Transformer winding inter-cake short circuit evaluation method based on multi-parameter fusion under oscillatory waves

Abstract

The invention discloses a multi-parameter fusion transformer winding inter-cake short circuit evaluation method under oscillatory waves, which comprises the following steps of: firstly, establishing a transformer oscillatory wave signal acquisition platform, acquiring winding oscillatory wave data, then serializing the acquired data, calculating multi-parameter values by utilizing the acquired data and historical data, and calculating the short circuit of the multi-parameter values; evaluating whether the inter-cake short circuit occurs in the transformer winding by fusing the multi-parameter values; according to the method, the transformer winding is detected by using an oscillatory wave and multi-parameter fusion method, so that the detection result is more reliable and accurate, corresponding reference data is provided for online detection of the transformer, and the method has important reference value for detecting safe operation of the transformer.

Description

Technical Field

[0001] The present invention belongs to the field of transformer online active detection, and in particular relates to a transformer winding inter-panel short circuit assessment method based on multi-parameter fusion under oscillation waves. Background Art

[0002] Transformers, as core equipment in power systems, play a critical role in power conversion, electrical isolation, and power distribution. They not only convert electricity from the high-voltage transmission network into low-voltage power suitable for domestic and industrial use, but also provide electrical isolation to ensure circuit safety. Furthermore, transformers distribute power within the power grid to meet regional needs. Therefore, the health of transformers is directly related to the stability and reliability of the entire power system. However, transformers may experience various faults during long-term operation, such as insulation aging, overload, and short circuits. These faults can lead to a decrease in power quality and affect normal power consumption. In severe cases, they can paralyze the power system, trigger large-scale power outages, and even pose a threat to personal safety. Inter-winding short circuits are one of the most common transformer faults. Therefore, monitoring the condition of transformer windings and promptly detecting and addressing potential inter-winding short circuits are crucial to ensuring stable power system operation.

[0003] The oscillation wave detection process is fast and efficient, requiring no long downtime, significantly reducing disruption to the normal power supply order. It is particularly suitable for regular "physical checks" of transformers in power grid operation, ensuring that the equipment is always in good condition. Furthermore, the technology's detection results are stable, reliable, and highly repeatable, providing technicians with an accurate basis for diagnosis, facilitating the development of precise maintenance strategies in advance, rationally arranging maintenance plans, extending the service life of transformers, and improving the overall stability and reliability of the power grid. It is an indispensable detection method in modern power systems. A multi-parameter fusion method for transformer winding inter-panel short-circuit assessment under oscillation waves utilizes oscillation waves combined with multiple parameters to comprehensively assess whether an inter-panel short-circuit fault has occurred in the transformer winding. This method can significantly improve the efficiency and accuracy of detecting inter-panel short-circuits in transformer windings, enhance the sensitivity and reliability of fault diagnosis, provide strong support for transformer health management and maintenance, and is of great significance for online transformer detection. Summary of the Invention

[0004] Online detection of transformers using oscillation waves can detect the status of the transformer without stopping the transformer. In order to make online detection of the transformer status more accurate and reliable, the present invention provides a transformer winding short-circuit assessment method based on multi-parameter fusion under oscillation waves.

[0005] A method for assessing short circuits between transformer windings using multi-parameter fusion under oscillation waves is characterized by: using oscillation waves to perform online detection of the transformer, calculating multi-parameter values ​​using the collected oscillation wave data, and then assessing whether short circuits between transformer windings occur. The method uses the oscillation waves to detect the transformer windings and calculates multi-parameter values ​​of the transformer winding oscillation waves to assess short circuits between transformer windings.

[0006] Step 1: Build a transformer oscillation wave signal acquisition platform to obtain winding oscillation wave data

[0007] The platform mainly consists of a transformer box (1), a transformer winding (2), a transformer winding neutral point (3), an output bushing (4), an input bushing (5), an oscillation wave signal acquisition device (6), an oscillation wave signal injection device (7), and a host computer platform (8);

[0008] The oscillation wave signal injection device (7) is connected to the input bushing (5), the input bushing (5) is connected to the neutral point (3) of the transformer winding, the winding (2) is connected to the output bushing (4), the output bushing (4) and the output bushing (5) are connected to the oscillation wave signal acquisition device (6), and the oscillation wave injection device (7) and the oscillation wave signal acquisition device (6) are connected to the host computer (9);

[0009] When the platform is working, the host computer sends a command to the oscillation wave signal injection device (7), the oscillation wave signal injection device (7) generates an oscillation wave signal, and injects the signal into the neutral point (3) of the transformer winding through the input bushing (5). The oscillation wave signal acquisition device (6) acquires the oscillation wave response signal and the oscillation wave injection signal of the transformer winding (2) connected to the output bushing (4), and sends them to the host computer (8). The transformer winding (2) connected to the output winding (4) can be any one of the three phases A, B, and C.

