Four-step motor double-wire parallel-wound pure magnetic field commutation non-magnetic DC motor

Abstract

The application relates to a four-step motor double-wire parallel-wound pure magnetic field commutation non-magnetic direct-current motor, which comprises a ring-shaped solid magnetic conduction magnetic circuit structure of a stator; a rotor is coaxially arranged in the stator and is a ring-shaped magnetic conduction structure; each magnetic pole position of the rotor is provided with a double-wire parallel-wound structure; the double-wire parallel-wound structure comprises a first winding and a second winding which are arranged in the same slot and have independent electric circuits; a rectification and filtering assembly is fixedly arranged on the rotor and rotates synchronously with the rotor, the rectification and filtering assembly comprises a rectification bridge and a filtering capacitor, and the alternating current input end of the rectification bridge is connected with the leading-out end of the second winding; the output end of a time sequence control module is connected with the leading-out end of the first winding, and the time sequence control module has an output configuration for cyclically outputting on-off control signals from one to four steps. The technology does not need a permanent magnet to magnetize a field, does not need to switch current directions, and does not need frequency conversion equipment to control, relies on double-wire winding to divide and excite a magnetic field, a circuit to rectify and lock a magnetic pole, and four-step time sequence to switch a magnetic field phase, and realizes pure direct-current stable driving operation.

Description

Technical Field

[0001] This application belongs to the field of motor technology, and in particular relates to a four-step motor with dual-wire parallel winding, pure magnetic field commutation, and no frequency conversion or magnetic DC motor. Background Technology

[0002] Currently, mainstream DC motors, brushless motors, and excitation motors on the market face several insurmountable technical bottlenecks, significantly limiting the industry's development.

[0003] Traditional permanent magnet DC motors rely on permanent magnets to provide a fixed magnetic field. During operation, they require frequent switching of the coil current direction to change the electromagnetic polarity and drive the rotor to rotate. These motors are highly dependent on rare-earth permanent magnet materials, which not only result in high raw material costs but also lead to demagnetization failure under high temperature and vibration conditions, thus limiting the equipment's lifespan. At the same time, the current commutation process generates electric sparks, back electromotive force, and electromagnetic harmonics, resulting in high operating losses, severe heat generation, and difficulty in further improving the motor's efficiency.

[0004] Conventional non-magnetic excitation motors generally follow the operating rule that commutation inevitably leads to current commutation. To adjust the angle of the electromagnetic force and drive the rotor to rotate continuously, the direction of current flow inside the windings must be changed. Frequent current commutation can cause current surges, resulting in motor stalling and torque fluctuations. Furthermore, the equipment must be equipped with complex electrical control components such as frequency converters and inverters, leading to a high failure rate in the control system and weak power output under heavy load conditions, making it difficult to meet the needs of high-power industrial applications.

[0005] Currently, the dual-wire parallel winding structure is only used in conventional designs such as parallel current boosting, series voltage boosting, and symmetrical current commutation. There is no related technical solution that can achieve the following: using the rotor dual-wire parallel winding structure, one set of wires completes the excitation coupling power extraction, and the other set of wires generates the rotor DC magnetic poles through rectification and filtering. At the same time, it combines four-step timing to complete pure magnetic field commutation, without current commutation throughout the process, and eliminates the design concept of a non-magnetic DC motor that eliminates frequency conversion drive.

[0006] In summary, magnetless motors generally rely on frequency conversion and commutation structures, resulting in complex drive mechanisms; they cannot generate stable magnetic poles independently, making them prone to step loss and vibration during operation; mainstream motors rely on current commutation to achieve rotation, and there is no architecture that can drive operation simply by switching the phase of the magnetic field; there is a lack of truly permanent magnet-free, frequency-free, commutation-loss-free, and stable self-sustaining industrial-grade magnetless DC motors on the market.

[0007] The foregoing statements are for informational purposes only and are not intended to provide background information in connection with this application. Unless otherwise stated herein, the content described in this section is not prior art to the rest of this application. Summary of the Invention

[0008] This invention proposes a four-step motor with dual-wire parallel winding and pure magnetic field commutation, a non-magnetic DC motor. The invention aims to eliminate the permanent magnet structure, eliminate the frequency converter and current commutation components, and provide a novel non-magnetic DC motor based on the four-step motor principle, using a rotor dual-wire parallel winding architecture, relying on its own excitation rectification to form fixed magnetic poles, and achieving drive only through magnetic field phase switching, maintaining constant DC directional current throughout the entire process.

[0009] The core technological breakthrough of this application is that this technology does not require a permanent magnet to maintain the magnetic field, does not require switching the current direction, and does not require frequency conversion equipment for regulation. It can achieve stable pure DC drive operation by relying solely on the dual-wire winding for independent excitation, circuit rectification to lock the magnetic poles, and four-step timing to switch the magnetic field phase.

