A large inertia flywheel PRMB star coupling structure and a dual-mode control method

Abstract

The application provides a large-inertia flywheel PRMB star coupling structure and a dual-mode control method. The large-inertia flywheel PRMB star coupling structure comprises a plurality of stators, a plurality of windings, a plurality of running state detection components, a current shunt module, a controller, a permanent magnet and a large-inertia flywheel rotor. The plurality of windings are respectively wound on the plurality of stators. The plurality of running state detection components are respectively integrated at the end portions of the plurality of stators. One end of the plurality of windings and the plurality of running state detection components are respectively electrically connected to the controller. The other end of the plurality of windings is electrically connected to the controller through the current shunt module. The permanent magnet and the large-inertia flywheel rotor are located between the plurality of stators.

Description

Technical Field

[0001] This invention relates to the field of magnetic levitation flywheel control technology, and in particular to a large inertia flywheel PRMB star connection structure and a dual-mode control method. Background Technology

[0002] Currently, the levitation control of large-inertia flywheels mainly uses permanent magnet biased hybrid magnetic bearings (PRMB) as the core actuator. The stator mostly adopts an integrated four-tooth or six-tooth structure, and the permanent magnets are axially magnetized. A single controller is used to control multiple windings through group drive interfaces. The windings adopt a single stator winding method, and the windings between the left and right stators are connected in series or parallel. The controller integrates "control-monitoring-protection-diagnosis" functions and works with an external main control system to maintain the stable operation of the magnetic levitation system. Displacement sensors are installed at the stator magnetic poles to collect rotor levitation displacement signals to determine whether the rotor deviates from the center position and trigger current adjustment commands. Temperature sensors are added to monitor the temperature of key components such as the control windings, protective bearings, and three-phase motor windings.

[0003] Based on the above-mentioned existing technology implementation schemes and existing technical problems, the specific shortcomings of the existing technology can be divided into the following points: 1. Unreasonable control structure: The winding connection lacks dynamic current sharing design, resulting in uneven current distribution, which can easily lead to winding overload and large magnetic circuit loss.

[0004] 2. Low monitoring accuracy and weak anti-interference ability: The displacement sensor has no temperature drift compensation and mutual calibration mechanism, which cannot eliminate the influence of temperature on displacement monitoring; the signal transmission has no encryption and redundant backup, which makes it susceptible to electromagnetic interference, resulting in signal distortion and low system reliability.

[0005] 3. Poor adaptability of control strategy: A single control mode cannot adapt to the needs of different working stages of the stator motor. The suspension is unstable at low speed and the power consumption is too high at high speed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a large inertia flywheel PRMB star connection structure and a dual-mode control method.

[0007] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A large inertia flywheel PRMB star connection structure includes: multiple stators, multiple windings, multiple operating status detection components, a current shunt module, a controller, a permanent magnet, and a large inertia flywheel rotor. The multiple windings are respectively wound on the multiple stators, the multiple operating status detection components are respectively integrated at the ends of the multiple stators, one end of the multiple windings and the multiple operating status detection components are respectively electrically connected to the controller, and the other end of the multiple windings is electrically connected to the controller through the current shunt module. The permanent magnet and the large inertia flywheel rotor are located between the multiple stators.

[0008] The beneficial effects of adopting the technical solution of this invention are as follows: The "segmented magnetization + magnetic field homogenization" process improves the uniformity of magnetic flux distribution. A "cross-stator through-type + layered winding" structure is used, penetrating the corresponding magnetic poles of the left and right stators respectively; a star connection is adopted, with one end converging at a common zero point, and the other end connecting to the controller's independent control interface. The common end is connected to the controller's common interface through a high-precision current shunt module, enabling the controller to independently control and dynamically share current for each group of windings. All components work together to achieve stable levitation and dual-mode control of the flywheel rotor. The simplified control structure reduces costs and improves adaptability. A single controller integrated control + 4-group winding star connection design, along with a star connection and dynamic current sharing algorithm, ensures balanced current in each group of windings, avoids winding overload, and adapts to the levitation control requirements of large-inertia flywheels across the entire speed range.

[0009] Furthermore, the multiple stators are symmetrical to each other, and each stator has a four-tooth, two-pole structure. The stator is a high-permeability silicon steel sheet laminated structure. The permanent magnets are located between the multiple stators on the same side of the large-inertia flywheel rotor. There is a gap between the large-inertia flywheel rotor and the stator. Multiple windings pass through the magnetic poles of the multiple stators respectively. The controller is equipped with a common interface and multiple independent interfaces. One end of each winding is electrically connected to the multiple independent interfaces, and the other end of each winding is electrically connected to the common interface through a current shunt module.

[0010] The beneficial effects of adopting the above-mentioned further technical solution are as follows: the left and right stators are symmetrically arranged, both with a four-tooth, two-pole structure, and are made of high-permeability silicon steel sheets laminated together; the axially magnetized annular permanent magnet is located between the left and right stators, and adopts a "segmented magnetization + magnetic field homogenization" process to improve the uniformity of magnetic flux distribution. A "cross-stator through-type + layered winding" structure is adopted, penetrating the corresponding magnetic poles of the left and right stators respectively; a star connection method is used, with one end converging at a common zero point, and the other end connected to the controller's independent control interface. The common end is connected to the controller's common interface through a high-precision current shunt module, realizing the controller's independent control and dynamic current sharing of each winding group. Both the left and right stators have a four-tooth, two-pole structure, made of high-permeability silicon steel sheets laminated together, ensuring magnetic circuit efficiency; the central axially magnetized annular permanent magnet provides bias magnetic flux for the entire magnetic bearing; the large-inertia flywheel rotor is located at the center of the PRMB, maintaining a 0.2mm suspension gap with the stator, and the rotor surface is treated with anti-friction to avoid mechanical damage in case of abnormal suspension. Four sets of shared windings with the same pole are made of high-conductivity copper wire, respectively wound through the corresponding magnetic poles of the left and right stators. This ensures that when current is applied, the core requirement of "reverse magnetic flux of corresponding magnetic poles on the left and right sides and same magnetic flux of opposite magnetic poles" can be achieved, laying the structural foundation for star connection control. One end of the four windings converges to form a common terminal, which is connected in series with a high-precision current shunt module to achieve precise current distribution and return current regulation, ensuring that the current of the four windings is independent and does not interfere with each other, with current fluctuation controlled within ±2%. The other end of the shunt module is connected to the controller's common interface. The other end of the four windings serves as an independent control terminal, connected to the controller's four independent control channels, forming an electrical structure of "common zero point + four independent branches," enabling independent and precise adjustment of a single winding and providing structural support for dual-mode control.

[0011] Furthermore, the operating status detection component includes: a displacement sensor and a temperature sensing unit. The displacement sensor is embedded at the end of the stator, and the temperature sensing unit is built into the displacement sensor. A speed sensor and a vibration sensor are provided at the end of the stator. The displacement sensor, temperature sensing unit, speed sensor, and vibration sensor are all electrically connected to the controller. The current shunt module integrates a current sensor and an alarm unit, both of which are electrically connected to the controller. The controller has a built-in signal acquisition module, a mode switching judgment module, a dual-mode control module, a protection module, and a fault diagnosis module.

[0012] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: four high-precision displacement sensors are embedded in the stator ends, with built-in miniature temperature sensing units to achieve synchronous acquisition of displacement and temperature; a "displacement-temperature-magnetic circuit" linkage calibration algorithm is introduced to achieve displacement drift compensation and magnetic flux calculation. Real-time acquisition and anomaly early warning functions are integrated, with real-time acquisition of total current and current of each branch, with an accuracy of ≤±1%, preset current thresholds, and triggering early warnings in case of anomalies. A high-performance microcontroller is used, integrating "control-monitoring-protection-diagnosis" functions, with built-in modules for signal acquisition, mode switching judgment, dual-mode control, hierarchical protection, and fault diagnosis, achieving fully automated control of the entire process. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, which improves displacement monitoring accuracy. Combined with the operating condition optimized temperature compensation strategy, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is adopted, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0013] Furthermore, this invention also provides a dual-mode control method for a large inertia flywheel. Based on the aforementioned PRMB star connection structure of a large inertia flywheel, the dual-mode control method includes: S1, detecting the operating state of the large inertia flywheel through multiple operating state detection components; S2, switching between constant torque mode and constant power mode by the controller according to the operating state of the large inertia flywheel; S3, when switching to constant torque mode, controlling through dual closed-loop control logic; S4, when switching to constant power mode, controlling through constant power mode control logic.

