the capacitance detection device of the traction converter provided by the present application also includes:
[0139] A second spectrum analysis module 801, configured to perform spectrum analysis on the voltage of the capacitor to obtain a second analysis result;
[0140] The double frequency voltage generating module 802 is used to generate a DC component and a double frequency voltage according to the second analysis result.
[0141] Fig. 9 is a schematic diagram of the structure of a capacitance detection device for a traction converter provided in an embodiment of the present application. Figure 5 Based on the embodiment, further, Fig. 9 As shown, the capacitance detection device of the traction converter provided by the present application also includes:
[0142] The third processing unit 901 is used to detect the capacitance according to the capacitance value and the acquired actual capacitance value.
[0143] Specifically, the function of the third processing unit is executed by the signal processing board of the traction control unit of the traction inverter. The actual capacitance value is the reference value of the capacitance of the traction inverter. The signal processing board of the traction control unit compares the capacitance value generated according to the double-frequency power, DC component, double-frequency voltage and input voltage frequency with the actual capacitance value to check the loss state of the capacitance of the traction inverter. If the generated capacitance value is lower than eighty percent of the actual capacitance value, the capacitor of the traction inverter needs to be replaced.
[0144] The capacitance detection method and device of the traction converter provided by the present application collects the input current of the traction converter, the input voltage of the traction converter, the input voltage frequency of the traction converter and the voltage of the capacitor of the traction converter; generates double frequency power according to the input current and the input voltage, and generates a DC component and double frequency voltage according to the voltage of the capacitor; generates a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitor, thereby effectively improving the detection efficiency of the capacitor. Among them, the capacitance detection is performed through the sensor and traction control unit of the traction converter itself, without the need to add other detection equipment, thereby reducing the equipment cost and operation difficulty.
[0145] In addition, the present application also provides a capacitance detection system for a traction converter, the system comprising: an input current sensor, an input voltage sensor, an intermediate voltage sensor, and a capacitance detection device for a traction converter provided by any of the above embodiments;
[0146] The input current sensor is connected to the capacitance detection device and is used to measure the input current of the traction converter;
[0147] The input voltage sensor is connected to the capacitance detection device and is used to measure the input voltage and input voltage frequency of the traction converter;
[0148] The intermediate voltage sensor is connected to the capacitance detection device and is used to measure the voltage of the capacitor.
[0149] Fig.10 is a schematic diagram of the physical structure of an electronic device provided in an embodiment of the present application, such as Fig.10 As shown, the electronic device may include: a processor 1001, a communication interface 1002, a memory 1003 and a communication bus 1004, wherein the processor 1001, the communication interface 1002 and the memory 1003 communicate with each other through the communication bus 1004. The processor 1001 may call the logic instructions in the memory 1003 to execute the following method: collecting the input current of the traction converter, the input voltage of the traction converter, the input voltage frequency of the traction converter and the voltage of the capacitor of the traction converter; generating a double frequency power according to the input current and the input voltage, and generating a DC component and a double frequency voltage according to the voltage of the capacitor; generating a capacitance value according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitance.
[0150] In addition, the logic instructions in the above-mentioned memory 1003 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art, and the computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk.
[0151] The present embodiment discloses a computer program product, which includes a computer program stored on a computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the methods provided by the above-mentioned method embodiments, for example, including: collecting the input current of the traction inverter, the input voltage of the traction inverter, the input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter; generating a double-frequency power according to the input current and the input voltage, and generating a DC component and a double-frequency voltage according to the voltage of the capacitor; generating a capacitance value according to the double-frequency power, the DC component, the double-frequency voltage and the input voltage frequency to detect the capacitance.
[0152] The present embodiment provides a computer-readable storage medium, which stores a computer program. The computer program enables the computer to execute the methods provided by the above-mentioned method embodiments, for example, including: collecting the input current of the traction inverter, the input voltage of the traction inverter, the input voltage frequency of the traction inverter and the voltage of the capacitor of the traction inverter; generating a double-frequency power according to the input current and the input voltage, and generating a DC component and a double-frequency voltage according to the voltage of the capacitor; generating a capacitance value according to the double-frequency power, the DC component, the double-frequency voltage and the input voltage frequency to detect the capacitance.
