Linear rotary switched reluctance motor brake control system and method based on active energy optimization

Abstract

The invention discloses a linear rotary switched reluctance motor brake control system and method based on active energy optimization, the control system comprises a main control unit and a power converter, the main control unit comprises a controller, and a position sensor, a current sensor and a torque sensor which are connected with the controller; the power converter is connected with a controller in the main control unit, and the power converter comprises a linear unit power converter and a rotating unit power converter which are connected in parallel. Power converters of the linear unit and the rotating unit are electrically connected in parallel, a cross-degree-of-freedom energy transfer channel is formed, and active circulation of energy between the linear unit and the rotating unit is achieved; feedback energy is dynamically transferred and dissipated between the linear unit and the rotating unit instead of being simply released; according to the brake control system, a large capacitor is not needed to store feedback energy generated during braking, and the hardware cost of the system is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of switched reluctance motor, and particularly relates to a braking control system and method for a linear-rotary switched reluctance motor based on active energy optimization. BACKGROUND

[0002] Two-degree-of-freedom motors have been increasingly applied in industrial robots, textile machines and machine tools in recent years. The two-degree-of-freedom linear-rotary switched reluctance motor has become a research hotspot in recent years due to its simple structure, high reliability, strong fault tolerance and no permanent magnet material. However, in some application conditions requiring frequent braking operation, the two-degree-of-freedom linear-rotary switched reluctance motor generates a large amount of feedback energy due to frequent braking operation, which will impact the bus capacitor and cause capacitor damage. If a large capacitor is used, the system cost is increased. At the same time, the frequent feedback energy charging of the battery also easily damages the battery. Not only a great amount of energy is wasted, but also the large amount of feedback energy generated by braking has a very adverse effect on the equipment, so it is of great significance to carry out braking control research on the two-degree-of-freedom linear-rotary switched reluctance motor.

[0003] At present, a series of researches on the braking of switched reluctance motors have been carried out at home and abroad, and control methods such as regenerative braking and hybrid braking have been proposed. Although good results have been achieved, most of the researches are for single-degree-of-freedom switched reluctance motors, and the energy flow of the linear and rotary units needs to be managed at the same time. The braking of the two-degree-of-freedom linear-rotary switched reluctance motor is not completely applicable, so further research is still needed on the braking of the two-degree-of-freedom linear-rotary switched reluctance motor. SUMMARY

[0004] In order to solve the above problems, an embodiment of the application proposes a braking control system and method for an SMCSD-LRSRM (short magnetic circuit self-decoupling linear-rotary switched reluctance motor) based on active energy optimization.

[0005] The braking control system for the linear-rotary switched reluctance motor based on active energy optimization comprises a master control unit, a power converter, a linear unit winding and a rotary unit winding. The master control unit comprises a controller and a position sensor, a current sensor and a torque sensor connected with the controller. The power converter is connected with the controller in the master control unit, and comprises a linear unit power converter and a rotary unit power converter connected in parallel. The linear unit winding is controlled by the linear unit power converter. The rotary unit winding is controlled by the rotary unit power converter. Each phase winding of the rotary unit and each phase winding of the linear unit are independent of each other.

[0006] The linear unit power converter and the rotary unit power converter are both asymmetric half-bridge power converters, the rotary unit winding includes an A-phase winding, a B-phase winding and a C-phase winding, and the linear unit winding includes a D-phase winding, an E-phase winding and an F-phase winding.

[0007] The rotary unit power converter controls the power supply to supply power to the A-phase winding, the B-phase winding and the C-phase winding of the motor rotary unit, and the linear unit power converter controls the power supply to supply power to the D-phase winding, the E-phase winding and the F-phase winding of the motor linear unit.