[0010] To achieve the above objectives, the present invention provides the following technical solution: A four-step, dual-wire, parallel-wound, pure magnetic field commutated, non-magnetic DC motor includes: The stator is a ring-shaped solid magnetic circuit structure; The rotor is coaxially disposed inside the stator. The rotor has an annular magnetic conductive structure. Each magnetic pole position of the rotor is provided with a double-wire parallel winding structure. The double-wire parallel winding structure includes a first winding and a second winding. The first winding and the second winding are arranged in the same slot and their electrical circuits are independent of each other. A rectifier and filter assembly is fixedly mounted on the rotor and rotates synchronously with the rotor. The rectifier and filter assembly includes a rectifier bridge and a filter capacitor. The AC input terminal of the rectifier bridge is connected to the lead-out terminal of the second winding. A timing control module, the output of which is connected to the lead-out end of the first winding; the timing control module has an output configuration that cyclically outputs on / off control signals according to the first to fourth steps. The first step is to energize the first winding to generate a dynamic magnetic field coupled with the fixed N-S magnetic poles formed by the second winding after rectification and filtering. The second step is to switch the angle of the excitation magnetic field generated by the first winding to cause the composite magnetic field to undergo circumferential displacement. The third step is to reset the magnetic circuit state; The fourth step is to return to the first step and repeat the process.

[0011] Furthermore, the annular solid magnetic circuit structure of the stator is made of soft magnetic material, the inner peripheral wall of the stator is a smooth and continuous slotless magnetic circuit bearing surface, and the interior of the stator is a solid filling structure.

[0012] Furthermore, the soft magnetic material is a silicon steel sheet, an amorphous alloy, or a soft magnetic composite material.

[0013] Furthermore, the rectifier filter assembly also includes a freewheeling element, which is connected in parallel with the filter capacitor; when the first winding switches the excitation magnetic field angle in the second step, the freewheeling element provides a freewheeling path for the second winding to maintain the magnetic flux continuity of the fixed NS poles.

[0014] Furthermore, the timing control module includes a timing logic circuit and a power drive circuit. The timing logic circuit generates cyclic timing signals for the first to fourth steps, and the power drive circuit controls the on / off state of the first winding according to the cyclic timing signals.

[0015] Furthermore, the timing control module is provided with a rotor position signal input terminal, and the timing control module dynamically adjusts the duration of any one of the first to fourth steps according to the rotor position detection signal received by the rotor position signal input terminal.

[0016] Furthermore, the rotor position detection signal is provided by a Hall sensor, photoelectric encoder, or rotary transformer.

[0017] Furthermore, the timing control module has a current / voltage signal sampling terminal. The timing control module detects the current signal and / or voltage signal of the first winding or the second winding through the current / voltage signal sampling terminal to calculate the rotor position, and dynamically adjusts the output timing of the first to fourth steps according to the calculated rotor position.

[0018] Furthermore, in the dual-wire parallel winding structure, the wire diameter and number of turns of the first winding and the second winding are determined according to the rated power of the motor, and the winding direction of the first winding and the second winding are consistent.

[0019] A driving method for a four-step pure magnetic field commutated non-magnetic DC motor, employing the aforementioned motor structure, includes the following steps: The timing control module cyclically outputs on / off control signals to the first winding in steps one through four. The second winding converts the induced alternating current into unidirectional constant direct current through the rectifier and filter assembly, forming a fixed N-S magnetic pole array at each magnetic pole position of the rotor; The first winding sequentially generates a coupled magnetic field, switches the excitation magnetic field angle to cause circumferential displacement of the composite magnetic field, and resets the magnetic circuit state according to the on / off control signal. Repeat the above steps to drive the rotor to rotate continuously.

[0020] The present invention has the following advantages: 1) A completely new motor operation system has been constructed. This application proposes a systematic technical solution of "rotor dual-wire parallel winding, self-excitation power extraction, self-rectification and pole setting, and four-step pure magnetic field commutation". Specifically: the first winding, as the excitation coupling winding, draws power from the outside to generate a dynamic magnetic field; the second winding obtains alternating electrical energy from the first winding through electromagnetic induction, which is then converted into direct current by a rectifier and filter component that rotates with the rotor, and autonomously generates constant N and S magnetic poles; the timing control module only switches the spatial phase of the excitation magnetic field according to the four-step timing sequence, which can drive the rotor to rotate continuously. The above-mentioned multiple technical features are not simply functional superpositions, but form a closed-loop synergistic system of "power extraction-rectification-pole setting-phase adjustment" - the changing excitation magnetic field provided by the first winding is both the source of driving force and the excitation source for the second winding to draw power; the fixed magnetic pole formed by the second winding after rectification provides the first winding with the object of coupling; the four-step timing sequence is precisely matched with the magnetic pole arrangement and force angle of the rotor. The various elements are interdependent and mutually conditional, together forming a completely new underlying logic for motor drive, possessing independent core technological barriers, and not a simple combination of existing technological features.

