A long stator linear motor stator segment parallel power supply connection circuit and switch switching method thereof

Abstract

The invention provides a long-stator linear motor stator segment parallel power supply connection circuit and a switch switching method thereof. The motor stator segment is connected to an inverter through a switch composed of bidirectional thyristors, and the neutral points of the stator segments powered by the same inverter and powered on and off in sequence are connected; when the motor mover leaves a certain stator segment, a shutdown signal is sent to the bidirectional thyristors of each phase connected to the stator segment, and according to the sequence of zero-crossing shutdown of each phase current, the switches of each phase of the same phase connected to the next stator segment are opened in sequence at the same time; when one inverter supplies power to multiple motor stator segments or multiple inverters supply power to different motor stator segments respectively, the circuit and the switching method have the advantages that the inverter output current and the current in the feed-in cable are stable and without sudden changes during the stator segment power supply switching process, the current is stable and without distortion when the stator segment switch is turned off, and the current has no impact when the stator segment switch is closed.

Description

Technical Field

[0001] The invention relates to the field of motors, and in particular to a long-stator linear motor stator segment parallel power supply connection circuit and a switch switching method thereof. Background Art

[0002] Compared with rotary motors, linear motors have the advantages of simple structure, fast response speed and good tracking effect. They can be widely used in the field of linear drive, such as maglev trains, electromagnetic propulsion acceleration systems, vehicle high-speed collision test systems, ground test systems for parts of high-speed carrier systems such as aerospace, etc. Linear motors are usually divided into two categories: long armature linear motors and short armature linear motors. The representative application of short armature linear motors is medium and low-speed maglev trains. The direct current from the ground is transmitted to the vehicle through the catenary or the third rail. After the voltage, current and frequency are converted, the on-board armature is powered to drive the train. The typical application of long armature linear motors is high-speed maglev train systems, such as the German TR series maglev trains and the Japanese superconducting maglev trains. The long armature stator is arranged on the ground track. The alternating current output by the ground converter is fed into the armature winding through the switch. The total length of the ground armature is the length of the train line track. The long stator armature linear motor rotor (arranged at the bottom of the train) is much shorter than the stator armature fixed on the track. If the stator is fully energized, the effective area accounts for a very small proportion, the efficiency is very low, the power factor is very small, the power supply converter capacity is high and the cost is expensive. Usually, the long stator of the motor with the armature is segmented in application, and each segment is called a stator segment. The AC power output by the ground converter is fed into the stator segment through the feeder cable and the switching switch. The stator segment near the motor rotor is powered, and the other stator segments are not powered. The corresponding stator segment is switched to power according to the movement of the motor rotor. This can effectively improve the system efficiency and reduce the voltage and current levels of a single converter.

[0003] At present, there are two commonly used linear motor stator segment power supply methods: series power supply method and parallel power supply method. In the series power supply method, the armature windings of multiple stator segments arranged along the line are connected in series through switches and intermediate busbars, and then connected to the power supply converter; when the motor is driven to run, the switches connecting the stator segments are controlled to close or open in sequence, and the converter supplies power to the sequentially arranged stator segments in an alternating switching manner. Each time the motor is switched, the stator segment that the motor moves away from is powered off, and the stator segment where the motor moves or the stator segment that the motor moves are about to enter is powered on. This stator segment series power supply method requires that the voltage level of the converter system is very high, the withstand voltage level of the motor stator armature windings connected in series, the withstand voltage level of the switches, the withstand voltage level of the feeder cables, etc. are all very high. A large number of feeder cables and switches are used. When a stator segment or a group of switches connected in series fails, a string of stator segments must be shut down, and the fault tolerance is poor. The document "A Segmented Power Supply Strategy for Linear Motor Considering Current Zero Crossing" (Zhang Mingyuan [J] Journal of Naval University of Engineering, 2019, 31(04):11-16) applies segmented series power supply to linear motors in fast electromagnetic drive systems. Chinese invention patent CN110912493 A "Segmented Power Supply System for Induction Linear Motors" proposes an improved series power supply connection method, which reduces the number of switching switches by increasing the power supply busbar.