[0014] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: four high-precision displacement sensors are embedded in the stator ends, with built-in miniature temperature sensing units to achieve synchronous acquisition of displacement and temperature; a "displacement-temperature-magnetic circuit" linkage calibration algorithm is introduced to achieve displacement drift compensation and magnetic flux calculation. Real-time acquisition and anomaly early warning functions are integrated, with real-time acquisition of total current and current of each branch, with an accuracy of ≤±1%, preset current thresholds, and triggering early warnings in case of anomalies. A high-performance microcontroller is used, integrating "control-monitoring-protection-diagnosis" functions, with built-in modules for signal acquisition, mode switching judgment, dual-mode control, hierarchical protection, and fault diagnosis, achieving fully automated control of the entire process. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, enhancing displacement monitoring accuracy. Combined with an optimized temperature compensation strategy based on operating conditions, simple compensation is used during the constant torque start-up phase due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation phase, due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is employed, reducing errors after temperature drift compensation. Displacement-current dual closed-loop collaborative control, coupled with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppressing rotor displacement fluctuations and significantly enhancing disturbance rejection capability, solving the problems of levitation instability at low speeds and the impact of temperature drift on accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are achieved. The dual-mode control strategy precisely adapts to the constant torque and constant power operating phases of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. Adaptive mode switching + smooth current transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0015] Further, step S1 includes: acquiring winding current signals through a current shunt module, acquiring rotor suspension displacement signals through a displacement sensor, acquiring rotor speed signals through a speed sensor, acquiring flywheel vibration signals through a vibration sensor, and acquiring winding temperature signals through a temperature sensor; step S2 includes: the controller automatically determines whether to switch to constant torque mode or constant power mode based on the winding current signal, rotor suspension displacement signal, rotor speed signal, flywheel vibration signal, and winding temperature signal through a mode switching judgment module; and monitors the status of each component through a protection module, triggering protection and alarms when abnormalities occur; step S3 includes: driving the winding to work through a constant torque mode control unit, cooperating with the flywheel drive unit to realize the start-up, stable operation, and shutdown of the flywheel; or, driving the winding to work through a constant power mode control unit, cooperating with the flywheel drive unit to realize the start-up, stable operation, and shutdown of the flywheel.

[0016] The beneficial effects of adopting the above-mentioned further technical solution are as follows: Through detection modules for speed, current, displacement, temperature, and vibration, the flywheel operating status signals are collected in real time, and key data such as winding current, rotor suspension displacement, flywheel vibration, and winding temperature are fed back in real time, providing dual core support for control decisions. Based on the input and feedback signals, the controller automatically determines whether to switch to constant torque mode or constant power mode through the mode switching unit. The execution module drives the windings according to the controller's instructions, cooperating with the flywheel drive unit to achieve flywheel start-up, stable operation, and shutdown. The protection module monitors the status of each component in real time, immediately triggering protection and alarms in case of abnormalities to ensure equipment safety. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, enhancing displacement monitoring accuracy. Combined with an optimized temperature compensation strategy based on operating conditions, simple compensation is used during the constant torque start-up phase due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation phase, due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is employed, reducing errors after temperature drift compensation. Displacement-current dual closed-loop collaborative control, coupled with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppressing rotor displacement fluctuations and significantly enhancing disturbance rejection capability, solving the problems of levitation instability at low speeds and the impact of temperature drift on accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are achieved. The dual-mode control strategy precisely adapts to the constant torque and constant power operating phases of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. Adaptive mode switching + smooth current transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0017] Further, step S3 includes: S31, acquiring rotor displacement signals through a displacement sensor and correcting displacement deviations through a temperature compensation module; S32, determining whether the actual displacement exceeds a preset threshold through a controller; S33, when the actual displacement exceeds the preset threshold, the levitation is unstable, and the inner current loop adjustment is initiated; S34, outputting the corresponding current adjustment amount according to the displacement deviation; S35, acquiring and processing current data; S36, determining whether the current exceeds a preset range and deviation; S37, when the current exceeds a preset range and deviation, adjusting the winding drive voltage; S38, dynamically sharing current and fine-tuning the current; S39, performing magnetic circuit compensation based on displacement and temperature until the rotor is stably levitated.

[0018] The beneficial effect of adopting the above-mentioned further technical solution is that the displacement-current dual closed-loop control adopts a collaborative logic of "outer closed-loop dominance, inner closed-loop support, and magnetic circuit compensation assistance". The core related logic is: the outer closed loop determines the target value of current regulation, the inner closed loop realizes the precise regulation and balancing of current, and the magnetic circuit compensation module fine-tunes the current according to displacement and temperature signals to further optimize the magnetic circuit state. Together, they form a complete closed loop of "displacement monitoring - deviation calculation - current regulation - magnetic circuit compensation - displacement feedback" to ensure control accuracy and stability. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, which improves displacement monitoring accuracy. Combined with the operating condition optimized temperature compensation strategy, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is adopted, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0019] Further, after step S32, when the actual displacement does not exceed the preset threshold, the system stabilizes and maintains the current winding current, and then executes step S35; after step S36, when the current does not exceed the preset range and deviation, step S39 is executed.

[0020] The beneficial effect of adopting the above-mentioned further technical solution is that the displacement-current dual closed-loop control adopts a collaborative logic of "outer closed-loop dominance, inner closed-loop support, and magnetic circuit compensation assistance". The core related logic is: the outer closed loop determines the target value of current regulation, the inner closed loop realizes the precise regulation and balancing of current, and the magnetic circuit compensation module fine-tunes the current according to displacement and temperature signals to further optimize the magnetic circuit state. Together, they form a complete closed loop of "displacement monitoring - deviation calculation - current regulation - magnetic circuit compensation - displacement feedback" to ensure control accuracy and stability. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, which improves displacement monitoring accuracy. Combined with the operating condition optimized temperature compensation strategy, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is adopted, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0021] Further, step S4 includes: S41, constant power mode confirmation; S42, multi-parameter synchronous acquisition and processing; S43, parameter threshold judgment; S44, current precise fine-tuning execution; S45, magnetic circuit adaptive optimization; S46, temperature compensation linkage; S47, steady-state judgment and feedback.

[0022] The beneficial effects of adopting the above-mentioned further technical solutions are: improved control accuracy and anti-disturbance capability; improved displacement monitoring accuracy through displacement-temperature collaborative sensing and magnetic circuit flux calculation design; optimized temperature compensation strategy based on operating conditions; simple compensation for low temperature and small temperature drift during constant torque start-up, focusing on suppressing displacement fluctuations; and high-precision real-time dynamic compensation for high temperature rise and large temperature drift during long-term constant power operation, reducing errors after temperature drift compensation; and displacement-current dual closed-loop collaborative control, combined with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppresses rotor displacement fluctuations, and significantly enhances anti-disturbance capability, solving the problems of levitation instability at low speeds and temperature drift affecting accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are also achieved. The dual-mode control strategy accurately adapts to the constant torque and constant power operating stages of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. The adaptive mode switching and current smooth transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0023] Further, step S41 includes: when the flywheel speed is consistently not less than the base speed, the displacement fluctuation is not greater than the preset displacement fluctuation, and the winding current is stable below the preset winding current, the controller's mode switching judgment unit confirms entry into constant power mode, synchronously issues a mode switching command, closes the high-frequency displacement adjustment logic of constant torque mode, and starts the constant power mode control program; step S42 includes: the displacement sensor and temperature sensing unit collect rotor suspension displacement, winding temperature, and ambient temperature; the current shunt module collects the current of each branch of the four windings and the total current; the speed sensor collects the real-time speed, and all parameters are synchronously transmitted to the controller's signal acquisition module for filtering and noise reduction processing to eliminate high-frequency interference signals; step S43 includes: S431, judging whether the displacement exceeds the preset displacement threshold; S432, when the displacement does not exceed the preset displacement threshold, the suspension is stable; S433, synchronously performing current judgment and temperature judgment; S434, when the total current is too small or too large, finely adjusting the total current to maintain the suspension force; when the temperature rise is greater than When the first preset temperature rise occurs, temperature compensation and current fine-tuning are simultaneously activated. Step S44 includes: based on the parameter judgment result, the dual-mode control unit of the controller outputs a precise current adjustment command, and performs differentiated fine-tuning on the four windings through an independent control interface. Step S45 includes: S451, calculating the ratio of bias flux to control flux in real time to ensure that the ratio of bias flux is stable within the first preset ratio range and the ratio of control flux is maintained within the second preset ratio range. When flux fluctuation is detected to be no less than the preset deviation, the flux distribution is corrected by fine-tuning the control current to avoid a decrease in magnetic circuit stiffness. S452, the current adjustment frequency is adaptively adjusted according to the winding temperature change, and the winding heat dissipation structure is linked to reduce steady-state temperature rise and further reduce magnetic circuit loss. Step S46 includes: synchronized with magnetic circuit optimization and current fine-tuning, the displacement error caused by temperature drift is corrected once every preset time through displacement, temperature and magnetic circuit linkage calibration algorithm. Step S47 includes: the controller performs secondary acquisition and judgment on the adjusted parameters to form closed-loop control.

[0024] The beneficial effects of adopting the above-mentioned further technical solutions are: improved control accuracy and anti-disturbance capability; improved displacement monitoring accuracy through displacement-temperature collaborative sensing and magnetic circuit flux calculation design; optimized temperature compensation strategy based on operating conditions; simple compensation for low temperature and small temperature drift during constant torque start-up, focusing on suppressing displacement fluctuations; and high-precision real-time dynamic compensation for high temperature rise and large temperature drift during long-term constant power operation, reducing errors after temperature drift compensation; and displacement-current dual closed-loop collaborative control, combined with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppresses rotor displacement fluctuations, and significantly enhances anti-disturbance capability, solving the problems of levitation instability at low speeds and temperature drift affecting accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are also achieved. The dual-mode control strategy accurately adapts to the constant torque and constant power operating stages of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. The adaptive mode switching and current smooth transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0025] Further, in step S41, the preset displacement fluctuation is 0.005mm, and the preset winding current is 2A; after step S431, the following steps are included: when the displacement exceeds the preset displacement threshold, the rotor deflects, triggering the current fine-tuning priority, fine-tuning the corresponding magnetic pole winding current, and pushing the rotor back to the center position by controlling the slight change in magnetic flux to avoid magnetic circuit impact caused by sudden current changes; in step S432, the preset displacement threshold is 0.005mm; step S434 includes: for scenarios where the displacement is ≤0.005mm; when the current deviation of each branch is >±0.3A, dynamic current sharing fine-tuning is initiated, without changing the total current, only adjusting the current distribution of each branch to avoid affecting levitation; when the total current is >2A, a current reduction command is triggered to slightly reduce the total current, while maintaining levitation force through magnetic circuit optimization to ensure that the displacement does not deviate from the threshold ... When the current is <1A, the current is appropriately increased to slightly raise the total current to the standard range to avoid insufficient levitation force leading to subsequent displacement deviation; if the winding temperature rise is ≥5℃, temperature compensation and current fine-tuning are activated simultaneously; if the winding temperature rise is ≥10℃, the current is preferentially reduced by 0.1-0.2A, and then temperature compensation is strengthened; in step S451, the first preset percentage range is 70%-80%, the second preset percentage range is 20%-30%, and the preset deviation is 5%; in step S46, the preset time is 10ms; step S46 includes: temperature drift correction: calculate the displacement deviation compensation amount based on the difference between the winding temperature and the ambient temperature, correct the displacement monitoring data in real time, and ensure that the displacement monitoring accuracy is maintained within ±0.001mm; compensation strength adjustment: the higher the winding temperature rise, the greater the compensation strength, to avoid magnetic circuit deviation and rotor displacement caused by temperature drift.

