Control method and device of transformer, computer device and storage medium

Abstract

The application relates to a transformer control method and device, computer equipment, a storage medium and a computer program product. The application is applied to a looped transformer connected with a first line and a second line, the looped transformer comprises a current conversion unit; the current conversion unit is used for outputting an adjusted voltage to a looped line; the method comprises the following steps: obtaining the number of turns of the looped transformer, a voltage difference and a phase difference between the first line and the second line; determining a compensation voltage of the looped line according to the voltage difference and the phase difference; determining an adjusted voltage of the current conversion unit according to the compensation voltage and the number of turns; and generating a driving control signal according to the adjusted voltage, wherein the driving control signal is used for controlling the current conversion unit to output the adjusted voltage. The method can realize dynamic matching of the voltages of the two lines in the looped process, reduce the looped impact current, and improve the safety and reliability of power distribution network transfer operation.

Description

Technical Field

[0001] This application relates to the field of power distribution technology, and in particular to a transformer control method, device, computer equipment, storage medium, and computer program product. Background Technology

[0002] With the expansion of power distribution networks and the increasing demands for power supply reliability, loop-connected operation has become an important operating mode. Loop-connected operation refers to the electrical connection of two power supply lines via tie switches or transformers to achieve load transfer, fault isolation, or uninterrupted maintenance. The loop-connecting transformer, as a key device connecting the two lines, directly affects the success of the operation and power quality. Currently, most of these transformers are mechanical on-load tap-changing or phase-shifting transformers used to regulate voltage amplitude and phase angle. The principle involves setting multiple taps on the windings, and changing the effective turns ratio by switching the tap positions with an on-load tap changer, thereby adjusting the output voltage to ensure that the voltage difference on both sides of the loop-connection point meets the parallel conditions. However, traditional tap adjustment methods have significant technical defects: the tap positions are discrete and stepped, and each adjustment can only be done in fixed step increments, failing to achieve continuous and smooth adjustment of amplitude and phase, thus affecting the stable operation of the system. Summary of the Invention

[0003] Therefore, it is necessary to provide a transformer control method, device, computer equipment, computer-readable storage medium, and computer program product to address the aforementioned technical problems.

[0004] In a first aspect, this application provides a control method for a transformer. Applied to a loop transformer connecting a first line and a second line, the loop transformer includes a converter unit; the converter unit is used to output a regulated voltage to the loop line, and the method includes:

[0005] Obtain the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line;

[0006] The compensation voltage of the closed loop circuit is determined based on the voltage difference and the phase difference; and the adjustment voltage of the converter unit is determined based on the compensation voltage and the number of turns.

[0007] Based on the regulated voltage, a drive control signal is generated, which is used to control the converter unit to output the regulated voltage.

[0008] In one embodiment, obtaining the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line includes:

[0009] Obtain the turns ratio of the closed-loop transformer; wherein the turns ratio is the ratio of the number of turns of the first winding to the number of turns of the second winding in the closed-loop transformer;

[0010] The voltage and current data of the first line and the voltage and current data of the second line are obtained, and the voltage amplitude difference and phase difference between the first line and the second line are determined based on the voltage and current data of the first line and the second line.

[0011] In one embodiment, determining the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference includes:

[0012] The amplitude compensation component is determined based on the voltage difference;

[0013] Based on the phase difference, determine the phase compensation component;

[0014] The compensation voltage is obtained by superimposing the amplitude compensation component and the phase compensation component.

[0015] In one embodiment, generating the drive control signal based on the adjusted voltage includes:

[0016] A modulation signal is generated based on the adjusted voltage;

[0017] The modulation signal is used as the drive control signal and output to the converter unit to control the on / off state of the converter unit's switching transistor, so that the converter unit outputs the regulated voltage.

[0018] In one embodiment, determining the regulating voltage of the converter unit based on the compensation voltage and the number of turns includes:

[0019] Obtain the turns ratio of the series compensation winding to the main winding in the closed-loop transformer;

[0020] The initial voltage of the converter unit is determined based on the compensation voltage and the turns ratio.

[0021] If the initial voltage exceeds a preset adjustment threshold, the preset adjustment threshold is determined as the adjustment voltage;

[0022] If the initial voltage does not exceed the preset adjustment threshold, the initial voltage is determined as the adjustment voltage.

[0023] In one embodiment, the method further includes:

[0024] When the converter unit is operating, the operating voltage difference and operating phase difference between the first line and the second line are obtained;

[0025] The regulating voltage is determined and adjusted based on the operating voltage difference and the operating phase difference.

[0026] Secondly, this application also provides a control device for a transformer. Applied to a loop transformer connecting a first line and a second line, the loop transformer includes a converter unit; the converter unit is used to output a regulated voltage to the loop line, and the device includes:

[0027] The data acquisition module is used to acquire the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line;

[0028] A voltage determination module is used to determine the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference; and to determine the adjustment voltage of the converter unit based on the compensation voltage and the number of turns.

[0029] A voltage output module is used to generate a drive control signal based on the regulated voltage, and the drive control signal is used to control the converter unit to output the regulated voltage.

[0030] In one embodiment, the closed-loop transformer further includes a series compensation winding; the series compensation winding and the main winding of the closed-loop transformer are wound on the same core column; and the series compensation winding and the main winding are spaced apart from each other in the axial direction of the core column.