[0004] The parallel power supply method is that the armature windings of several linear motor stator segments arranged along the line are directly connected to the output end of the converter through switches, and the linear motor stator segments arranged in sequence are powered in an alternating manner. In the parallel power supply method, the voltage level of a single converter is low. Even if one stator segment fails to switch, the remaining stator segments can still operate normally, with high fault tolerance. Compared with series power supply, this power supply method has greater advantages in high-power and high-speed electromagnetic drive applications.

[0005] In the common parallel power supply mode, the neutral point of the stator winding is independent, and the switch is usually composed of high-voltage, high-current thyristors. The parallel power supply can adopt a zero-crossing shutdown strategy. However, when the current of one phase passes through zero and the phase is disconnected, the circuit changes, the waveform of the current of the remaining phases changes, the current is distorted, and it is no longer shut down in the original shutdown order, resulting in a longer shutdown time. When turned on, at least two phases must be turned on for the circuit loop to have current. It is impossible to turn on one phase circuit alone, the current overshoot increases, the current harmonics increase, and it is difficult to independently control the opening time of each phase circuit to reduce the current overshoot and reduce the large amount of harmonics generated during the switching process. At the same time, the output voltage of the converter and the allowable current of the motor winding are required to be high, and the system cost is relatively high. Summary of the invention

[0006] The purpose of the present invention is to propose a long-stator linear motor stator segment parallel power supply connection circuit and a switch switching method thereof, so as to solve the problems that when the stator segment parallel power supply linear motor is switched with the switch connected to the stator segment, the current is distorted in the process of turning off the previous stator segment switch, the current has impact in the process of closing the next stator segment switch, and the current is intermittent in the process of switching the stator segment power supply.

[0007] To achieve the above object, the present invention adopts the following scheme:

[0008] A long-stator linear motor stator segment parallel power supply connection circuit comprises a converter, a linear motor stator segment, a linear motor mover, a feed cable, a switch and a connecting cable. The long-stator linear motor stator armature is divided into a plurality of linear motor stator segments. Each linear motor stator segment is connected to a group of switches, and then connected to the output end of the converter for supplying power to the linear motor stator segment through the feed cable. When the linear motor stator segment is powered on, the switches of the linear motor stator segment where the linear motor mover is located and the linear motor stator segment that the linear motor mover is about to enter are closed, and the converter supplies power to these linear motor stator segments. The linear motor mover that has just left the linear motor stator segment is connected to the feed cable. The switching switches of the linear motor stator segments that have entered and the linear motor stator segments that have not entered are disconnected, and the converter does not power these linear motor stator segments; when the linear motor rotor length is less than or equal to the length of one linear motor stator segment, at least two adjacent linear motor stator segments are powered at the same time; when the linear motor rotor length is greater than one linear motor stator segment and less than or equal to two linear motor stator segments, at least three consecutive linear motor stator segments are powered at the same time; when the linear motor rotor length is greater than two linear motor stator segments and less than or equal to three linear motor stator segments, at least four consecutive linear motor stator segments are powered at the same time, and so on.

[0009] Furthermore, the long-stator linear motor is a long-stator-armature linear asynchronous motor or a long-stator-armature linear synchronous motor.

[0010] Furthermore, the long-stator linear motor is a motor with a single-side structure or a motor with a double-side structure.

[0011] Furthermore, the stator segments of the linear motors powered at the same time are connected to the same converter output terminal, or the stator segments of the multiple linear motors powered at the same time are connected to two or more different converter output terminals.

[0012] Furthermore, the neutral points of the stator segments that are powered by the same converter and powered on and off in sequence are connected, and the stator segments of the linear motor are numbered in sequence along the running direction, that is: when two adjacent stator segments of the linear motor are powered on at the same time, the neutral points of the 1#, 3#, 5#···(2m1+1)# stator segments connected in parallel to the same converter are connected together, and the neutral points of the 2#, 4#, 6#···(2m1+2)# stator segments connected in parallel to the same converter are connected together; when three consecutive stator segments are powered on at the same time, the neutral points of the 1#, 4#, 7#···(3m1+1)# stator segments connected in parallel to the same converter are connected together, and the neutral points of the 2#, 4#, 6#···(3m1+2)# stator segments connected in parallel to the same converter are connected together. +2)# stator segments neutral points are connected together, and the neutral points of 3#, 6#, 9#···(3m1+3)# stator segments connected in parallel to the same converter are connected together; in the case of simultaneous power supply of four consecutive stator segments, the neutral points of 1#, 5#, 9#···(4m1+1)# stator segments connected in parallel to the same converter are connected together, the neutral points of 2#, 6#, 10#···(4m1+2)# stator segments connected in parallel to the same converter are connected together, the neutral points of 3#, 7#, 11#···(4m1+3)# stator segments are connected together, the neutral points of 4#, 8#, 12#···(4m1+4)# stator segments connected in parallel to the same converter are connected together, and so on, where m1 is a natural number.

