Voltage transformation system and transformer open-phase detection method thereof

Abstract

The invention discloses a transformation system and a transformer open-phase detection method thereof, and relates to the technical field of transformer open-phase detection. The transformation system comprises at least one wire inlet part and a plurality of transformers; each transformer is correspondingly and electrically connected with the wire inlet part; the transformer open-phase detection method of the transformation system comprises the following steps: acquiring a preset open-phase current parameter of a transformer; when a preset square wave signal is injected into the wire inlet part, acquiring a current signal of each transformer neutral point in real time; and determining a current open-phase detection result of the transformer according to the current current signal of the neutral point of the transformer and a preset open-phase current parameter. According to the technical scheme, the preset square wave signal is injected into the transformer, so that the current open-phase detection result of the transformer can be determined according to the current current signal of the neutral point of the transformer and the preset open-phase current parameter, the accuracy of the open-phase detection of the transformer is improved, and the safety and stability of a transformation system are enhanced.

Description

Technical Field

[0001] The embodiments of the present invention relate to a transformer phase failure detection technology, and more particularly to a transformer system and a transformer phase failure detection method thereof. Background Art

[0002] In recent years, transformer phase failures, a common power system failure, have frequently occurred at nuclear power plants worldwide, posing a serious threat to the stable operation of power systems. Within a nuclear power plant's transformer system, transformer phase failures can cause a loss of power to the auxiliary power system, leading to motor tripping, failure of emergency diesel engines to start automatically, shutdown of the reactor, and even temporary loss of core cooling, severely compromising the plant's safety and stability.

[0003] Existing technologies typically rely on traditional electrical relay protection devices or injecting low-frequency current signals into the transformer's neutral point to monitor transformer phase failure. However, when the transformer is operating under no-load or light-load conditions, the changes in electrical quantities caused by a phase failure are minimal, making it difficult for these methods to accurately detect the presence of a phase failure. This results in insufficient sensitivity and accuracy in transformer phase failure detection, making it prone to missed detections or misjudgments. Summary of the Invention

[0004] The present invention provides a transformer system and a transformer phase failure detection method thereof, so as to improve the accuracy of transformer phase failure detection, thereby enhancing the safety and stability of the transformer system.

[0005] A first aspect of the present invention provides a method for detecting a phase failure of a transformer in a transformer system, wherein the transformer system includes at least one incoming line unit and a plurality of transformers; each of the transformers is electrically connected to the incoming line unit. The method for detecting a phase failure of a transformer in the transformer system includes:

[0006] Obtaining a preset open-phase current parameter of the transformer;

[0007] When a preset square wave signal is injected into the incoming line, a current signal of the neutral point of each transformer is obtained in real time;

[0008] The current open phase detection result of the transformer is determined according to the current current signal of the neutral point of the transformer and the preset open phase current parameter.

[0009] Optionally, the preset open-phase current parameter includes a preset open-phase current and a preset open-phase duration; and obtaining the preset open-phase current parameter of the transformer includes:

[0010] Construct a transformer phase failure circuit simulation model;

[0011] Injecting the preset square wave signal into the transformer open phase circuit simulation model, and obtaining a response current signal output by the transformer open phase circuit simulation model;

[0012] The preset phase-off current and the preset phase-off duration are determined according to the response current signal.

[0013] Optionally, the transformer phase failure circuit simulation model includes: a signal injection port, a first resistor, a second resistor, a first capacitor, a first inductor, a first switch, and a current probe;

[0014] The signal injection port is electrically connected between a first end of the first resistor and a second end of the first resistor; the second end of the first resistor and the first end of the first capacitor are electrically connected to the first end of the second resistor respectively; the first end of the first inductor is electrically connected to the second end of the second resistor; the second end of the first inductor and the second end of the first capacitor are both grounded; the current probe is arranged between the second end of the first capacitor and the second end of the first inductor; and the first switch is arranged between the signal injection port and the first end of the first resistor;

[0015] The difference between the resistance value of the first resistor and the line resistance value between the transformer and the corresponding electrically connected incoming line part is within a first preset range; the difference between the resistance value of the second resistor and the winding resistance value of the transformer is within a second preset range; the difference between the capacitance value of the first capacitor and the ground capacitance value of the transformer is within a third preset range; and the difference between the inductance value of the first inductor and the inductance value of the transformer is within a fourth preset range.

[0016] Optionally, injecting the preset square wave signal into the transformer phase failure circuit simulation model and acquiring a response current signal output by the transformer phase failure circuit simulation model includes:

[0017] When the preset square wave signal is injected into the signal injection port and the first switch is closed, obtaining a first current signal between the second end of the first capacitor and the second end of the first inductor in real time based on the current probe, and determining a peak current in the first current signal as a first response current;

[0018] When the preset square wave signal is injected into the signal injection port and the first switch is disconnected, a second current signal between the second end of the first capacitor and the second end of the first inductor is acquired in real time based on the current probe, and a peak current in the second current signal is determined as a second response current.

[0019] Optionally, determining the preset open-phase current according to the response current signal includes:

[0020] An average value of the first response current and the second response current is determined as the preset open-phase current.

[0021] Optionally, determining the preset phase-out duration according to the response current signal includes:

[0022] determining a duration during which the first current signal reaches a first preset percentage of the first response current as a first duration;

[0023] The preset phase-out duration is determined according to the first duration.

[0024] Optionally, determining a current phase failure detection result of the transformer according to a current current signal of the neutral point of the transformer and the preset phase failure current parameter includes:

[0025] When a current signal less than or equal to a preset open-phase current exists in the current signal of the neutral point of the transformer, obtaining a duration during which the current signal of the neutral point of the transformer is less than or equal to the preset open-phase current;

[0026] When the duration is greater than or equal to the preset phase-off duration, it is determined that the transformer is currently in a phase-off state.

[0027] Optionally, the transformer system further includes at least one busbar and at least one circuit breaker; each transformer is electrically connected to the incoming line portion via the busbar; a first end of the circuit breaker is electrically connected to the busbar, and a second end of the circuit breaker is electrically connected to at least one transformer; and the transformer phase failure detection method of the transformer system further includes:

[0028] When at least one of the plurality of transformers is in a phase-off state, the fault state of the transformer system is determined based on the at least one transformer in the phase-off state.

[0029] Optionally, when at least one of the plurality of transformers is in a phase-failed state, determining the fault state of the transformer system according to the at least one transformer in the phase-failed state includes:

[0030] When one of the plurality of transformers connected to the same circuit breaker is in a phase-off state, determining that a fault exists between the transformer in the phase-off state and the circuit breaker connected thereto;

[0031] When all the transformers connected to the same circuit breaker are in a phase-off state and any other transformers are in a non-phase-off state, determining that a fault exists between the circuit breaker and the busbar connected thereto;

[0032] When the number of the transformers connected to the same busbar that are in a phase-out state reaches a preset number, it is determined that a fault exists between the busbar and the incoming line portion connected thereto.

[0033] Optionally, the transformer system further includes an alarm device; and the transformer phase failure detection method of the transformer system further includes:

[0034] When it is determined that the duration of the phase-off state of the transformer is greater than or equal to the preset phase-off duration, the alarm device is controlled to output an alarm signal.

[0035] A second aspect of the present invention provides a voltage transformation system, the voltage transformation system comprising: at least one incoming line unit, a plurality of transformers, and a controller;

[0036] Each of the transformers is electrically connected to the line input portion respectively;

[0037] The controller is electrically connected to the incoming line and each transformer, and is used to execute the transformer phase failure detection method of the transformer system as described above.