[0031] In one embodiment, the data acquisition module is further configured to:

[0032] Obtain the turns ratio of the closed-loop transformer; wherein the turns ratio is the ratio of the number of turns of the first winding to the number of turns of the second winding in the closed-loop transformer;

[0033] The voltage and current data of the first line and the voltage and current data of the second line are obtained, and the voltage amplitude difference and phase difference between the first line and the second line are determined based on the voltage and current data of the first line and the second line.

[0034] In one embodiment, the voltage determination module is further configured to:

[0035] The amplitude compensation component is determined based on the voltage difference;

[0036] Based on the phase difference, determine the phase compensation component;

[0037] The compensation voltage is obtained by superimposing the amplitude compensation component and the phase compensation component.

[0038] In one embodiment, the voltage output module is further configured to:

[0039] A modulation signal is generated based on the adjusted voltage;

[0040] The modulation signal is used as the drive control signal and output to the converter unit to control the on / off state of the converter unit's switching transistor, so that the converter unit outputs the regulated voltage.

[0041] In one embodiment, the voltage determination module is further configured to,

[0042] Obtain the turns ratio of the series compensation winding to the main winding in the closed-loop transformer;

[0043] The initial voltage of the converter unit is determined based on the compensation voltage and the turns ratio.

[0044] If the initial voltage exceeds a preset adjustment threshold, the preset adjustment threshold is determined as the adjustment voltage;

[0045] If the initial voltage does not exceed the preset adjustment threshold, the initial voltage is determined as the adjustment voltage.

[0046] In one embodiment, the voltage determination module is further configured to:

[0047] When the converter unit is operating, the operating voltage difference and operating phase difference between the first line and the second line are obtained;

[0048] The regulating voltage is determined and adjusted based on the operating voltage difference and the operating phase difference.

[0049] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the transformer control method as described in any one of the embodiments of this disclosure.

[0050] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, implements the transformer control method as described in any one of the embodiments of this disclosure.

[0051] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the transformer control method as described in any one of the embodiments of this disclosure.

[0052] The aforementioned control methods, devices, computer equipment, storage media, and computer program products for transformers organically integrate electromagnetic transformers with power electronic converter units. Through continuous voltage injection via series compensation windings, they eliminate the reliance on mechanical tap switching found in traditional transformers. This not only removes the complex winding lead-out and tap-switching processes in tap manufacturing but also fundamentally overcomes the inherent defects of mechanical voltage regulating devices, such as discrete tap positions and slow response. Based on this structure, zero-difference matching of line voltage amplitude and phase is achieved on both sides of the loop closing point, thereby maximizing the suppression of inrush circulating currents. Simultaneously, by utilizing real-time synchronous sampling and dynamic compensation demand calculation, combined with a closed-loop adaptive adjustment strategy, this method can continuously optimize the injected voltage according to the grid operating conditions, accurately adapting to real-time voltage differences. In scenarios where distribution network loads fluctuate frequently or where large-scale distributed power source integration leads to rapid voltage changes, this technology significantly improves the success rate of loop closing operations and power supply continuity, providing solid technical support for the flexible and efficient operation of highly reliable distribution networks. Attached Figure Description

[0053] Figure 1 This is a flowchart illustrating a transformer control method in one embodiment;

[0054] Figure 2 This is a topology diagram of the device implementing the transformer control method in one embodiment;

[0055] Figure 3 A system architecture diagram illustrating the implementation of a transformer control method in one embodiment;

[0056] Figure 4 This is a flowchart illustrating the implementation of a transformer control method in one embodiment;

[0057] Figure 5 This is a structural block diagram of the control device for a transformer in one embodiment;

[0058] Figure 6 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0060] In one embodiment, such as Figure 1 As shown, a control method for a transformer is provided, applied to a loop transformer connecting a first line and a second line. The loop transformer includes a converter unit; the converter unit is used to output a regulated voltage to the loop line. The method includes:

[0061] Step S100: Obtain the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line.

[0062] The number of turns of the closed-loop transformer may include the number of turns of the main winding and the series compensation winding, which can be obtained through equipment nameplate parameters or pre-stored configuration data; the voltage difference and phase difference between the first line and the second line can be obtained by synchronously sampling the voltage signals of the two lines and calculating them based on methods such as phase-locked loop (PLL) or Fourier transform.

[0063] In one exemplary embodiment, the voltage difference and phase difference can be acquired based on a high-precision synchronous phasor measurement unit (PMU) to ensure that the electrical quantities of the two lines are compared under a unified time reference, thereby improving compensation accuracy. An amplitude compensation component can also be calculated based on the acquired voltage difference, which can be used to offset the deviation of the effective voltage values ​​between the first and second lines. A phase compensation component can be determined based on the phase difference to correct the inconsistency of the phase angles of the two lines. The two components are then vector-synthesized in the complex domain to obtain the compensation voltage command required for the closed-loop circuit.

[0064] In one exemplary embodiment, the compensation voltage can be converted into the initial voltage that the converter unit should output, based on the turns ratio of the series compensation winding to the main winding in the closed-loop transformer. A preset adjustment threshold can also be set. When the initial voltage exceeds this threshold, it can be clamped at the threshold boundary to avoid over-adjustment causing equipment overload or insulation breakdown; if it does not exceed the limit, the initial voltage is directly used as the final adjustment voltage. After the converter unit is put into operation, the actual operating voltage difference and operating phase difference between the first and second lines can be continuously monitored, and the adjustment voltage can be dynamically corrected based on real-time data, forming a closed-loop feedback control.