[0021] 2) Completely eliminates the limitations of permanent magnet materials, thus eliminating the risk of demagnetization failure. This application completely eliminates permanent magnets; the rotor magnetic poles are generated by the unidirectional DC current rectified and applied to the second winding, making it an electromagnet. The strength of this magnetic field depends solely on the magnitude of the current applied to the second winding after rectification and filtering, and does not permanently decay with temperature, time, or vibration. Even under extreme high-temperature or high-impact conditions, as long as the rectifier and filter components function normally, the rotor magnetic poles can be stably maintained, significantly improving motor lifespan and reliability. Simultaneously, eliminating reliance on rare-earth materials greatly reduces raw material costs.

[0022] 3) The electronic control structure is extremely simple, and the system reliability is significantly improved.

[0023] Traditional brushless DC motors and permanent magnet synchronous motors must be equipped with frequency converters or inverters to convert DC power into three-phase AC power and generate sinusoidal or square wave drive current through complex pulse width modulation (PWM) strategies. Frequency converters contain a large number of power switching devices (such as IGBTs and MOSFETs), drive circuits, sampling circuits, and microcontrollers (MCUs) or digital signal processors (DSPs), resulting in high hardware costs, complex control systems, and long software development cycles. Furthermore, frequency converters generate switching losses, electromagnetic interference (EMI), and heat dissipation issues during switching, and the failure of any power device will cause the motor to stop.

[0024] This application requires only a single, extremely simple timing control module. The core of this module consists solely of a logic circuit that generates a four-step cyclic timing sequence (such as a 555 timer with a counter), and it does not include frequency converters, inverters, or high-frequency switching devices. It requires no microcontroller programming, no PWM modulation, and no complex software algorithms. The power drive section only needs to control the on / off state of the first winding, resulting in simple drive logic. The entire control system has extremely low hardware costs, eliminates the risk of software crashes or malfunctions, exhibits excellent electromagnetic interference resistance, and is particularly suitable for harsh industrial environments.

[0025] 4) No current commutation throughout the entire process, resulting in low operating losses and high energy efficiency.

[0026] All existing DC motors (including brushed and brushless DC motors) require switching the direction of current in the windings during operation to change the electromagnetic polarity and generate continuous torque in conjunction with the rotor magnetic poles. Brushed motors achieve commutation through mechanical commutators and brushes, which generates electrical sparks, wear, and back electromotive force spikes. Brushless motors achieve electronic commutation through frequency converters, which eliminates mechanical wear, but still experience switching losses and electromagnetic harmonics due to sudden current changes during commutation.

[0027] This application completely overturns the above model. From motor start-up to full-speed operation, the current direction in the first and second windings remains constant throughout, without any commutation operation. The generation of torque and continuous rotation rely entirely on a four-step time-sequential cycle to change the spatial phase of the excitation magnetic field, i.e., "circumferential displacement of the composite magnetic field". Due to the absence of abrupt changes in current direction: there are no back electromotive force spikes, eliminating the need for additional absorption circuits; there are no commutation sparks, improving explosion-proof safety; there are no switching losses and harmonic losses caused by current abrupt changes; and copper losses (I²R losses) are at their lowest steady-state level under constant current conditions.

[0028] Taking all the above factors into account, the energy conversion efficiency of this application is significantly better than that of traditional excitation motors and permanent magnet motors, and the heat generation of the motor body is greatly reduced, which can significantly save energy consumption.

[0029] 5) The combination of fixed magnetic poles and smooth phase switching results in excellent dynamic performance. Traditional non-magnetic excitation motors (such as series motors and shunt motors) suffer from poor magnetic pole stability due to the rotor magnetic field being generated by current, the direction of which fluctuates with changes in speed or load. This leads to issues like loss of synchronization, jitter, or torque fluctuations. In this application, the rotor's N and S magnetic poles are maintained by a constant DC current after rectification and filtering from the second winding. Once established, this current remains stable and does not change with fluctuations in rotor speed or load torque. This provides the motor with an extremely stable magnetic field reference. Furthermore, the four-step timing switch of the excitation magnetic field phase is a "flexible switch"—the magnetic field angle gradually shifts rather than abruptly, resulting in a continuous and smooth change in the composite magnetic field, avoiding mechanical shocks and torque pulsations caused by sudden magnetic field changes. Therefore, the motor of this application features sufficient starting torque, smooth low-speed operation, sensitive high-speed response, and strong overload resistance. These performance advantages make this motor particularly suitable for applications requiring stable power output and overload capacity, such as heavy-duty agricultural power, industrial constant-power transmission, and uninterrupted continuous operation.