[0038] The technical solution of the present invention obtains the preset phase-break current parameters of the transformer to provide a clear judgment benchmark for the current signal at the neutral point of the transformer, thereby laying the foundation for the subsequent judgment of whether the transformer has a phase break. At the same time, by injecting a preset square wave signal into the incoming line, the current signal of the neutral point of each transformer is obtained in real time, so that the current phase break detection result of the transformer can be determined based on the current current signal of the neutral point of the transformer and the preset phase-break current parameters. When a phase break state exists in the transformer, the transformer's response ability to the preset square wave signal decreases, resulting in a significant reduction in the amplitude of the current signal output by the neutral point of the transformer, that is, the current peak value in the current signal of the neutral point of the transformer is significantly reduced. Therefore, by obtaining the current signal of the neutral point of each transformer in real time and comparing it with the preset phase-break current parameters, the current phase break state of each transformer can be accurately detected, thereby improving the accuracy of transformer phase break detection and enhancing the safety and stability of the transformer system.

[0039] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 1 is a schematic structural diagram of a voltage conversion system provided in Embodiment 1 of the present invention;

[0042] Figure 2 1 is a flow chart of a method for detecting a phase failure in a transformer of a transformer system provided by a second embodiment of the present invention;

[0043] Figure 3 1 is a flow chart of a method for detecting a phase failure in a transformer of a transformer system provided by a third embodiment of the present invention;

[0044] Figure 4 This is a schematic structural diagram of a transformer phase failure circuit simulation model provided by the third embodiment of the present invention;

[0045] Figure 5 1 is a flow chart of a method for detecting a phase failure in a transformer of a transformer system provided by a fourth embodiment of the present invention;

[0046] Figure 6 1 is a schematic structural diagram of a transformer phase failure detection device for a transformer system provided by a fifth embodiment of the present invention;

[0047] Figure 7 This is a structural diagram of a controller of a transformer system provided in Example 6 of the present invention. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0049] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0050] Example 1

[0051] Figure 1 This is a schematic diagram of the structure of a transformer system provided by the first embodiment of the present invention. Figure 1As shown, the transformer system includes at least one incoming line unit 1 and a plurality of transformers 2; each transformer 2 is electrically connected to the incoming line unit 1 respectively.

[0052] Specifically, the incoming line section 1 can be understood as the auxiliary transformer high-voltage side incoming line section, which is used to receive high-voltage electrical signals from an external power source and input them into the high-voltage side of each transformer 2 via a cable. This allows the transformer 2 to convert the high-voltage electrical signals transmitted by the incoming line section 1 into low-voltage electrical signals through its internal windings, and then distribute the converted low-voltage electrical signals to the auxiliary load end of the nuclear power plant through the low-voltage side of the transformer 2 to ensure the normal operation of the auxiliary equipment of the nuclear power plant. For example, the incoming line section 1 may include 200kV overhead lines, cable bushings, and gas-insulated switchgear (GIS); the auxiliary load end of the nuclear power plant may include cooling water pumps, ventilation systems, lighting systems, and motor drive equipment.

[0053] The high-voltage side of transformer 2 can adopt a star (Y-type) connection, comprising three phases (A, B, and C), with one winding for each phase. The neutral point of the high-voltage side of transformer 2 is grounded, thus maintaining a fixed relative ground position for the three-phase voltages and forming a stable voltage reference point. Specifically, each transformer 2 is electrically connected to a corresponding incoming line unit 1. Incoming line unit 1 can be connected to a square wave signal output device to inject a square wave signal into the high-voltage side of the correspondingly connected transformer 2. A square wave signal can be understood as a high-frequency rectangular wave with sharp rising and falling edges and rich high-frequency harmonic components. For example, the voltage of the square wave signal can be 20V, and the frequency of the square wave signal can be 10kHz. Upon receiving the square wave signal, the high-voltage side of transformer 2 converts the square wave signal and outputs a current response waveform through the neutral point. It is understood that the winding resistance within transformer 2 causes current attenuation, while the filtering effect of the inductor and capacitor within transformer 2 smoothes the sharp edges of the square wave signal. Therefore, the current response waveform output from the neutral point of the transformer will exhibit an oscillating decay waveform or a quasi-sinusoidal waveform. It can also be understood that when the three phases on the high-voltage side of transformer 2 are intact, the square wave signal will be evenly distributed among the three phases of transformer 2, and the current peak value in the current response waveform output from the neutral point is relatively high. When a phase failure occurs on the high-voltage side of transformer 2, such as when phase A is disconnected, this will result in three-phase imbalance, and the transformer 2's ability to respond to high-frequency square waves will decrease, resulting in a significant decrease in the amplitude of the current response waveform output from the neutral point, i.e., a significant decrease in the current peak value in the current response waveform. Therefore, by injecting a square wave signal into the high-voltage side of transformer 2 through the incoming line 1 and obtaining the peak current in the current response waveform output from the neutral point of the high-voltage side of transformer 2 through a current detection device, such as a current transformer, the phase failure state of transformer 2 can be accurately detected, thereby improving the accuracy of transformer phase failure detection and enhancing the safety and stability of the transformer system. In addition, the square wave signal output device can output a square wave signal once every certain time interval, and the square wave signal output each time lasts for the test time. The interval time and the duration of the square wave signal can be determined according to actual needs, and the present invention does not make specific limitations on this.

[0054] Optionally, the transformer system also includes at least one busbar 3 and at least one circuit breaker 4; each transformer 2 is electrically connected to the incoming line part 1 through the busbar 3; the first end of the circuit breaker 4 is electrically connected to the busbar 3, and the second end of the circuit breaker 4 is electrically connected to at least one transformer 2.

[0055] Specifically, the busbar 3 can be understood as a conductor used to collect, distribute, and transmit electrical energy in the transformer system. The busbar 3 is electrically connected to the incoming line unit 1 and each transformer 2, respectively, so that the busbar 3 can distribute the square wave signal injected by the incoming line unit 1 to each of the multiple transformers 2. When multiple busbars 3 are provided in the transformer system, namely, a first busbar 31 and a second busbar 32, each transformer 2, namely, the first transformer 21, the second transformer 22, the third transformer 23, and the fourth transformer 24, can switch the busbar 3 to which it is connected according to actual operating requirements, thereby enhancing the power supply flexibility and reliability of the transformer system. Exemplarily, when the first isolating switch QS1 and the third isolating switch QS3 are closed, and the second isolating switch QS2 and the fourth isolating switch QS4 are opened, the first transformer 21, the second transformer 22, the third transformer 23 and the fourth transformer 24 are all electrically connected to the first bus 31; when the first isolating switch QS1 and the third isolating switch QS3 are opened, and the second isolating switch QS2 and the fourth isolating switch QS4 are closed, the first transformer 21, the second transformer 22, the third transformer 23 and the fourth transformer 24 are all electrically connected to the second bus 32.

[0056] A first end of the circuit breaker 4 is electrically connected to the busbar 3, and a second end of the circuit breaker 4 is electrically connected to at least one transformer 2, so that the connection between the transformer 2 and the busbar 3 can be cut off or connected through the circuit breaker 4. In this way, the number of transformers 2 connected to the busbar 3 can be adjusted according to the needs of the auxiliary load end of the nuclear power plant, thereby optimizing power distribution. In addition, when there is a transformer in the phase-off state among the transformers 2, the connection between the transformer in the phase-off state and the busbar 3 can be promptly cut off, thereby avoiding further expansion of the fault. Exemplarily, when there are multiple circuit breakers 4 in the transformer system, namely, a first circuit breaker 41 and a second circuit breaker 42, the first end of the first circuit breaker 41 is electrically connected to the busbar 3, the second end of the first circuit breaker 41 is electrically connected to the first transformer 21 and the second transformer 22 respectively, the first end of the second circuit breaker 42 is electrically connected to the busbar 3, and the second end of the first circuit breaker 42 is electrically connected to the third transformer 23 and the fourth transformer 24 respectively, so that the connection between the first transformer 21 and the second transformer 22 and the busbar 3 can be cut off or connected through the first circuit breaker 41, and the connection between the third transformer 23 and the fourth transformer 24 and the busbar 3 can be cut off or connected through the second circuit breaker 42.