[0013] The present invention also provides a switching method for a parallel power supply connection circuit of a long-stator linear motor stator segment, which determines the linear motor stator segment to be powered according to the position of the linear motor mover. During the movement of the linear motor mover, the converter alternately powers the linear motor stator segments. When the linear motor mover leaves a certain linear motor stator segment, a shutdown signal is sent to the bidirectional thyristors of each phase connected to the linear motor stator segment. According to the order of each phase current zero-crossing shutdown, each phase switch connected to the next linear motor stator segment is opened in turn to complete the switching.

[0014] The beneficial effect of the present invention is as follows: the present invention proposes a circuit in which the neutral points of the stator segments of a linear motor connected in parallel under the same converter power supply line are connected, and a switching method is adopted in which the current of the upper stator segment is shut down when it passes through zero and the lower stator segment is opened at the same time, so as to reduce the problems of current distortion in the process of shutting down the upper stator segment during switching, current impact in the process of opening the lower stator segment, and current discontinuity during the entire switching process. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a structural diagram of the segmented power supply bilateral linear motor drive of the present invention;

[0016] Figure 2This is a schematic diagram of a circuit for connecting two adjacent linear motor stator segments to supply power in parallel using a single converter of the present invention;

[0017] Figure 3 This is a schematic diagram of a circuit for connecting two adjacent linear motor stator segments to supply power in parallel using two converters of the present invention;

[0018] Figure 4 This is a schematic diagram of a circuit for connecting three adjacent linear motor stator segments to supply power in parallel using a single converter of the present invention;

[0019] Figure 5 This is a schematic diagram of a circuit for connecting three converters of the present invention to supply power in parallel to three adjacent linear motor stator segments;

[0020] Figure 6 This is a schematic diagram of a circuit for connecting two adjacent stator segments of a dual three-phase linear motor in parallel to supply power to two converters of the present invention;

[0021] Figure 7 A schematic diagram of a current waveform of a single stator segment of the present invention;

[0022] Figure 8 This is the full-range current waveform diagram of the converter of the present invention.

[0023] In the figure, 1 is converter 1#, 2 is converter 2#, 3 is converter 3#, 10 is converter 1# output cable, 11 is converter 2# output cable, 20, 21, 22, 23, 24, 25...m is linear motor stator segments 1#, 2#, 3#, 4#, 5#, 6#...m1# are arranged in sequence, 100 is linear motor mover, 30, 31, 32, 33, 34, 35...n1 is feeder cables arranged in sequence, 40, 4 1, 42, 43, 44, 45...n2 are switches arranged in sequence, 50, 51, 52, 53, 54, 55...n3 are connecting cables arranged in sequence, 60 is the midpoint connecting cable 1 of the stator segment, 60' is the midpoint connecting cable 2 of the stator segment, 61 is the midpoint connecting cable 3 of the stator segment, 61' is the midpoint connecting cable 4 of the stator segment, 62 is the midpoint connecting cable 5 of the stator segment, and m, m1, n1, n2, n3 are natural numbers. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. The embodiments cited are only used to explain the present invention and do not limit the scope of the present invention.