[0030] 6) Flexible power supply options and wide applicability. This application adopts a pure DC power supply mode, which is not limited by AC frequency and phase number, and can be adapted to various DC power sources. Specifically, it can be connected to batteries (such as 24V / 48V / 72V lead-acid batteries or lithium battery packs), suitable for vehicle-mounted and mobile equipment; it can also be connected to DC power output after rectification and filtering of AC grid (such as 220V / 380V industrial power) by a rectifier bridge, suitable for stationary industrial equipment. The power supply voltage level is flexibly designed according to the rated power of the motor, without the need for additional frequency converters or power conversion modules, making it plug-and-play. The above power supply compatibility allows this motor to quickly adapt to various existing power supply environments without the need to modify the user-side power supply facilities, lowering the threshold for promotion and application. Attached Figure Description

[0031] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0032] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0033] Figure 1This is a schematic diagram of the structure of a four-step motor with dual-wire parallel winding and pure magnetic field commutation without magnetism, provided in an embodiment of the present invention. Figure 2 A schematic diagram of the rotor structure in a four-step, dual-wire, parallel-wound, pure magnetic field commutated, non-magnetic DC motor provided in an embodiment of the present invention; Figure 3 This is a circuit connection diagram of a four-step motor with dual-wire parallel winding and pure magnetic field commutation, provided for an embodiment of the present invention.

[0034] In the picture: 1. Stator; 2. Rotor; 21. First winding; 22. Second winding; 3. Rectifier and filter assembly; 31. Rectifier bridge; 32. Filter capacitor; 4. Timing control module; 41. Timing logic circuit; 42. Power drive circuit; 5. Signal trigger; 6. Fiber optic positioner. Detailed Implementation

[0035] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0036] like Figure 1 As shown, the present invention provides a four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor, comprising: Stator 1, wherein stator 1 is a ring-shaped solid magnetic circuit structure used for conducting and converging magnetic flux; Rotor 2 is coaxially disposed inside stator 1. Rotor 2 has a ring-shaped magnetic conductive structure. Each magnetic pole position of rotor 2 is provided with a double-wire parallel winding structure. The double-wire parallel winding structure includes a first winding 21 and a second winding 22. The first winding 21 and the second winding 22 are arranged in the same slot and their electrical circuits are independent of each other. The rectifier and filter assembly 3 is fixedly mounted on the rotor 2 and rotates synchronously with the rotor 2. The rectifier and filter assembly 3 includes a rectifier bridge 31 and a filter capacitor 32. The AC input terminal of the rectifier bridge 31 is connected to the lead-out terminal of the second winding 22. The timing control module 4 has its output terminal connected to the lead-out terminal of the first winding 21; the timing control module 4 has an output configuration that cyclically outputs on / off control signals according to the first to fourth steps.

[0037] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. The four-step motor, a dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor, specifically includes: Stator 1 is a ring-shaped solid magnetic circuit structure. Stator 1 has no windings or permanent magnets inside; it only serves as a carrier for magnetic flux conduction and magnetic field coupling. The inner peripheral wall of stator 1 is a smooth, continuous, slotless magnetic circuit bearing surface. The interior of stator 1 is a solid filled structure, without winding slots, magnet mounting slots, or coil cavities. In a preferred embodiment, stator 1 is formed by axially stacking silicon steel sheets, and the inner circular surface of stator 1 is insulated to reduce eddy current losses.

[0038] Preferably, the soft magnetic material is a silicon steel sheet, stacked axially with a stacking factor of not less than 0.95. Alternatively, the soft magnetic material can be an amorphous alloy, exhibiting lower iron loss characteristics and suitable for high-frequency operation. Another alternative is a soft magnetic composite material (SMC), formed by pressing insulated iron powder particles, suitable for complex three-dimensional magnetic circuit structures.

[0039] Rotor 2, coaxially disposed inside stator 1, wherein rotor 2 is a ring-shaped magnetically conductive structure. Figure 2 As shown, each magnetic pole position of rotor 2 is provided with a double-wire parallel winding structure, which includes a first winding 21 and a second winding 22. The first winding 21 and the second winding 22 are arranged in the same slot and their electrical circuits are independent of each other. The two wires are arranged in the same slot, and the number of turns and the winding direction of the windings are consistent. Rotor 2 is rotatably supported in the motor housing by a rotating shaft, and an air gap is provided between rotor 2 and stator 1.

[0040] The power adaptation of the winding parameters of rotor 2 includes the following: for low-power models (e.g., below 100W), fine-gauge enameled wire (e.g., AWG28-AWG32) is used, increasing the number of winding turns (50-80 turns per pole) to adapt to low-voltage DC power supply (e.g., 12V / 24V); for medium-power models (e.g., 1kW-10kW), medium-gauge enameled wire (e.g., AWG18-AWG22) is used, with a moderate number of winding turns (20-40 turns per pole), to adapt to medium-voltage DC power supply (e.g., 48V / 110V); for high-power models (e.g., above 10kW), thick-gauge enameled wire (e.g., AWG10-AWG16) is used to reduce line impedance to carry large currents, with fewer winding turns (10-20 turns per pole), to adapt to high-voltage DC power supply (e.g., rectified DC after 220V / 380V). The winding structure, functional division, and magnetic field commutation principle remain unchanged across different power levels.