[0057] The circuit breaker 4 may further include a third circuit breaker 43, a first end of the third circuit breaker 43 being electrically connected to the incoming line portion 1, a second end of the third circuit breaker 43 being electrically connected to the busbar 31 and the busbar 32 respectively, and a fifth isolating switch QS5 being provided between the second end of the third circuit breaker 43 and the busbar 31, and a sixth isolating switch QS6 being provided between the second end of the third circuit breaker 43 and the busbar 32, so that the connection between the incoming line portion 1 and the busbar 31 and the busbar 32 can also be controlled by the third circuit breaker 43, the fifth isolating switch QS5 and the sixth isolating switch QS6. For example, when the third circuit breaker 43 is turned on, the fifth isolating switch QS5 is closed, and the sixth isolating switch QS6 is opened, the lead portion 1 can be electrically connected to the bus 31, so that the square wave signal injected by the lead portion 1 can be output to the transformer 2 through the bus 31; when the third circuit breaker 43 is turned on, the fifth isolating switch QS5 is opened, and the sixth isolating switch QS6 is closed, the lead portion 1 can be electrically connected to the bus 32, so that the square wave signal injected by the lead portion 1 can be output to the transformer 2 through the bus 32. Furthermore, when the transformer system includes multiple incoming line sections 1, namely, a first incoming line section 11 and a second incoming line section 12, a fourth circuit breaker 44, a seventh disconnector QS7, and an eighth disconnector QS8 may be provided between the second incoming line section 12 and the busbar 3, respectively. This allows the third circuit breaker 43, the fourth circuit breaker 44, the fifth disconnector QS5, the sixth disconnector QS6, the seventh disconnector QS7, and the eighth disconnector QS8 to be controlled on and off to adjust the electrical connections of the lead sections 1 to the busbars 31 and 32, respectively. When the transformer system includes multiple busbars 3 and multiple incoming line sections 1, with each busbar 3 electrically connected to each incoming line section 1, a corresponding square wave signal output device may be provided for each incoming line section 1. Different square wave signal output devices may output square wave signals for only a certain test duration and at predetermined intervals, thereby preventing signal reflections from affecting the test results.

[0058] By separately controlling the connection between the lead-in device and the busbar, and the connection between the busbar and the transformer, efficient distribution and flexible switching of electricity are achieved, improving the flexibility and reliability of electrical signal transmission in the transformer system.

[0059] It can also be understood that, after a square wave signal is injected into the high-voltage side of the transformer 2 through the incoming line 1 and the peak current in the current response waveform output from the neutral point of the transformer 2 is obtained to determine the phase-off state of the transformer 2, the fault state of the transformer system can also be determined by the transformer 2 in the phase-off state. For example, when the first transformer 21 and the second transformer 22 connected to the first circuit breaker 41 are in the phase-off state and the second transformer 22 is in the non-phase-off state, it can be determined that a fault exists between the first transformer 21 and the first circuit breaker 41; when the first transformer 21 and the second transformer 22 connected to the first circuit breaker 41 are both in the phase-off state and the third transformer 23 and the fourth transformer 24 connected to the second circuit breaker 42 are both in the non-phase-off state, it can be determined that a fault exists between the first circuit breaker 41 and the bus 3 connected thereto; when the first transformer 21, the second transformer 22, the third transformer 23, and the fourth transformer 24 connected to the bus 31 are all in the phase-off state, it can be determined that a fault exists between the bus 31 and the incoming line 1 connected thereto. By determining the specific circumstances of the fault in the transformer system based on the condition of the transformer in a phase-out state, it is possible to ensure the safe and reliable operation of the nuclear power plant while effectively improving the speed of fault detection and maintenance efficiency.

[0060] Optionally, the transformer control system may further include an alarm device. Exemplarily, the alarm device may include an audible alarm device, an optical alarm device, and a remote communication alarm device. The alarm device is configured to output an alarm signal when it is determined that the duration of the transformer phase failure is greater than or equal to a preset phase failure duration, thereby reminding the operator to promptly address the transformer phase failure, thereby preventing further expansion of the fault in the transformer system, improving the safety and maintenance efficiency of the nuclear power plant transformer system, and ensuring the reliable operation of the nuclear power plant transformer system.

[0061] In addition, the transformer system also includes a controller 5, which is electrically connected to the incoming line unit 1 and each transformer 2. Exemplarily, the controller may include a microcontroller unit (MCU), a digital signal processing chip (DSP), a field programmable gate array (FPGA), and a system-on-chip (SOC). It is understood that the controller 5 in the transformer system can execute the transformer phase loss detection method for the transformer system provided in the embodiments of the present invention and has the corresponding functional modules and beneficial effects of executing the method. For technical details not fully described in this embodiment, please refer to the transformer phase loss detection method for the transformer system described in the embodiments below.

[0062] Example 2

[0063] Figure 2 This is a flow chart of a transformer phase failure detection method for a transformer system provided by the second embodiment of the present invention. This embodiment can be used to control the transformer system of the above embodiment. The method can be executed by a transformer phase failure detection device for the transformer system. The device can be implemented by software and / or hardware and can generally be integrated into the controller of the transformer system. Figure 2 As shown, the transformer phase failure detection method of the transformer system may include:

[0064] S101: Obtain preset open-phase current parameters of the transformer.

[0065] Specifically, to determine the transformer phase failure detection result based on the transformer neutral point current signal, it is first necessary to determine a preset phase failure current parameter, thereby providing a clear judgment benchmark for the transformer neutral point current signal. This preset phase failure current parameter is used to compare with the actual transformer neutral point current signal to determine whether the transformer has a phase failure. Exemplarily, the preset phase failure current parameter may include a preset phase failure current and a preset phase failure duration. The preset phase failure current can be specifically understood as a current threshold for the transformer neutral point current signal when the transformer is in a normal state, used to determine whether the current current signal at the transformer neutral point is lower than the neutral point current value when the transformer is in a normal state. The preset phase failure duration can be specifically understood as a threshold for the duration that the transformer neutral point current signal is lower than the normal current value, used to determine the persistence of the transformer phase failure state, thereby avoiding misjudgment. The preset phase failure current parameter can be determined based on a transformer phase failure circuit simulation model or based on historical current data of the transformer neutral point in normal and phase failure states in the nuclear power plant transformer system, etc., which is not specifically limited in the present invention.

[0066] S102 . When a preset square wave signal is injected into the incoming line, the current signal of the neutral point of each transformer is obtained in real time.

[0067] Specifically, the controller can inject a preset square wave signal into the incoming line, so as to inject the preset square wave signal into the transformer through the incoming line and the busbar in turn. The square wave signal can be specifically understood as a high-frequency rectangular wave with a steep rising edge and falling edge, and contains rich high-frequency harmonic components. For example, the voltage of the square wave signal can be 20V, and the frequency of the square wave signal can be 10kHZ. When the transformer receives the square wave signal, it converts the square wave signal and outputs the current signal through the neutral point. It can be understood that the winding resistance inside the transformer will cause the current to attenuate. At the same time, the filtering effect of the inductance and capacitance inside the transformer will smooth the steep edges of the square wave signal. Therefore, the current signal output from the neutral point will present an oscillating attenuated waveform or a quasi-sinusoidal waveform, thereby laying the foundation for the subsequent acquisition of the current signal of the neutral point of the transformer and determination of the phase failure detection result of the transformer.

[0068] After injecting a preset square wave signal into the transformer, the controller can obtain the current signal of the transformer's neutral point in real time through a current detection device, such as a current transformer, so as to determine the transformer's phase failure detection result by comparing the current current signal of the neutral point with the preset phase failure current parameter. It can be understood that when the three phases of the transformer are complete, the preset square wave signal will be evenly distributed among the three phases. At this time, the current peak value in the current signal output from the transformer's neutral point is higher; when there is a phase failure state in the transformer, such as when phase A is disconnected, it will cause three-phase imbalance, and the transformer's ability to respond to high-frequency square waves will decrease, resulting in a significant reduction in the amplitude of the current signal output from the transformer's neutral point, that is, a significant reduction in the current peak value in the neutral point current signal. Therefore, by obtaining the current signal of each transformer's neutral point in real time, the phase failure state of each transformer can be accurately detected, thereby improving the accuracy of transformer phase failure detection and enhancing the safety and stability of the transformer system.

