Fault-tolerant control system and method for open-circuit fault of stator segment of long-stator segmented linear motor

Abstract

The invention provides a fault-tolerant control system and method for open-circuit faults of stator segments of a long-stator segmented linear motor, the long-stator segmented linear motor system at the same time comprises n unit motors, and each unit motor comprises a converter, a change-over switch and a stator segment connected to the converter through the switch, the neutral points of the stator windings of the stator sections in the same unit motor are connected together through a cable, and the change-over switch corresponding to the phase winding of the next stator section of the unit motor is switched on according to the specific phase of the open-circuit fault of the inner stator section of the unit motor or the change-over switch. According to the method, the open-phase operation of the power supply converter caused by the open-circuit fault of the stator section is avoided, and the reduction and the thrust fluctuation of the thrust of the unit motor and the total thrust of the system can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of linear motor fault-tolerant control, and in particular to a fault-tolerant control system and method for an open-circuit fault of a stator segment of a long-stator segmented linear motor. Background Art

[0002] In order to increase the speed of long-stator linear motors used in ultra-high-speed electromagnetic drive, magnetic levitation rail transit and other fields, and reduce the single-phase voltage withstand requirements of a single converter, long-stator linear motors adopt stator armature segmented power supply and multi-phase motors. The segmented stator segments are connected to the converter through a switching switch. When the mover approaches and gradually enters the stator segment, the switching switch connected to the stator segment is closed, and current is passed through the stator segment; when the mover leaves the stator segment, the switching switch connected to the stator segment is disconnected. Due to the long stator segment, when an open circuit fault occurs in a single stator segment and the switching switch connected to it, the system is in a fault state when the mover is running in the faulty stator segment, and the system is in a healthy operation state when the mover is running in the non-faulty stator segment, that is, the mover is running alternately in the faulty segment and the non-faulty segment, and the force on the mover varies greatly, which seriously affects the stable operation of the system.

[0003] For multi-phase motor fault-tolerant control, the paper "Fault-tolerant vector control strategy for single-phase open-circuit fault of five-phase permanent magnet synchronous motor" (Xiong Cong [J] Proceedings of the CSEE, 2019, 39(23): 7055-7064) constructs a new degraded coordinate transformation matrix to obtain a new motor decoupling model after an open-circuit fault and implements vector control. For fault-tolerant control of long stator segmented linear systems, the paper "Open-circuit thrust fluctuation suppression of segmented power supply permanent magnet linear synchronous motor converter based on harmonic injection" (Liu Jinhai [J] Proceedings of the CSEE, 2024, 44(13): 5308-5319) uses harmonic current injection to reduce the thrust fluctuation of the system after an open-circuit fault occurs in one of the multiple unit motors.

[0004] The existing fault-tolerant control strategy after a motor failure cannot achieve good operation in a healthy state. There are problems such as large thrust drop and thrust fluctuation of the unit motor with open circuit failure, and unstable total thrust of the system. In particular, the long stator segmented linear motor system is composed of multiple unit motors. After an open circuit failure occurs in a single stator segment of the unit motor, it is very difficult for the faulty unit motor to cooperate with the healthy unit motor. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a fault-tolerant control system and method for an open-circuit fault of a stator segment of a long stator segment linear motor. According to the specific phase of the stator segment or the switch that is powered by the converter in the unit motor at the moment and has an open-circuit fault, the switch corresponding to the phase winding of the next stator segment of the unit motor is opened, and then the unit motor current disturbance caused by the stator segment open-circuit fault is reduced by a feedforward disturbance observer, and the unit motor thrust and the total thrust drop of the system caused by the stator segment open-circuit fault are reduced by injecting harmonics of the unit motor current. For an open-circuit fault of a single stator segment of the unit motor, the mover is only in a fault-tolerant operating state in the faulty stator segment, and the mover is in a healthy operating state in the non-faulty stator segment. Therefore, the designed fault-tolerant control strategy can not only operate well in a healthy state, but also reduce the thrust drop and thrust fluctuation of the unit motor under an open-circuit fault, thereby ensuring the stability of the total thrust of the system.

[0006] To achieve the above object, the present invention adopts the following scheme: A fault-tolerant control system for an open-circuit fault of a stator segment of a long stator segment linear motor. At the same time, the long stator segment linear motor system comprises n unit motors, each unit motor comprises a converter, a switching switch and a stator segment connected to the converter via the switch, and a linear motor mover part within the stator segment. The mover is located within the n consecutive stator segments, and the stator winding neutral points of the stator segments within the same unit motor are connected together via cables.