[0008] The control method of the brake control system of the linear-rotary switched reluctance motor based on active energy optimization of the application, the linear-rotary switched reluctance motor has three brake modes of linear motion, rotary motion and spiral motion, wherein when the motor performs rotary motion brake, it is the separate brake of the rotary unit, including the following steps:

[0009] 1) brake starts;

[0010] 2) detect the mover position, judge which phase of the A-phase winding, the B-phase winding and the C-phase winding is in the conduction interval;

[0011] 3) control the conduction of the upper and lower switch tubes of the conduction phase bridge arm to allow the power supply to excite the phase winding in the conduction interval;

[0012] 4) after excitation, enter the brake mode, at this time, the mechanical energy of the mover is converted into electrical energy, and the feedback energy is generated in the conduction rotary unit winding;

[0013] 5) let the feedback energy generated by the brake flow to the bus capacitor and the linear unit winding;

[0014] 6) use model predictive control to control the on-off of the switch tubes of each phase bridge arm of the linear unit, adjust the energy flowing into the D-phase winding, the E-phase winding and the F-phase winding, so that the total thrust is zero;

[0015] 7) judge whether the motor speed is less than the set speed, if less than the set speed, the brake ends, if the motor speed is still greater than the set speed, continue to brake, return to step 2) to continue to detect the mover position.

[0016] In step 5), when the mover reaches the next phase conduction interval, the energy stored in the linear unit provides excitation energy for the conduction phase together with the power supply.

[0017] When the motor performs linear motion brake, it is the separate brake of the linear unit, including the following steps:

[0018] S01. brake starts;

[0019] S02. Detect the mover position, determine which phase of the D-phase winding, E-phase winding and F-phase winding is in the conduction interval;

[0020] S03. Control the conduction of the upper and lower switch tubes of the bridge arm corresponding to the conduction phase to allow the power supply to excite the phase winding in the conduction interval;

[0021] S04. After excitation, enter the braking mode, at which time the mechanical energy of the mover is converted into electrical energy to generate feedback energy in the conduction linear winding;

[0022] S05. Allow the feedback energy generated by braking to flow to the bus capacitor and the rotating unit winding;

[0023] S06. Use model predictive control to control the on-off of the switch tubes of each phase bridge arm of the rotating unit to adjust the energy flowing into the A-phase winding, B-phase winding and C-phase winding of the rotating unit so that the total torque is zero;

[0024] S07. Determine whether the linear speed of the motor is less than the set linear speed, if it is less than the set linear speed, the braking is ended, if the linear speed of the motor is still greater than the set linear speed, the braking continues, and returns to step S02 to continue detecting the mover position.

[0025] When the mover reaches the next phase conduction interval in S05, the energy in the rotating unit provides excitation energy for the conduction phase together with the power supply.

[0026] When the motor performs spiral motion braking, the following steps are included:

[0027] P01. Start braking;

[0028] P02. Detect the mover position, determine which phase of the D-phase winding, E-phase winding and F-phase winding in the linear unit winding is in the conduction interval;

[0029] P03. Control the conduction of the upper and lower switch tubes of the bridge arm corresponding to the conduction phase to allow the power supply to excite the phase winding in the conduction interval;

[0030] P04. After excitation, enter the braking mode, at which time the mechanical energy of the mover is converted into electrical energy to generate feedback energy in the conduction linear winding;

[0031] P05. Allow the feedback energy generated by braking to flow to the bus capacitor and the rotating unit winding;

[0032] P06. Detect the mover position, allow the feedback energy to flow to the A-phase winding, B-phase winding and C-phase winding in the conduction interval of the rotating unit winding, and excite the phase winding with the feedback energy;

[0033] P07. Determine whether the linear speed of the motor is less than the set linear speed. If it is less than the set linear speed, the mover position is detected to enter the rotary motion. If the linear speed of the motor is still greater than the set linear speed, the braking work is continued, and the step S02 is returned to continue detecting the mover position.

[0034] P08. Detect the mover position and determine which phase of the A-phase winding, the B-phase winding and the C-phase winding is in the conduction interval.

[0035] P09. By controlling the conduction of the upper and lower switch tubes of the corresponding bridge arm, the power supply is allowed to excite the phase winding in the conduction interval.

[0036] P10. After excitation, the braking mode is entered, and the mechanical energy of the mover is converted into electrical energy to generate feedback energy in the conduction rotary unit winding.

[0037] P11. The feedback energy generated by the braking is allowed to flow to the bus capacitor and the linear unit winding.

[0038] P12. The model predictive control is used to control the on-off of the switch tubes of the bridge arm of each phase of the linear unit, so as to adjust the energy flowing into the D-phase winding, the E-phase winding and the F-phase winding, and make the total thrust zero.

[0039] P13. Determine whether the motor speed is less than the set speed. If it is less than the set speed, the braking is ended. If the motor speed is still greater than the set speed, the braking work is continued, and the step P08 is returned to continue detecting the mover position.