[0069] S103: Determine a current phase failure detection result of the transformer according to a current current signal of the neutral point of the transformer and a preset phase failure current parameter.

[0070] Specifically, after obtaining the current current signal of the neutral point of the transformer, the controller can determine the phase loss detection result of the transformer by comparing the current current signal of the neutral point of the transformer with the preset phase loss current parameter to improve the accuracy of the transformer phase loss detection.

[0071] Optionally, the current phase-failure detection result of the transformer is determined based on the current current signal of the transformer neutral point and the preset phase-failure current parameter, including: when there is a current signal less than or equal to the preset phase-failure current in the current signal of the transformer neutral point, obtaining the duration of the current signal of the transformer neutral point being less than or equal to the preset phase-failure current; when the duration is greater than or equal to the preset phase-failure duration, determining that the transformer is currently in a phase-failure state.

[0072] Specifically, the preset phase-break parameters include a preset phase-break current and a preset phase-break duration. When a current signal less than or equal to the preset phase-break current exists in the current signal of the transformer neutral point, it indicates that the current signal of the transformer neutral point is lower than the current threshold of the current signal output by the neutral point when the transformer is in a normal state, that is, there is a phase break in the transformer at this time. At the same time, the controller will obtain the duration of the neutral point current signal of the transformer with a phase break being less than or equal to the preset phase-break current to determine the duration of the transformer being in the phase-break state. When the duration is greater than or equal to the preset phase-break duration, it indicates that the transformer is continuously in the phase-break state. Therefore, the controller determines that the transformer is currently in the phase-break state, thereby avoiding misjudgment caused by instantaneous interference or noise and ensuring the reliability of the transformer phase-break detection result.

[0073] This embodiment obtains the preset phase-break current parameters of the transformer to provide a clear judgment benchmark for the current signal at the transformer's neutral point, thereby laying the foundation for subsequent judgment of whether the transformer has a phase break. At the same time, by injecting a preset square wave signal into the incoming line, the current signal at the neutral point of each transformer is obtained in real time, so that the current phase break detection result of the transformer can be determined based on the current current signal at the transformer's neutral point and the preset phase-break current parameters. When a phase break occurs in the transformer, the transformer's responsiveness to the preset square wave signal decreases, resulting in a significant decrease in the amplitude of the current signal output by the transformer's neutral point, that is, a significant decrease in the current peak value in the transformer's neutral point current signal. Therefore, by obtaining the current signal at the neutral point of each transformer in real time and comparing it with the preset phase-break current parameters, the current phase break state of each transformer can be accurately detected, thereby improving the accuracy of transformer phase break detection and enhancing the safety and stability of the transformer system.

[0074] Example 3

[0075] Figure 3 This is a flow chart of a method for detecting a phase failure in a transformer system according to a third embodiment of the present invention. Based on the above embodiment, this embodiment describes in detail a method for obtaining a preset phase failure current parameter of a transformer. Figure 3 As shown, the transformer phase failure detection method of the transformer system of this embodiment may include:

[0076] S201. Construct a transformer phase failure circuit simulation model.

[0077] Specifically, in order to obtain the preset phase-off current parameters of the transformer, a transformer phase-off circuit simulation model can be constructed. Thus, the transformer phase-off circuit simulation model can simulate the current signals of the transformer neutral point corresponding to the transformer being in the phase-off state and the transformer being in the normal state when the preset square wave signal is injected into the transformer, thereby determining the preset phase-off current and the preset phase-off duration. Exemplary methods of constructing the transformer phase-off circuit simulation model may include modeling according to relevant parameters of the transformer system input by the user end and preset rules, or communicating with the control end of the nuclear power plant transformer system through a controller to obtain its relevant parameters and modeling the corresponding transformer phase-off circuit simulation model locally or in the cloud according to preset rules.

[0078] Optional, Figure 4 : is a schematic diagram of a transformer phase failure circuit simulation model provided by the third embodiment of the present invention. Figure 4 As shown, the transformer phase failure circuit simulation model includes: a signal injection port A, a first resistor R1, a second resistor R2, a first capacitor C1, a first inductor L1, a first switch K1 and a current probe B; the signal injection port A is electrically connected between the first end of the first resistor R1 and the second end of the first resistor R1; the second end of the first resistor R1 and the first end of the first capacitor C1 are electrically connected to the first end of the second resistor R2 respectively; the first end of the first inductor C1 is electrically connected to the second end of the second resistor R2; the second end of the first inductor L1 and the second end of the first capacitor C1 are both grounded; the current probe B is set at the first between the second end of a capacitor C1 and the second end of a first inductor L1; a first switch K1 is arranged between a signal injection port A and a first end of a first resistor R1; a difference between a resistance value of the first resistor R1 and a line resistance value between a transformer and a corresponding incoming line portion electrically connected thereto is within a first preset range; a difference between a resistance value of the second resistor R2 and a winding resistance value of the transformer is within a second preset range; a difference between a capacitance value of the first capacitor C1 and a capacitance value of the transformer to ground is within a third preset range; and a difference between an inductance value of the first inductor L1 and an inductance value of the transformer is within a fourth preset range.

[0079] Signal injection port A is used to inject a preset square wave signal into first resistor R1, so that the preset square wave signal can be processed by an equivalent circuit consisting of first resistor R1, second resistor R2, first capacitor C1, and first inductor L1, and a response current signal is output through the equivalent circuit. Current probe B is used to obtain the response current signal output by the transformer phase-failure circuit simulation model, thereby analyzing the difference in the current signal at the transformer neutral point when the transformer is in a normal state and in a phase-failure state.

[0080] Specifically, the difference between the resistance of the first resistor R1 and the line resistance between the transformer and the corresponding electrically connected incoming line portion is within a first preset range, so that the line resistance between the transformer and the corresponding electrically connected incoming line portion, that is, the transmission path resistance from the incoming line portion to the transformer, can be simulated through the first resistor R1. Exemplarily, the resistance of the first resistor R1 can be 0.3Ω. The line resistance between the incoming line portion and the transformer will affect the attenuation of the preset square wave signal during transmission in the transformer system. The setting of the first resistor R1 ensures that the transformer phase failure circuit simulation model is close to the actual transformer system. The signal injection port A is electrically connected between the first end of the first resistor R1 and the second end of the first resistor R1, so that the controller can inject a preset square wave signal into the first resistor R1 through the signal injection port A, thereby simulating the process of injecting a preset square wave signal into the transformer through the incoming line portion in an actual transformer system. After passing through the first resistor R1, the preset square wave signal will enter the subsequent transformer equivalent circuit, thereby generating a response current signal.

[0081] The transformer equivalent circuit includes a second resistor R2, a first capacitor C1, and a first inductor L1. The difference between the resistance of the second resistor R2 and the resistance of the transformer winding is within a second preset range, so that the copper loss resistance of the transformer winding is simulated by the second resistor R2. The second resistor R2 reflects the resistance loss of the transformer winding. Exemplarily, the resistance of the second resistor R2 can be 0.3Ω. The difference between the capacitance of the first capacitor C1 and the ground capacitance of the transformer is within a third preset range, so that the first capacitor C1 can simulate the ground capacitance of the transformer, that is, the parasitic capacitance between the transformer winding and the ground terminal. This parasitic capacitance affects the distribution of high-frequency signals. Exemplarily, the capacitance of the first capacitor C1 can be 67nF. The difference between the inductance of the first inductor L1 and the inductance of the transformer is within a fourth preset range, so that the first inductor L1 can simulate the inductance characteristics of the transformer. This inductance characteristic is used to reflect the magnetic circuit characteristics and leakage inductance effect. Exemplarily, the inductance value of the first inductor L1 can be 9mH. After the preset square wave signal enters the transformer equivalent circuit, the second resistor R2 will cause the current to decay, the first capacitor C1 will smooth the high-frequency peaks of the preset square wave signal, generating an oscillating component, and the first inductor L1 will delay the current change of the preset square wave signal, generating a smoothing component, and finally forming a neutral point current response waveform through the transformer equivalent circuit. The neutral point current response waveform will present an oscillating attenuation waveform or a quasi-sinusoidal waveform.