[0025] like Figure 1The structure diagram of the segmented power supply bilateral linear motor drive is shown. Taking the linear motor mover 100 as an example, the length of which is less than one stator segment. Since the linear motor mover 100 is coupled with two stator segments at most at the same time, the two stator segments need to be energized at the same time to keep the coupling magnetic field between the linear motor stator segment and the linear motor mover 100 constant. It includes a converter 1#1, a converter 2#2, linear motor stator segments 1#, 2#, 3#, 4#, 5#, 6#...m1#20, 21, 22, 23...m arranged in sequence, a linear motor mover 100, feed cables 30, 31, 32, 33...n1 arranged in sequence, switches 40, 41, 42, 43...n2 arranged in sequence, and connecting cables 50, 51, 52, 53...n3 arranged in sequence. The stator armature of the long stator linear motor is divided into a plurality of linear motor stator segments 20, 21, 22, 23...m, each linear motor stator segment is connected to a set of switching switches, and then connected to the output terminal of the converter that supplies power to the linear motor stator segment through the corresponding converter 1# output cable 10 and converter 2# output cable 11, where m represents m1# of the linear motor stator segment. Preferably, the stator segments that are powered at the same time can be connected to the same converter output terminal, or the plurality of stator segments that are powered at the same time can be connected to two or more different converter output terminals. During the power supply operation, the switching switches of the stator segment where the linear motor mover is located and the stator segment that the linear motor mover is about to enter are closed, and the converter supplies power to these stator segments; the switching switches of the stator segment that the linear motor mover has just left and the stator segment that has not entered are disconnected, and the converter does not supply power to these stator segments. The number of stator segments that are powered is determined according to the length relationship between the linear motor mover and the length of a single stator segment. When the length of the linear motor rotor is less than or equal to the length of one stator segment, at least two adjacent stator segments are powered at the same time; when the length of the linear motor rotor is greater than one stator segment and less than or equal to two stator segments, at least three consecutive stator segments are powered at the same time; when the length of the linear motor rotor is greater than two stator segments and less than or equal to three stator segments, at least four consecutive stator segments are powered at the same time, and so on.

[0026] The stator segment to be powered is determined according to the position of the linear motor rotor. During the movement of the linear motor rotor, the converter alternately powers the stator segments. When the linear motor rotor leaves a certain stator segment, a shutdown signal is sent to the bidirectional thyristors of each phase connected to the stator segment. According to the order in which each phase current passes through zero and is shut down, each phase switch connected to the next stator segment is opened in turn to complete the switching.

[0027] It should be noted that the relationship between the length of the linear motor rotor and the length of the linear motor stator segment can be determined according to the output voltage, current, frequency of the linear motor system inverter and the running speed of the motor rotor.

[0028] It should be understood that when multiple converters are connected in parallel to supply power, the required number of converters is optional. For example, if the rotor length of the linear motor is greater than the length of one stator segment and less than the length of two stator segments, and the number of stator segments is three, three converters can be selected to power the three stator segments at the same time, or four converters can be selected to power the four stator segments at the same time. The selection is made based on actual needs, and the neutral point connection method between the stator segments remains unchanged.

[0029] Optionally, the parallel power supply connection circuit of the long stator linear motor stator segments is powered by a single converter, and all the stator segments are connected to one converter through a switching switch. When two adjacent stator segments are powered at the same time, the neutral points of the 1#, 3#, 5#···(2m1+1)# stator segments are connected together through a midpoint connecting cable, and the neutral points of the 2#, 4#, 6#···(2m1+2)# stator segments are connected together through a midpoint connecting cable; when three consecutive stator segments are powered at the same time, the neutral points of the 1#, 4#, 7#···(3m1+1)# stator segments are connected together through a midpoint connecting cable, the neutral points of the 2#, 5#, 8#···(3m1+2)# stator segments are connected together through a midpoint connecting cable, and the neutral points of the 3#, 6#, 9#···(3m1+3 )# stator segments are connected by midpoint connecting cables; when four consecutive stator segments are powered at the same time, the neutral points of 1#, 5#, 9#···(4m1+1)# stator segments are connected together by midpoint connecting cables, the neutral points of 2#, 6#, 10#···(4m1+2)# stator segments are connected together by midpoint connecting cables, the neutral points of 3#, 7#, 11#···(4m1+3)# stator segments are connected by midpoint connecting cables, the neutral points of 4#, 8#, 12#···(4m1+4)# stator segments are connected together by midpoint connecting cables, m1 is a natural number, and so on.