[0040] The minimum bus capacitor required for braking of the rotary unit winding alone is

[0041]

[0042] In the formula, v dc is the rated voltage of the DC bus, i a is the rated current of the A-phase winding, L a is the maximum inductance of the A-phase winding, L l-max is the maximum inductance of the linear unit winding when the stator teeth and the mover teeth are completely aligned.

[0043] The minimum bus capacitor required for braking of the linear unit winding alone is

[0044]

[0045] In the formula, v dc is the rated voltage of the DC bus, i d is the rated current of the D-phase winding, L d is the maximum inductance of the D-phase winding, L r-maxLmax is the maximum value of three-phase inductance of the rotating unit winding when the inductance is taken at the fully aligned position of the mover.

[0046] The beneficial effects of the present application are that the present application forms a cross-degree-of-freedom energy transfer channel by electrically connecting the linear unit and the rotating unit power converter in parallel, actively circulates energy between the linear / rotating units, dynamically transfers and dissipates feedback energy between the linear and rotating units instead of simply discharging, realizes zero torque / thrust control, ensures that no additional mechanical output is generated during energy transfer, maintains system stability, realizes safe braking, avoids feedback energy impacting circuit elements, prolongs equipment life, and relative to the traditional braking method, the braking control system of the present application does not need a large capacitor to store feedback energy generated during braking, reducing the hardware cost of the system. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 is the principle diagram of the linear-rotating switched reluctance motor braking control system based on active energy optimization of the present application.

[0048] Figure 2 is the principle diagram of the main circuit of the present application.

[0049] Figure 3 is the circuit diagram of the power converter of the present application.

[0050] Figure 4 is the flowchart of the control method of the linear-rotating switched reluctance motor braking control system based on active energy optimization of the present application when the motor is in separate linear motion or separate rotating motion.

[0051] Figure 5 is the flowchart of the control method of the linear-rotating switched reluctance motor braking control system based on active energy optimization of the present application when the motor is in spiral motion.

[0052] Figure 6 is the excitation energy flow diagram of the present application taking phase A as an example.

[0053] Figure 7 is the feedback energy flow diagram of the present application taking phase A as an example.

[0054] Figure 8 is the position diagram of the linear unit stator and mover of the present application with phase D in the middle.

[0055] Figure 9 is the position diagram of the linear unit stator and mover of the present application with phase E in the middle.

[0056] Figure 10 is the result diagram of the linear unit thrust of the embodiment of the present application.

[0057] Figure 11The motor speed simulation diagram of the motor speed of the embodiment of the application is 500r / min.

[0058] Figure 12 The capacitor voltage of the new braking strategy used in the embodiment of the application and the capacitor voltage under the traditional braking mode are shown in the diagram. DETAILED DESCRIPTION

[0059] The embodiments of the application are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the application, and cannot be understood as a limitation of the application.

[0060] As shown in Figures 1-12 the active energy optimization-based linear-rotary switched reluctance motor braking control system of the application comprises a linear unit winding, a rotary unit winding, a main control unit and a power converter, the main control unit comprises a controller and a position sensor, a current sensor and a torque sensor connected with the controller; the power converter is connected with the controller in the main control unit, and the power converter comprises a linear unit power converter and a rotary unit power converter connected in parallel. The linear unit winding is controlled by the linear unit power converter; the rotary unit winding is controlled by the rotary unit power converter; and each phase winding of the rotary unit and each phase winding of the linear unit are independent of each other.

[0061] The controller can be a DSP module, an STM32 module or an FPGA.

[0062] The position sensor, the current sensor and the torque sensor are respectively adapted to collect position information, current information and torque / thrust information of the motor, and the controller sends a driving signal to the power converter according to the collected position, current and torque / thrust information, so that the power supply excites the motor winding to realize the braking function.

[0063] The power converter controls the braking and the flow of the feedback energy of the motor by receiving the driving signal of the main control unit.

[0064] As shown in Figure 1 and Figure 2 the embodiment takes SMCSD-LRSRM (short magnetic circuit self-decoupling linear-rotary switched reluctance motor) as an example, and the motor has two rotary motion unit stators, one linear motion unit stator and one common mover. The rotary unit winding comprises an A-phase winding, a B-phase winding and a C-phase winding, and the linear unit winding comprises a D-phase winding, an E-phase winding and an F-phase winding. The motor can realize rotary motion, linear motion and helical motion.