[0082] It can be understood that, under the premise of ensuring that the transformer phase-failure circuit simulation model can simulate the current signal of the transformer neutral point corresponding to the transformer being in a phase-failure state and the transformer being in a normal state when a preset square wave signal is injected into the transformer, the first preset range, the second preset range, the third preset range and the fourth preset range can be determined according to actual needs, and the embodiment of the present invention does not make specific limitations on this.

[0083] The second end of the first capacitor C1 and the second end of the first inductor L1 are both grounded, thereby forming a neutral point, and the current probe B can obtain the response current signal output between the second end of the first capacitor C1 and the second end of the first inductor L1. The first switch K1 is set between the signal injection port A and the first end of the first resistor R1, and is used to simulate the normal state and the phase-off state of the transformer. Exemplarily, when the first switch K1 is closed, the transformer phase-off circuit simulation model can simulate the normal state of the transformer, and the preset square wave signal is normally injected, so that the current probe B can obtain the response current signal output by the neutral point when the transformer is in the normal state; when the first switch K1 is disconnected, the transformer phase-off circuit simulation model can simulate the phase-off state of the transformer, and the preset square wave signal cannot be normally injected, so that the current probe B can obtain the response current signal output by the neutral point when the transformer is in the phase-off state.

[0084] In addition, the signal injection port A may include a first signal injection port A1 and a second signal injection port A2, so that the controller can control the first signal injection port A1 and the second signal injection port A2 to alternately inject a preset square wave signal into the first resistor R1 at a preset time interval. For example, the preset time interval may include 10 minutes to prevent the test results from being affected by signal reflection. In this way, the first signal injection port A1 and the second signal injection port A2 can simulate the situation in which a preset square wave signal is alternately injected into the transformer through multiple buses at a preset time interval in a transformer system, so that the circuit simulation model is more consistent with the actual operating state of the transformer system, thereby improving the adaptability and reliability of transformer phase loss detection. It can also be understood that when the signal injection port A includes a first signal injection port A1 and a second signal injection port A2, the current probe B will correspondingly include a first current probe B1 and a second current probe B2, and each signal injection port A and each current probe B are set in a one-to-one correspondence, that is, when a preset square wave signal is injected into the first resistor R1 through the first signal injection port A1, a response current signal is obtained through the first current probe B1, and when a preset square wave signal is injected into the first resistor R1 through the second signal injection port A2, a response current signal is obtained through the second current probe B2, so as to avoid mutual interference between signals and ensure that the detection of each transformer phase failure detection circuit is performed independently.

[0085] S202: Inject a preset square wave signal into the transformer phase failure circuit simulation model, and obtain a response current signal output by the transformer phase failure circuit simulation model.

[0086] Specifically, the transformer phase-failure circuit simulation model can be used to simulate transformers in normal and phase-failure states, so that by injecting a preset square wave signal into the transformer phase-failure circuit simulation model, the corresponding output response current signals when the transformer is in normal and phase-failure states can be obtained, thereby laying the foundation for the subsequent determination of the preset phase-failure current and the preset phase-failure duration.

[0087] Optionally, a preset square wave signal is injected into the transformer phase-failure circuit simulation model, and a response current signal output by the transformer phase-failure circuit simulation model is obtained, including: when a preset square wave signal is injected into the signal injection port A and the first switch K1 is closed, a first current signal between the second end of the first capacitor C1 and the second end of the first inductor L1 is obtained in real time based on the current probe B, and the peak current in the first current signal is determined as the first response current; when a preset square wave signal is injected into the signal injection port A and the first switch K1 is opened, a second current signal between the second end of the first capacitor C1 and the second end of the first inductor L1 is obtained in real time based on the current probe B, and the peak current in the second current signal is determined as the second response current.

[0088] Specifically, when the first switch K1 is closed, the transformer phase-failure circuit simulation model can simulate the normal state of the transformer, and the preset square wave signal injected into the first resistor R1 through the signal injection port A can be normally injected, so that the current probe B can obtain the first current signal output by the neutral point when the transformer is in the normal state. At the same time, the controller can determine the peak current in the first current signal as the first response current. The first response current reflects the maximum response current output by the neutral point of the transformer after the preset square wave signal passes through the transformer equivalent circuit when the transformer is in the normal state, providing a basis for subsequent calculation of the preset phase-failure current. When the first switch K1 is open, the transformer phase-failure circuit simulation model can simulate the phase-failure state of the transformer, and the preset square wave signal injected into the first resistor R1 through the signal injection port A cannot be normally injected, so that the current probe B can obtain the second current signal output by the neutral point when the transformer is in the phase-failure state. At the same time, the controller can determine the peak current in the second current signal as the second response current. The second response current reflects the maximum response current output by the neutral point of the transformer after the preset square wave signal passes through the transformer equivalent circuit when the transformer is in the phase-failure state, providing a basis for subsequent calculation of the preset phase-failure current.

[0089] S203: Determine a preset phase-off current and a preset phase-off duration according to the response current signal.

[0090] Specifically, after obtaining the first current signal output by the transformer phase-break circuit simulation model when simulating the normal state of the transformer through the transformer phase-break circuit simulation model, and obtaining the second current signal output by the transformer phase-break circuit simulation model when simulating the phase-break state of the transformer through the transformer phase-break circuit simulation model, the controller will determine the preset phase-break current and the preset phase-break duration based on the first current signal and the second current signal, thereby providing a judgment basis for subsequently determining the current phase-break detection result of the transformer.

[0091] Optionally, determining a preset open-phase current according to the response current signal includes: determining an average value of the first response current and the second response current as the preset open-phase current.

[0092] Specifically, the first response current represents the peak current value of the response current signal output by the transformer neutral point when the transformer is in a normal state, and the second response current represents the peak current value of the response current signal output by the transformer neutral point when the transformer is in a phase-failure state. By setting the preset phase-failure current to the average value of the first response current and the second response current, the neutral point current signal characteristics of the transformer in both normal and phase-failure states are comprehensively considered. This avoids the possibility of misjudging the transformer phase-failure detection by directly using the first response current or the second response current as the preset phase-failure current. For example, using the first response current as the preset phase-failure current may result in an excessively high threshold value, leading to missed detection of the transformer phase-failure state, while using the second response current as the preset phase-failure current may result in an excessively low threshold value, leading to misdetection when the transformer is in a normal state. This improves the accuracy and stability of transformer phase-failure detection. Furthermore, by setting the preset phase-failure current to the average value of the first response current and the second response current, the preset phase-failure current can be applied to a variety of operating scenarios, such as operating scenarios of nuclear power plant transformers under different operating conditions, such as no-load, light-load, or heavy-load. This also reduces the impact of transient interference on transformer phase-failure detection, improving the robustness and accuracy of transformer phase-failure detection.

[0093] Optionally, determining a preset phase-out duration based on the response current signal includes: determining the duration of time for the first current signal to reach a first preset percentage of the first response current as a first duration; and determining the preset phase-out duration based on the first duration.

