Method for operating a linear motor arrangement and linear motor arrangement

Abstract

Method for operating a linear motor arrangement (1), comprising the steps of: controlled introduction of electrical energy to a first stator segment (10) equipped with magnetic coils for the controlled provision of a magnetic field to a permanent magnet arrangement (8) of a transport means (3) for generating drive forces, regulated introduction of electrical energy to a second stator segment (20) equipped with a measuring device (9) for determining a position of a transport means (3) and with magnetic coils for the controlled provision of a magnetic field to the transport means (3), wherein a control device (6) upon a transition of the transport means (3) from the first stator segment (10) to the second stator segment (20) and / or upon a transition of the transport means (3) from the second to the first stator segment (20, 10),temporarily switching the second stator segment (20) from the regulated state to a controlled state, and wherein the control device (6) activates an algorithm for determining the position of the transport means (3) for switching between the controlled introduction of electrical energy and the controlled introduction of electrical energy into the second stator segment (20) and, within a predeterminable time period comprising at least two control cycles of the control device (6), reduces a difference between a desired position value for the transport means (3) and an actual position value for the transport means (3) such that the actual position value at the end of the time period corresponds at least substantially to the desired position value.

Description

[0001] The invention relates to a method for operating a linear motor arrangement. Furthermore, the invention relates to a linear motor arrangement.

[0002] According to a prior art known to the applicant but not documented in print, a plurality of stator segments, each equipped with one or more individually controllable magnetic coils and arranged along a movement path, are controlled by means of a control device which is coupled to position measuring systems assigned to each of the stator segments and which provides electrical energy to the respective stator segments in a controlled manner depending on a position of the at least one transport means.

[0003] DE 43 05 274 A1 discloses a long-stator linear motor with a relatively short secondary section and a stationary primary section composed of several segments. To achieve a high degree of motion uniformity without complex post-processing of the stator windings, it is proposed to control the supply source depending on the known position of the secondary section relative to the primary section in such a way that the current per unit area of the primary section is increased when and as long as the secondary section is located in the region of a transition point between two adjacent segments of the primary section. The increase in the current per unit area is dimensioned such that the reduction in the current per unit area caused by the lower winding density at the ends of the segments is substantially compensated.

[0004] DE 690 18 108 T2 discloses a servo circuit for controlling the positioning of a servo object under servo control to a target position by changing the speed control to a position control in the vicinity of the target position, comprising: a speed detection device for detecting the actual speed based on a position signal transmitted from the servo object, a speed error detection device for generating a speed error signal between a target speed and the actual speed, a position error detection device for generating a position error signal based on the position signal, a switching device for switching the connection of the servo object to the speed error detection device or the position error detection device and for supplying a control current to the servo object,a control current detection device for detecting the control current and generating a current measurement signal, and a main processing unit for generating a coarse / fine switching signal for the switching device and for controlling the servo object from coarse control to position control, and for supplying the reference target speed signal to the speed error detection circuit, wherein the main processing device further comprises a gain adjustment signal generation unit for generating a target speed gain adjustment signal, a current measurement gain adjustment signal, and a speed gain adjustment signal, and for adjusting the detection gains of each of the gain adjustment signals in the acceleration control phase so as to increase in accordance with the decrease in the remaining search amount,and that the main processing unit further supplies the target speed gain setting signal to the speed error detection circuit and supplies the current measurement gain setting signal and the tempo gain setting signal to the speed detection device, wherein the speed detection device further includes a speed detection gain setting unit for performing control to vary the detection gains of the speed and current measurement gain setting signals.

[0005] DE 10 2008 008 602 A1 discloses a transfer device for workpiece carriers with multiple segments, each of which has a control unit controlling a linear motor. During the transfer phase of the workpiece carrier from a first segment to an adjacent segment, synchronization of the linear motors is no longer effected by control commands from a central control device. Instead, the control unit of the first segment establishes itself as the master and subordinates the control unit of the adjacent segment to the slave. A position measuring device enables the master control unit to perform speed control for the workpiece carrier. The control unit receives information about the commutation angle and the actual force value and can thus issue the control commands to the associated linear motor for the purpose of control.

[0006] The object of the invention is to provide a method for operating a linear motor arrangement and a linear motor arrangement which, with a simplified design, has a similar performance to the linear motor arrangement known from the prior art.

[0007] This object is achieved according to a first aspect of the invention for a method for operating a linear motor arrangement with the features of claim 1.