[0010] Step 2: The host computer generates a sequence of collected data

[0011] The host computer serializes the collected voltage signal according to the collection time, with the time unit being microseconds and the voltage unit being volts, and generates a voltage signal sequence related to the collection time and a sequence related to the collection time: v n ,n=0,1,2,……and t n ,n=0,1,2,……;

[0012] Step 3: Calculate the parameters

[0013] Calculate the parameter α according to formula (1):

[0014]

[0015] Where t 2x , t1x are the two moments when the normal winding has a peak under the oscillation wave, v 2x 、v 1x For normal winding at t 2x , t 1x The corresponding peak value, t2, t1 are the two moments when the winding peak appears under the oscillation wave, v2, v1 are the peak values ​​of the winding at t2, t1, v n is the collected oscillation wave voltage sequence, v xn is the oscillating wave voltage sequence of the normal winding, t n and t xn is the corresponding time series;

[0016] Calculate the parameter β according to formula (2):

[0017]

[0018] Where v n is the collected oscillation wave voltage sequence, v xn is the oscillating wave voltage sequence of the normal winding, t n and t xn is the corresponding time series;

[0019] Traverse the voltage signal sequence and find the voltage between two adjacent zero crossing points (v n ) and the corresponding time (t n ) sequence, x is the number of data points in the sequence, and the normal parameter s of the transformer under the oscillation wave is calculated according to formula (3): n and the collected oscillation wave parameters s c :

[0020]

[0021] Calculate the parameter γ according to formula (4):

[0022]

[0023] Where s n Normal parameters of transformer under oscillation wave, s c The collected oscillation wave parameters;

[0024] Step 4: Calculate the evaluation factor

[0025] The evaluation factor is calculated according to formula (5):

[0026] H=0.2α+0.1β+0.5γ (5)

[0027] H is the evaluation factor

[0028] Step 5: Evaluate the transformer winding using evaluation factors

[0029] When H<0.05, there is no short circuit fault between the transformer windings.

[0030] When H≥0.05, a short circuit fault occurs between the transformer windings.

[0031] The beneficial effects of the present invention are that the method can monitor the transformer using oscillation waves and use multiple parameters to evaluate the transformer winding status, making the diagnosis results of short-circuit faults between windings more reliable and accurate, providing corresponding reference data for online detection of transformers, and having important reference value for detecting the safe operation of transformers. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is the structural diagram of the experimental platform of the present invention. Figure 2 Flowchart of the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings:

[0034] Figure 1 The structure diagram of the experimental platform built. Figure 2 The figure shows a flow chart of a transformer winding short circuit assessment method based on multi-parameter fusion under oscillation wave. Figure 2 It can be seen that a transformer winding short circuit assessment method based on multi-parameter fusion under oscillation wave includes the following steps:

[0035] Step 1: Build a transformer oscillation wave signal acquisition platform to obtain winding oscillation wave data

[0036] The platform mainly consists of a transformer box (1), a transformer winding (2), a transformer winding neutral point (3), an output bushing (4), an input bushing (5), an oscillation wave signal acquisition device (6), an oscillation wave signal injection device (7), and a host computer platform (8);

[0037] The oscillation wave signal injection device (7) is connected to the input bushing (5), the input bushing (5) is connected to the neutral point (3) of the transformer winding, the winding (2) is connected to the output bushing (4), the output bushing (4) and the output bushing (5) are connected to the oscillation wave signal acquisition device (6), and the oscillation wave injection device (7) and the oscillation wave signal acquisition device (6) are connected to the host computer (9);

[0038] When the platform is working, the host computer sends a command to the oscillation wave signal injection device (7), the oscillation wave signal injection device (7) generates an oscillation wave signal, and injects the signal into the neutral point (3) of the transformer winding through the input bushing (5). The oscillation wave signal acquisition device (6) acquires the oscillation wave response signal and the oscillation wave injection signal of the transformer winding (2) connected to the output bushing (4), and sends them to the host computer (8). The transformer winding (2) connected to the output winding (4) can be any one of the three phases A, B, and C.