[0041] Both the first winding 21 and the second winding 22 are concentrated windings that are continuously wound along each magnetic pole of the rotor 2. The concentrated windings on each magnetic pole have short end lengths, low copper losses, and good heat dissipation, making them suitable for high-speed operation scenarios.

[0042] A rectifier and filter assembly 3 is fixedly mounted on the rotor 2 and rotates synchronously with the rotor 2. The rectifier and filter assembly 3 includes a rectifier bridge 31 and a filter capacitor 32. The AC input terminal of the rectifier bridge 31 is connected to the lead-out terminal of the second winding 22. In a preferred embodiment, the rectifier bridge 31 is constructed using fast recovery diodes to form a full-wave rectifier bridge 31, and the filter capacitor 32 is a low-ESR electrolytic capacitor to ensure stable rectified output and low ripple.

[0043] In one extended embodiment, the rectifier filter assembly 3 further includes a freewheeling element connected in parallel with the filter capacitor 32. When the first winding 21 switches the excitation magnetic field angle in the second step, the freewheeling element provides a freewheeling path for the second winding 22, maintaining the magnetic flux continuity of the fixed NS poles. In a preferred embodiment, the freewheeling element is a Schottky diode, which has a short reverse recovery time and low forward voltage drop, effectively suppressing voltage spikes at the rectifier output and ensuring that the rotor 2NS poles do not experience magnetic flux interruption during excitation magnetic field switching.

[0044] The timing control module 4 is located outside the motor housing and is connected to the lead-out end of the first winding 21 of the rotor 2 via wires (conductive slip rings or flexible cables can be used). The timing control module 4 includes a timing logic circuit 4 and a power drive circuit 42. The timing logic circuit 4 generates a cyclic timing signal for the first to fourth steps, and the power drive circuit 42 controls the on / off state of the first winding 21 according to this timing signal. The power drive circuit 42 consists of four switching devices (such as MOSFETs or IGBTs), which control the energization and de-energization of each segment of the first winding 21 respectively.

[0045] The four timing steps in this technology are as follows: Step 1 (T1): Energize the first winding 21 to generate a dynamic magnetic field coupled with the fixed NS magnetic poles formed by the second winding 22 after rectification and filtering; Step 2 (T2): Switch the angle of the excitation magnetic field generated by the first winding 21 to cause the composite magnetic field to undergo circumferential displacement. Step 3 (T3): Reset the magnetic circuit state; Step 4 (T4): Return to step 1 and repeat.

[0046] The timing control module 4 is implemented in hardware. It includes a timing logic circuit 4 and a power drive circuit 42. The timing logic circuit 4 generates cyclic timing signals for steps one through four, and the power drive circuit 42 controls the on / off state of the first winding 21 based on these signals. The timing logic circuit 4 uses an NE555 timer circuit in conjunction with a CD4017 counter to form a cyclic timing generator, achieving a four-step timing cycle purely in hardware. This eliminates the need for a microcontroller or software programming, providing strong anti-interference capabilities, fast response speed, and no risk of software failure. The power drive circuit 42 uses MOSFET or IGBT switches in conjunction with an isolation drive circuit to achieve high-current on / off control of the first winding 21.

[0047] The lead-out end of the first winding 21 is connected to the timing control module 4, which controls its on / off state in four steps. The lead-out end of the second winding 22 is rectified by the rectifier bridge 31 and then connected to the filter capacitor 32 to output smooth DC power, forming a constant NS magnetic pole on the rotor 2 pole shoe.

[0048] To extend the technology for rotor 2 position detection, the timing control module 4 of this technology can feature closed-loop position feedback control. Specifically, the timing control module 4 is equipped with a rotor 2 position signal input terminal. Based on the rotor 2 position detection signal received from the rotor 2 position signal input terminal, the timing control module 4 dynamically adjusts the duration of any one of the first to fourth steps. The rotor 2 position detection signal is provided by a Hall sensor, photoelectric encoder, or rotary transformer. Based on the real-time rotor 2 position, the timing control module 4 advances or delays the switching of the excitation magnetic field angle, ensuring that the composite magnetic field always maintains the optimal matching angle with the rotor 2 position, thereby improving the motor's load-carrying capacity and operational stability.

[0049] Alternatively, the timing control module 4 employs sensorless control. The timing control module 4 has a current / voltage signal sampling terminal. It detects the current and / or voltage signals of the first winding 21 or the second winding 22 through the current / voltage signal sampling terminal to calculate the position of the rotor 2, and dynamically adjusts the output timing of steps one through four based on the calculated rotor 2 position. This sensorless control scheme eliminates physical position sensors, reducing system cost and potential failure points, and is suitable for harsh environments such as high temperature, high humidity, and strong vibration.