[0094] Specifically, to determine the preset phase-out duration, the controller first determines the duration of time during which the first current signal reaches a first preset percentage of the first response current as the first duration. For example, the first preset percentage may include 65%, 70%, or 75%. The first duration can be specifically understood as the time it takes for the first current signal to decay from a peak current value to a certain threshold value, such as 70% of the peak current value. This reflects the persistence and stability of the neutral point current waveform when the transformer is in a normal state, providing a basis for subsequently determining the preset phase-out duration and serving as a criterion for confirming the persistence of the transformer's phase-out state. After determining the first duration, the controller can determine the preset phase-out duration based on the first duration. For example, the controller can determine a second preset percentage of the first duration as the preset phase-out duration. The second preset percentage may be, for example, 70%, to increase redundancy in detecting the persistence of the transformer's phase-out state. Thus, the persistence of the transformer's phase-out state can be determined using the preset phase-out duration. If the duration of the transformer's phase-out state is greater than or equal to the preset phase-out duration, it indicates that the transformer is in a persistent phase-out state. By determining the first duration and further determining the preset phase-out duration, the preset phase-out duration determined based on the transformer phase-out circuit simulation model is made to be more in line with the actual current response characteristics of the transformer, thereby avoiding transient interference and improving the accuracy and reliability of transformer phase-out detection.

[0095] S204 , when injecting a preset square wave signal into the incoming line, obtaining the current signal of the neutral point of each transformer in real time.

[0096] S205 : Determine a current phase failure detection result of the transformer according to a current current signal of the neutral point of the transformer and a preset phase failure current parameter.

[0097] In this embodiment, a transformer phase failure circuit simulation model is constructed, and a signal injection port, a first resistor, a second resistor, a first capacitor, a first inductor, a first switch, and a current probe are set in the circuit simulation model. The first resistor can simulate the line resistance between the transformer and the corresponding incoming line portion electrically connected thereto, the second resistor can simulate the copper loss resistance of the transformer winding, the first capacitor can simulate the transformer's capacitance to ground, and the first inductor can simulate the transformer's inductance characteristics. Thus, the transformer phase failure circuit simulation model can simulate the first current signal and the second current signal output from the neutral point of the transformer when a preset square wave signal is injected into the transformer, respectively, corresponding to the transformer being in a normal state and the transformer being in a phase failure state. In addition, by determining the peak current in the first current signal as the first response current and the peak current in the second current signal as the second response current, the average value of the first response current and the second response current can be determined as the preset phase failure current, so that the preset phase failure current can be applied to a variety of operating scenarios, while reducing the impact of transient interference on transformer phase failure detection. At the same time, by determining the duration of the first preset percentage of the first response current in the first current signal as the first duration, and determining the preset phase-out duration based on the first duration, the preset phase-out duration determined based on the transformer phase-out circuit simulation model is more in line with the actual current response characteristics of the transformer, thereby improving the accuracy and reliability of transformer phase-out detection.

[0098] Example 4

[0099] Figure 5 1 is a flow chart of a method for detecting a phase failure of a transformer in a transformer system according to a fourth embodiment of the present invention. This embodiment supplements the method for detecting a phase failure of a transformer in a transformer system based on the above embodiment. Accordingly, Figure 5 As shown, the transformer phase failure detection method of the transformer system of this embodiment may include:

[0100] S301: Obtain preset open-phase current parameters of the transformer.

[0101] S302 : When a preset square wave signal is injected into the incoming line, the current signal of the neutral point of each transformer is obtained in real time.

[0102] S303: Determine a current phase failure detection result of the transformer according to a current current signal of the neutral point of the transformer and a preset phase failure current parameter.

[0103] S304: When at least one transformer among the multiple transformers is in a phase-off state, determine a fault state of the transformer system according to the at least one transformer in the phase-off state.

[0104] Specifically, when it is determined that at least one transformer among multiple transformers is in a phase-failure state based on the current current signal of the transformer neutral point and the preset phase-failure current parameters, the controller can also determine the fault state of the transformer system based on the transformer in the phase-failure state, so as to ensure the safe and reliable operation of the nuclear power plant while effectively improving the speed of fault detection and maintenance efficiency.

[0105] Optionally, when at least one transformer among multiple transformers is in a phase-out state, the fault state of the transformer system is determined based on the at least one transformer in the phase-out state, including: when one of the multiple transformers connected to the same circuit breaker is in a phase-out state, determining that a fault exists between the transformer in the phase-out state and the circuit breaker connected thereto; when all transformers connected to the same circuit breaker are in a phase-out state and any other transformers are in a non-phase-out state, determining that a fault exists between the circuit breaker and the busbar connected thereto; when the number of transformers connected to the same busbar in a phase-out state reaches a preset number, determining that a fault exists between the busbar and the incoming line connected thereto.

[0106] Specifically, because a circuit breaker serves as a common connection point for multiple transformers connected to it, if one of the multiple transformers connected to the same circuit breaker is in a phase-off state and the other transformers connected to the circuit breaker are all in a phase-off state, the controller will determine that a fault exists between the transformer in the phase-off state and the circuit breaker connected to it, such as an abnormal fault in the cable or circuit component between the transformer in the phase-off state and the circuit breaker connected to it. If all transformers connected to the same circuit breaker are in a phase-off state and any other transformers are in a phase-off state, it indicates that electrical signals can be normally transmitted between the busbar connected to the circuit breaker and the incoming line. Therefore, the controller will determine that a fault exists between the circuit breaker and the busbar connected to it, such as an abnormal fault in the cable or circuit component, such as a disconnector, between the busbar and the incoming line. If the number of transformers connected to the same busbar in a phase-off state reaches a preset number, the controller will determine that a fault exists between the busbar and the incoming line, such as an abnormal fault in the cable or circuit component, such as a disconnector, between the busbar and the incoming line. Exemplarily, the preset number can be the number of all transformers connected to the busbar. For example, if four transformers are connected to the busbar, and four of the transformers connected to the busbar are in a phase-out state, this indicates that the fault in the transformer system affects the entire busbar. Therefore, the controller will determine that a fault exists between the busbar and the incoming line connected to it. By analyzing the distribution of transformers in a phase-out state, the fault in the transformer system can be located between the transformer and the circuit breaker connected to it, between the circuit breaker and the busbar connected to it, or between the busbar and the incoming line connected to it, thereby achieving precise fault location, effectively accelerating troubleshooting and improving maintenance efficiency.

[0107] Optionally, the transformer phase failure detection method of the transformer system further includes: when it is determined that the duration of the transformer being in the phase failure state is greater than or equal to a preset phase failure duration, controlling the alarm device to output an alarm signal.

[0108] Specifically, after determining that the transformer is currently in a phase-out state based on the current current signal at the transformer neutral point and the preset phase-out current parameter, the controller will continue to obtain the current signal at the transformer neutral point in real time to monitor the duration of the transformer in the phase-out state. Only when it is determined that the duration of the transformer in the phase-out state is greater than or equal to the preset phase-out duration will the controller control the alarm device to output an alarm signal, thereby ensuring the accuracy of the transformer phase-out detection and avoiding unnecessary alarms triggered by transient interference or short-term transformer phase-out conditions. The preset phase-out duration can be determined according to actual needs, and the present invention does not specifically limit this.

[0109] Exemplarily, the alarm device may include an audible alarm device, such as a buzzer, which can emit a sound to promptly alert operators of the presence of a transformer in the transformer system in a phase-failure state. The alarm device may also include an optical alarm device, such as an LED light, which can flash the LED light to promptly alert operators of the presence of a transformer in the transformer system in a phase-failure state. The alarm device may also include a remote communication alarm device, such as a wireless module or Ethernet, which can transmit alarm information regarding the presence of a transformer in the transformer system in a phase-failure state to a control terminal of the nuclear power plant's transformer system, allowing operators to receive the alarm information via the control terminal. It is understood that the alarm information may also include the fault status of the transformer system determined based on at least one transformer in a phase-failure state. By using the alarm device to promptly alert operators to the transformer phase-failure fault, the operator can prevent further escalation of the fault within the transformer system, thereby improving the safety and maintenance efficiency of the nuclear power plant's transformer system and ensuring its reliable operation.