[0026] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: Displacement judgment: If the displacement is >0.005mm, the rotor shifts in a certain direction, triggering the current fine-tuning priority, fine-tuning the current of the corresponding magnetic pole winding, and pushing the rotor back to the center position by controlling the slight change in magnetic flux, avoiding magnetic circuit impact caused by sudden current changes; If the displacement is ≤0.005mm, the current base value is maintained, the focus is on magnetic circuit optimization, and the current status is judged at the same time. Current judgment: For the scenario of "displacement ≤0.005mm", three abnormal situations are subdivided and the adjustment direction is clarified: ① Current deviation of each branch >±0.3A: Dynamic current sharing fine-tuning is initiated, the core of which is "differentiated fine-tuning + synchronous displacement monitoring", without changing the total current, only adjusting the current distribution of each branch to avoid affecting levitation; ② Total current >2A: The current reduction command is triggered, using "slow fine-tuning + magnetic circuit compensation", slightly reducing the total current, while maintaining levitation force through magnetic circuit optimization to ensure that the displacement does not deviate from the threshold; ③ Total current <1A: The current is appropriately increased, slightly increasing the total current to the standard range to avoid insufficient levitation force leading to subsequent displacement deviation. Temperature Judgment: If the winding temperature rise is ≥5℃, temperature compensation and current fine-tuning are activated simultaneously; if the winding temperature rise is ≥10℃, the current is reduced by 0.1-0.2A first, and then temperature compensation is strengthened. Magnetic Flux Distribution Optimization: The ratio of bias flux to control flux is calculated in real time to ensure that the bias flux ratio is stable at 70%-80% and the control flux ratio is maintained at 20%-30%. When flux fluctuations are detected, the flux distribution is corrected by fine-tuning the control current to avoid a decrease in magnetic circuit stiffness. Especially during total current adjustment, flux distribution optimization compensates for levitation force, ensuring stable displacement. Magnetic Circuit Loss Optimization: The current regulation frequency is adaptively adjusted according to the winding temperature change, and the winding heat dissipation structure is linked to reduce steady-state temperature rise, further reducing magnetic circuit losses. Temperature Drift Correction: The displacement deviation compensation is calculated based on the difference between the winding temperature and the ambient temperature, and the displacement monitoring data is corrected in real time to ensure that the displacement monitoring accuracy is maintained within ±0.001mm. Compensation strength adjustment: The higher the winding temperature rise, the greater the compensation strength, to avoid magnetic circuit deviation and rotor displacement caused by temperature drift.

[0027] The advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1This is one of the schematic diagrams of the PRMB structure and the wiring of the common winding with the same pole provided in the embodiments of the present invention.

[0030] Figure 2 This is the second schematic diagram of the PRMB structure and the wiring diagram of the common winding with the same pole provided in the embodiment of the present invention.

[0031] Figure 3 This is one of the schematic diagrams of the PRMB magnetic circuit provided in the embodiments of the present invention.

[0032] Figure 4 This is the second schematic diagram of the PRMB magnetic circuit provided in the embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram of the star connection of the PRMB same-pole winding provided in an embodiment of the present invention.

[0034] Figure 6 This is a schematic diagram of the dual-mode control logic provided in an embodiment of the present invention.

[0035] Figure 7 This is a schematic diagram of the dual closed-loop control logic provided in an embodiment of the present invention.

[0036] Figure 8 This is a schematic diagram of the constant power mode control logic provided in an embodiment of the present invention.

[0037] The following are the symbols in the attached diagram: 1. Stator; 2. Winding; 3. Current shunt module; 4. Controller; 5. Permanent magnet; 6. High inertia flywheel rotor; 7. Clearance; 8. Common interface; 9. Independent interface. Detailed Implementation

[0038] The principles and features of the present invention are described below with reference to the accompanying drawings. The embodiments described are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0039] like Figures 1 to 5 As shown, this embodiment of the invention provides a large inertia flywheel PRMB star connection structure, including: multiple stators 1, multiple windings 2, multiple operating status detection components, a current shunt module 3, a controller 4, a permanent magnet 5, and a large inertia flywheel rotor 6. The multiple windings 2 are respectively wound on the multiple stators 1, the multiple operating status detection components are respectively integrated at the ends of the multiple stators 1, one end of the multiple windings 2 and the multiple operating status detection components are respectively electrically connected to the controller 4, and the other end of the multiple windings 2 are all electrically connected to the controller 4 through the current shunt module 3. The permanent magnet 5 and the large inertia flywheel rotor 6 are both located between the multiple stators 1.

[0040] The beneficial effects of adopting the technical solution of this invention are as follows: The "segmented magnetization + magnetic field homogenization" process improves the uniformity of magnetic flux distribution. A "cross-stator through-type + layered winding" structure is used, penetrating the corresponding magnetic poles of the left and right stators respectively; a star connection is adopted, with one end converging at a common zero point, and the other end connecting to the controller's independent control interface. The common end is connected to the controller's common interface through a high-precision current shunt module, enabling the controller to independently control and dynamically share current for each group of windings. All components work together to achieve stable levitation and dual-mode control of the flywheel rotor. The simplified control structure reduces costs and improves adaptability. A single controller integrated control + 4-group winding star connection design, along with a star connection and dynamic current sharing algorithm, ensures balanced current in each group of windings, avoids winding overload, and adapts to the levitation control requirements of large-inertia flywheels across the entire speed range.

[0041] like Figures 1 to 5 As shown, further, multiple stators 1 are symmetrical to each other, and each stator 1 has a four-tooth two-pole structure. The stator 1 is a high-permeability silicon steel sheet stacked structure. The permanent magnet 5 is located between multiple stators 1 on the same side of the large inertia flywheel rotor 6. There is a gap 7 between the large inertia flywheel rotor 6 and the stator 1. Multiple windings 2 pass through the magnetic poles of multiple stators 1 respectively. The controller 4 is equipped with a common interface 8 and multiple independent interfaces 9. One end of multiple windings 2 is electrically connected to multiple independent interfaces 9 respectively, and the other end of multiple windings 2 is electrically connected to the common interface 9 through the current shunt module 3.

[0042] The beneficial effects of adopting the above-mentioned further technical solution are as follows: the left and right stators are symmetrically arranged, both with a four-tooth, two-pole structure, and are made of high-permeability silicon steel sheets laminated together; the axially magnetized annular permanent magnet is located between the left and right stators, and adopts a "segmented magnetization + magnetic field homogenization" process to improve the uniformity of magnetic flux distribution. A "cross-stator through-type + layered winding" structure is adopted, penetrating the corresponding magnetic poles of the left and right stators respectively; a star connection method is used, with one end converging at a common zero point, and the other end connected to the controller's independent control interface. The common end is connected to the controller's common interface through a high-precision current shunt module, realizing the controller's independent control and dynamic current sharing of each winding group. Both the left and right stators have a four-tooth, two-pole structure, made of high-permeability silicon steel sheets laminated together, ensuring magnetic circuit efficiency; the central axially magnetized annular permanent magnet provides bias magnetic flux for the entire magnetic bearing; the large-inertia flywheel rotor is located at the center of the PRMB, maintaining a 0.2mm suspension gap with the stator, and the rotor surface is treated with anti-friction to avoid mechanical damage in case of abnormal suspension. Four sets of shared windings with the same pole are made of high-conductivity copper wire, respectively wound through the corresponding magnetic poles of the left and right stators. This ensures that when current is applied, the core requirement of "reverse magnetic flux of corresponding magnetic poles on the left and right sides and same magnetic flux of opposite magnetic poles" can be achieved, laying the structural foundation for star connection control. One end of the four windings converges to form a common terminal, which is connected in series with a high-precision current shunt module to achieve precise current distribution and return current regulation, ensuring that the current of the four windings is independent and does not interfere with each other, with current fluctuation controlled within ±2%. The other end of the shunt module is connected to the controller's common interface. The other end of the four windings serves as an independent control terminal, connected to the controller's four independent control channels, forming an electrical structure of "common zero point + four independent branches," enabling independent and precise adjustment of a single winding and providing structural support for dual-mode control.

[0043] The gap can be an air gap.