[0039] Step 2: The host computer generates a sequence of collected data

[0040] The host computer serializes the collected voltage signal according to the collection time, with the time unit being microseconds and the voltage unit being volts, and generates a voltage signal sequence related to the collection time and a sequence related to the collection time: v n ,n=0,1,2,……and t n ,n=0,1,2,……;

[0041] Step 3: Calculate the parameters

[0042] Calculate the parameter α according to formula (1):

[0043]

[0044] Where t 2x , t 1x are the two moments when the normal winding has a peak under the oscillation wave, v 2x 、v 1x For normal winding at t 2x , t 1x The corresponding peak value, t2, t1 are the two moments when the winding peak appears under the oscillation wave, v2, v1 are the peak values ​​of the winding at t2, t1, v n is the collected oscillation wave voltage sequence, v xn is the oscillating wave voltage sequence of the normal winding, t n and t xn is the corresponding time series;

[0045] Calculate the parameter β according to formula (2):

[0046]

[0047] Where v n is the collected oscillation wave voltage sequence, v xn is the oscillating wave voltage sequence of the normal winding, t n and t xn is the corresponding time series;

[0048] Traverse the voltage signal sequence and find the voltage between two adjacent zero crossing points (v n ) and the corresponding time (t n ) sequence, x is the number of data points in the sequence, and the normal parameter s of the transformer under the oscillation wave is calculated according to formula (3): n and the collected oscillation wave parameters s c :

[0049]

[0050] Calculate the parameter γ according to formula (4):

[0051]

[0052] Where s n Normal parameters of transformer under oscillation wave, s c The collected oscillation wave parameters;

[0053] Step 4: Calculate the evaluation factor

[0054] The evaluation factor is calculated according to formula (5):

[0055] H=0.2α+0.1β+0.5γ (5)

[0056] H is the evaluation factor

[0057] Step 5: Use the evaluation factor to evaluate the transformer winding. When H<0.05, there is no short circuit fault between the transformer windings.

[0058] When H≥0.05, a short circuit fault occurs between the transformer windings.

Claims

1. A transformer winding short circuit assessment method based on multi-parameter fusion under oscillation wave, characterized by: The collected transformer winding oscillation wave data is used to calculate multiple parameter values ​​and evaluate the transformer winding inter-pie short circuit fault. The following steps are used to calculate the transformer winding oscillation wave multiple parameter values ​​and evaluate the transformer winding inter-pie short circuit: Step 1: Build a transformer oscillation wave signal acquisition platform to obtain winding oscillation wave data The platform mainly consists of a transformer box (1), a transformer winding (2), a transformer winding neutral point (3), an output bushing (4), an input bushing (5), an oscillation wave signal acquisition device (6), an oscillation wave signal injection device (7), and a host computer platform (8); The oscillation wave signal injection device (7) is connected to the input bushing (5), the input bushing (5) is connected to the neutral point (3) of the transformer winding, the winding (2) is connected to the output bushing (4), the output bushing (4) and the output bushing (5) are connected to the oscillation wave signal acquisition device (6), and the oscillation wave injection device (7) and the oscillation wave signal acquisition device (6) are connected to the host computer (9); When the platform is working, the host computer sends a command to the oscillation wave signal injection device (7), the oscillation wave signal injection device (7) generates an oscillation wave signal, and injects the signal into the neutral point (3) of the transformer winding through the input bushing (5). The oscillation wave signal acquisition device (6) acquires the oscillation wave response signal and the oscillation wave injection signal of the transformer winding (2) connected to the output bushing (4), and sends them to the host computer (8). The transformer winding (2) connected to the output winding (4) can be any one of the three phases A, B, and C. Step 2: The host computer generates a sequence of collected data The host computer serializes the collected voltage signal according to the collection time, with the time unit being microseconds and the voltage unit being volts, and generates a voltage signal sequence related to the collection time and a sequence related to the collection time: v n ,n=0,1,2,……and t n ,n=0,1,2,……; Step 3: Calculate the parameters Calculate the parameter α according to formula (1): Where t 2x , t 1x are the two moments when the normal winding has a peak under the oscillation wave, v 2x 、v 1x For normal winding at t 2x , t 1x The corresponding peak value, t2, t1 are the two moments when the winding peak appears under the oscillation wave, v2, v1 are the peak values ​​of the winding at t2, t1, v n is the collected oscillation wave voltage sequence, v xn is the oscillating wave voltage sequence of the normal winding, t n and t xn is the corresponding time series; Calculate the parameter β according to formula (2): Where v n is the collected oscillation wave voltage sequence, v xn is the oscillating wave voltage sequence of the normal winding, t n and t xn is the corresponding time series; Traverse the voltage signal sequence and find the voltage between two adjacent zero crossing points (v n ) and the corresponding time (t n ) sequence, x is the number of data points in the sequence, and the normal parameter s of the transformer under the oscillation wave is calculated according to formula (3): n and the collected oscillation wave parameters s c : Calculate the parameter γ according to formula (4): Where s n Normal parameters of transformer under oscillation wave, s c The collected oscillation wave parameters; Step 4: Calculate the evaluation factor The evaluation factor is calculated according to formula (5): H=0.2α+0.1β+0.5γ (5) H is the evaluation factor Step 5: Evaluate the transformer winding using evaluation factors When H<0.05, there is no short circuit fault between the transformer windings. When H≥0.05, a short circuit fault occurs between the transformer windings.

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