[0008] The following steps are provided here: controlled introduction of electrical energy to a first stator segment equipped with magnetic coils for the controlled provision of a magnetic field to a permanent magnet arrangement of a means of transport for generating drive forces, controlled introduction of electrical energy to a second stator segment equipped with a measuring device for determining a position of a means of transport and with magnetic coils for the controlled provision of a magnetic field to the means of transport, wherein a control device carries out a temporary switch of the second stator segment from the controlled state to a controlled state when the means of transport transitions from the first stator segment to the second stator segment and / or when the means of transport transitions from the second to the first stator segment, in particular depending on the position of the means of transport along a movement path.

[0009] The first and second stator segments can be arranged in any order along the movement path, and one or more transport devices can be moved simultaneously along the movement path on the stator segments under the supervision of the control device. For example, the second stator segments can be provided in those sections of the movement path where exact knowledge of the position of the respective transport device and / or highly efficient utilization of the magnetic field by the transport device is required. Exact knowledge of the position of the transport device may be necessary, for example, if the transport device is transporting a container that is to be filled with a product at a filling station.This may require, for example, deceleration of the transport means to a standstill while precisely maintaining a predefined filling position and / or, after completion of the filling process, smooth acceleration to a predefined target speed. Particularly efficient utilization of the magnetic field emitted by the stator segments through the appropriate provision of electrical energy is particularly important when increased resistance to movement of the transport means is to be expected. In contrast, first stator segments, which only provide for controlled movement of the transport means along the movement path, can be provided along those sections of the movement path where, for example, uniform movement of the transport means is sufficient without exact knowledge of the respective transport means' position.The section-by-section, controlled operation of the respective stator segments significantly simplifies the linear motor arrangement, as a position measuring system can be omitted in the first stator segments. Furthermore, eliminating the need for closed-loop control of all stator segments along the movement path also simplifies the control system, as fewer position signals from the position measuring systems need to be processed. Furthermore, looping transport means onto or off the movement path along the first, only controlled stator segments is easier to implement than with closed-loop controlled stator segments, as the respective transport means do not need to be logged on or off with the corresponding control algorithm of the control system.

[0010] By switching the second stator segment from a regulated operating mode to a controlled operating mode when a means of transport approaches a transition between a first and a second stator segment, the characteristics of the magnetic fields generated by the respective stator segments, which move along the path of movement, are facilitated. The control device can temporarily deactivate the currently running control algorithm for the corresponding stator segment, thus eliminating the need for complex adjustments to the control algorithm, particularly for adjusting the control frequency and phase angle of the control signal for the second stator segment to the control signal of the first stator segment.This allows the control device to ensure, with manageable effort, an at least virtually jerk-free transition of the respective means of transport from a generally controlled and only occasionally controlled section of the trajectory to a section of the trajectory that is always controlled. Furthermore, the control device can ensure, with manageable effort, an at least virtually jerk-free transition of the respective means of transport from a section of the trajectory that is always controlled to a generally controlled and only occasionally controlled section of the trajectory.

[0011] It is expedient if the control device, during the controlled introduction of electrical energy to the second stator segment, provides an alternating electrical voltage for the magnetic coils such that, along a movement path of the transport means, a phase angle of 90 degrees is established between a portion of the active current supplied to the second stator segment and a position of a magnetic center of action of the permanent magnet arrangement of the transport means. At such a phase angle, the maximum resulting magnetic force is established between the magnetic wave emitted by the magnetic coils arranged in the stator segment and supplied with electrical energy and the permanent magnet arrangement formed on the transport means.The magnetic center of action of the permanent magnet arrangement can be seen as analogous to the center of mass of a mass and indicates the location where the magnetic fields of the permanent magnet arrangement, preferably formed by bar magnets arranged in a row with opposite polarity, can be combined into a single magnetic pole. A phase angle of 90 degrees between the active current component and the magnetic center of action is present, for example, when the stator segment is supplied with a sinusoidal electric current and the position of the magnetic center of action along the trajectory is phase-shifted by a quarter of the resulting wavelength (λ / 4) for the magnetic wave.

[0012] In a further development of the method, it is provided that the control device, during the controlled introduction of electrical energy to the first stator segment, provides an alternating current to the magnetic coils with a predeterminable frequency dependent on a target speed of the transport means and / or regulates a nominal current for the magnetic coils. During the controlled introduction of electrical energy, in which the control device has no knowledge of the actual position of the transport means due to the lack of a position measuring system in the first stator segment, the speed of the transport means is adjusted depending on the speed of movement of the magnetic shaft, which is caused by the excitation of the first stator segment with alternating electrical current. By influencing the frequency of the alternating current, the speed of the transport means can thus be adjusted.In practice, it can be assumed that the magnetic center of action during controlled operation of the stator segment assumes a phase angle of approximately 90 degrees relative to the active current component at the stator segment that arises when the stator segment is subjected to electrical voltage, and is thus at least substantially in phase with the reactive current component. Preferably, the control device regulates the electrical current flowing through the magnetic coils for the first stator segment in order to avoid inhomogeneities in the magnetic waves that could lead to undesirable speed fluctuations for the means of transport.