[0044] like Figures 1 to 5 As shown, the operating status detection component further includes: a displacement sensor and a temperature sensing unit. The displacement sensor is embedded at the end of the stator 1, and the temperature sensing unit is built into the displacement sensor. A speed sensor and a vibration sensor are provided at the end of the stator 1. The displacement sensor, temperature sensing unit, speed sensor, and vibration sensor are all electrically connected to the controller 4. The current shunt module integrates a current sensor and an alarm unit, and the current sensor and alarm unit are both electrically connected to the controller. The controller has a built-in signal acquisition module, a mode switching judgment module, a dual-mode control module, a protection module, and a fault diagnosis module.

[0045] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: four high-precision displacement sensors are embedded in the stator ends, with built-in miniature temperature sensing units to achieve synchronous acquisition of displacement and temperature; a "displacement-temperature-magnetic circuit" linkage calibration algorithm is introduced to achieve displacement drift compensation and magnetic flux calculation. Real-time acquisition and anomaly early warning functions are integrated, with real-time acquisition of total current and current of each branch, with an accuracy of ≤±1%, preset current thresholds, and triggering early warnings in case of anomalies. A high-performance microcontroller is used, integrating "control-monitoring-protection-diagnosis" functions, with built-in modules for signal acquisition, mode switching judgment, dual-mode control, hierarchical protection, and fault diagnosis, achieving fully automated control of the entire process. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, which improves displacement monitoring accuracy. Combined with the operating condition optimized temperature compensation strategy, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is adopted, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0046] like Figures 6 to 8 As shown, this invention also provides a dual-mode control method for a large inertia flywheel. Based on the aforementioned PRMB star connection structure of a large inertia flywheel, the dual-mode control method includes: S1, detecting the operating state of the large inertia flywheel through multiple operating state detection components; S2, switching between constant torque mode and constant power mode by the controller according to the operating state of the large inertia flywheel; S3, when switching to constant torque mode, controlling through dual closed-loop control logic; S4, when switching to constant power mode, controlling through constant power mode control logic.

[0047] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: four high-precision displacement sensors are embedded in the stator ends, with built-in miniature temperature sensing units to achieve synchronous acquisition of displacement and temperature; a "displacement-temperature-magnetic circuit" linkage calibration algorithm is introduced to achieve displacement drift compensation and magnetic flux calculation. Real-time acquisition and anomaly early warning functions are integrated, with real-time acquisition of total current and current of each branch, with an accuracy of ≤±1%, preset current thresholds, and triggering early warnings in case of anomalies. A high-performance microcontroller is used, integrating "control-monitoring-protection-diagnosis" functions, with built-in modules for signal acquisition, mode switching judgment, dual-mode control, hierarchical protection, and fault diagnosis, achieving fully automated control of the entire process. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, enhancing displacement monitoring accuracy. Combined with an optimized temperature compensation strategy based on operating conditions, simple compensation is used during the constant torque start-up phase due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation phase, due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is employed, reducing errors after temperature drift compensation. Displacement-current dual closed-loop collaborative control, coupled with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppressing rotor displacement fluctuations and significantly enhancing disturbance rejection capability, solving the problems of levitation instability at low speeds and the impact of temperature drift on accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are achieved. The dual-mode control strategy precisely adapts to the constant torque and constant power operating phases of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. Adaptive mode switching + smooth current transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0048] like Figures 6 to 8 As shown, further, step S1 includes: acquiring winding current signals through a current shunt module, acquiring rotor suspension displacement signals through a displacement sensor, acquiring rotor speed signals through a speed sensor, acquiring flywheel vibration signals through a vibration sensor, and acquiring winding temperature signals through a temperature sensor; step S2 includes: the controller automatically determines whether to switch to constant torque mode or constant power mode based on the winding current signal, rotor suspension displacement signal, rotor speed signal, flywheel vibration signal, and winding temperature signal through a mode switching judgment module; and monitors the status of each component through a protection module, triggering protection and alarms when abnormalities occur; step S3 includes: driving the winding to work through a constant torque mode control unit, cooperating with the flywheel drive unit to realize the start-up, stable operation, and shutdown of the flywheel; or, driving the winding to work through a constant power mode control unit, cooperating with the flywheel drive unit to realize the start-up, stable operation, and shutdown of the flywheel.

[0049] The beneficial effects of adopting the above-mentioned further technical solution are as follows: Through detection modules for speed, current, displacement, temperature, and vibration, the flywheel operating status signals are collected in real time, and key data such as winding current, rotor suspension displacement, flywheel vibration, and winding temperature are fed back in real time, providing dual core support for control decisions. Based on the input and feedback signals, the controller automatically determines whether to switch to constant torque mode or constant power mode through the mode switching unit. The execution module drives the windings according to the controller's instructions, cooperating with the flywheel drive unit to achieve flywheel start-up, stable operation, and shutdown. The protection module monitors the status of each component in real time, immediately triggering protection and alarms in case of abnormalities to ensure equipment safety. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, enhancing displacement monitoring accuracy. Combined with an optimized temperature compensation strategy based on operating conditions, simple compensation is used during the constant torque start-up phase due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation phase, due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is employed, reducing errors after temperature drift compensation. Displacement-current dual closed-loop collaborative control, coupled with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppressing rotor displacement fluctuations and significantly enhancing disturbance rejection capability, solving the problems of levitation instability at low speeds and the impact of temperature drift on accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are achieved. The dual-mode control strategy precisely adapts to the constant torque and constant power operating phases of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. Adaptive mode switching + smooth current transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0050] like Figures 6 to 8 As shown, step S3 further includes: S31, acquiring rotor displacement signals through a displacement sensor and correcting displacement deviations through a temperature compensation module; S32, determining whether the actual displacement exceeds a preset threshold through a controller; S33, when the actual displacement exceeds the preset threshold, the suspension is unstable, and the inner current loop adjustment is initiated; S34, outputting the corresponding current adjustment amount according to the displacement deviation; S35, acquiring and processing current data; S36, determining whether the current exceeds a preset range and deviation; S37, when the current exceeds a preset range and deviation, adjusting the winding drive voltage; S38, dynamic current sharing and fine-tuning of the current; S39, performing magnetic circuit compensation based on displacement and temperature until the rotor is stably suspended.

[0051] The beneficial effect of adopting the above-mentioned further technical solution is that the displacement-current dual closed-loop control adopts a collaborative logic of "outer closed-loop dominance, inner closed-loop support, and magnetic circuit compensation assistance". The core related logic is: the outer closed loop determines the target value of current regulation, the inner closed loop realizes the precise regulation and balancing of current, and the magnetic circuit compensation module fine-tunes the current according to displacement and temperature signals to further optimize the magnetic circuit state. Together, they form a complete closed loop of "displacement monitoring - deviation calculation - current regulation - magnetic circuit compensation - displacement feedback" to ensure control accuracy and stability. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, which improves displacement monitoring accuracy. Combined with the operating condition optimized temperature compensation strategy, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is adopted, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0052] like Figures 6 to 8 As shown, further, after step S32, when the actual displacement does not exceed the preset threshold, the system is stably suspended, the current winding current is maintained, and step S35 is executed; after step S36, when the current does not exceed the preset range and deviation, step S39 is executed.

[0053] The beneficial effect of adopting the above-mentioned further technical solution is that the displacement-current dual closed-loop control adopts a collaborative logic of "outer closed-loop dominance, inner closed-loop support, and magnetic circuit compensation assistance". The core related logic is: the outer closed loop determines the target value of current regulation, the inner closed loop realizes the precise regulation and balancing of current, and the magnetic circuit compensation module fine-tunes the current according to displacement and temperature signals to further optimize the magnetic circuit state. Together, they form a complete closed loop of "displacement monitoring - deviation calculation - current regulation - magnetic circuit compensation - displacement feedback" to ensure control accuracy and stability. To improve control accuracy and disturbance rejection capability, a displacement-temperature collaborative sensing + magnetic circuit flux calculation design is adopted, which improves displacement monitoring accuracy. Combined with the operating condition optimized temperature compensation strategy, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is adopted, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0054] like Figures 6 to 8As shown, step S4 further includes: S41, constant power mode confirmation; S42, multi-parameter synchronous acquisition and processing; S43, parameter threshold judgment; S44, current precise fine-tuning execution; S45, magnetic circuit adaptive optimization; S46, temperature compensation linkage; S47, steady-state judgment and feedback.