[0065] Step S102: Determine the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference; and determine the adjustment voltage of the converter unit based on the compensation voltage and the number of turns.

[0066] The number of turns here represents the turns ratio between the series compensation winding and the main winding in the closed-loop transformer. This turns ratio determines the electromagnetic coupling relationship between the output voltage of the converter unit and the required compensation voltage of the closed-loop circuit. Based on this turns ratio, the calculated compensation voltage can be proportionally converted into the actual regulating voltage that the converter unit needs to provide. The regulating voltage represents the voltage amplitude and phase command that the converter unit needs to output, injecting an appropriate compensation potential at the closed-loop point to offset the voltage imbalance between the two lines.

[0067] In one exemplary embodiment, determining the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference may specifically include using a first line voltage phasor and a second line voltage phasor obtained by synchronous sampling, using the first line voltage phasor as a reference, calculating the vector difference between the two phasors in a polar coordinate system or a synchronous rotating coordinate system, and determining the vector difference as the theoretical compensation voltage phasor required for the closed loop circuit.

[0068] In one exemplary embodiment, the theoretical compensation voltage phasor can be decomposed into active and reactive components. Based on the turns ratio between the series compensation winding and the main winding of the closed-loop transformer, the two components are proportionally converted to obtain the initial voltage command phasor on the output side of the converter unit. Specifically, the amplitude and phase of the initial voltage command phasor can be further mapped to the modulation wave parameters required by the pulse width modulation controller. If the amplitude of the initial voltage command phasor exceeds the rated output capacity of the converter unit or a preset safety adjustment threshold, its amplitude can be limited while maintaining the phase to ensure safe operation of the equipment. If it does not exceed the limit, the phasor can be directly used as the final adjustment voltage command. A corresponding drive control signal can also be generated based on the adjustment voltage command to control the on / off timing of the power switching devices in the converter unit, enabling the converter unit to inject an adjustment voltage matching the theoretical compensation voltage into the closed-loop circuit in real time. This effectively reduces the voltage difference and phase difference on both sides of the closed-loop point, achieving a smooth, shock-free closed-loop operation.

[0069] Step S104: Generate a drive control signal based on the regulated voltage. The drive control signal is used to control the converter unit to output the regulated voltage.

[0070] In one exemplary embodiment, the generation of the drive control signal can employ sinusoidal pulse width modulation (PWM) or space vector pulse width modulation (SVM) strategies to convert the amplitude and phase information of the regulated voltage into a PWM waveform with corresponding duty cycle and switching timing. The PWM waveform, after being amplified by the drive circuit, is used to control the on / off switching of power switching devices such as IGBTs (Insulated Gate Bipolar Transistors) or MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) in the converter unit, thereby synthesizing the required frequency, amplitude, and phase regulated voltage on the series compensation winding side. Because the converter unit achieves continuous and controllable output through power electronic conversion, compared to traditional mechanical on-load tap changers, it can dynamically compensate for the closing-loop voltage difference with a millisecond-level response speed, effectively eliminating the regulation blind zone caused by discrete tap switching, and significantly improving the smoothness of the closing-loop operation and the stability of the system operation. In addition, the drive control signal can also be embedded with dead-time compensation, overcurrent protection and fault blocking logic to ensure rapid output cut-off under abnormal operating conditions and protect the safety of equipment and power grid.

[0071] The aforementioned transformer control method organically integrates an electromagnetic transformer with a power electronic converter unit. Through continuous voltage injection via series compensation windings, it eliminates the reliance on mechanical tap switching found in traditional transformers. This not only removes the complex winding lead-out and tap-switching processes in tap manufacturing but also fundamentally overcomes the inherent defects of mechanical voltage regulators, such as discrete tap positions and sluggish response. Based on this structure, zero-difference matching of voltage amplitude and phase is achieved on both sides of the loop closing point, thereby maximizing the suppression of inrush circulating currents. Simultaneously, by utilizing real-time synchronous sampling and dynamic compensation demand calculation, combined with a closed-loop adaptive adjustment strategy, this method can continuously optimize the injected voltage according to the grid operating conditions, accurately adapting to real-time voltage differences. In scenarios where distribution network load fluctuates frequently or a large number of distributed power sources are connected, leading to rapid voltage changes, this technology significantly improves the success rate of loop closing operations and power supply continuity, providing solid technical support for the flexible and efficient operation of highly reliable distribution networks.

[0072] In one embodiment, obtaining the number of turns of the closed-loop transformer, the voltage difference between the first line and the second line, and the phase difference includes:

[0073] Obtain the turns ratio of the closed-loop transformer; wherein the turns ratio is the ratio of the number of turns of the first winding to the number of turns of the second winding in the closed-loop transformer.

[0074] The voltage and current data of the first line and the voltage and current data of the second line are obtained, and the voltage amplitude difference and phase difference between the first line and the second line are determined based on the voltage and current data of the first line and the second line.

[0075] The voltage and current data can be synchronously acquired by high-precision sensors deployed on the first and second lines and uploaded to the control device in real time via a communication unit. The voltage amplitude difference can be obtained by calculating the difference between the effective values ​​of the voltages on both sides, and the phase difference can be determined based on the time offset of the zero-crossing points of the two voltage signals at the synchronous sampling time or by the phase angle information extracted by the phase-locked loop. In the presence of harmonic interference, fast Fourier transform or wavelet analysis can be used to extract the fundamental component to ensure that the obtained voltage and phase differences reflect the steady-state operating characteristics of the system and avoid distortion of compensation commands due to high-frequency noise. In addition, the sampling results of multiple consecutive cycles can be processed by moving average or Kalman filtering to suppress the influence of instantaneous disturbances on the compensation decision.