[0007] The present invention also provides a fault-tolerant control method for an open-circuit fault of a stator segment of a long stator segmented linear motor, comprising: If a phase open circuit fault occurs in the stator segment or the switching switch of the j-th unit motor, the fault index matrix G of the j-th unit motor is obtained. j =[g jA , g jB , g jC , g jD , g jE , g jF ] T , where g jA , g jB , g jC , g jD , g jE , g jF is the fault index of phases A, B, C, D, E, and F of the j-th unit motor, g jA , g jB , g jC , g jD , g jE , g jFThe value can only be 0 or 1, 0 means that there is no open circuit fault in the phase, and 1 means that there is an open circuit fault in the phase; j = 1~n, j is a natural number; the superscript T represents the transpose of the matrix; According to the specific phase of the stator segment or switching switch driven by the inverter in the unit motor at this moment where an open circuit fault occurs, the switching switch corresponding to the phase winding of the next stator segment of the jth unit motor is opened, and the inverter supplies power to the phase winding of the next stator segment, so that the unit motor continues to maintain the operation of the dual three-phase winding.

[0008] Furthermore, for a dual three-phase linear motor with two unit motors and a motor system with a mover length shorter than a single stator segment, the motor thrust is for: ; During the operation of the mover, when an open circuit fault occurs in a stator segment of the first unit motor or a phase of a switching switch, after the specific phase of the unit motor open circuit fault is detected and the switching switch connected to the corresponding phase winding power supply of the next stator segment powered by the same converter is opened, the motor thrust is: ; Among them, n p is the pole pair number, is the pole pitch of the linear motor, is the electrical angle of the linear motor rotor, is the coupling factor of the first unit motor, is the fundamental flux amplitude of the permanent magnet flux of the motor system rotor, i 1d , i 1q , i 1z1 ,i 1z2 ,i 2d , i 2q , i 2z1 , i 2z2 are the currents of the first unit motor and the second unit motor in the d-axis, q-axis, z1 sub-plane, and z2 sub-plane of the synchronous rotating coordinate system respectively; The motor current i to the fault unit 1d and i 1q Inject harmonic current into the current reference value: ; in, is the expected current of the unit motor q axis, k is the harmonic current parameter to be determined; Taking the output of maximum electromagnetic thrust as the optimization target, the value of the harmonic current parameter k to be determined is obtained, and the reference value of the injected harmonic current is further calculated; According to the current reference value of the j-th unit motor, the j-th unit motor current controller output phase voltage reference value U is obtained through the current controller. ct-jABCDEF .

[0009] Furthermore, a sliding mode disturbance observer is designed as a disturbance observer, which measures the phase current value I of the faulty unit motor. jABCDEF And phase voltage value U me-jABCDEF After the coordinate transformation matrix T 64 Get the current and voltage matrix I of the synchronous rotating coordinate system d axis, q axis, z1 sub-plane, and z2 sub-plane jdqz1z2 , U me-jdqz1z2 , and use it as the input of the disturbance observer. The output reference value of the disturbance observer is U ob-jdqz1z2 After the coordinate transformation matrix T 64 The inverse matrix of U ob-jABCDEF : ; Will U ob-jABCDEF =[u ob-jA , u ob-jB , u ob-jC , u ob-jD , u ob-jAE , u ob-jF ] T and fault index G j Perform Hadamard product operation to obtain the j-th unit motor feedforward voltage reference value U fe-jABCDEF for: ; Among them, u ob-jA 、u ob-jB 、u ob-jC 、u ob-jD 、u ob-jE 、u ob-jF They are the output reference value matrix U of the observer respectively. ob-jABCDEF The output reference values ​​of the observers for phases A, B, C, D, E, and F are: is the Hadamard product operation.

[0010] Furthermore, the j-th unit motor phase voltage reference value U jABCDEF For U jABCDEF =U fe-jABCDEF +U ct-jABCDEF .

[0011] Furthermore, the long stator segmented linear motor is a long stator segmented permanent magnet synchronous linear motor or a long stator segmented asynchronous linear motor or other types of long stator segmented linear motors.

[0012] Furthermore, based on the idea of ​​the fault-tolerant control method for an open-circuit fault in a stator segment of a long-stator segmented linear motor, it can be extended to fault-tolerant control in the event of a single-phase open-circuit fault in a stator segment of other multi-phase linear motors or a single-phase open-circuit fault in a switching switch.