[0055] The beneficial effects of adopting the above-mentioned further technical solutions are: improved control accuracy and anti-disturbance capability; improved displacement monitoring accuracy through displacement-temperature collaborative sensing and magnetic circuit flux calculation design; optimized temperature compensation strategy based on operating conditions; simple compensation for low temperature and small temperature drift during constant torque start-up, focusing on suppressing displacement fluctuations; and high-precision real-time dynamic compensation for high temperature rise and large temperature drift during long-term constant power operation, reducing errors after temperature drift compensation; and displacement-current dual closed-loop collaborative control, combined with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppresses rotor displacement fluctuations, and significantly enhances anti-disturbance capability, solving the problems of levitation instability at low speeds and temperature drift affecting accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are also achieved. The dual-mode control strategy accurately adapts to the constant torque and constant power operating stages of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. The adaptive mode switching and current smooth transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0056] like Figures 6 to 8As shown, further, step S41 includes: when the flywheel speed is continuously not less than the base speed, the displacement fluctuation is not greater than the preset displacement fluctuation, and the winding current is stable below the preset winding current, the controller's mode switching judgment unit confirms entry into constant power mode, synchronously issues a mode switching command, closes the high-frequency displacement adjustment logic of constant torque mode, and starts the constant power mode control program; step S42 includes: the displacement sensor and temperature sensing unit collect the rotor suspension displacement, winding temperature, and ambient temperature; the current shunt module collects the current of each branch of the four windings and the total current; the speed sensor collects the real-time speed, and all parameters are synchronously transmitted to the controller's signal acquisition module for filtering and noise reduction processing to eliminate high-frequency interference signals; step S43 includes: S431, judging whether the displacement exceeds the preset displacement threshold; S432, when the displacement does not exceed the preset displacement threshold, the suspension is stable; S433, synchronously performing current judgment and temperature judgment; S434, when the total current is too small or too large, finely adjusting the total current to maintain the suspension force; when the temperature rise is large... At the first preset temperature rise, temperature compensation and current fine-tuning are simultaneously initiated; Step S44 includes: based on the parameter judgment result, the dual-mode control unit of the controller outputs a precise current adjustment command, and performs differentiated fine-tuning on the four windings through an independent control interface; Step S45 includes: S451, real-time calculation of the ratio of bias flux to control flux to ensure that the ratio of bias flux is stable within the first preset ratio range and the ratio of control flux is maintained within the second preset ratio range. When flux fluctuation is detected to be no less than the preset deviation, the flux distribution is corrected by fine-tuning the control current to avoid a decrease in magnetic circuit stiffness; S452, the current adjustment frequency is adaptively adjusted according to the winding temperature change, and the winding heat dissipation structure is linked to reduce steady-state temperature rise and further reduce magnetic circuit loss; Step S46 includes: synchronously with magnetic circuit optimization and current fine-tuning, the displacement error caused by temperature drift is corrected once every preset time through displacement, temperature and magnetic circuit linkage calibration algorithm; Step S47 includes: the controller performs secondary acquisition and judgment on the adjusted parameters to form closed-loop control.

[0057] The beneficial effects of adopting the above-mentioned further technical solutions are: improved control accuracy and anti-disturbance capability; improved displacement monitoring accuracy through displacement-temperature collaborative sensing and magnetic circuit flux calculation design; optimized temperature compensation strategy based on operating conditions; simple compensation for low temperature and small temperature drift during constant torque start-up, focusing on suppressing displacement fluctuations; and high-precision real-time dynamic compensation for high temperature rise and large temperature drift during long-term constant power operation, reducing errors after temperature drift compensation; and displacement-current dual closed-loop collaborative control, combined with dynamic magnetic circuit compensation, improves magnetic circuit stiffness, rapidly suppresses rotor displacement fluctuations, and significantly enhances anti-disturbance capability, solving the problems of levitation instability at low speeds and temperature drift affecting accuracy at high speeds. Strong adaptability, smooth switching, and significantly improved energy efficiency are also achieved. The dual-mode control strategy accurately adapts to the constant torque and constant power operating stages of the stator motor, ensuring levitation stability at low speeds and reducing winding power consumption at high speeds. The adaptive mode switching and current smooth transition mechanism minimizes switching impact, avoids rotor misalignment faults, and achieves stable control throughout the entire process.

[0058] like Figures 6 to 8 As shown, further, in step S41, the preset displacement fluctuation is 0.005mm, and the preset winding current is 2A; after step S431, the following steps are included: when the displacement exceeds the preset displacement threshold, the rotor deflects, triggering the current fine-tuning priority, fine-tuning the corresponding magnetic pole winding current, and pushing the rotor back to the center position by controlling the slight change in magnetic flux to avoid magnetic circuit impact caused by sudden current changes; in step S432, the preset displacement threshold is 0.005mm; step S434 includes: for scenarios where the displacement is ≤0.005mm; when the current deviation of each branch is >±0.3A, dynamic current sharing fine-tuning is initiated, without changing the total current, only adjusting the current distribution of each branch to avoid affecting levitation; when the total current is >2A, a current reduction command is triggered to slightly reduce the total current, while maintaining levitation force through magnetic circuit optimization to ensure that the displacement does not deviate from the threshold ... When the current is <1A, the current is appropriately increased to slightly raise the total current to the standard range to avoid insufficient levitation force leading to subsequent displacement deviation; if the winding temperature rise is ≥5℃, temperature compensation and current fine-tuning are activated simultaneously; if the winding temperature rise is ≥10℃, the current is preferentially reduced by 0.1-0.2A, and then temperature compensation is strengthened; in step S451, the first preset percentage range is 70%-80%, the second preset percentage range is 20%-30%, and the preset deviation is 5%; in step S46, the preset time is 10ms; step S46 includes: temperature drift correction: calculate the displacement deviation compensation amount based on the difference between the winding temperature and the ambient temperature, correct the displacement monitoring data in real time, and ensure that the displacement monitoring accuracy is maintained within ±0.001mm; compensation strength adjustment: the higher the winding temperature rise, the greater the compensation strength, to avoid magnetic circuit deviation and rotor displacement caused by temperature drift.

[0059] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: Displacement judgment: If the displacement is >0.005mm, the rotor shifts in a certain direction, triggering the current fine-tuning priority, fine-tuning the current of the corresponding magnetic pole winding, and pushing the rotor back to the center position by controlling the slight change in magnetic flux, avoiding magnetic circuit impact caused by sudden current changes; If the displacement is ≤0.005mm, the current base value is maintained, the focus is on magnetic circuit optimization, and the current status is judged at the same time. Current judgment: For the scenario of "displacement ≤0.005mm", three abnormal situations are subdivided and the adjustment direction is clarified: ① Current deviation of each branch >±0.3A: Dynamic current sharing fine-tuning is initiated, the core of which is "differentiated fine-tuning + synchronous displacement monitoring", without changing the total current, only adjusting the current distribution of each branch to avoid affecting levitation; ② Total current >2A: The current reduction command is triggered, using "slow fine-tuning + magnetic circuit compensation", slightly reducing the total current, while maintaining levitation force through magnetic circuit optimization to ensure that the displacement does not deviate from the threshold; ③ Total current <1A: The current is appropriately increased, slightly increasing the total current to the standard range to avoid insufficient levitation force leading to subsequent displacement deviation. Temperature Judgment: If the winding temperature rise is ≥5℃, temperature compensation and current fine-tuning are activated simultaneously; if the winding temperature rise is ≥10℃, the current is reduced by 0.1-0.2A first, and then temperature compensation is strengthened. Magnetic Flux Distribution Optimization: The ratio of bias flux to control flux is calculated in real time to ensure that the bias flux ratio is stable at 70%-80% and the control flux ratio is maintained at 20%-30%. When flux fluctuations are detected, the flux distribution is corrected by fine-tuning the control current to avoid a decrease in magnetic circuit stiffness. Especially during total current adjustment, flux distribution optimization compensates for levitation force, ensuring stable displacement. Magnetic Circuit Loss Optimization: The current regulation frequency is adaptively adjusted according to the winding temperature change, and the winding heat dissipation structure is linked to reduce steady-state temperature rise, further reducing magnetic circuit losses. Temperature Drift Correction: The displacement deviation compensation is calculated based on the difference between the winding temperature and the ambient temperature, and the displacement monitoring data is corrected in real time to ensure that the displacement monitoring accuracy is maintained within ±0.001mm. Compensation strength adjustment: The higher the winding temperature rise, the greater the compensation strength, to avoid magnetic circuit deviation and rotor displacement caused by temperature drift.

[0060] In light of the practical requirements for large-inertia flywheel suspension control, this invention primarily addresses the following core technical issues: 1. Problems of poor adaptability and high cost of control structure: Existing technology adopts single controller group control, with windings simply connected in series or parallel, and cannot achieve dynamic current sharing of each group of windings. It is easy to cause problems such as overload of a single group of windings and uneven magnetic flux distribution in the magnetic circuit, which cannot adapt to the suspension control requirements of large inertia flywheels across the entire speed range.

[0061] 2. Problems of insufficient control accuracy and weak anti-disturbance capability: Existing technology uses displacement sensors to monitor displacement fluctuations, which are easily affected by temperature interference, resulting in large monitoring errors. There is no temperature drift compensation and mutual calibration mechanism, resulting in low displacement monitoring accuracy. During long-term operation, the heat of the winding itself seriously affects the displacement monitoring accuracy, making it difficult to meet the suspension stability requirements of large inertia flywheels during long-term operation.

[0062] 3. Poor control mode adaptability: Existing technology adopts a single control mode and does not carry out fine-grained adaptation design in combination with the constant torque (start-up, low speed) and constant power (high speed) working stages of the stator motor, resulting in unstable suspension in the low speed stage and high power consumption in the high speed stage.

[0063] This invention belongs to the field of magnetic levitation flywheel control technology, specifically involving a star-shaped connection structure and dual-mode control method for a large inertia flywheel PRMB (permanent magnet biased hybrid magnetic bearing). It is suitable for levitation control scenarios of large inertia flywheels and can achieve stable control of the flywheel from start-up to high-speed operation, improving control accuracy and energy efficiency. It is especially suitable for fields with high requirements for flywheel operation stability, such as energy storage and inertial navigation.

[0064] This invention addresses the shortcomings of existing technologies by constructing an integrated control system encompassing structure, control strategy, monitoring, and protection. The specific technical solution is as follows: (I) Overall Control Structure It includes the PRMB body, four sets of common windings with the same pole, displacement-temperature collaborative sensing components, high-precision current shunt module, single controller and high-inertia flywheel rotor. All components work together to achieve stable levitation and dual-mode control of the flywheel rotor.

[0065] 1. PRMB Body: The left and right stators are symmetrically arranged, both with a four-tooth two-pole structure, and are made of high-permeability silicon steel sheets. The axially magnetized annular permanent magnet is located between the left and right stators, and adopts the "segmented magnetization + magnetic field homogenization" process to improve the uniformity of magnetic flux distribution.