[0076] In one exemplary embodiment, the turns ratio can be obtained directly by reading the nameplate parameters of the closed-loop transformer or the equipment factory configuration file; if the transformer has undergone winding modification or tap adjustment after commissioning, it can be measured on-site by a turns ratio tester and updated and stored in the local controller or remote dispatch master station to ensure that the turns ratio parameter is consistent with the actual physical structure in real time.

[0077] In one exemplary embodiment, the voltage and current data of the first line and the second line can be synchronously acquired by electronic voltage transformers and electronic current transformers installed at the outlets of the two lines respectively, and the pulse-per-second (PPS) signal provided by the Global Positioning System (GPS) or the Beidou Satellite Navigation System is used as a unified synchronization clock to ensure that the phase reference of the sampled data on both sides is consistent, thereby eliminating the impact of synchronization error caused by sampling in different locations on the accuracy of phase difference calculation.

[0078] In this embodiment, the accuracy and timeliness of key input quantities such as voltage difference, phase difference and turns ratio are ensured by a high-precision synchronous sampling and real-time parameter update mechanism, laying the foundation for the accurate calculation of subsequent compensation voltage.

[0079] In one embodiment, determining the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference includes:

[0080] The amplitude compensation component is determined based on the voltage difference.

[0081] Based on the phase difference, the phase compensation component is determined.

[0082] The compensation voltage is obtained by superimposing the amplitude compensation component and the phase compensation component.

[0083] The voltage difference can characterize the difference between the effective voltage values ​​of the first line and the second line under the same time reference, and can include a signed scalar calculated by subtracting the effective voltage value of the second line from the effective voltage value of the first line. The phase difference can characterize the angular difference between the fundamental phase angles of the first line voltage and the second line voltage, and can include a signed angle calculated using the fundamental phase angle of the first line voltage as a reference. The amplitude compensation component can characterize the voltage adjustment amount used to offset the voltage difference, its amplitude being equal to the difference between the effective voltage values ​​on both sides, and its direction being opposite to the polarity of the voltage difference. The phase of this component can be either in the same direction or opposite to the first line voltage phasor. The phase compensation component can characterize the voltage adjustment amount used to correct the phase difference, its direction being orthogonal to the current voltage phasor direction, and can include a q-axis (cross-axis) voltage component in a synchronously rotating coordinate system, the amplitude of which can be determined by the product of the sine function value of the phase difference and the system voltage amplitude. The compensation voltage can characterize the voltage phasor obtained by superimposing the amplitude compensation component and the phase compensation component in the vector domain, which is the theoretical target voltage value to be injected into the loop circuit. It can include a composite voltage command that simultaneously covers amplitude correction information and phase correction information.

[0084] In one exemplary embodiment, determining the amplitude compensation component based on the voltage difference can be achieved using a proportional adjustment method. Specifically, this can include multiplying the acquired voltage difference by a preset proportional coefficient to directly obtain the amplitude of the amplitude compensation component, with its phase aligned with the phasor of the first line voltage. Alternatively, an integral term can be introduced based on the proportional adjustment to correct for the accumulated error of the voltage difference, forming a regulator to eliminate steady-state amplitude deviation caused by transformer ratio errors or measurement noise.

[0085] In one exemplary embodiment, determining the phase compensation component based on the phase difference can be achieved by substituting the phase difference into a sine function and multiplying it by the current amplitude of the first line voltage to obtain the amplitude of the phase compensation component. The direction of the phase compensation component is set to be orthogonal to the first line voltage phasor. Specifically, this can include taking an orthogonal leading direction when the phase of the second line voltage lags behind the first line voltage to push the phase angle of the closing point voltage forward; and taking a lag orthogonal direction when the phase of the second line voltage leads the first line voltage to pull the phase angle of the closing point voltage backward.

[0086] In one exemplary embodiment, the superposition of the amplitude compensation component and the phase compensation component to obtain the compensation voltage can be completed in a synchronous rotating coordinate system. Specifically, it can include mapping the amplitude compensation component to the d-axis (direct axis) and the phase compensation component to the q-axis (intersecting axis), performing vector addition between the two in the dq coordinate system to obtain a composite vector, and converting it back to the stationary three-phase coordinate system through an inverse Park transformation to obtain the instantaneous value expression of the compensation voltage.

[0087] In this embodiment, by decomposing the compensation voltage into amplitude compensation components and phase compensation components, calculating them separately, and then superimposing them, decoupled adjustment of amplitude and phase is achieved. The two components can be set with limiting and adjustment parameters independently, reducing the complexity of controller design; moreover, the two are not coupled, and the adjustment of one component will not interfere with the other component, improving the stability and adjustment accuracy of the compensation system.

[0088] In one embodiment, generating the drive control signal based on the adjusted voltage includes:

[0089] A modulation signal is generated based on the adjusted voltage.

[0090] The modulation signal is used as the drive control signal and output to the converter unit to control the on / off state of the converter unit's switching transistor, so that the converter unit outputs the regulated voltage.