[0050] It is important to note that regardless of whether closed-loop position feedback control, sensorless control, or other more advanced control algorithms (such as vector control (FOC) or direct torque control (DTC)) are used, the final execution layer must return to the magnetic field phase cyclic switching logic of steps one through four mentioned above. This four-step timing sequence is the physical basis for the continuous rotation of rotor 2, and no control strategy can operate independently without bypassing this underlying timing sequence.

[0051] The working principle of this embodiment is as follows: After the motor is connected to a DC power supply, the timing control module 4 outputs on / off control signals to the first winding 21 in a four-step timing cycle. When the first winding 21 is energized, the changing magnetic field it generates induces an alternating electromotive force in the second winding 22 through electromagnetic induction (mutual inductance effect). The second winding 22 converts the induced AC current into unidirectional constant DC current through the rectifier and filter component 3, autonomously generating a fixed NS magnetic pole array at each magnetic pole position of the rotor 2, establishing the magnetic field reference of the rotor 2. At the same time, according to the control signals of the timing control module 4, the first winding 21 sequentially generates a dynamic magnetic field coupled with the fixed NS magnetic poles, switches the excitation magnetic field angle to cause circumferential displacement of the composite magnetic field, and resets the magnetic circuit state. During the four-step timing cycle execution, the spatial position of the composite magnetic field continuously undergoes circumferential displacement, driving the rotor 2 to rotate continuously. Throughout the entire operation, the current direction of all windings remains constant, without any commutation operation, and without relying on the frequency converter or inverter to adjust the current frequency, realizing the operation of a pure DC direct-drive magnetless motor.

[0052] In terms of specific structure, the stator 1 winding assembly adopts a double-wire parallel winding method to form two sets of electrically independent winding structures, with a total of 8 terminals. The first set of independent windings has A-phase head (terminal 1) and A-phase tail (terminal 3) as terminals, while the second set has B-phase head (terminal 2) and B-phase tail (terminal 4) as terminals. A-phase head connects to IGBT1, and A-phase tail connects to IGBT3; B-phase head connects to IGBT2, and B-phase tail connects to IGBT4. The output terminals of all four IGBT devices are connected to the negative terminal of the power supply. The remaining 4 terminals of the two windings—the center taps of the first and second windings—are each connected in series with a diode and then connected to the positive terminal of the power supply. The positive terminal of each diode is connected to the winding tap, and the negative terminal is connected to the positive terminal of the power supply, forming a unidirectional conduction path. This ensures that the winding current always flows from the positive terminal of the power supply through the winding to the IGBT, avoiding reverse current surges.

[0053] During operation, the four IGBTs cycle on and off according to a fixed timing sequence: Step 1: IGBT1 is turned on, and the A-phase terminal is energized. The current path is: positive terminal of power supply → diode → first winding → A-phase terminal → IGBT1 → ground. The first winding terminal is energized. Step 2: IGBT2 is turned on, the B-phase terminal is energized, and the current path is: positive terminal of power supply → diode → second winding → B-phase terminal → IGBT2 → ground. The second winding terminal is energized. Step 3: IGBT3 is turned on, while IGBT1 is turned off. The tail of phase A is energized. The current path is: positive terminal of power supply → diode → first winding → tail of phase A → IGBT3 → ground. The tail of the first winding is energized and the head is de-energized. Step 4: IGBT4 is turned on, while IGBT2 is turned off. The tail of phase B is energized. The current path is: positive terminal of power supply → diode → second winding → tail of phase B → IGBT4 → ground. The tail of the second winding is energized and the head is de-energized.

[0054] By executing the above four steps in a cyclical manner, a commutation-without-commutation working mode is achieved, in which the magnetic field continuously commutates while the direction of the current flowing through each winding remains unchanged.

[0055] The difference between this invention and existing technologies lies in the following: Existing technologies typically employ a three-phase star or delta connection for the stator winding, using a frequency converter to control the phase and amplitude of the three-phase current to generate a rotating magnetic field. In contrast, the stator winding of this invention is a two-phase independent structure, with each winding selectively energized at its head or tail end via a single IGBT switch. The current direction is constant, eliminating the need for frequency converter modulation and simplifying the control logic. These distinguishing technical features result in the following advantages: elimination of switching losses and harmonic interference introduced by the frequency converter; reduced hardware costs and software complexity of the control system; realization of a low-loss operation mode of "commutation without current conversion"; and the coordinated operation of the four-step timing sequence and the self-rectifying and polarization function of the rotor 2 dual-wire winding, enabling the motor to obtain continuous and stable rotational driving force without permanent magnets.