[0030] Optionally, the parallel power supply connection circuit of the long-stator linear motor stator segments is powered by multiple converters. When two adjacent stator segments are powered at the same time, two converters are used for power supply. The 1#, 3#, 5#···(2m1+1)# stator segments are all connected to converter 1# through their respective switching switches, and the neutral points of the 1#, 3#, 5#···(2m1+1)# stator segments are connected together through a midpoint connecting cable, and the 2#, 4#, 6#···(2m1+2)# stator segments are all connected to converter 2# through their respective switching switches, and the neutral points of the 2#, 4#, 6#···(2m1+2)# stator segments are connected through the midpoint. Cables are connected together; when three consecutive stator segments are powered at the same time, three converters are used for power supply, and 1#, 4#, 7#···(3m1+1)# stator segments are all connected to converter 1#1 through their respective switching switches, and the neutral points of the 1#, 4#, 7#···(3m1+1)# stator segments are connected together through midpoint connecting cables, and 2#, 5#, 8#···(3m1+2)# stator segments are all connected to converter 2#2 through their respective switching switches, and the neutral points of the 2#, 5#, 8#···(3m1+2)# stator segments are connected together through midpoint connecting cables, and 3#, 6#, 9#···(3m1+3 )# stator segments are all connected to converter 3# through their respective switching switches, and the neutral points of the 3#, 6#, 9#···(3m1+3)# stator segments are connected through a midpoint connecting cable; when four consecutive stator segments are powered at the same time, four converters are used for power supply, and the 1#, 5#, 9#···(4m1+1)# stator segments are all connected to converter 1# through their respective switching switches, and the neutral points of the 1#, 5#, 9#···(4m1+1)# stator segments are connected together through a midpoint connecting cable, and the 2#, 6#, 10#···(4m1+2)# stator segments are all connected to converter 2# through their respective switching switches, and the The neutral points of 2#, 6#, 10#···(4m1+2)# stator segments are connected together through a midpoint connecting cable, 3#, 7#, 11#···(4m1+3)# stator segments are all connected to converter 3# through their respective switching switches, and the neutral points of 3#, 7#, 11#···(4m1+3)# stator segments are connected through a midpoint connecting cable, 4#, 8#, 12#···(4m1+4)# stator segments are all connected to converter 4# through their respective switching switches, and the neutral points of 4#, 8#, 12#···(4m1+4)# stator segments are connected together through a midpoint connecting cable, m1 is a natural number, and so on.

[0031] Figure 2The present invention is a schematic diagram of a circuit for connecting two adjacent linear motor stator segments in parallel with a single converter. The linear motor stator segments 20, 21, 22, 23 ... m are connected to respective switches 40, 41, 42, 43 ... n2 through connecting cables 50, 51, 52, 53 ... n3, and the switching switches 40, 41, 42, 43 ... n2 are all connected to the output end of a converter 1#1 through feeding cables 30, 31, 32, 33 ... n1. In the case where two adjacent linear motor stator segments are powered at the same time, the neutral points of the 1#, 3#, 5#... (2m1+1)# stator segments are connected together through the midpoint connecting cable 1 60 of the stator segment, and the neutral points of the 2#, 4#, 6#... (2m1+2)# stator segments are connected together through the midpoint connecting cable 3 61 of the stator segment, and m, m1, n1, n2 are natural numbers.

[0032] Figure 3 FIG. 1 is a schematic diagram of a circuit for connecting two adjacent linear motor stator segments to power them in parallel using two converters of the present invention. For a multi-converter power supply system, when two adjacent stator segments are powered simultaneously, two converters 1#1 and 2#2 are used for power supply. The 1#, 3#, 5#...(2m1+1)# stator segments are connected to their respective switching switches 40, 42,...(n2-1) via connecting cables 50, 52,...(n3-1). The switching switches 40, 42,...(n2-1) are connected to the respective switching switches 40, 42,...(n2-1) via feeding cables 30, 3 2, ...(n1-1) are all connected to converter 1#1, and the neutral points of the 1#, 3#, 5#···(2m1+1)# stator segments are connected together through the midpoint connecting cable 160 of the stator segment; the 2#, 4#, 6#···(2m1+2)# stator segments are connected to their respective switching switches 41, 43, ...n2 through connecting cables 51, 53, ...n3, the switching switches 41, 43, ...n2 are all connected to converter #2 2 through feeding cables 31, 33, ...n1, and the neutral points of the 2#, 4#, 6#···(2m1+2)# stator segments are connected together through the midpoint connecting cable 361 of the stator segment, m1, n1, n2, n3 are natural numbers.