[0013] Further, according to the idea of ​​the fault-tolerant control method for the open circuit fault of the stator segment of the long stator segment linear motor, a system including n unit motors has m unit motors with one or more phases open circuit. The method for the system including 2 unit motors with one unit motor with one phase open circuit can be referred to. After detecting the specific phase of the unit motor open circuit fault, the switching switch connected to the corresponding phase winding power supply of the next stator segment powered by the same inverter is opened, and then the reference value of the phase voltage of the faulty unit motor is derived and determined for fault-tolerant control; m=1~n, m is a natural number.

[0014] The beneficial effects of the present invention are: The present invention opens the switch corresponding to the phase winding of the next stator segment of the unit motor according to the specific phase of the stator segment or the switch powered by the converter in the unit motor at the moment, and then reduces the unit motor current disturbance caused by the stator segment open circuit fault through the feedforward disturbance observer, and reduces the unit motor thrust and system total thrust reduction caused by the stator segment open circuit fault by injecting current harmonics into the unit motor. The fault-tolerant control strategy of the present invention can operate well in a healthy state, and can also reduce the unit motor thrust reduction and thrust fluctuation under the open circuit fault, and ensure the stability of the system total thrust. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A system structure diagram of two converters of the present invention supplying power to a dual three-phase double-sided long-stator segmented linear motor; Figure 2 It is a schematic diagram of the stator winding power-on of the dual three-phase double-side long stator segmented linear motor of the present invention when a single stator segment has an open circuit fault; Figure 3 It is a fault-tolerant control block diagram of the double-sided long stator segmented linear motor of the present invention; Figure 4 The two unit motor phase currents I of the present invention are 1ABCDEF ,I 2ABCDEF Waveform diagram of Figure 5 It is a waveform diagram of the thrust of the two unit motors and the total thrust of the motor system of the present invention.

[0016] In the figure, 1_1, the first converter, 1_2, the second converter, 2_1, the power supply output bus of the first converter, 2_2, the power supply output bus of the second converter, 4_1, 4_2, 4_3, 4_4, ..., 4_2m-1, 4_2m corresponding to the 4_1, 4_2, 4_3, 4_4, ..., 4_2m-1, 4_2m switching switches in the order of stator segment connection, 3_1, 3_2, 3_3, 3_4, ..., 3_2m-1, 3_2m double-sided long stator segmented linear motor in sequence of the 3rd segment. _1, 3_2, 3_3, 3_4, ..., 3_2m-1, 3_2m stator segment, 6, the mover of the motor system, 5_1_1, 5_1_2, 5_2_1, 5_2_2 are the neutral point cable connection line of the first three-phase winding of the double three-phase winding of the first unit motor, the neutral point cable connection line of the second three-phase winding of the double three-phase winding of the first unit motor, the neutral point cable connection line of the first three-phase winding of the double three-phase winding of the second unit motor, and the neutral point cable connection line of the second three-phase winding of the double three-phase winding of the second unit motor, and m is a positive integer. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other. The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, and the implementations cited are only used to explain the present invention and do not limit the scope of the present invention.

[0018] like Figure 1 As shown, the length of a single stator segment of the dual three-phase double-side long stator segment is greater than the length of the mover, and the mover interlinks the magnetic field with at most two stator segment windings. In order to maintain a stable thrust, at least two stator segments are powered at any time.

[0019] The 3_1st, 3_3rd, ..., 3_2m-1st stator segments are connected to the power supply output bus 2_1 of the first converter 1_1 through the 4_1st, 4_3rd, ..., 4_2m-1st switching switches, and the 3_2nd, 3_4th, ..., 3_2mstator segments are connected to the power supply output bus 2_2 of the second converter 1_2 through the 4_2nd, 4_4th, ..., 4_2mstitching switches. The first three-phase winding neutral point of the double three-phase winding of the stator segments 3_1, 3_3, ..., 3_2m-1 of the first unit motor is connected through a cable connection line 5_1_1, the second three-phase winding neutral point of the double three-phase winding of the stator segments 3_1, 3_3, ..., 3_2m-1 of the first unit motor is connected through a cable connection line 5_1_2, the first three-phase winding neutral point of the double three-phase winding of the stator segments 3_2, 3_4, ..., 3_2m of the second unit motor is connected through a cable connection line 5_2_1, and the second three-phase winding neutral point of the double three-phase winding of the stator segments 3_2, 3_4, ..., 3_2m of the second unit motor is connected through a cable connection line 5_2_2. A single converter only supplies power to one stator segment at any time, and supplies power to the corresponding stator segment by switching the switch according to the stator position of the mover 6 of the motor system in the linear motor.