[0056] like Figure 3 As shown, in some embodiments of the present invention, the stator 1 may be provided with an excitation winding. The stator 1 winding assembly adopts a double-wire parallel winding method to form two sets of electrically independent winding structures, namely the A-phase winding and the B-phase winding. Eight terminals are led out as a whole, wherein the A-phase winding is provided with an A-phase head (terminal 1) and an A-phase tail (terminal 3), and the B-phase winding is provided with a B-phase head (terminal 2) and a B-phase tail (terminal 4). The A-phase head is connected to IGBT1, and the A-phase tail is connected to IGBT3; the B-phase head is connected to IGBT2, and the B-phase tail is connected to IGBT4; the output terminals of the four IGBT devices are connected to the negative terminal of the power supply. The remaining four terminals of the A-phase winding and the B-phase winding—that is, the center taps of each winding—are each connected in series with a diode and then connected to the positive terminal of the power supply. The positive terminal of each diode is connected to the winding tap terminal, and the negative terminal is connected to the positive terminal of the power supply, forming a unidirectional conduction path to ensure that the winding current always flows from the positive terminal of the power supply through the winding to the IGBT, avoiding reverse current surges. The rotor 2 still adopts a double-wire parallel winding structure. The first winding 21 is an excitation coupling winding, and the second winding 22 is connected to the rectifier and filter component 3 fixed on the rotor 2, forming a constant NS magnetic pole independently.

[0057] During operation, the four IGBTs cycle on and off according to a fixed timing sequence: The first step is to turn on IGBT1, energize the A-phase connector, and the current path is: positive terminal of power supply → diode → A-phase winding → A-phase connector → IGBT1 → ground; The second step is to turn on IGBT2, energize the B phase connector, and the current path is: positive power supply → diode → B phase winding → B phase connector → IGBT2 → ground. The third step is to turn on IGBT3 and turn off IGBT1 at the same time. The tail of phase A is energized, and the current path is: positive terminal of power supply → diode → phase A winding → tail of phase A → IGBT3 → ground. The head of phase A is de-energized. In the fourth step, IGBT4 is turned on while IGBT2 is turned off, and the tail of phase B is energized. The current path is: positive terminal of power supply → diode → phase B winding → tail of phase B → IGBT4 → ground, and the head of phase B is de-energized.

[0058] The above four-step timing sequence is executed cyclically to achieve a commutation-without-commutation working mode in which the magnetic field continuously commutates while the direction of the current flowing through each winding remains unchanged. The four-step timing switching of the stator 1 excitation winding generates a dynamic rotating magnetic field. This dynamic magnetic field is coupled with the constant NS magnetic poles generated by the self-rectified stator of the rotor 2 double-wire winding, and they work together to achieve stable rotation drive while eliminating the permanent magnet and the frequency converter.

[0059] The difference between this invention and existing technologies lies in the following: Existing technologies typically employ a three-phase star or delta connection for the stator winding, using a frequency converter to control the phase and amplitude of the three-phase current to generate a rotating magnetic field. In contrast, the stator winding of this invention is a two-phase independent structure, with each winding selectively energized at its head or tail end via a single IGBT switch. The current direction is constant, eliminating the need for frequency converter modulation and simplifying the control logic. These distinguishing technical features result in the following advantages: elimination of switching losses and harmonic interference introduced by the frequency converter; reduced hardware costs and software complexity of the control system; realization of a low-loss operation mode of "commutation without current conversion"; and the coordinated operation of the four-step timing sequence and the self-rectifying and polarization function of the rotor 2 dual-wire winding, enabling the motor to obtain continuous and stable rotational driving force without permanent magnets.

[0060] The circuit connection relationship of the four-terminal lead-out structure of the above stator 1 excitation winding and the commutation-free control method is shown in the table below:

[0061] Common terminal (remaining 4 terminals): Connect a diode in series to each terminal and then connect them to the positive power supply.

[0062] It should be noted that the above-mentioned four-terminal lead-out structure and four-step timing control scheme of stator 1 can be used as an optional implementation scheme of stator 1 structure in this invention, working in conjunction with the dual-wire self-rectifying stator structure of rotor 2 of this invention; this implementation scheme also falls within the protection scope of this application. Both the stator 1 without windings (i.e., stator 1 is only a ring-shaped solid magnetic circuit structure) and the stator 1 with windings (i.e., the above-mentioned four-terminal lead-out structure) can realize the core inventive concept of this invention, and neither departs from the protection scope of this application.

[0063] After the motor is connected to an external DC power source (which can be DC power from a battery or rectified DC power), the power is distributed by the power supply module. The power supply module includes a step-down unit (such as a DC-DC converter) to convert the input high-voltage DC power into the operating voltage required by the timing control module 4 and the first winding 21. The step-down unit has overvoltage, overcurrent, and short-circuit protection functions to ensure stable operation of the control system.