[0013] In an advantageous embodiment of the invention, when the means of transport approaches a transition between a second and a first stator segment, the control device changes the phase angle between the active current component provided to the second stator segment and the position of the magnetic active center of the permanent magnet arrangement of the means of transport by 90 degrees in order to switch between the regulated introduction of electrical energy and the controlled introduction of electrical energy into the second stator segment.By adjusting the phase angle, a position for the magnetic center of action relative to the magnetic shaft provided by the second stator segment is achieved before switching to controlled operation of the second stator segment, which at least nearly corresponds to the position of the magnetic center of action relative to the magnetic shaft after switching to controlled operation of the second stator segment. This ensures that when switching between controlled and controlled operation for the second stator segment, no step function for the traveling magnetic field occurs during the switchover, and thus no undesirable jerky acceleration or deceleration of the transport device.

[0014] For a movement of the transport means across the transition between the second and first stator segments, the control device preferably performs frequency- and phase-matched control of the first and second stator segments. To ensure phase-matched control of the two stator segments, a distance between the last magnetic coil of the preceding stator segment along the movement path and the first magnetic coil of the following stator segment along the movement path must be included in the calculation of the respective control voltages to ensure that the two magnetic traveling fields of the stator segments overlap at the transition between the stator segments.

[0015] It is advantageous if, after changing the phase angle by 90 degrees to implement the switchover to the controlled introduction of electrical energy to the second stator segment, the control device deactivates a control algorithm for controlling the actual position value of the transport device and / or an algorithm for determining the position of the transport device. This ensures, for example, that no control deviations are stored in the control algorithm during the phase of controlled activation of the second stator segment, which could initially lead to undesirable, for example, erratic, controller behavior when the control algorithm is used again.

[0016] According to the invention, the control device activates an algorithm for determining the position of the transport means for switching between the controlled introduction of electrical energy and the regulated introduction of electrical energy into the second stator segment and, within a predeterminable time period comprising at least two control cycles of the control device, reduces a difference between a desired position value for the transport means and an actual position value for the transport means such that the actual position value at the end of the time period at least substantially corresponds to the desired position value. The activation of the algorithm for determining the position, which preferably occurs in a first step during the switchover from controlled to regulated operation, serves to determine an actual position value of the transport means.The actual position value can, for example, be an actual phase angle between the magnetic active center and the active current component supplied to the second stator segment during controlled operation. The difference between the actual position value and a predefined position setpoint, for example, a phase angle of 90 degrees, is then determined. To prevent jerky movement of the transport device when switching to controlled operation of the second stator segment, the compensation of the determined difference between the actual position value and the position setpoint is distributed over at least two control cycles of the control device.When specifying the number of control cycles within which an at least almost complete adjustment of the actual position value to the position setpoint is to take place, the mass of the transport means, the maximum electrical load capacity of the magnetic coils and the flux density of the permanent magnet arrangement as well as the frequency of the control must be taken into account in order to prevent undesirable jerky movements of the transport means during the switching process.

[0017] It is expedient if, in order to reduce the difference between the position setpoint for the means of transport and the position actual value for the means of transport, at the start of the switchover between the controlled and the regulated introduction of electrical energy into the second stator segment, the control device resets at least one integral component of at least one control algorithm for controlling the position and speed of the means of transport to a predeterminable value, in particular zero, and / or the control device, starting from a reduced current limiting threshold, raises the current limiting threshold for the second stator segment over several controller cycles.The integral component of the control algorithm sums the control deviations determined within successive control cycles by calculating the difference between the actual position value and the position setpoint. This results in at least almost complete equalization between the actual position value and the position setpoint within an integral-action time dependent on the properties of the linear motor arrangement. In addition or alternatively, to prevent jerky movements of the transport device when switching from open-loop control to closed-loop control of the stator segment, a current limiting threshold for the magnetic coils in the stator segment can be initially lowered, particularly at the time of switchover, and then raised again over several control cycles, thus preventing the buildup of an excessive magnetic potential between the stator segment and the permanent magnet arrangement of the transport device at the beginning of the control process.

[0018] According to a second aspect of the invention, the object of the invention is achieved with a linear motor arrangement according to claim 9. The control device can preferably be designed as a programmable logic controller (PLC), whose control signals are forwarded to wired or wirelessly coupled control devices designed to provide electrical energy to the stator segments. With such a linear motor arrangement, one or more transport means can be moved along the movement path determined by the stator segments at different speeds in controlled and regulated operation.