[0091] The modulation signal can characterize the pulse command used to control the power switching devices in the converter unit to turn on and off, and can include PWM pulse sequence or SPWM / SVPWM modulation waveform. The duty cycle and timing can be used to determine the amplitude and phase of the output voltage of the converter unit.

[0092] In one exemplary embodiment, the generation of the modulation signal based on the regulated voltage can be implemented using a sinusoidal pulse width modulation (SPWM) strategy. Specifically, this can include comparing the amplitude information of the regulated voltage with a preset triangular carrier wave to generate a PWM pulse sequence whose duty cycle changes with the instantaneous value of the regulated voltage. Simultaneously, the phase information of the regulated voltage is correlated with the three-phase modulation wave through a synchronization signal, ensuring that the generated PWM pulses maintain a phase difference threshold between the three phases. This allows for the synthesis of a three-phase AC voltage at the output side of the converter unit whose amplitude and phase both conform to the regulated voltage command. Alternatively, the generation of the modulation signal based on the regulated voltage can be implemented using a space vector pulse width modulation (SPWM) strategy. Specifically, this can include converting the regulated voltage to a stationary two-phase coordinate system, determining the sector position and duration of the target voltage vector based on its amplitude and phase, generating the switching sequence of the corresponding power switching devices, so that the voltage vector output by the converter unit approximates a circular trajectory during rotation. Compared to SPWM, this improves the DC bus voltage utilization and reduces the output harmonic content. After generating the modulation signal, dead-time compensation processing can be performed on the modulation signal: based on the on-state voltage drop and turn-off delay characteristics of the converter unit switching transistor, a preset dead time is inserted at the switching moment of the upper and lower bridge arm switches, and the voltage distortion caused by the dead-time insertion is corrected by the feedforward compensation amount to eliminate the amplitude loss and phase deviation introduced by the dead-time effect.

[0093] In this embodiment, by generating a modulation signal based on the regulated voltage and directly outputting this modulation signal as a drive control signal to the converter unit, a rapid conversion from the regulated voltage command to the power device on / off control quantity is achieved. This scheme avoids complex intermediate conversion steps, resulting in a simple and efficient signal chain, which helps reduce control delay and improve the converter unit's output voltage's response speed to commands.

[0094] In one embodiment, determining the regulating voltage of the converter unit based on the compensation voltage and the number of turns includes:

[0095] Obtain the turns ratio of the series compensation winding to the main winding in the closed-loop transformer.

[0096] The initial voltage of the converter unit is determined based on the compensation voltage and the turns ratio.

[0097] If the initial voltage exceeds a preset adjustment threshold, the preset adjustment threshold is determined as the adjustment voltage.

[0098] If the initial voltage does not exceed the preset adjustment threshold, the initial voltage is determined as the adjustment voltage.

[0099] The turns ratio represents the ratio of the number of turns in the series compensation winding to the number of turns in the closed-loop transformer. It can include ratios obtained from equipment nameplate parameters, factory configuration files, or on-site measurements, and is used to convert the compensation voltage on the closed-loop line side to the electrical quantity on the converter unit output side. The initial voltage represents the voltage command that the converter unit should output, calculated based on the compensation voltage and the turns ratio. It can include the original calculated value before amplitude limiting, and its amplitude may exceed the safe operating range of the equipment due to extreme system conditions or measurement anomalies. The preset adjustment threshold represents the maximum allowable value of the converter unit output voltage, which can include a limiting boundary determined comprehensively based on the withstand voltage rating of the power switching devices in the converter unit, the DC bus voltage utilization rate, and insulation coordination requirements.

[0100] In one exemplary embodiment, the turns ratio can be directly obtained by reading the nameplate parameters or factory configuration file of the closed-loop transformer. If the transformer has undergone winding modifications or tap adjustments after commissioning, the turns ratio can be measured on-site using a turns ratio tester and updated and stored in the controller to ensure that the turns ratio parameters are consistent with the actual physical structure. The preset adjustment threshold can be determined based on the voltage withstand capability of the power switching devices in the converter unit, and can be set to ±X% of the rated output voltage. When the amplitude of the initial voltage exceeds the threshold, the threshold is used as the adjustment voltage output to avoid over-modulation operation of the converter unit, which could lead to overvoltage breakdown or insulation damage of the switching devices. After the preset adjustment threshold is determined as the adjustment voltage, an alarm signal can also be generated to indicate that the current required compensation amount exceeds the adjustment capability range of the converter unit. The closed-loop operation can continue, but the level of the closed-loop inrush current needs to be monitored. At the same time, the difference between the current actual compensation amount and the required compensation amount can be displayed on the human-machine interface or the scheduling background for maintenance personnel to assess the risk level of this closed-loop operation.

[0101] In this embodiment, by setting a preset adjustment threshold, the threshold is automatically determined as the adjustment voltage when the initial voltage exceeds the limit, which can effectively prevent the converter unit from outputting an excessively high adjustment voltage.

[0102] In one embodiment, the method further includes:

[0103] When the converter unit is in operation, the operating voltage difference and operating phase difference between the first line and the second line are obtained.

[0104] The regulating voltage is determined and adjusted based on the operating voltage difference and the operating phase difference.

[0105] The operating voltage difference can represent the difference between the current effective voltage values ​​of the first line and the second line, acquired in real time when the converter unit is in operation. It can include real-time values ​​with the same definition as the aforementioned voltage difference but dynamically updated over time. The operating phase difference can represent the difference between the current fundamental phase angle of the voltage between the first line and the second line, acquired in real time when the converter unit is in operation. It can include real-time values ​​with the same definition as the aforementioned phase difference but dynamically updated over time.