[0065] The power converter includes a rotating unit power converter and a linear unit power converter, both of which are completely identical and are asymmetric half-bridge power converters, since the rotating unit winding of the motor includes three phases of A-phase winding, B-phase winding and C-phase winding, and the linear unit winding includes three phases of D-phase winding, E-phase winding and F-phase winding, so that the two asymmetric half-bridge power converters each contain three asymmetric half-bridges.

[0066] As shown in Figure 3 , the rotating unit power converter and the linear unit power converter are connected in parallel to provide a channel for the feedback energy during braking to flow between the windings of the rotating unit and the linear unit.

[0067] Since the SMCSD-LRSRM motor has three braking modes of linear motion, rotary motion and spiral motion, the SMCSD-LRSRM braking control system based on active energy optimization of the application has three control methods, wherein when the motor performs rotary motion braking, it is a separate braking of the rotating unit, including the following steps: Figure 4

[0068] 1) Start braking;

[0069] 2) Detect the mover position and determine which of the A-phase winding, B-phase winding and C-phase winding is in the conduction interval;

[0070] 3) Control the conduction of the upper and lower switch tubes of the corresponding bridge arm to allow the power supply to excite the phase winding in the conduction interval;

[0071] During the motor movement, when the main control unit receives the braking signal, the motor starts to brake, and whether the A-phase winding, B-phase winding and C-phase winding are in the conduction interval is determined according to the motor mover position signal. If a phase is in the conduction interval, the phase is excited.

[0072] The phase current rises rapidly during excitation, and for the A-phase, the energy flow direction during excitation is as shown in Figure 6 , the switch tubes S1, S a1 , S a2 are turned on to form a power supply positive pole-S1-S a1 -A-phase winding-S a2 -power supply negative pole loop. The power supply supplies power to the winding to establish an excitation magnetic field.

[0073] 4) After excitation, enter the braking mode, at this time the mechanical energy of the mover is converted into electrical energy, and feedback energy is generated in the phase winding;

[0074] ​5) let the braking generated feedback energy flow to the bus capacitor and linear unit winding; when the mover to the next phase conduction interval, the energy stored in the linear unit and the power supply together for the conduction phase to provide excitation energy;

[0075] 6) using model predictive control, by controlling the on-off of the switch tube of each phase bridge arm of the linear unit, adjusting the energy flowing into the D phase winding, E phase winding and F phase winding, so that the total thrust is zero;

[0076] In order to prevent the feedback energy from impacting the bus capacitor, part of the feedback energy flows to the linear unit winding and is stored in the linear unit winding, as shown in Figure 7 At this time, the switch tubes S1, S a1 , S a2 are all turned off, and the current flows to the linear unit winding through diodes D a1 , D a2 . When the feedback energy flows to the linear unit winding, the model predictive control based on the lookup table is used to realize the zero thrust control of the linear unit. The controller controls the on-off of S d1 , S d2 , S e1 , S e2 , S f1 , S f2 in the linear unit power converter to store the feedback energy in the linear unit winding and make the thrust vector sum of the three phases of the linear unit zero.

[0077] The positions of the linear unit stator and mover are shown in Figure 8 , the stator has three windings D phase winding, E phase winding and F phase winding, when the linear unit winding is energized, the axial magnetic flux is generated, and the magnetic force line path is also divided into two parts, two parts flow out from the left and right sides of the second wide tooth salient pole, enter the mover salient pole through the air gap between the second wide tooth salient pole and the mover salient module salient pole, flow out from the mover salient pole, enter the second narrow tooth salient pole through the air gap between the adjacent second narrow tooth salient pole and the mover salient module salient pole, and form a loop through the stator yoke. At this time, the D phase winding is in full alignment position, and full alignment means that the two movers are in the middle position of the wide tooth and narrow tooth of the stator.

[0078] As shown in Figure 9 , the E phase winding is in the alignment position, and the D phase winding and the F phase winding are in the misalignment position. When the E phase winding is energized, the E phase winding mover is in the position of minimum magnetic resistance at this time, and will not generate left and right motion force. When the D phase winding is energized, according to the principle of minimum magnetic resistance, the mover will generate a right motion force until the alignment position. When the F phase winding is energized, according to the principle of minimum magnetic resistance, the mover will generate a left motion force until the alignment position.