[0020] It should be understood that when the motor system is operating at low speed or under other operating conditions, in order to reduce the number of switching switches, the lengths of the segmented stator segments can be equal or unequal. The fault-tolerant control system and method for open-circuit faults of stator segments of a long-stator segmented linear motor proposed in the present invention are applicable under both connection modes.

[0021] Optionally, in some application fields, the types of long stator segmented linear motors applicable to the present invention are long stator segmented permanent magnet synchronous linear motors or long stator segmented asynchronous linear motors and other types of long stator segmented linear motors.

[0022] Figure 2 The schematic diagram is a stator winding power-on diagram of the dual three-phase double-side long stator segmented linear motor of the present invention when a single stator segment has an open circuit fault. Figure 2 For example, when the rotor is running between the first stator segment and the second stator segment, the A phase of the first stator segment has an open circuit fault. After the A phase has an open circuit fault, the A phase switch of the third stator segment is turned on, and current flows into the winding of this phase. The B, C, D, E, and F phases of the first stator segment and the A phase of the third stator segment together form a double three-phase winding operation, and the converter continues to maintain six-phase operation. 1A 、i 1B 、i 1C 、i 1D 、i 1E 、i 1F are the A, B, C, D, E, and F phase currents of the first unit motor.

[0023] Figure 3 The fault-tolerant control block diagram of the double-sided long stator segmented linear motor of the present invention is shown in FIG. First, the phase current I of the first and second unit motors are measured respectively by current and voltage sensors. 1ABCDEF ,I 2ABCDEF And phase voltage U 1ABCDEF , U 2ABCDEF , the current matrix and voltage matrix I of the first and second unit motors in the synchronous rotating coordinate system dq z1 z2 sub-plane can be obtained through the coordinate transformation matrix corresponding to formula (1): 1dqz1z2 ,I 2dqz1z2 , U 1dqz1z2 , U 2dqz1z2 ; (1) in, is the electrical angle of the linear motor rotor.

[0024] Furthermore, according to the phase current I of the unit motor 1ABCDEF ,I 2ABCDEF , through the fault detection method, detect whether the unit motor has an open circuit fault, and obtain the unit motor fault index G1=[g 1A , g 1B , g 1C , g 1D , g 1E , g 1F ] T 、G2=[g 2A , g 2B , g 2C , g 2D , g 2E , g 2F ] T , where g 1A , g 1B , g 1C , g 1D , g 1E , g 1F is the fault index of phases A, B, C, D, E, and F of the first unit motor, g 2A , g 2B , g 2C , g 2D , g 2E , g 2F is the fault index of phases A, B, C, D, E, and F of the second unit motor, g 1A , g 1B , g 1C , g 1D , g 1E , g 1F , g 2A , g 2B , g2C , g 2D , g 2E , g 2F The value can only be 0 or 1 (0 means that there is no open circuit fault in the phase, and 1 means that there is an open circuit fault in the phase); Further, according to the specific phase of the stator segment or the switch powered by the converter in the unit motor at the moment where the open circuit fault occurs, the switch corresponding to the phase winding of the next stator segment of the j-th unit motor is opened to avoid the unit motor from running in phase loss; For a motor system consisting of two unit motors of a dual three-phase linear motor and a mover length shorter than a single stator segment, the motor thrust is for: (2) When an open circuit fault occurs in a phase of the first unit motor during operation of the mover, after detecting the specific phase of the unit motor open circuit fault, the switch connected to the corresponding phase winding power supply of the next stator segment powered by the same converter is turned on. At this time, the motor thrust is (3) Among them, n p is the pole pair number, is the pole pitch of the linear motor, is the coupling factor of the first unit motor, is the fundamental flux amplitude of the permanent magnet flux of the motor system rotor, i 1d , i 1q , i 1z1 , i 1z2 ,i 2d , i 2q , i 2z1 , i 2z2 are the currents of the first unit motor and the second unit motor in the d-axis, q-axis, z1 sub-plane, and z2 sub-plane of the synchronous rotating coordinate system respectively; The motor current i to the fault unit 1d and i 1q Inject harmonic current into the current reference value: (4) in, is the expected current of the unit motor q axis, k is the harmonic current parameter to be determined; Taking the output of maximum electromagnetic thrust as the optimization target, the value of the harmonic current parameter k to be determined is obtained, and the reference value of the injected harmonic current is further calculated; According to the current reference value of the j-th unit motor, the j-th unit motor current controller output phase voltage reference value U is obtained through the current controller. ct-jABCDEF .