[0033] Figure 4The present invention is a schematic diagram of a circuit for connecting three adjacent linear motor stator segments in parallel with a single converter. The linear motor stator segments 20, 21, 22, 23 ... m are connected to respective switches 40, 41, 42, 43 ... n2 via connecting cables 50, 51, 52, 53 ... n3, and the switches 40, 41, 42, 43 ... n2 are all connected to the output end of a converter 1#1 via feeding cables 30, 31, 32, 33 ... n1. When three consecutive stator segments are powered at the same time, the neutral points of 1#, 4#, 7#···(3m1+1)# stator segments are connected together through the midpoint connecting cable 1 60 of the stator segment, the neutral points of 2#, 5#, 8#···(3m1+2)# stator segments are connected together through the midpoint connecting cable 3 61 of the stator segment, and the neutral points of 3#, 6#, 9#···(3m1+3)# stator segments are connected through the midpoint connecting cable 5 62 of the stator segment, where m, m1, n1, and n2 are natural numbers, and so on.

[0034] Figure 5 The present invention is a schematic diagram of the circuit connection of three converters for parallel power supply of three adjacent linear motor stator segments. When three consecutive stator segments are powered simultaneously and three converters are used for power supply, the 1#, 4#, 7#···(3m1+1)# stator segments are connected to their respective switching switches 40, 43, ... (n2-2) through connecting cables 50, 53, ... n3-2, and the switching switches 40, 43, ... (n2-2) are all connected to the converter 1#1 through feeding cables 30, 33, ... (n1-2), and the neutral points of the 1#, 4#, 7#···(3m1+1)# stator segments are connected to the stator segments 1#1 through the stator segments 1#2. The midpoint connecting cable 160 is connected together; the 2#, 5#, 8#···(3m1+2)# stator segments are connected to their respective switches 41, 44, ... (n2-1) through connecting cables 51, 54, ... (n3-1); the switches 41, 44, ... (n2-1) are all connected to the converter 2#2 through feeding cables 31, 34, ... (n1-1); and the neutral points of the 2#, 5#, 8#···(3m1+2)# stator segments are connected through the midpoint connecting cable 31, 34, ... (n1-1). 61 are connected together; 3#, 6#, 9#···(3m1+3)# stator segments are connected to respective switches 42, 45, ...n2 through connecting cables 52, 55, ...n3, and the switches 42, 45, ...n25 are all connected to converter 3# through feeding cables 32, 35, ...n1, and the neutral points of the 3#, 6#, 9#···(3m1+3)# stator segments are connected through the midpoint connecting cable 5 62 of the stator segments, where m, m1, n1, n2, and n3 are natural numbers.

[0035] Optionally, in some embodiments, the linear motor may be a multi-phase motor, such as a dual three-phase motor, and the neutral point connection circuit may be Figure 6 As shown, the neutral point connection mode of the stator segment winding of the linear motor in the parallel power supply connection circuit of two converters is that converter 1# supplies power to 1#, 3#, 5#···(2m1+1)# stator segments 20, 22, 24...(m-1), and the double neutral points of 1#, 3#, 5#···(2m1+1)# stator segments 20, 22, 24...(m-1) are connected respectively through the midpoint connecting cables 1, 2 60, 60' of the stator segments; converter 2# supplies power to 2#, 4#, 6#···(2m1+2)# stator segments 21, 23, 25...m, and the double neutral points of 2#, 4#, 6#···(2m1+2)# stator segments 21, 23, 25...m are connected respectively through the midpoint connecting cables 3, 461, 61' of the stator segments, and m and m1 are natural numbers.

[0036] Optionally, in some embodiments, the linear motor can be a long stator armature linear asynchronous motor, a long stator armature linear synchronous motor, or other forms of long stator armature linear motors. The long stator linear motor can be a single-sided structure motor or a double-sided structure motor.

[0037] Figure 7 It is the current waveform of a single stator segment. For the current of a single stator segment, when it is turned on, each phase is turned on in sequence according to the current phase sequence, and there is no current impact; when it is turned off, each phase is turned off in sequence according to the current phase sequence, and there is no current distortion.