[0079] So the motor mover is in any position, the D phase winding, E phase winding and F phase winding will produce two kinds of force direction to the left and to the right, the switch tube S d1 、S d2 control the excitation of D phase, S e1 、S e2 control the excitation of E phase, S f1 、S f2 control the excitation of F phase, when the feedback energy flows to the linear unit winding, the excitation of the corresponding phase winding is controlled by controlling the on-off of the switch tube, so that the vector sum of the thrust (left and right forces) generated by the D phase winding, E phase winding and F phase winding of the linear unit is zero. As shown in Fig. Figure 10 , the linear unit thrust is close to zero.

[0080] 7) judge whether the motor speed is less than the set speed, if less than the set speed, the braking is ended, if the motor speed is still greater than the set speed, the braking work is continued, and returns to step 2) to continue to detect the mover position.

[0081] After the braking mode is ended, if the motor speed is less than the set speed (for example, 5r / min), the braking is ended, if the motor speed is still greater than the set speed, the braking work is continued, and the next phase excitation of the rotary unit is carried out.

[0082] The control method of the linear-rotary switched reluctance motor braking control system based on active energy optimization of the application, when the motor performs linear motion braking, the linear unit is braked alone, and the feedback energy generated by the linear unit is stored in the rotary unit winding, as shown in Fig. Figure 4 , comprising the following steps:

[0083] S01. braking starts;

[0084] S02. detect the mover position, and judge which one of the D phase winding, E phase winding and F phase winding is in the conduction interval;

[0085] S03. by controlling the conduction of the upper and lower switch tubes of the bridge arm corresponding to the conduction phase, the power supply excites the phase winding in the conduction interval;

[0086] the corresponding switch tube is opened to enter the excitation mode; during excitation, the phase current rises rapidly, taking the D phase as an example, during excitation, the switch tubes S1, S d1 , S d2 are turned on, forming a power supply positive pole-S1-S d1 -D phase winding-S d2 -power supply negative pole circuit. The power supply supplies power to the winding to establish the excitation magnetic field.

[0087] S04. After the excitation ends, enter the braking mode, at this time the mechanical energy of the mover is converted into electrical energy, and the feedback energy is generated in the conducting linear winding.

[0088] S05. Let the feedback energy generated by braking flow to the bus capacitor and the rotating unit winding. When the mover enters the next phase conduction interval, the energy in the rotating unit provides excitation energy for the phase together with the power supply.

[0089] S06. Using model predictive control, adjust the energy flowing into the A-phase winding, B-phase winding and C-phase winding of the rotating unit by controlling the on-off of the switching tubes of each phase bridge arm of the rotating unit, so that the total torque is zero.

[0090] The feedback energy is distributed to the bus capacitor and the rotating unit winding; in order to prevent the feedback energy from impacting the bus capacitor, a part of the feedback energy flows to the rotating unit winding and is stored in the rotating unit winding. At this time, the switching tubes S1, S d1 , S d2 are all turned off, and the current flows to the rotating unit winding through diodes D d1 , D d2 . When the feedback energy flows to the rotating unit, the same model predictive control based on the lookup table as the linear unit is used to achieve zero torque control of the rotating unit.

[0091] S07. Determine whether the linear speed of the motor is less than the set linear speed, if it is less than the set linear speed, the braking ends, if the linear speed of the motor is still greater than the set linear speed, continue to brake, and return to step S02 to continue to detect the position of the mover.

[0092] The control method of the linear-rotary switched reluctance motor braking control system based on active energy optimization of the application, when the motor performs spiral motion braking, as shown in Figure 5 , includes the following steps:

[0093] P01. Start braking;

[0094] P02. Detect the position of the mover and determine which of the D-phase winding, E-phase winding and F-phase winding in the linear unit winding is in the conduction interval;

[0095] P03. By controlling the conduction of the upper and lower switching tubes of the bridge arm corresponding to the conducting phase, let the power supply excite the phase winding in the conduction interval;

[0096] P04. After the excitation ends, enter the braking mode, at this time the mechanical energy of the mover is converted into electrical energy, and the feedback energy is generated in the conducting linear winding;