[0025] Design a disturbance observer, which can be designed as a sliding mode disturbance observer, an extended state observer, a reduced order observer, and other types of observers, and transform the phase current I of the healthy and faulty unit motors jdqz1z2 And phase voltage U jdqz1z2 As the input of the observer, the output reference value of the observer is U ob-jdqz1z2 , and then the output reference value matrix U is obtained by the inverse transformation of the coordinate transformation corresponding to formula (1) ob-jABCDEF .

[0026] Furthermore, U ob-jABCDEF and fault index G j Perform Hadamard product operation to obtain the reference value U of the j-th unit motor feedforward voltage matrix fe-jABCDEF for: (5) Among them, u ob-jA 、u ob-jA 、u ob-jA 、u ob-jA 、u ob-jA 、u ob-jA They are the output reference value matrix U of the observer respectively. ob-jABCDEF The output reference values ​​of phase A, phase B, phase C, phase D, phase E, and phase F are is the Hadamard product operation.

[0027] Furthermore, the phase voltage reference values ​​of the first unit motor and the second unit motor are obtained as follows: U 1ABCDEF =U fe-1ABCDEF +U ct-1ABCDEF , U 2ABCDEF =U fe-2ABCDEF +U ct-2ABCDEF .

[0028] Figure 4 The two unit motor phase currents I of the present invention are 1ABCDEF ,I 2ABCDEF Waveform diagram. A phase A open circuit fault occurred in one of the stator segments of the odd stator segment or the switch connected to the stator segment. Before 5.9838 seconds, the mover was running in the healthy odd stator segment and the healthy even stator segment. At 5.9838 seconds, the mover left the previous healthy odd stator segment and will enter the faulty stator segment. Between 5.9838 seconds and 6.024 seconds, the mover was running in the faulty odd stator segment and the healthy even stator segment; between 5.9838 seconds and 5.985 seconds, due to the phase A open circuit fault, the I of the first unit motor 1ABCDEFThe remaining healthy phase currents are disordered; at 5.985 seconds, the open circuit fault phase is detected, the switch corresponding to the A phase winding of the next odd stator segment is turned on, and the harmonic current is injected to keep the first unit motor in dual three-phase operation. After a short dynamic process, the six-phase current trajectory of the unit motor is the same as the expected current value. After 6.024 seconds, the motor runs between the healthy odd stator segment and the healthy even stator segment. 2ABCDEF The waveform diagram shows that the open circuit fault of the first unit motor and the subsequent fault-tolerant control strategy have no effect on the current control of the second unit motor.

[0029] Figure 5 The thrust waveforms of the two motor units and the total thrust of the motor system of the present invention are shown in FIG. em The electromagnetic thrust F of the first unit motor 1em and the electromagnetic thrust F of the second unit motor 2em Together. An A-phase open circuit fault occurred in one of the stator segments of the odd-numbered stator segments or the switch connected to the stator segment. Before 5.9838 seconds, the mover operated in the healthy odd-numbered stator segments and the healthy even-numbered stator segments, and the total thrust fluctuation of the unit motor and the system was low. At 5.985 seconds, the open circuit fault phase was detected, the switch corresponding to the A-phase winding of the next odd-numbered stator segment was opened, and the harmonic current was injected, so that the first unit motor continued to maintain dual three-phase operation, so that the total thrust fluctuation of the unit motor and the system was within an acceptable range. After 6.024 seconds, the mover operated between the healthy odd-numbered stator segments and the healthy even-numbered stator segments, and the total thrust of the unit motor and the system returned to the low thrust fluctuation range. According to the waveform diagram of the unit motor and the total thrust of the system, it can be seen that the proposed fault-tolerant control method and system can not only operate well in a healthy state, but also reduce the thrust drop and thrust fluctuation of the unit motor under an open circuit fault, and ensure the stability of the total thrust of the system.

[0030] Although the above describes the illustrative specific embodiments of the present invention to facilitate those skilled in the art to understand the present invention, and it should be clear that the present invention is not limited to the scope of the specific embodiments, for those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations using the concept of the present invention are protected.

Claims

1. A fault-tolerant control system for stator segment open circuit faults in a long stator segment linear motor, characterized in that: At the same time, the long stator segmented linear motor system includes n unit motors, each unit motor includes an inverter, a switching switch and a stator segment connected to the inverter through the switch, and a linear motor rotor part in the stator segment. The rotor is located in the n consecutive stator segments, and the neutral points of the stator windings of the stator segments in the same unit motor are connected together by cables.