[0066] 2.4 sets of common pole windings: adopting a "through-stator + layered winding" structure, respectively passing through the corresponding magnetic poles of the left and right stators; adopting a star connection method, one end converges at the common terminal to a common zero point, and the other end is connected to the controller's independent control interface. The common terminal is connected to the controller's common interface through a high-precision current shunt module, realizing the controller's independent control and dynamic current sharing of each set of windings.

[0067] 3. Displacement-temperature co-sensing component: Four high-precision displacement sensors are embedded in the stator end, with built-in miniature temperature sensing units to achieve synchronous acquisition of displacement and temperature; a "displacement-temperature-magnetic circuit" linkage calibration algorithm is introduced to achieve displacement drift compensation and magnetic circuit flux calculation.

[0068] 4. High-precision current shunt module: integrates real-time acquisition and abnormal warning functions, collects the total current and the current of each branch in real time with an accuracy of ≤±1%, preset current threshold, and triggers an alarm when there is an abnormality.

[0069] 5. Controller: It adopts a high-performance microcontroller that integrates "control-monitoring-protection-diagnosis" functions. It has built-in modules for signal acquisition, mode switching judgment, dual-mode control, hierarchical protection, and fault diagnosis to achieve fully automated control of the entire process.

[0070] (ii) Dual-mode control strategy Using the motor's base speed as the dividing line, the system adapts to two operating stages of the stator motor: constant torque (0-base speed) and constant power (>base speed), achieving adaptive and smooth switching. Adaptive switching is achieved by combining speed, displacement fluctuation, and current magnitude. A current smoothing transition algorithm is used during switching to avoid magnetic circuit impact and ensure rotor levitation stability (displacement fluctuation ≤ 0.003mm) during the switching process. Because the output characteristics of the stator motor and the flywheel operating state differ significantly between the two operating stages, the control objectives, core strategies, parameter settings, and magnetic circuit logic of the magnetic bearing are clearly different. A detailed explanation follows, clearly distinguishing the differences in magnetic bearing control between the two modes.

[0071] Constant torque mode (0-base speed) magnetic bearing control (adapted to flywheel start, low speed acceleration and low speed stable operation).

[0072] In this stage, the stator motor outputs constant torque. The core objective is to overcome the flywheel rotor inertia and maintain low-speed operation. The corresponding core requirements for magnetic bearing control are: to provide sufficient magnetic circuit stiffness, quickly suppress rotor displacement fluctuations (the rotor is easily affected by assembly eccentricity and motor torque fluctuations during startup and low-speed stages, resulting in large displacement fluctuations), ensure that the rotor does not collide with the stator, and at the same time take into account the anti-disturbance capability during startup, adapting to the load requirements of constant torque output of the stator motor.

[0073] Core control strategy: Employing a coordinated control system of displacement-current dual closed-loop feedback and dynamic magnetic circuit compensation, with displacement stability as the core guiding principle, precise adjustment is achieved through dual closed-loop linkage. The outer closed loop (displacement control) monitors the rotor's levitation displacement in real time and outputs current adjustment commands based on displacement deviations; the inner closed loop (current control) tracks these commands, precisely adjusting the winding current to ensure balanced current distribution, while simultaneously using dynamic magnetic circuit compensation to counteract the effects of temperature and magnetic flux fluctuations.

[0074] Current regulation logic: "Segmented adaptive current control" is adopted to dynamically adjust the winding current according to the speed range.

[0075] Start-up phase (0-300r / min): The stator motor outputs maximum torque to overcome rotor inertia. The magnetic bearings need to resist the disturbance caused by torque fluctuations. The 4 sets of windings are controlled to pass 6-7A current. Through the magnetic circuit characteristics of "the magnetic flux of the corresponding left and right magnetic poles is opposite and the magnetic flux of the opposite magnetic poles is in the same direction", the magnetic circuit stiffness is maximized and the rotor is quickly adjusted to the center suspension position (displacement ≤0.02mm).

[0076] Low-speed stabilization stage (300-base speed): The rotor state tends to be stable, the stator motor maintains constant torque, the winding current is dynamically reduced to 2-3A, the power consumption is reduced while ensuring the suspension stiffness, and the dynamic current sharing algorithm is started to calibrate the current of each branch in real time to ensure that the current deviation is ≤±0.5A and avoid local magnetic flux concentration.

[0077] Magnetic circuit dominant logic: A "bias flux + control flux synergistic dominance" mode is adopted. The bias flux provided by the axially magnetized toroidal permanent magnet accounts for 50%-60%, while the control flux generated by the current flowing through the four windings accounts for 40%-50%. By superimposing the control flux and bias flux, the magnetic circuit stiffness is improved, enhancing the anti-disturbance capability. When an external disturbance (such as assembly eccentricity or slight impact) causes a displacement fluctuation >0.01mm, the corresponding winding current is rapidly increased (maximum not exceeding 7A) to quickly suppress the displacement fluctuation (response time ≤5ms).

[0078] Parameter settings: The preset displacement threshold is slightly larger (the fault tolerance range is slightly larger to adapt to the displacement fluctuation characteristics in the low-speed stage).

[0079] Auxiliary control: The displacement-temperature co-sensing component focuses on monitoring rotor displacement fluctuations and synchronously collects temperature data, but only performs basic recording and minor compensation. Because the flywheel temperature is low when it is first started, the temperature drift has minimal impact on displacement monitoring, so there is no need to invest excessive compensation resources. The core focus is on suppressing displacement fluctuations and improving magnetic circuit stiffness to ensure stable startup. Only when the temperature rises abnormally (deviating from the ambient temperature by ≥10℃) will simple temperature drift compensation be activated to avoid extreme temperature fluctuations affecting startup stability.

[0080] Constant power mode (> base speed) magnetic bearing control (adapted for high-speed and stable operation of flywheel).

[0081] During this stage, the stator motor outputs constant power and the speed continues to increase (above the base speed). The core objective is to maintain the high-speed stable suspension of the flywheel, reduce winding power consumption, improve control accuracy, and adapt to the low disturbance and low power consumption requirements during high-speed operation (the rotor inertia is fully established during the high-speed stage, and the displacement fluctuation is small, but the control accuracy requirements are higher, and power consumption needs to be reduced to improve system energy efficiency).

[0082] Core control strategy: Employing precise current fine-tuning combined with adaptive magnetic circuit optimization control, this strategy prioritizes low power consumption and high precision. It simplifies the adjustment frequency of the displacement closed-loop, focusing on optimizing current adjustment accuracy and magnetic circuit adaptability, forming a complete control logic of "acquisition-analysis-adjustment-feedback-optimization." Since the rotor inertia is fully established at high speeds, displacement fluctuations are minimal, eliminating the need for high-frequency displacement adjustment. Instead, precise control of the winding current and adaptive matching of the magnetic circuit state maintain magnetic circuit stability while minimizing winding power consumption, thus meeting the long-term high-speed stable operation requirements of the flywheel.

[0083] The core control logic is based on a magnetic circuit principle of "bias flux dominance and control flux fine-tuning." It combines multi-parameter analysis of speed, current, temperature, and displacement. Precise current fine-tuning corrects magnetic circuit deviations, and adaptive optimization of the magnetic circuit matches high-speed operating conditions. Simultaneously, a temperature compensation mechanism is implemented to offset temperature drift, ensuring both levitation accuracy and system energy efficiency meet standards. A key challenge is addressing the adjustment problem of "appropriate displacement but abnormal current"—when the rotor displacement is within a preset threshold (≤0.005mm) and levitation is stable, if large current deviations, excessively high or low total current occur, a coordinated adjustment method of "precise fine-tuning + synchronous displacement monitoring + magnetic circuit compensation" is used. This adjusts the current to the standard range without affecting rotor levitation, balancing levitation stability and low power consumption requirements.

[0084] Current regulation logic: It adopts a combination of "constant current fine-tuning + dynamic current sharing" to maintain the winding current at 1-2A (far lower than the constant torque stage), which greatly reduces the winding power consumption (more than 60% lower than the low-speed stable period of the constant torque stage); the dynamic current sharing algorithm runs continuously to ensure that the current deviation of each branch is ≤±0.3A (the accuracy is higher than that of the constant torque stage), avoiding magnetic circuit disturbances caused by local current anomalies during high-speed operation; at the same time, according to the speed change (the current is slightly reduced as the speed increases), the current and speed are adaptively matched to further reduce power consumption.

[0085] Magnetic circuit dominant logic: The "bias flux dominant + control flux fine-tuning" mode is adopted. The bias flux provided by the permanent magnet is increased to 70%-80%, and the control flux is reduced to 20%-30%. The core levitation force is maintained by the bias flux, and the control flux is only used to fine-tune the magnetic circuit deviation, reducing control current loss and improving the stability of the magnetic circuit (the sensitivity of the magnetic circuit to disturbances is reduced in the high-speed stage, and high-intensity control flux is not required).

[0086] Parameter settings: The displacement preset threshold is tightened (small fault tolerance range, adapted to the high-precision suspension requirements in the high-speed stage).

[0087] Auxiliary Control: The displacement-temperature co-sensing component focuses on enhancing temperature compensation while simultaneously monitoring winding and ambient temperatures. Due to the long-term high-speed operation of the flywheel in constant power mode, accumulated winding losses lead to a continuous temperature rise, significantly increasing the impact of temperature drift. This can easily cause displacement monitoring deviations and magnetic flux offsets. Therefore, a "real-time temperature acquisition + dynamic compensation" mechanism is adopted: winding and ambient temperatures are collected every 10ms, and a "displacement-temperature-magnetic circuit" linkage calibration algorithm is used to correct displacement errors caused by temperature drift in real time, improving compensation accuracy by 30% compared to constant torque mode. When the winding temperature rise is ≥10℃, not only is the winding current slightly reduced to decrease the temperature rise, but the temperature drift compensation is also increased simultaneously to ensure that the displacement monitoring accuracy remains within ±0.001mm, avoiding rotor offset caused by temperature drift and adapting to the requirements of long-term high-speed operation.