[0106] In one exemplary embodiment, the acquisition of the operating voltage difference and operating phase difference between the first and second lines can employ the same synchronous sampling method as the initial acquisition of the voltage and phase differences, repeated at a fixed period to acquire real-time voltage data of both lines. The current effective voltage value and fundamental phase angle are then extracted using a phase-locked loop or Fourier transform to calculate the operating voltage difference and operating phase difference. The determination and adjustment of the regulating voltage based on the operating voltage difference and operating phase difference can be achieved by using the acquired operating voltage difference and operating phase difference as new input quantities. The regulating voltage is recalculated following the same steps as determining the compensation voltage and regulating voltage, and the updated regulating voltage replaces the original regulating voltage, allowing the converter unit's output to dynamically track and adjust according to changes in the real-time state of the power grid. The period for determining and adjusting the regulating voltage can adaptively vary according to the degree of power grid fluctuation: when the rate of change of the operating voltage difference or operating phase difference exceeds a preset threshold, the adjustment period is shortened to improve response speed; when the power grid is operating smoothly and the error change is small, the adjustment period is extended to reduce the controller's computational burden and switching losses.

[0107] In this embodiment, a closed-loop feedback control mechanism is formed by continuously acquiring the operating voltage difference and operating phase difference of the two lines during the operation of the converter unit, and dynamically adjusting the regulating voltage based on real-time data. This scheme can automatically track changes in the grid operating status. When the voltage of the two lines changes due to load fluctuations, changes in distributed power generation output, or system topology adjustments, the regulating voltage output by the converter unit is updated accordingly, ensuring that the voltage on both sides of the loop closure point is always maintained within the allowable deviation range.

[0108] In one exemplary embodiment, a topology diagram of a transformer control method implementation device is provided, specifically as follows: Figure 2As shown, the transformer is based on a five-column structure. The leftmost and rightmost columns are side windings without windings, while the middle three columns have three-phase windings. Furthermore, the core of each phase can be split into columns 1 and 2 to achieve core integration. Taking phase A as an example, winding U1A of line 1 is wound forward on both columns 1 and 2, and winding U2A of line 2 is wound forward on both columns 1 and 2. Simultaneously, winding U2A is connected in series with the series winding Usa used for regulation; Usa is wound forward on column 1 and reverse on column 2. Uea is the energy extraction winding of the back-to-back power electronics section, wound forward on both columns 1 and 2. Uia is the output winding of the back-to-back power electronics section, wound forward on column 1 and reverse on column 2. Windings U1A and U2A have the same number of turns. The key to the integration and decoupling lies in the winding direction of the different windings on posts 1 and 2. Based on whether the windings are all wound in the forward direction on both posts 1 and 2, or wound in opposite directions on posts 1 and 2, the coils can be divided into two groups. Windings with the same winding rules are coupled together, while windings with different rules are decoupled. The principle is that all windings on post 1 are wound in the forward direction, thus inducing a positive voltage in that section. Windings wound in the forward direction on post 2 induce a positive voltage, while those wound in the reverse direction on post 2 induce a negative voltage. Therefore, for windings wound in opposite directions on posts 1 and 2, the induced voltages are also opposite, canceling each other out. To an external observer, no induced voltage is generated in the entire winding, thus exhibiting decoupling. The terms "forward winding" and "reverse winding" describe different winding directions of the windings. These can be determined using Ampere's right-hand rule: the same direction indicates the same winding direction, and opposite directions indicate reverse winding direction. The three-phase windings of line 1 and line 2 (the entire windings connected in series with the series windings) can be connected in a delta configuration, with the connection points of the external busbars being the three vertices of the triangle. For the back-to-back power electronics section, the three-phase power supply winding (Ue) is connected in a delta configuration, and the output winding (Ui) is connected in a star configuration. The back-to-back power electronics section employs a three-level neutral point clamping structure, with the neutral point ungrounded; ensuring that the three magnetic fluxes do not affect the external environment.