2. The fault-tolerant control method of a fault-tolerant control system for a stator segment open circuit fault of a long stator segmented linear motor according to claim 1, characterized in that: include: If a phase open circuit fault occurs in the stator segment or the switching switch of the j-th unit motor, the fault index matrix G of the j-th unit motor is obtained. j =[g jA , g jB , g jC , g jD , g jE , g jF ] T , where g jA , g jB , g jC , g jD , g jE , g jF is the fault index of phases A, B, C, D, E, and F of the j-th unit motor, g jA , g jB , g jC , g jD , g jE , g jF The value can only be 0 or 1, 0 means that there is no open circuit fault in the phase, 1 means that there is an open circuit fault in the phase; j=1~n, j is a natural number; The superscript T indicates the transpose of the matrix; According to the specific phase of the stator segment or switching switch driven by the inverter in the unit motor at this moment where an open circuit fault occurs, the switching switch corresponding to the phase winding of the next stator segment of the jth unit motor is opened, and the inverter supplies power to the phase winding of the next stator segment, so that the unit motor continues to maintain the operation of the dual three-phase winding.

3. The fault-tolerant control method according to claim 2, characterized in that: For the two unit motors of the dual three-phase linear motor, that is, n=2, the motor system with a shorter rotor length than a single stator segment, when running normally, the motor thrust for: ； During the operation of the mover, when an open circuit fault occurs in a stator segment of the first unit motor or a phase of a switching switch, after the specific phase of the unit motor open circuit fault is detected and the switching switch connected to the corresponding phase winding power supply of the next stator segment powered by the same converter is opened, the motor thrust is: ； Among them, n p is the pole pair number, is the pole pitch of the linear motor, is the electrical angle of the linear motor rotor, is the coupling factor of the first unit motor, is the fundamental flux amplitude of the permanent magnet flux of the motor system rotor, i 1d , i 1q , i 1z1 , i 1z2 ,i 2d , i 2q , i 2z1 , i 2z2 are the currents of the first unit motor and the second unit motor in the d-axis, q-axis, z1 sub-plane, and z2 sub-plane of the synchronous rotating coordinate system respectively; The motor current i to the fault unit 1d and i 1q Inject harmonic current into the current reference value: ； in, is the expected current of the unit motor q axis, k is the harmonic current parameter to be determined; Taking the output of maximum electromagnetic thrust as the optimization target, the value of the harmonic current parameter k to be determined is obtained, and the reference value of the injected harmonic current is further calculated; According to the current reference value of the j-th unit motor, the j-th unit motor current controller output phase voltage reference value U is obtained through the current controller. ct-jABCDEF .

4. The fault-tolerant control method according to claim 2, characterized in that: The sliding mode disturbance observer is designed as a disturbance observer, which measures the phase current value I of the faulty unit motor. jABCDEF And phase voltage value U me-jABCDEF After coordinate transformation matrix T 64 Get the current and voltage matrix I of the synchronous rotating coordinate system d axis, q axis, z1 sub-plane, and z2 sub-plane jdqz1z2 , U me-jdqz1z2 , and use it as the input of the disturbance observer. The output reference value of the disturbance observer is U ob-jdqz1z2 After coordinate transformation matrix T 64 The inverse matrix of U ob-jABCDEF : ； Will U ob-jABCDEF =[u ob-jA , u ob-jB , u ob-jC , u ob-jD , u ob-jAE , u ob-jF ] T and fault index G j Perform Hadamard product operation to obtain the j-th unit motor feedforward voltage reference value U fe-jABCDEF for: ； Among them, u ob-jA 、u ob-jB 、u ob-jC 、u ob-jD 、u ob-jE 、u ob-jF They are the output reference value matrix U of the observer respectively. ob-jABCDEF The output reference values ​​of the observers for phases A, B, C, D, E, and F are: is the Hadamard product operation; the j-th unit motor phase voltage reference value U jABCDEF For U jABCDEF =U fe-jABCDEF +U ct-jABCDEF .

5. The fault-tolerant control method according to claim 4, characterized in that: A disturbance observer is designed, wherein the disturbance observer is designed as a sliding mode disturbance observer, an extended state observer or a reduced order observer.

6. The fault-tolerant control method according to claim 2, characterized in that: Applicable long stator segmented linear motor types include long stator segmented permanent magnet synchronous linear motors, long stator segmented asynchronous linear motors and other types of long stator segmented linear motors.

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