[0088] Figure 1 and Figure 2 This diagram presents a cross-sectional view of the PRMB and a schematic diagram of the shared winding connection, clearly demonstrating the core structure and winding arrangement logic of the PRMB. Both the left and right stators are four-tooth, two-pole structures, made of high-permeability silicon steel sheets to ensure magnetic circuit efficiency. A central axially magnetized annular permanent magnet provides bias flux for the entire magnetic bearing. The high-inertia flywheel rotor is located at the center of the PRMB, maintaining a 0.2mm levitation gap with the stator. The rotor surface is treated with anti-friction coating to prevent mechanical damage in case of levitation anomalies. The four sets of shared windings are made of high-conductivity copper wires, winding through the corresponding magnetic poles of the left and right stators respectively. This ensures that after current is applied, the core requirement of "reverse magnetic flux of corresponding left and right poles and same magnetic flux of opposite poles" is achieved, laying the structural foundation for star-connected control.

[0089] Figures 3 to 5 Focusing on the core structure of the star connection, one end of the four windings converges to form a common terminal, which is connected in series with a high-precision current shunt module to achieve precise current distribution and return current regulation. This ensures that the currents of the four windings are independent and do not interfere with each other, with current fluctuations controlled within ±2%. The other end of the shunt module is connected to the controller's common interface. The other end of the four windings serves as an independent control terminal (control terminals 1-4), which is connected to the controller's four independent control channels, forming an electrical structure of "common zero point + four independent branches." This enables independent and precise adjustment of each winding, providing structural support for dual-mode control.

[0090] Figure 6This demonstration showcases the complete logic flow of dual-mode control, adapting to all operating scenarios of large-inertia flywheels. The core adjustment is a dual-signal controller guided by "displacement + current." Through detection modules for speed, current, displacement, temperature, and vibration, the flywheel's operating status signals are collected in real time, and key data such as winding current, rotor suspension displacement, flywheel vibration, and winding temperature are fed back in real time, providing dual core support for control decisions (displacement signals determine suspension stability, and current signals determine winding operating status). Based on input and feedback signals, the controller automatically switches to constant torque mode (speed ≤ base speed) or constant power mode (speed > base speed) via a mode switching unit. The execution module drives the windings according to controller commands, cooperating with the flywheel drive unit to achieve flywheel start-up, stable operation, and shutdown. The protection module monitors the status of each component in real time, immediately triggering protection and alarms in case of abnormalities to ensure equipment safety.

[0091] Figure 7 This is a schematic diagram of the dual closed-loop control logic. The displacement-current dual closed-loop control adopts a collaborative logic of "outer closed loop (displacement control) as the main driver, inner closed loop (current control) as the support, and magnetic circuit compensation as the auxiliary driver". The core related logic is as follows: the outer closed loop (displacement control) determines the target value of current regulation (outputs the current regulation amount according to the displacement deviation), the inner closed loop (current control) realizes the precise regulation and balancing of current (tracks the current regulation amount of the outer closed loop and calibrates the current of each branch), and the magnetic circuit compensation module fine-tunes the current according to the displacement and temperature signals to further optimize the magnetic circuit state. Together, they form a complete closed loop of "displacement monitoring - deviation calculation - current regulation - magnetic circuit compensation - displacement feedback" to ensure control accuracy and stability.

[0092] Figure 8 This is a schematic diagram of the constant power mode control logic.

[0093] Constant power mode control (closed loop): Step 1: Mode Switching Confirmation - When the flywheel speed is continuously greater than or equal to the base speed, and the displacement fluctuation is less than or equal to 0.005mm and the winding current is stable below 2A, the controller mode switching judgment unit confirms that it has entered the constant power mode, and simultaneously issues a mode switching command, turns off the high-frequency displacement adjustment logic of the constant torque mode, and starts the constant power mode control program.

[0094] Step 2: Multi-parameter synchronous acquisition - The displacement-temperature co-sensing component synchronously acquires the rotor suspension displacement, winding temperature, and ambient temperature; the high-precision current shunt module acquires the current of each branch of the four windings and the total current; the speed sensor acquires the real-time speed, and all parameters are synchronously transmitted to the controller signal acquisition module for filtering and noise reduction (removing high-frequency interference signals).

[0095] Step 3: Parameter Threshold Judgment – ​​The single controller performs tiered judgment on the collected parameters to determine the adjustment direction, focusing on distinguishing scenarios where “displacement is appropriate but current is abnormal”: Displacement judgment: If the displacement is greater than 0.005mm (preset threshold), the rotor shifts in a certain direction, triggering the current fine-tuning priority, and fine-tuning the current of the corresponding magnetic pole winding. By controlling the small changes in magnetic flux, the rotor is pushed back to the center position to avoid magnetic circuit impact caused by sudden current changes. If the displacement is less than or equal to 0.005mm (levitational stability), the current base value is maintained, and the focus is on magnetic circuit optimization while judging the current status.

[0096] Current Judgment: For scenarios where "displacement ≤ 0.005mm (stable levitation)," three abnormal situations are subdivided and adjustment directions are clarified: ① Current deviation of each branch > ±0.3A (large current deviation): Dynamic current sharing fine-tuning is initiated. The core is "differentiated fine-tuning + synchronous displacement monitoring." The total current is not changed, only the current distribution of each branch is adjusted to avoid affecting levitation; ② Total current > 2A (total current too high): The current reduction command is triggered. "Slow fine-tuning + magnetic circuit compensation" is used to slightly reduce the total current. At the same time, the levitation force is maintained through magnetic circuit optimization to ensure that the displacement does not deviate from the threshold; ③ Total current < 1A (total current too low): The current is appropriately increased to slightly increase the total current to the standard range to avoid insufficient levitation force leading to subsequent displacement deviation.

[0097] Temperature judgment: If the winding temperature rise is ≥5℃, temperature compensation and current fine adjustment are activated simultaneously; if the winding temperature rise is ≥10℃, the current is reduced by 0.1-0.2A first, and then temperature compensation is strengthened.

[0098] Step 4: Precise current fine-tuning execution – Based on the parameter judgment results, the dual-mode control unit of the controller outputs precise current adjustment commands, and performs differentiated fine-tuning of the four windings through an independent control interface.

[0099] Step 5: Adaptive optimization of magnetic circuit - Combining the current fine-tuning results with displacement and temperature parameters, the single controller starts the adaptive optimization algorithm of magnetic circuit to dynamically adjust the magnetic circuit matching state, focusing on the adjustment of "appropriate displacement but abnormal current".

[0100] Magnetic flux distribution optimization: The ratio of bias flux to control flux is calculated in real time to ensure that the ratio of bias flux is stable at 70%-80% and the ratio of control flux is maintained at 20%-30%. When flux fluctuations (deviation > 5%) are detected, the magnetic flux distribution is corrected by fine-tuning the control current to avoid a decrease in magnetic circuit stiffness. Especially when the total current is adjusted, the magnetic flux distribution optimization compensates for the levitation force to ensure displacement stability.

[0101] Magnetic circuit loss optimization: Based on the changes in winding temperature, the current regulation frequency is adaptively adjusted (the regulation frequency is appropriately reduced when the temperature rises to avoid additional losses), and the winding heat dissipation structure is linked to reduce steady-state temperature rise, further reducing magnetic circuit losses.

[0102] Step 6: Temperature Compensation Linkage – This is performed in sync with magnetic circuit optimization and current fine-tuning. Through the “displacement-temperature-magnetic circuit” linkage calibration algorithm, the displacement error caused by temperature drift is corrected every 10ms.

[0103] Temperature drift correction: Based on the difference between the winding temperature and the ambient temperature, the displacement deviation compensation is calculated, and the displacement monitoring data is corrected in real time to ensure that the displacement monitoring accuracy is maintained within ±0.001mm.

[0104] Compensation strength adjustment: The higher the winding temperature rise, the greater the compensation strength (when the temperature rise is ≥10℃, the compensation accuracy is improved by 30% compared with the basic state), to avoid magnetic circuit deviation and rotor displacement caused by temperature drift.

[0105] Step 7: Steady-state judgment and feedback - The controller performs secondary acquisition and judgment on the adjusted parameters to form closed-loop control.

[0106] 1. Simplify the control structure, reduce costs, and improve adaptability: The design adopts a single controller integrated control + 4 sets of winding star connection design. The star connection + dynamic current sharing algorithm ensures that the current of each winding is balanced (deviation ≤ ±0.5A), avoids winding overload, and adapts to the suspension control requirements of large inertia flywheels across the entire speed range.

[0107] 2. Improved control accuracy and disturbance rejection capability: The design adopts displacement-temperature collaborative sensing + magnetic circuit flux calculation, which improves displacement monitoring accuracy. Combined with the optimized temperature compensation strategy under operating conditions, a simple compensation is used during the constant torque start-up stage due to low temperature and small temperature drift, focusing on suppressing displacement fluctuations. During the constant power long-term operation stage, due to rising temperature and large temperature drift, high-precision real-time dynamic compensation is used, which reduces the error after temperature drift compensation. The displacement-current dual closed-loop collaborative control, combined with magnetic circuit dynamic compensation, improves the magnetic circuit stiffness, which can quickly suppress rotor displacement fluctuations and significantly enhance disturbance rejection capability, solving the problems of suspension instability at low speed and the impact of temperature drift on accuracy at high speed.