[0097] P05. Let the feedback energy generated by braking flow to the bus capacitor and the rotating unit winding;

[0098] P06. Detecting the position of the mover, making the feedback energy flow to the A-phase winding, the B-phase winding and the C-phase winding of the rotating unit in the group of the conduction interval, so that the feedback energy excites the phase winding;

[0099] P07. Judging whether the linear speed of the motor is less than the set linear speed, if less than the set linear speed, detecting the position of the mover into the rotary motion, if the linear speed of the motor is still greater than the set linear speed, continuing to brake, returning to step S02 to continue detecting the position of the mover;

[0100] P08. Detecting the position of the mover, judging which phase of the A-phase winding, the B-phase winding and the C-phase winding is in the conduction interval;

[0101] P09. By controlling the conduction of the upper and lower switch tubes of the corresponding bridge arm, making the power excite the phase winding in the conduction interval;

[0102] P10. After excitation, entering the braking mode, at this time, the mechanical energy of the mover is converted into electrical energy, and the feedback energy is generated in the conduction rotating unit winding;

[0103] P11. Making the feedback energy generated by braking flow to the bus capacitor and the linear unit winding;

[0104] P12. Using model predictive control, by controlling the on-off of the switch tubes of each phase bridge arm of the linear unit, adjusting the energy flowing into the D-phase winding, the E-phase winding and the F-phase winding, so that the total thrust is zero;

[0105] P13. Judging whether the motor speed is less than the set speed, if less than the set speed, the braking ends, if the motor speed is still greater than the set speed, continuing to brake, returning to step P08 to continue detecting the position of the mover.

[0106] Embodiment

[0107] By comparing the traditional braking method and the braking method of the present application, the method of the present application requires smaller capacitance, which proves that the method of the present application can reduce the cost of using capacitance.

[0108] Traditional braking method: taking A-phase braking as an example, assuming that the bus voltage increment is Δv dc when feedback energy, and ignoring other energy losses, the bus capacitor when the rotating unit brakes alone can be calculated by the following formula:

[0109]

[0110] In the formula, v dc represents the rated voltage of the DC bus, C is the capacitance connected to the DC bus, i a is the A-phase rated current, is the A-phase flux linkage. According to the formula, the minimum capacitance C1min :

[0111]

[0112] Generally, in an asymmetric half-bridge power converter (AHPC converter), it is desirable that the bus voltage increment is Δv dc dc

[0113]

[0114] Therefore, simplifying formula (2) can obtain the minimum bus capacitance C 1min :

[0115]

[0116] In the formula, L a represents the maximum value of the A-phase inductance.

[0117] Taking the D-phase of the linear unit as an example, the minimum bus capacitance required when the linear unit brakes alone can be obtained by the same method:

[0118]

[0119] In the formula, i d is the rated current of the D-phase winding, and L d is the maximum value of the D-phase winding inductance.

[0120] The braking method provided by the application: taking the A-phase braking as an example, it is also assumed that the bus voltage increment is Δv dc when the feedback energy is taken, the rated voltage of the DC bus is v dc , and other energy losses are ignored, then the bus capacitance can be calculated as follows:

[0121]

[0122] Where C1 and C2 are the bus capacitances of the rotary unit and the linear unit respectively and have the same size. The A-phase winding current reaches the maximum value at the end of the braking / degaussing stage, at which time the capacitances C1 and C2 also reach the maximum voltage, and the current is zero, so i eq = i a . L a is the maximum value of the A-phase inductance, and i eq is the sum of the currents flowing to the D, E, and F phases.

[0123] L eq is the inductance value of the parallel connection of the three-phase windings of the linear unit, and the maximum value of the three-phase inductance is taken at the position where the stator teeth and the mover teeth are completely aligned, i.e., L l-max = L d :​​

[0124]

[0125] Therefore, the minimum bus capacitance required for braking the rotating unit alone can be calculated:

[0126]

[0127] Similarly, the minimum bus capacitance required for braking a linear unit alone can be obtained:

[0128]

[0129] Where L r-max =L a .