[0109] In one exemplary embodiment, a system structure diagram for implementing a transformer control method is provided, specifically as follows: Figure 3As shown, a 10kV / 10kV dual-power system is used as an example. The flexible loop transformer connects two 10kV lines. Tie switches K1 and K2 are installed on both sides of line 1 and line 2 respectively, and a bypass switch K3 is connected in parallel with the flexible loop transformer. Voltage and current transformers on both sides of the tie lines measure the state of line 1 and line 2 for back-to-back output calculations. Taking an adjustment range of ±10% as an example, the flexible loop transformer needs to balance a 10% voltage difference. The phase voltage of 10kV is approximately 5.77kV, and the maximum amplitude of the 10% injection voltage is approximately 580V. Two design schemes are provided: a back-to-back AC side design of 690V and a DC bus voltage of approximately 1100V. In this case, the turns ratio of the line windings (U1, U2) to the power supply winding (Ue) is approximately 5770:690. The turns ratio of the output winding (Ui) to the series winding (Us) is 1:1. In this design, the maximum steady-state voltage that the switching transistor withstands when turned off does not exceed 600V, so a 1200V Si IGBT (Silicon Insulated Gate Bipolar Transistor) can be selected. The back-to-back AC side is designed at 1140V, and the DC bus is approximately 1800V. At this time, the turns ratio of the line windings (U1, U2) to the power supply winding (Ue) is approximately 5770:1140. The turns ratio of the output winding (Ui) to the series winding (Us) is 2:1. In this design, the maximum steady-state voltage that the switching transistor withstands when turned off does not exceed 900V, so a 1700V Si IGBT can be selected. When a loop-closing operation is required, the dispatcher first issues a command, and then the flexible loop-closing transformer will provide feedback on its self-test status, checking that all equipment, including the back-to-back converter, is operating normally. Then, the tie switch K1 closes, charging the back-to-back DC buses. Simultaneously, the system acquires the voltage and current signals from both sides and calculates the amplitude and phase difference of the voltages on both sides, which is the adjustment voltage required for the output winding. The turns ratio and phase difference due to differences in device configuration are also taken into account (e.g., the aforementioned 2:1 turns ratio; the fixed 30-degree phase angle difference caused by the delta connection of the output winding and the star connection of the series winding). The drive switch then inverts the required voltage signal, coupling it into line 2 via the series winding. Throughout the process, the voltage and current signals of line 1 and line 2 are continuously monitored to maintain the voltage difference within the allowed range. Once within the allowable range, the tie switch K2 closes, and after the lines on both sides stabilize, the bypass switch K3 closes, deactivating the flexible closed-loop transformer. For auxiliary equipment in the flexible closed-loop transformer device that requires long-term online operation (e.g., command reception, self-test program, status transmission, etc.), energy harvesting transformers are also equipped on both line 1 and line 2 sides for power supply.

[0110] In one exemplary embodiment, the transformer control method can be as follows: Figure 4 The implementation shown may specifically include:

[0111] Step S400, Receive transfer instruction: The system receives the loop transfer instruction issued by the dispatcher and starts the loop operation process.

[0112] Step S402, Flexible loop transformer status self-check; The flexible loop transformer performs a system self-check on the entire device, focusing on the working status of back-to-back converters, winding connections, switch status, and communication links.

[0113] Step S404: Determine if the self-test is normal; if yes, proceed to step S408; if no, proceed to step S406.

[0114] Step S406, Alarm: Enter alarm state and wait for manual intervention or fault recovery.

[0115] Step S408: Close tie switch K1 to charge the DC bus; after confirming the system is normal, first close tie switch K1 closest to line 1, connecting the flexible closed-loop transformer to line 1 to prepare for subsequent voltage detection and regulation. The DC bus of the back-to-back power electronics section begins pre-charging to establish a stable DC voltage, providing the energy basis for adjusting the output voltage on the inverter side.

[0116] Step S410: Read the current and voltage signals of line 1 and line 2; use voltage and current transformers arranged on both sides of the tie line to collect the voltage amplitude, phase and current information of line 1 and line 2 in real time to calculate the difference between them.

[0117] Step S412: Calculate the amplitude and phase of the inverter-side output voltage. Based on the measured voltage signals of line 1 and line 2, combined with parameters such as the inherent turns ratio of the device and the winding connection method (such as the fixed phase offset introduced by delta / star connection), calculate the adjustment voltage amplitude and phase to be injected into the series winding so that the voltage on line 2 is consistent with that on line 1.

[0118] Step S414: Drive the switching transistor to start outputting the adjustment voltage; based on the calculation results, drive the switching transistor (such as Si IGBT) in the back-to-back converter to invert the required adjustment voltage, and couple it into the line 2 side through the series winding (Us) to start actively adjusting the voltage amplitude and phase of the line 2 side.

[0119] Step S416: Compare the current and voltage signals of line 1 and line 2 to determine the amplitude and phase angle difference; continuously monitor the real-time voltage and current signals of line 1 and line 2, and calculate the amplitude difference and phase angle difference on both sides.

[0120] Step S518: Determine whether the difference is within the allowable range. If not, return to step S410; if yes, proceed to step S420.

[0121] Step S420: Close the tie switch K2 to perform loop closing; when the voltage amplitude and phase difference between line 1 and line 2 meet the safety loop closing conditions, close the tie switch K2 closest to line 2 to complete the loop connection of the two lines.

[0122] Step S422: After stabilization, close the bypass switch K3 to disconnect the flexible loop transformer; after looping, maintain short-term stable operation. After confirming that the ring network is operating normally, close the bypass switch K3 to disconnect the flexible loop transformer from the line, and the device will be taken out of operation, completing all uninterrupted power supply operations.

[0123] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0124] Based on the same inventive concept, this application also provides a transformer control device for implementing the transformer control method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more transformer control device embodiments provided below can be found in the limitations of the transformer control method described above, and will not be repeated here.

[0125] In one embodiment, such as Figure 5 As shown, a control device 500 for a transformer is provided, applied to a loop transformer connecting a first line and a second line. The loop transformer includes a converter unit; the converter unit is used to output a regulated voltage to the loop line. The device includes: a data acquisition module 501, a voltage determination module 503, and a voltage output module 505, wherein:

[0126] The data acquisition module is used to acquire the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line;

[0127] A voltage determination module is used to determine the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference; and to determine the adjustment voltage of the converter unit based on the compensation voltage and the number of turns.

[0128] A voltage output module is used to generate a drive control signal based on the regulated voltage, and the drive control signal is used to control the converter unit to output the regulated voltage.

[0129] In one embodiment, the closed-loop transformer further includes a series compensation winding; the series compensation winding and the main winding of the closed-loop transformer are wound on the same core column; and the series compensation winding and the main winding are spaced apart from each other in the axial direction of the core column.