[0108] 3. Strong adaptability, smooth switching, and significantly improved energy efficiency: The dual-mode control strategy is precisely adapted to the constant torque and constant power operating stages of the stator motor, ensuring suspension stability in the low-speed stage and reducing winding power consumption in the high-speed stage; the adaptive mode switching + current smooth transition mechanism minimizes switching impact, avoids rotor offset faults, and achieves stable control throughout the entire process.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A large inertia flywheel PRMB star-shaped connection structure, characterized in that, include: The system comprises multiple stators, multiple windings, multiple operating status detection components, a current shunt module, a controller, a permanent magnet, and a high-inertia flywheel rotor. The multiple windings are respectively wound on the multiple stators. The multiple operating status detection components are respectively integrated at the ends of the multiple stators. One end of the multiple windings and the multiple operating status detection components are respectively electrically connected to the controller. The other end of the multiple windings is electrically connected to the controller through the current shunt module. The permanent magnet and the high-inertia flywheel rotor are located between the multiple stators.

2. The large inertia flywheel PRMB star connection structure according to claim 1, characterized in that, The stators are symmetrical to each other, and each stator has a four-tooth, two-pole structure. The stator is a high-permeability silicon steel sheet laminate structure. The permanent magnet is located between the stators on the same side of the large-inertia flywheel rotor. There is a gap between the large-inertia flywheel rotor and the stator. The windings pass through the magnetic poles of the stators respectively. The controller is provided with a common interface and multiple independent interfaces. One end of each winding is electrically connected to the multiple independent interfaces, and the other end of each winding is electrically connected to the common interface through the current shunt module.

3. The large inertia flywheel PRMB star-shaped connection structure according to claim 1, characterized in that, The operating status detection component includes: a displacement sensor and a temperature sensing unit. The displacement sensor is embedded at the end of the stator, and the temperature sensing unit is built into the displacement sensor. A speed sensor and a vibration sensor are provided at the end of the stator. The displacement sensor, the temperature sensing unit, the speed sensor, and the vibration sensor are all electrically connected to the controller. The current shunt module integrates a current sensor and an alarm unit, both of which are electrically connected to the controller. The controller has a built-in signal acquisition module, a mode switching judgment module, a dual-mode control module, a protection module, and a fault diagnosis module.

4. A dual-mode control method for a large inertia flywheel, characterized in that, Based on the large inertia flywheel PRMB star-shaped connection structure according to any one of claims 1 to 3, the large inertia flywheel dual-mode control method includes: S1. The operating status of the large inertia flywheel is detected by multiple operating status detection components; S2. The controller switches between constant torque mode and constant power mode according to the operating state of the large inertia flywheel. S3. When switching to constant torque mode, control is performed through dual closed-loop control logic; S4. When switching to constant power mode, control is performed through constant power mode control logic.

5. The dual-mode control method for a large inertia flywheel according to claim 4, characterized in that, Step S1 includes: acquiring winding current signal through current shunt module, acquiring rotor suspension displacement signal through displacement sensor, acquiring rotor speed signal through speed sensor, acquiring flywheel vibration signal through vibration sensor, and acquiring winding temperature signal through temperature sensor; Step S2 includes: the controller automatically determines whether to switch to constant torque mode or constant power mode based on the winding current signal, the rotor suspension displacement signal, the rotor speed signal, the flywheel vibration signal and the winding temperature signal through the mode switching judgment module; and monitors the status of each link through the protection module, triggering protection and alarm when abnormality occurs; Step S3 includes: driving the winding to work through the constant torque mode control unit, and cooperating with the flywheel drive unit to realize the start-up, stable operation and shutdown of the flywheel; or, driving the winding to work through the constant power mode control unit, and cooperating with the flywheel drive unit to realize the start-up, stable operation and shutdown of the flywheel.

6. The dual-mode control method for a large inertia flywheel according to claim 4, characterized in that, Step S3 includes: S31, acquiring rotor displacement signal through displacement sensor, and correcting displacement deviation of rotor displacement signal through temperature compensation module; S32. The controller determines whether the actual displacement exceeds the preset threshold. S33. When the actual displacement exceeds the preset threshold, the suspension becomes unstable, and the inner current loop adjustment is activated. S34. Output the corresponding current adjustment amount according to the displacement deviation; S35. Collect and process current data; S36. Determine whether the current exceeds the preset range and deviation; S37. When the current exceeds the preset range and deviation, adjust the winding drive voltage; S38, Dynamic current sharing, fine-tuning of current; S39. Perform magnetic circuit compensation based on displacement and temperature until the rotor is stably suspended.

7. The dual-mode control method for a large inertia flywheel according to claim 6, characterized in that, After step S32, when the actual displacement does not exceed the preset threshold, the system is stably suspended, the current winding current is maintained, and step S35 is executed. Step S36 is followed by: when the current does not exceed the preset range and deviation, step S39 is executed.

8. The dual-mode control method for a large inertia flywheel according to claim 4, characterized in that, Step S4 includes: S41, constant power mode confirmation; S42, Multi-parameter synchronous acquisition and processing; S43, Parameter threshold determination; S44, precise current fine-tuning execution; S45, Adaptive optimization of magnetic circuit; S46, Temperature Compensation Linkage; S47. Steady-state judgment and feedback.

9. A dual-mode control method for a large inertia flywheel according to claim 8, characterized in that, Step S41 includes: when the flywheel speed is not less than the base speed, the displacement fluctuation is not greater than the preset displacement fluctuation, and the winding current is stable below the preset winding current, the controller's mode switching judgment unit confirms that it has entered the constant power mode, synchronously issues a mode switching command, closes the high-frequency displacement adjustment logic of the constant torque mode, and starts the constant power mode control program. Step S42 includes: the displacement sensor and temperature sensing unit collect the rotor suspension displacement, winding temperature and ambient temperature; the current shunt module collects the current of each branch of the four windings and the total current; the speed sensor collects the real-time speed, and all parameters are synchronously transmitted to the signal acquisition module of the controller for filtering and noise reduction to eliminate high-frequency interference signals. Step S43 includes: S431, determining whether the displacement exceeds a preset displacement threshold; S432. When the displacement does not exceed the preset displacement threshold, the suspension is stable. S433, Simultaneously perform current and temperature judgments; S434. When the total current is too small or too large, the total current is finely adjusted to maintain the levitation force; when the temperature rise is greater than the first preset temperature rise, the temperature compensation and current fine-tuning linkage are activated simultaneously. Step S44 includes: based on the parameter judgment result, the dual-mode control unit of the controller outputs a precise current adjustment command, and performs differentiated fine-tuning of the four windings through an independent control interface; Step S45 includes: S451, calculating the ratio of bias flux to control flux in real time, ensuring that the ratio of bias flux is stable within the first preset ratio range and the ratio of control flux is maintained within the second preset ratio range. When flux fluctuation is detected to be no less than the preset deviation, the flux distribution is corrected by fine-tuning the control current to avoid a decrease in magnetic circuit stiffness. S452. Based on the change in winding temperature, the current regulation frequency is adaptively adjusted, and the winding heat dissipation structure is linked to reduce steady-state temperature rise and further reduce magnetic circuit loss. Step S46 includes: performing synchronously with magnetic circuit optimization and current fine-tuning, and correcting the displacement error caused by temperature drift once every preset time through displacement, temperature and magnetic circuit linkage calibration algorithm; Step S47 includes: the controller performs secondary acquisition and judgment on the adjusted parameters to form closed-loop control.

10. A dual-mode control method for a large inertia flywheel according to claim 9, characterized in that, In step S41, the preset displacement fluctuation is 0.005mm and the preset winding current is 2A; Step S431 includes: when the displacement exceeds the preset displacement threshold, the rotor deflects, triggers the current fine-tuning priority, fine-tunes the current of the corresponding magnetic pole winding, and pushes the rotor back to the center position by controlling the small change in magnetic flux to avoid magnetic circuit impact caused by sudden current change. In step S432, the preset displacement threshold is 0.005 mm; Step S434 includes: for scenarios where the displacement is ≤0.005mm; when the current deviation of each branch is >±0.3A, start dynamic current sharing fine adjustment, without changing the total current, only adjust the current distribution of each branch to avoid affecting the suspension; When the total current is greater than 2A, a current reduction command is triggered to slightly reduce the total current. At the same time, the levitation force is maintained through magnetic circuit optimization to ensure that the displacement does not deviate from the threshold. When the total current is less than 1A, the current should be adjusted upwards appropriately to slightly increase the total current to the standard range, so as to avoid insufficient levitation force leading to subsequent displacement deviation. If the winding temperature rise is ≥5℃, temperature compensation and current fine-tuning linkage will be activated simultaneously. If the winding temperature rise is ≥10℃, the current should be reduced by 0.1-0.2A first, and then the temperature compensation should be strengthened. In step S451, the first preset percentage range is 70%-80%, the second preset percentage range is 20%-30%, and the preset deviation is 5%. In step S46, the preset time is 10ms; Step S46 includes: Temperature drift correction: Calculate the displacement deviation compensation amount based on the difference between the winding temperature and the ambient temperature, correct the displacement monitoring data in real time, and ensure that the displacement monitoring accuracy is maintained within ±0.001mm; Compensation strength adjustment: The higher the winding temperature rise, the greater the compensation strength, to avoid magnetic circuit deviation and rotor displacement caused by temperature drift.

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