[0130] The maximum inductance L of phase A using the prototype a = 8.2458mH, maximum inductance of phase D L d =18.4461mH,i a =i d =20A, v dc =60V, the capacitance required for braking the rotary and linear units in the traditional method can be calculated using the motor parameters and formulas (4) and (5): C 1min =9.2mF, C 2min = 20.5mF. The capacitance required for braking the rotating and linear units in the manner proposed in this invention can be calculated using formulas (8) and (9): C' 1min =1.2mF, C' 2min =8.7 take C' 1min With C' 2min The larger value c' in 2min The bus capacitor serves as both the rotating and linear units. Compared to the minimum capacitance required using conventional braking methods, C' 2min Compared to C 1min With c 2min Both are small. This allows for cost reduction by using smaller capacitors.

[0131] Figure 11 The figure shown is a simulation diagram of the motor speed when the motor speed is 500 r / min using this method. Figure 12 The figure shows the voltage levels of the bus capacitor when using traditional braking methods and when using the proposed method. As can be seen from the figure, this method, while achieving rapid braking, can suppress the voltage rise of the bus capacitor, reducing the risk of energy feedback to the bus and damaging electronic components, thus achieving safe and rapid braking of the motor. The comparison also shows that the method of this application requires a smaller capacitor than the traditional method, reducing the cost of capacitor usage.

[0132] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are exemplary, and are not to be construed as limiting the present application, and any changes, modifications, replacements, and variations of the above embodiments made by those skilled in the art are within the scope of the present application.

Claims

1. A braking control system for a linear rotary switched reluctance motor based on active energy optimization, characterized by, include: The main control unit includes a controller and a position sensor, a current sensor and a torque sensor connected to the controller; A power converter, which is connected to a controller in a main control unit, and the power converter includes a linear unit power converter and a rotating unit power converter; A linear unit winding, wherein the linear unit winding is controlled by a linear unit power converter; The rotating unit winding is controlled by the rotating unit power converter; and the linear unit power converter is connected in parallel with the rotating unit power converter, and each phase winding of the rotating unit is independent of each phase winding of the linear unit.

2. The active energy optimization based braking control system for linear rotary switched reluctance motor as claimed in claim 1 wherein, Both the linear unit power converter and the rotating unit power converter are asymmetrical half-bridge power converters. The rotating unit windings include phase A windings, phase B windings, and phase C windings, while the linear unit windings include phase D windings, phase E windings, and phase F windings.

3. The active energy optimization based braking control system for linear rotary switched reluctance motor as claimed in claim 1 wherein, The rotating unit power converter control power supply supplies power to the A-phase, B-phase, and C-phase windings of the rotating unit winding; the linear unit power converter control power supply supplies power to the D-phase, E-phase, and F-phase windings of the linear unit winding.

4. A control method of a braking control system of a linear rotary switched reluctance motor based on active energy optimization according to any one of claims 1-3, characterized in that, The linear-rotary switched reluctance motor has three braking modes: linear motion, rotary motion, and helical motion. When the motor brakes during rotary motion, the braking of the rotating unit is performed separately, including the following steps: 1) Braking begins; 2) Detect the position of the mover to determine which phase of the A-phase winding, B-phase winding, or C-phase winding is in the conducting range; 3) By controlling the conduction of the upper and lower switching transistors of the corresponding bridge arm, the power supply excites the phase winding in the conduction range; 4) After the excitation ends, the vehicle enters the braking mode. At this time, the mechanical energy of the mover is converted into electrical energy, which generates feedback energy in the conducting rotating unit winding. 5) Direct the feedback energy generated by braking to the bus capacitor and the linear unit winding; 6) Using model predictive control, the energy flowing into the D-phase winding, E-phase winding and F-phase winding is adjusted by controlling the on and off of the switching transistors of each phase arm of the linear unit, so that the total thrust is zero. 7) Determine if the motor speed is less than the set speed. If it is less than the set speed, the braking ends. If the motor speed is still greater than the set speed, continue the braking operation and return to step 2) to continue detecting the mover position.

5. The control method of the braking control system of the linear rotary switched reluctance motor based on active energy optimization according to claim 4, characterized in that, In step 5), when the mover moves to the next phase conduction interval, the energy stored in the linear unit, together with the power supply, provides excitation energy for the conduction phase.