[0110] This embodiment determines the fault state of the transformer system based on at least one transformer in a phase-out state when at least one transformer among multiple transformers is in a phase-out state, thereby locating the fault state of the transformer system between the transformer and the circuit breaker connected thereto, between the circuit breaker and the busbar connected thereto, or between the busbar and the incoming line connected thereto, thereby achieving precise fault location, effectively improving the speed of fault troubleshooting, and enhancing maintenance efficiency. Furthermore, by controlling the alarm device to output an alarm signal when it is determined that the duration of the transformer phase-out state is greater than or equal to a preset phase-out duration, the accuracy of transformer phase-out detection is ensured, unnecessary alarms triggered by transient interference or short-term phase-out conditions are avoided, and the alarm device can be used to remind operators to promptly address the transformer phase-out fault, thereby preventing further expansion of the fault in the transformer system. This improves the safety and maintenance efficiency of the nuclear power plant's transformer system, ensuring the reliable operation of the nuclear power plant's transformer system.

[0111] Example 5

[0112] Figure 6 This is a schematic diagram of the structure of a transformer phase failure detection device for a transformer system according to the fifth embodiment of the present invention. The device can implement the transformer phase failure detection method for a transformer system according to the embodiment of the present invention. The device can be implemented by software and / or hardware and can generally be integrated into the controller of the transformer system. Figure 3 As shown, the device includes: a preset phase-break current parameter acquisition module 401, a neutral point current signal acquisition module 402 and a phase-break detection result determination module 403. The specific structure of the device is as follows:

[0113] The preset open-phase current parameter acquisition module 401 is used to obtain the preset open-phase current parameter of the transformer.

[0114] The neutral point current signal acquisition module 402 is used to acquire the current signal of the neutral point of each transformer in real time when a preset square wave signal is injected into the incoming line.

[0115] The phase failure detection result determination module 403 is configured to determine the current phase failure detection result of the transformer according to the current current signal of the neutral point of the transformer and the preset phase failure current parameter.

[0116] In an optional embodiment of the present invention, the preset phase-failure current parameter acquisition module 401 can also be used to: construct a transformer phase-failure circuit simulation model; inject a preset square wave signal into the transformer phase-failure circuit simulation model, and obtain a response current signal output by the transformer phase-failure circuit simulation model; determine the preset phase-failure current and the preset phase-failure duration based on the response current signal.

[0117] Among them, the transformer phase-failure circuit simulation model includes: a signal injection port, a first resistor, a second resistor, a first capacitor, a first inductor, a first switch and a current probe; the signal injection port is electrically connected between the first end of the first resistor and the second end of the first resistor; the second end of the first resistor and the first end of the first capacitor are respectively electrically connected to the first end of the second resistor; the first end of the first inductor is electrically connected to the second end of the second resistor; the second end of the first inductor and the second end of the first capacitor are both grounded; the current probe is arranged between the second end of the first capacitor and the second end of the first inductor; the first switch is arranged between the signal injection port and the first end of the first resistor; the difference between the resistance value of the first resistor and the line resistance value between the transformer and the corresponding incoming line part electrically connected to it is within a first preset range; the difference between the resistance value of the second resistor and the winding resistance value of the transformer is within the second preset range; the difference between the capacitance value of the first capacitor and the capacitance value of the transformer to ground is within a third preset range; the difference between the inductance value of the first inductor and the inductance value of the transformer is within a fourth preset range.

[0118] In an optional embodiment of the present invention, the preset phase-out current parameter acquisition module 401 can also be used to: when a preset square wave signal is injected into the signal injection port and the first switch is closed, obtain the first current signal between the second end of the first capacitor and the second end of the first inductor in real time based on the current probe, and determine the peak current in the first current signal as the first response current; when a preset square wave signal is injected into the signal injection port and the first switch is disconnected, obtain the second current signal between the second end of the first capacitor and the second end of the first inductor in real time based on the current probe, and determine the peak current in the second current signal as the second response current.

[0119] In an optional embodiment of the present invention, the preset open-phase current parameter acquisition module 401 may also be configured to: determine an average value of the first response current and the second response current as the preset open-phase current.

[0120] In an optional embodiment of the present invention, the preset phase-out current parameter acquisition module 401 can also be used to: determine the duration of the first current signal reaching a first preset percentage of the first response current as the first duration; and determine the preset phase-out duration based on the first duration.

[0121] In an optional embodiment of the present invention, the phase-failure detection result determination module 403 can also be used to: when there is a current signal less than or equal to a preset phase-failure current in the current signal of the neutral point of the transformer, obtain the duration of the current signal of the neutral point of the transformer being less than or equal to the preset phase-failure current; when the duration is greater than or equal to the preset phase-failure duration, determine that the transformer is currently in a phase-failure state.

[0122] In an optional embodiment of the present invention, the phase failure detection result determination module 403 may also be used to: when at least one transformer among multiple transformers is in a phase failure state, determine the fault state of the transformer system based on the at least one transformer in the phase failure state.

[0123] In an optional embodiment of the present invention, the phase-loss detection result determination module 403 can also be used to: when one of multiple transformers connected to the same circuit breaker is in a phase-loss state, determine that a fault exists between the transformer in the phase-loss state and the circuit breaker connected to it; when all transformers connected to the same circuit breaker are in a phase-loss state and any other transformers are in a non-phase-loss state, determine that a fault exists between the circuit breaker and the busbar connected to it; when the number of transformers connected to the same busbar in a phase-loss state reaches a preset number, determine that a fault exists between the busbar and the incoming line connected to it.

[0124] In an optional embodiment of the present invention, the phase failure detection result determination module 403 may also be configured to: when it is determined that the duration of the transformer being in the phase failure state is greater than or equal to a preset phase failure duration, control the alarm device to output an alarm signal.

[0125] The above-described transformer phase failure detection device for a transformer system can implement the transformer phase failure detection method for a transformer system provided by any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the method. For technical details not fully described in this embodiment, please refer to the transformer phase failure detection method for a transformer system provided by any embodiment of the present invention.

[0126] Since the transformer phase-break detection device for a transformer system described above is a device that can execute the transformer phase-break detection method for a transformer system in the embodiment of the present invention, based on the transformer phase-break detection method for a transformer system described in the embodiment of the present invention, those skilled in the art can understand the specific implementation and various variations of the transformer phase-break detection device for a transformer system in this embodiment. Therefore, how the transformer phase-break detection device for a transformer system implements the transformer phase-break detection method for a transformer system in the embodiment of the present invention will not be described in detail here. As long as those skilled in the art can implement the device used by the transformer phase-break detection method for a transformer system in the embodiment of the present invention, it falls within the scope of protection of this application.

[0127] Example 6

[0128] Figure 7 The following is a schematic diagram of a controller for a transformer system that can be used to implement embodiments of the present invention. The controller can take various forms to suit the operating environment and requirements of the transformer system, such as an industrial computer, an embedded controller, an intelligent monitoring terminal, and a transformer system control unit. These devices are specifically designed to monitor and adjust the operating parameters of the transformer system to ensure accurate and safe transformer phase failure detection in the transformer system. The components shown herein, their connections and relationships, and their functions are provided for illustrative purposes only and are not intended to limit the implementation of the present invention described and / or claimed herein.

[0129] like Figure 7 As shown, the controller 10 includes at least one processor 11 and memory, such as a read-only memory (ROM) 12 and a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer programs stored in the ROM 12 or loaded from the storage unit 18 into the RAM 13. The RAM 13 can also store various programs and data required for the operation of the controller 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0130] Multiple components in the controller 10 are connected to the I / O interface 15, including an input unit 16, such as an industrial keyboard or touch screen controller; an output unit 17, such as a display screen or an alarm indicator; a storage unit 18, such as an industrial hard drive or solid-state memory; and a communication unit 19, such as an industrial communication module or an Ethernet interface. The communication unit 19 allows the controller 10 to exchange information / data with other devices via, for example, an industrial control network and / or a nuclear power plant communication system.