[0064] In applications requiring higher control precision, the timing control module 4300 can be configured with a rotor 2 position signal input terminal to receive rotor 2 position detection signals. For example... Figure 2 As shown, the rotor 2 position detection device can be a Hall sensor, a photoelectric encoder, or a fiber optic positioner 6. When the fiber optic positioner 6 is used, the fiber optic positioner 6 is fixedly installed on the stator 1 side of the motor. It is used to detect the trigger signal generated by the signal trigger 5 (such as a metal protrusion or reflective mark) set in the circumferential direction of the rotor 2 as the rotor 2 rotates. It is connected to the photoelectric module through the optical fiber. The photoelectric module converts the light pulse signal into an electrical signal and sends it to the timing control module 4300. The timing control module 4300 dynamically adjusts the duration of the first to fourth steps according to the real-time rotor 2 position.

[0065] It should be noted that the aforementioned fiber optic positioner 6 and photoelectric module are optional enhancements of this invention, rather than essential technical features. In the basic embodiment of this invention, the timing control module 4300 operates in a fixed four-step timing cycle, driving the motor to rotate stably without any rotor 2 position detection device.

[0066] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the systems, devices, apparatuses, modules or units described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0067] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application 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 of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A four-step, dual-wire, parallel-wound, pure magnetic field commutated, non-magnetic DC motor, characterized in that, include: The stator is a ring-shaped solid magnetic circuit structure; The rotor is coaxially disposed inside the stator. The rotor has an annular magnetic conductive structure. Each magnetic pole position of the rotor is provided with a double-wire parallel winding structure. The double-wire parallel winding structure includes a first winding and a second winding. The first winding and the second winding are arranged in the same slot and their electrical circuits are independent of each other. A rectifier and filter assembly is fixedly mounted on the rotor and rotates synchronously with the rotor. The rectifier and filter assembly includes a rectifier bridge and a filter capacitor. The AC input terminal of the rectifier bridge is connected to the lead-out terminal of the second winding. A timing control module, the output of which is connected to the lead-out end of the first winding; the timing control module has an output configuration that cyclically outputs on / off control signals according to the first to fourth steps. The first step is to energize the first winding to generate a dynamic magnetic field coupled with the fixed N-S magnetic poles formed by the second winding after rectification and filtering. The second step is to switch the angle of the excitation magnetic field generated by the first winding to cause the composite magnetic field to undergo circumferential displacement. The third step is to reset the magnetic circuit state; The fourth step is to return to the first step and repeat the process.

2. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 1, characterized in that, The stator's annular solid magnetic circuit structure is made of soft magnetic material, the inner peripheral wall of the stator is a smooth and continuous slotless magnetic circuit bearing surface, and the interior of the stator is a solid filling structure.

3. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 2, characterized in that, The soft magnetic material is silicon steel sheet, amorphous alloy, or soft magnetic composite material.

4. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 1, characterized in that, The rectifier and filter assembly also includes a freewheeling element, which is connected in parallel with the filter capacitor. When the first winding switches the excitation magnetic field angle in the second step, the freewheeling element provides a freewheeling path for the second winding to maintain the magnetic flux continuity of the fixed NS poles.

5. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 1, characterized in that, The timing control module includes a timing logic circuit and a power drive circuit. The timing logic circuit generates cyclic timing signals from the first step to the fourth step, and the power drive circuit controls the on / off state of the first winding according to the cyclic timing signals.

6. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 1, characterized in that, The timing control module is provided with a rotor position signal input terminal. The timing control module dynamically adjusts the duration of any one of the first to fourth steps according to the rotor position detection signal received by the rotor position signal input terminal.

7. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 6, characterized in that, The rotor position detection signal is provided by a Hall sensor, photoelectric encoder, or rotary transformer.

8. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 1, characterized in that, The timing control module has a current / voltage signal sampling terminal. The timing control module detects the current signal and / or voltage signal of the first winding or the second winding through the current / voltage signal sampling terminal to calculate the rotor position, and dynamically adjusts the output timing of the first to fourth steps according to the calculated rotor position.

9. The four-step dual-wire parallel-wound pure magnetic field commutated non-magnetic DC motor according to claim 1, characterized in that, In the dual-wire parallel winding structure, the wire diameter and number of turns of the first winding and the second winding are determined according to the rated power of the motor, and the winding direction of the first winding and the second winding are consistent.

10. A driving method for a four-step pure magnetic field commutated non-magnetic DC motor, characterized in that, The motor structure according to any one of claims 1 to 9 includes the following steps: The timing control module cyclically outputs on / off control signals to the first winding in steps one through four. The second winding converts the induced alternating current into unidirectional constant direct current through the rectifier and filter assembly, forming a fixed N-S magnetic pole array at each magnetic pole position of the rotor; The first winding sequentially generates a coupled magnetic field, switches the excitation magnetic field angle to cause circumferential displacement of the composite magnetic field, and resets the magnetic circuit state according to the on / off control signal. Repeat the above steps to drive the rotor to rotate continuously.

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