6. The control method of the active energy-optimized braking control system of the linear-rotary switched reluctance motor according to claim 4, characterized in that, When the motor performs linear motion braking, it brakes the linear unit individually, including the following steps: S01. Braking begins; S02. Detect the position of the mover and determine which phase of the D-phase winding, E-phase winding, and F-phase winding is in the conduction range; S03. By controlling the conduction of the upper and lower switching transistors of the corresponding bridge arm, the power supply excites the phase winding in the conduction range; S04. After the excitation ends, the vehicle enters the braking mode. At this time, the mechanical energy of the mover is converted into electrical energy, which generates feedback energy in the conducting linear winding. S05. Direct the feedback energy generated by braking to the bus capacitor and the rotating unit winding; S06. Using model predictive control, the on-off of the switch tubes of the bridge arms of each phase of the rotating unit is controlled to adjust the energy flowing into the A-phase winding, B-phase winding and C-phase winding of the rotating unit so that the total torque is zero; S07. It is judged whether the linear speed of the motor is less than the set linear speed. If it is less than the set linear speed, the braking is ended. If the linear speed of the motor is still greater than the set linear speed, the braking is continuously performed, and the mover position is detected again in step S02.

7. The control method of the active energy-optimized braking control system of the linear-rotary switched reluctance motor according to claim 6, characterized in that, In the S05, when the mover reaches the next phase conduction interval, the energy in the rotating unit provides excitation energy for the conduction phase together with the power supply.

8. The control method of the active energy-optimized braking control system of the linear-rotary switched reluctance motor according to claim 4, characterized by, When the motor performs the spiral motion braking, the following steps are included: P01. Braking starts; P02. The mover position is detected, and it is judged which phase of the D-phase winding, E-phase winding and F-phase winding of the linear unit winding is in the conduction interval; P03. The upper and lower switch tubes of the bridge arm corresponding to the conduction phase are turned on to allow the power supply to excite the phase winding in the conduction interval; P04. After the excitation is ended, the braking mode is entered, at this time, the mechanical energy of the mover is converted into electric energy to generate feedback energy in the conduction linear winding; P05. The feedback energy generated by the braking is allowed to flow to the bus capacitor and the rotating unit winding; P06. The mover position is detected, and the feedback energy is allowed to flow to the group of A-phase winding, B-phase winding and C-phase winding of the rotating unit winding in the conduction interval, so that the feedback energy excites the phase winding; P07. It is judged whether the linear speed of the motor is less than the set linear speed. If it is less than the set linear speed, the mover position is detected to enter the rotating motion. If the linear speed of the motor is still greater than the set linear speed, the braking is continuously performed, and the mover position is detected again in step S02; P08. The mover position is detected, and it is judged which phase of the A-phase winding, B-phase winding and C-phase winding is in the conduction interval; P09. The upper and lower switch tubes of the bridge arm corresponding to the conduction phase are turned on to allow the power supply to excite the phase winding in the conduction interval; P10. After the excitation is ended, the braking mode is entered, at this time, the mechanical energy of the mover is converted into electric energy to generate feedback energy in the conduction rotating unit winding; P11. The feedback energy generated by the braking is allowed to flow to the bus capacitor and the linear unit winding; P12. Using model predictive control, the on-off of the switch tubes of the bridge arms of each phase of the linear unit is controlled to adjust the energy flowing into the D-phase winding, E-phase winding and F-phase winding so that the total thrust is zero; P13. It is judged whether the motor speed is less than the set speed. If it is less than the set speed, the braking is ended. If the motor speed is still greater than the set speed, the braking is continuously performed, and the mover position is detected again in step P08.

9. The control method of the active energy-optimized braking control system of the linear rotary switched reluctance motor according to claim 4, characterized in that, The minimum bus capacitor required when the rotating unit winding is braked alone is where v dc is the rated voltage of the DC bus, i a is the rated current of the A-phase winding, L a is the maximum inductance of the A-phase winding, L l-max is the maximum inductance of the three-phase inductance of the linear unit winding when the stator teeth and the mover teeth are completely aligned.

10. The control method of the active energy-optimization-based braking control system of the linear-rotary switched reluctance motor according to claim 6, characterized by, The minimum bus capacitor required when the linear unit winding is braked alone is where v dc is the rated voltage of the DC bus, i d is the rated current of the D-phase winding, L d is the maximum inductance of the D-phase winding, L r-max is the maximum inductance of the three-phase inductance of the rotating unit winding when the rotor is completely aligned.

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