[0131] The processor 11 can be any general-purpose and / or specialized processing component with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various specialized artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any other suitable processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as the transformer phase failure detection method for a transformer system.

[0132] In some embodiments, the transformer phase failure detection method for a transformer system can be implemented as a computer program tangibly embodied in a computer-readable storage medium, such as a memory unit. In some embodiments, part or all of the computer program can be loaded and / or installed onto the controller of the above-described embodiments via a ROM and / or a communication unit. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the transformer phase failure detection method for a transformer system described above can be performed. Alternatively, in other embodiments, processor 11 can be configured to execute the transformer phase failure detection method for a transformer system via any other suitable means (e.g., via firmware).

[0133] Optionally, a transformer phase loss detection method for a transformer system may include: obtaining a preset phase loss current parameter of the transformer; obtaining a current signal of the neutral point of each transformer in real time when injecting a preset square wave signal into the incoming line; and determining a current phase loss detection result of the transformer based on the current current signal of the neutral point of the transformer and the preset phase loss current parameter.

[0134] Various embodiments of the systems and techniques described above can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-chip systems (SOCs), programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include being implemented in one or more computer programs that are executable and / or interpreted on a programmable system that includes at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0135] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer program is executed by the processor, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The computer program may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0136] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, device, or apparatus. A computer-readable storage medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or apparatus, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media may include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0137] To provide user interaction, the systems and techniques described herein can be implemented on a controller that includes an industrial display device (e.g., an industrial LCD screen) for displaying information to the user, and an industrial keyboard and pointing device (e.g., a touch screen or keypad controller) through which the user can provide input to the controller. Other types of devices can also be used to provide user interaction; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback), and input from the user can be received in any form, including acoustic input, voice input, or tactile input.

[0138] The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0139] A computing system may include clients and servers. The clients and servers are typically remote from each other and typically interact via a communication network. This client-server relationship arises through computer programs running on the respective computers, creating a client-server relationship. The server may be a cloud server, also known as a cloud computing server or cloud host. This server is a hosting product within the cloud computing service ecosystem that addresses the management difficulties and limited scalability of traditional physical hosting and VPS services.

[0140] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present invention can be achieved. This is not limited herein.

[0141] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for detecting a phase failure of a transformer in a transformer system, characterized in that: The transformer system includes at least one incoming line unit and a plurality of transformers; Each of the transformers is electrically connected to the line input portion respectively; The transformer phase failure detection method of the transformer system comprises: Obtaining a preset open-phase current parameter of the transformer; When a preset square wave signal is injected into the incoming line, a current signal of the neutral point of each transformer is obtained in real time; The current open phase detection result of the transformer is determined according to the current current signal of the neutral point of the transformer and the preset open phase current parameter.

2. The transformer phase failure detection method of the transformer system according to claim 1, characterized in that: The preset phase-break current parameters include a preset phase-break current and a preset phase-break duration; Obtaining a preset open-phase current parameter of the transformer, including: Construct a transformer phase failure circuit simulation model; Injecting the preset square wave signal into the transformer open phase circuit simulation model, and obtaining a response current signal output by the transformer open phase circuit simulation model; The preset phase-off current and the preset phase-off duration are determined according to the response current signal.

3. The transformer phase failure detection method of the transformer system according to claim 2, characterized in that: The transformer phase failure circuit simulation model includes: a signal injection port, a first resistor, a second resistor, a first capacitor, a first inductor, a first switch and a current probe; The signal injection port is electrically connected between a first end of the first resistor and a second end of the first resistor; the second end of the first resistor and the first end of the first capacitor are electrically connected to the first end of the second resistor respectively; the first end of the first inductor is electrically connected to the second end of the second resistor; the second end of the first inductor and the second end of the first capacitor are both grounded; the current probe is arranged between the second end of the first capacitor and the second end of the first inductor; and the first switch is arranged between the signal injection port and the first end of the first resistor; The difference between the resistance value of the first resistor and the line resistance value between the transformer and the corresponding electrically connected incoming line part is within a first preset range; the difference between the resistance value of the second resistor and the winding resistance value of the transformer is within a second preset range; the difference between the capacitance value of the first capacitor and the ground capacitance value of the transformer is within a third preset range; and the difference between the inductance value of the first inductor and the inductance value of the transformer is within a fourth preset range.

4. The transformer phase failure detection method of the transformer system according to claim 3, characterized in that: Injecting the preset square wave signal into the transformer phase failure circuit simulation model and obtaining a response current signal output by the transformer phase failure circuit simulation model includes: When the preset square wave signal is injected into the signal injection port and the first switch is closed, obtaining a first current signal between the second end of the first capacitor and the second end of the first inductor in real time based on the current probe, and determining a peak current in the first current signal as a first response current; When the preset square wave signal is injected into the signal injection port and the first switch is disconnected, a second current signal between the second end of the first capacitor and the second end of the first inductor is acquired in real time based on the current probe, and a peak current in the second current signal is determined as a second response current.

5. The transformer phase failure detection method of the transformer system according to claim 4, characterized in that: Determining the preset open-phase current according to the response current signal includes: An average value of the first response current and the second response current is determined as the preset open-phase current.

6. The transformer phase failure detection method of the transformer system according to claim 4, characterized in that: Determining the preset phase-off duration according to the response current signal includes: determining a duration during which the first current signal reaches a first preset percentage of the first response current as a first duration; The preset phase-out duration is determined according to the first duration.

7. The transformer phase failure detection method of a transformer system according to claim 1, characterized in that: Determining a current phase failure detection result of the transformer according to a current current signal of the neutral point of the transformer and the preset phase failure current parameter includes: When a current signal less than or equal to a preset open-phase current exists in the current signal of the neutral point of the transformer, obtaining a duration during which the current signal of the neutral point of the transformer is less than or equal to the preset open-phase current; When the duration is greater than or equal to the preset phase-off duration, it is determined that the transformer is currently in a phase-off state.

8. The transformer phase failure detection method of a transformer system according to claim 1, characterized in that: The transformer system further includes at least one busbar and at least one circuit breaker; each transformer is electrically connected to the incoming line portion via the busbar; a first end of the circuit breaker is electrically connected to the busbar, and a second end of the circuit breaker is electrically connected to at least one transformer; the transformer phase failure detection method of the transformer system further includes: When at least one of the plurality of transformers is in a phase-off state, the fault state of the transformer system is determined based on the at least one transformer in the phase-off state.

9. The transformer phase failure detection method of the transformer system according to claim 8, characterized in that: When at least one of the plurality of transformers is in a phase-off state, determining a fault state of the transformer system according to the at least one transformer in the phase-off state includes: When one of the plurality of transformers connected to the same circuit breaker is in a phase-off state, determining that a fault exists between the transformer in the phase-off state and the circuit breaker connected thereto; When all the transformers connected to the same circuit breaker are in a phase-off state and any other transformers are in a non-phase-off state, determining that a fault exists between the circuit breaker and the busbar connected thereto; When the number of the transformers connected to the same busbar that are in a phase-out state reaches a preset number, it is determined that a fault exists between the busbar and the incoming line portion connected thereto.

10. The transformer phase failure detection method of a transformer system according to claim 1, characterized in that: The transformer system further includes an alarm device; and the transformer phase failure detection method of the transformer system further includes: When it is determined that the duration of the phase-off state of the transformer is greater than or equal to the preset phase-off duration, the alarm device is controlled to output an alarm signal.

11. A voltage transformation system, characterized in that: include: At least one incoming line unit, a plurality of transformers and a controller; Each of the transformers is electrically connected to the line input portion respectively; The controller is electrically connected to the incoming line and each of the transformers, and is used to execute the transformer phase failure detection method for the transformer system according to any one of claims 1 to 10.

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