[0153] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.
[0154] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes 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 generate 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.
[0155] 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.
[0156] 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.
[0157] In the description of this specification, the description with reference to the terms "one embodiment", "a specific embodiment", "some embodiments", "for example", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.
[0158] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.
Claims
1. A capacitance detection method for a traction converter, characterized in that: include: collecting an input current of the traction converter, an input voltage of the traction converter, an input voltage frequency of the traction converter, and a voltage of a capacitor of the traction converter; Generate a double frequency power according to the input current and the input voltage, and generate a DC component and a double frequency voltage according to the voltage of the capacitor; A capacitance value is generated according to the double frequency power, the DC component, the double frequency voltage and the input voltage frequency to detect the capacitance.
2. The capacitance detection method of the traction converter according to claim 1, characterized in that: Generating the double frequency power according to the input current and the input voltage comprises: generating input instantaneous power according to the input current and the input voltage; A double frequency power is generated according to the input instantaneous power.
3. The capacitance detection method of the traction converter according to claim 2, characterized in that: Generating double frequency power according to the input instantaneous power includes: Performing spectrum analysis on the input instantaneous power to obtain a first analysis result; The double frequency power is generated according to the first analysis result.
4. The capacitance detection method of the traction converter according to claim 1, characterized in that: The step of generating a DC component and a double frequency voltage according to the voltage of the capacitor includes: Performing spectrum analysis on the voltage of the capacitor to obtain a second analysis result; A DC component and a double frequency voltage are generated according to the second analysis result.
5. The capacitance detection method of the traction converter according to claim 1, characterized in that: Also includes: The capacitance is detected according to the capacitance value and the acquired actual capacitance value.
6. A capacitance detection device for a traction converter, characterized in that: include: a signal acquisition unit, configured to acquire an input current of the traction converter, an input voltage of the traction converter, an input voltage frequency of the traction converter, and a voltage of a capacitor of the traction converter; A first processing unit, configured to generate a double frequency power according to the input current and the input voltage, and to generate a DC component and a double frequency voltage according to the voltage of the capacitor; The second processing unit is used to generate a capacitance value according to the doubled frequency power, the DC component, the doubled frequency voltage and the input voltage frequency, so as to detect the capacitance.
7. The capacitance detection device for a traction converter according to claim 6, characterized in that: The first processing unit comprises: An instantaneous power generation module, configured to generate input instantaneous power according to the input current and the input voltage; The double frequency power generation module is used to generate double frequency power according to the input instantaneous power.
8. The capacitance detection device for a traction converter according to claim 7, characterized in that: The double frequency power generation module comprises: A first spectrum analysis submodule, used for performing spectrum analysis on the input instantaneous power to obtain a first analysis result; The double frequency power generation submodule is used to generate double frequency power according to the first analysis result.
9. The capacitance detection device for a traction converter according to claim 6, characterized in that: The first processing unit further includes: A second spectrum analysis module, used for performing spectrum analysis on the voltage of the capacitor to obtain a second analysis result; The double frequency voltage generating module is used to generate a DC component and a double frequency voltage according to the second analysis result.
10. The capacitance detection device of the traction converter according to claim 6, characterized in that: Also includes: The third processing unit is used to detect the capacitance according to the capacitance value and the acquired actual capacitance value.
11. A capacitance detection system for a traction converter, characterized in that: include: An input current sensor, an input voltage sensor, an intermediate voltage sensor, and a capacitance detection device for a traction converter as claimed in any one of claims 6 to 10; The input current sensor is connected to the capacitance detection device and is used to measure the input current of the traction converter; The input voltage sensor is connected to the capacitance detection device and is used to measure the input voltage and input voltage frequency of the traction converter; The intermediate voltage sensor is connected to the capacitance detection device and is used to measure the voltage of the capacitor.
12. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 5 is implemented.
13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.
14. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.