[0038] Figure 8 The full-range current waveform of the converter. For the full-range current of the converter, the current is continuous during the switching process, the current has no impact, and the current change trend is not affected. The linear motor stator segment parallel power supply connection circuit ensures that the switching of segmented stator segments in the long-stator linear motor segment parallel power supply system has no effect on the current of the converter; for motor control, the current is continuous, making the motor control simpler.

[0039] 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 long-stator linear motor stator segment parallel power supply connection circuit, which includes a converter, a linear motor stator segment, a linear motor mover, a feed cable, a switch and a connecting cable, the long-stator linear motor stator armature is divided into a plurality of linear motor stator segments, each linear motor stator segment is connected to a group of switches, and then connected to the converter output end for supplying power to the linear motor stator segment through the feed cable; when the linear motor stator segment is powered on, the switch of the linear motor stator segment where the linear motor mover is located and the linear motor stator segment where the linear motor mover is about to enter is closed, and the converter supplies power to these linear motor stator segments; the switch of the linear motor stator segment where the linear motor mover has just left and the linear motor stator segment that has not entered is disconnected, and the converter does not supply power to these linear motor stator segments; It is characterized in that When the length of the linear motor rotor is less than or equal to the length of one linear motor stator segment, at least two adjacent linear motor stator segments are powered at the same time; when the length of the linear motor rotor is greater than one linear motor stator segment and less than or equal to two linear motor stator segments, at least three consecutive linear motor stator segments are powered at the same time; when the length of the linear motor rotor is greater than two linear motor stator segments and less than or equal to three linear motor stator segments, at least four consecutive linear motor stator segments are powered at the same time, and so on; The neutral points of the stator segments that are powered by the same converter and powered on and off in sequence are connected. That is, when two adjacent linear motor stator segments are powered on at the same time, the neutral points of the 1#, 3#, 5#···(2m1+1)# stator segments connected in parallel to the same converter are connected together, and the neutral points of the 2#, 4#, 6#···(2m1+2)# stator segments connected in parallel to the same converter are connected together. When three consecutive stator segments are powered on at the same time, the neutral points of the 1#, 4#, 7#···(3m1+1)# stator segments connected in parallel to the same converter are connected together, and the neutral points of the 2#, 5#, 8#···(3m1+2)# stator segments connected in parallel to the same converter are connected together. The neutral points of the 3#, 6#, 9#···(3m1+3)# stator segments connected in parallel to the same converter are connected together; when four consecutive stator segments are powered at the same time, the neutral points of the 1#, 5#, 9#···(4m1+1)# stator segments connected in parallel to the same converter are connected together, the neutral points of the 2#, 6#, 10#···(4m1+2)# stator segments connected in parallel to the same converter are connected together, the neutral points of the 3#, 7#, 11#···(4m1+3)# stator segments connected in parallel to the same converter are connected together, the neutral points of the 4#, 8#, 12#···(4m1+4)# stator segments connected in parallel to the same converter are connected together, and so on. m1 is a natural number.

2. The long stator linear motor stator segment parallel power supply connection circuit according to claim 1, characterized in that: The long-stator linear motor is a long-stator-armature linear asynchronous motor or a long-stator-armature linear synchronous motor.

3. The long stator linear motor stator segment parallel power supply connection circuit according to claim 1, characterized in that: The long-stator linear motor is a motor with a single-side structure or a motor with a double-side structure.

4. The long stator linear motor stator segment parallel power supply connection circuit according to claim 1, characterized in that: The stator segments of the linear motors powered simultaneously or alternately are connected to the same converter output terminal, or the stator segments of the linear motors powered simultaneously or alternately are connected to multiple different converter output terminals.

5. The method for switching the stator segment parallel power supply connection circuit of the long stator linear motor according to any one of claims 1 to 4, characterized in that: The linear motor stator segment to be powered is determined according to the position of the linear motor rotor. During the movement of the linear motor rotor, the converter alternately powers the linear motor stator segments. When the linear motor rotor leaves a certain linear motor stator segment, a shutdown signal is sent to the bidirectional thyristors of each phase connected to the linear motor stator segment. According to the order in which each phase current passes through zero and is shut down, each phase switch connected to the next linear motor stator segment is opened in turn to complete the switching.

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