[0130] In one embodiment, the data acquisition module is further configured to:

[0131] Obtain the turns ratio of the closed-loop transformer; wherein the turns ratio is the ratio of the number of turns of the first winding to the number of turns of the second winding in the closed-loop transformer;

[0132] The voltage and current data of the first line and the voltage and current data of the second line are obtained, and the voltage amplitude difference and phase difference between the first line and the second line are determined based on the voltage and current data of the first line and the second line.

[0133] In one embodiment, the voltage determination module is further configured to:

[0134] The amplitude compensation component is determined based on the voltage difference;

[0135] Based on the phase difference, determine the phase compensation component;

[0136] The compensation voltage is obtained by superimposing the amplitude compensation component and the phase compensation component.

[0137] In one embodiment, the voltage output module is further configured to:

[0138] A modulation signal is generated based on the adjusted voltage;

[0139] The modulation signal is used as the drive control signal and output to the converter unit to control the on / off state of the converter unit's switching transistor, so that the converter unit outputs the regulated voltage.

[0140] In one embodiment, the voltage determination module is further configured to,

[0141] Obtain the turns ratio of the series compensation winding to the main winding in the closed-loop transformer;

[0142] The initial voltage of the converter unit is determined based on the compensation voltage and the turns ratio.

[0143] If the initial voltage exceeds a preset adjustment threshold, the preset adjustment threshold is determined as the adjustment voltage;

[0144] If the initial voltage does not exceed the preset adjustment threshold, the initial voltage is determined as the adjustment voltage.

[0145] In one embodiment, the voltage determination module is further configured to:

[0146] When the converter unit is operating, the operating voltage difference and operating phase difference between the first line and the second line are obtained;

[0147] The regulating voltage is determined and adjusted based on the operating voltage difference and the operating phase difference.

[0148] The various modules in the control device of the aforementioned transformer can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0149] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 6 As shown, the computer device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage media. The input / output interface is used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When executed by the processor, the computer program implements a transformer control method. The display unit is used to form a visually visible image and can be a display screen, projection device, or virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0150] Those skilled in the art will understand that Figure 6 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0151] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions.

[0152] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0153] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0154] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A control method for a transformer, characterized in that, A loop transformer is applied to connect a first line and a second line, the loop transformer including a converter unit; the converter unit is used to output a regulated voltage to the loop line, the method comprising: Obtain the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line; The compensation voltage of the closed loop circuit is determined based on the voltage difference and the phase difference; and the adjustment voltage of the converter unit is determined based on the compensation voltage and the number of turns. Based on the regulated voltage, a drive control signal is generated, which is used to control the converter unit to output the regulated voltage.

2. The method according to claim 1, characterized in that, The process of obtaining the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line includes: Obtain the turns ratio of the closed-loop transformer; wherein the turns ratio is the ratio of the number of turns of the first winding to the number of turns of the second winding in the closed-loop transformer; The voltage and current data of the first line and the voltage and current data of the second line are obtained, and the voltage amplitude difference and phase difference between the first line and the second line are determined based on the voltage and current data of the first line and the second line.

3. The method according to claim 1, characterized in that, Determining the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference includes: The amplitude compensation component is determined based on the voltage difference; Based on the phase difference, determine the phase compensation component; The amplitude compensation component and the phase compensation component are superimposed to obtain the compensation voltage.

4. The method according to claim 1, characterized in that, The step of generating a drive control signal based on the adjusted voltage includes: A modulation signal is generated based on the adjusted voltage; The modulation signal is used as the drive control signal and output to the converter unit to control the on / off state of the converter unit's switching transistor, so that the converter unit outputs the regulated voltage.

5. The method according to claim 1, characterized in that, Determining the regulating voltage of the converter unit based on the compensation voltage and the number of turns includes: Obtain the turns ratio of the series compensation winding to the main winding in the closed-loop transformer; The initial voltage of the converter unit is determined based on the compensation voltage and the turns ratio. If the initial voltage exceeds a preset adjustment threshold, the preset adjustment threshold is determined as the adjustment voltage; If the initial voltage does not exceed the preset adjustment threshold, the initial voltage is determined as the adjustment voltage.

6. The method according to claim 1, characterized in that, The method further includes: When the converter unit is operating, the operating voltage difference and operating phase difference between the first line and the second line are obtained; The regulating voltage is determined and adjusted based on the operating voltage difference and the operating phase difference.

7. A control device for a transformer, characterized in that, A loop transformer for connecting a first line and a second line, the loop transformer including a converter unit; the converter unit is used to output a regulated voltage to the loop line, the device comprising: The data acquisition module is used to acquire the number of turns of the closed-loop transformer, the voltage difference and phase difference between the first line and the second line; A voltage determination module is used to determine the compensation voltage of the closed loop circuit based on the voltage difference and the phase difference; and to determine the adjustment voltage of the converter unit based on the compensation voltage and the number of turns. A voltage output module is used to generate a drive control signal based on the regulated voltage, and the drive control signal is used to control the converter unit to output the regulated voltage.

8. The apparatus according to claim 7, characterized in that, The closed-loop transformer also includes a series compensation winding; the series compensation winding and the main winding of the closed-loop transformer are wound on the same iron core column; and the series compensation winding and the main winding are spaced apart from each other in the axial direction of the iron core column.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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