[0019] It is advantageous if a stator segment comprises several magnetic coils, preferably arranged at equal spacing along the movement path. Adjacent magnetic coils are designed such that, when controlled jointly by a control unit, they provide opposing magnetic fields. By mechanically and electrically combining several magnetic coils in one stator segment, both a cost-effective mechanical design and simple electrical control of the respective stator segment can be achieved.

[0020] An advantageous embodiment of the invention is shown in the drawing.

[0021] Here the Fig. 1 to 4 a transition of a means of transport from a controlled stator segment to a fundamentally regulated and briefly controlled stator segment.

[0022] The Fig. 5 to 8 show a transition of a means of transport from a stator segment that is basically operated in a regulated and briefly controlled manner to a stator segment that is operated in a controlled manner.

[0023] In the Fig. 1 shows a section of a linear motor arrangement 1 which, by way of example, comprises a plurality of stator segments 10, 20 arranged in a row along a movement path 2, at least one transport means 3 movable relative to the stator segments 10, 20 along the movement path 2, as well as control devices 4, 5 assigned to the stator segments 10, 20 and designed to provide electrical energy, and a control device 6 for providing control signals to the control devices 4, 5.

[0024] The stator segments 10, 20 each comprise a plurality of magnetic coils (not shown) arranged next to one another along the movement path, in particular adjacent to one another, which are electrically and mechanically accommodated in the respective stator segment 10, 20. The magnetic coils are designed, for example, such that winding planes of windings of the magnetic coils are each parallel to a section of the movement path 2 and perpendicular to a representation plane of the Fig. 1 to 8. The magnetic coils are further electrically connected to one another in such a way that all of the magnetic coils of a stator segment 10, 20 can be supplied with electrical energy, in particular with a common electrical voltage, at the same time, and that adjacently arranged magnetic coils emit opposing magnetic fields. This can be achieved, for example, by opposing electrical polarity of adjacent magnetic coils or by winding the turns of the adjacent magnetic coils in opposite directions. By applying an alternating electrical current to the magnetic coils of the respective stator segments 10, 20, a traveling magnetic field can be generated which moves in the direction of the movement path 2 and which, through interaction with a permanent magnet arrangement 8 on the transport means 3, provides a propulsive force to the transport means 3.The speed of movement of the transport means 3 is determined by a frequency of the magnetic traveling field.

[0025] The permanent magnet arrangement 8 on the means of transport 3 comprises, for example, four cuboid bar magnets 9, the largest extent of which is normal to the plane of representation of the Fig. 1 to 8 and which are arranged in a row along the movement path 2. The bar magnets 9 are arranged in such a way that adjacent bar magnets 9 have opposite polarities. Thus, Fig. 1 to 8, the visible end faces of the bar magnets 9 each exhibit opposing magnetic field lines. As an example, a magnetic center of action 11 is drawn in the geometric center of the permanent magnet arrangement 9, symbolizing the point at which the magnetic field lines of the bar magnets 9 can be modeled together. This magnetic center of action 11 is taken into account in particular when determining the phase angle for the electrical application to the stator segments 10, 20.

[0026] The control device 6 is designed for the controlled provision of electrical energy to the first stator segment 10. Preferably, the first stator segment 10 is supplied with an alternating electrical voltage whose frequency can be specified and adapted to different operating conditions for the first stator segment 10. The amplitude of the alternating electrical voltage, which determines the current flow through the magnetic coils of the first stator segment 10, can also be adjusted using a predeterminable value. However, by way of example, a control of the amplitude of the alternating electrical voltage is provided for the first stator segment 10, in particular based on monitoring the coil current through the magnetic coils.

[0027] The second stator segment 20 differs from the first stator segment 10 by a position measuring system 9, which is electrically connected to the control device 6 and generates a position signal depending on the position of the transport means 3 along the movement path 2. By way of example, the position measuring system 9 is designed as a magnetostrictive position measuring system, which is designed to interact with a permanent magnet (not shown) attached to the transport means 3 and in which a signal propagation time through the position measuring system 9 is used as a measure of the position of the transport means 3.

[0028] With the aid of the position measuring system 9, the control device 6 can regulate the position of the transport means 3 along that section of the movement path 2 that extends along the second stator segment 20. In this control, the control device 6 uses a difference between an actual position value, i.e., an actual position of the transport means 3 along the movement path 2, and a position setpoint, i.e., an expected position of the transport means 3 at a given time, as a control deviation, which is to be minimized over one or more control cycles by means of the control algorithm running in the control device 6.

[0029] Preferably, the control algorithm is designed such that the position of the transport means 3, in particular the position of the magnetic active center 11 of the transport means 3, is located relative to the magnetic traveling wave provided by the second stator segment such that a phase angle of 90 degrees is always maintained between the electrical active current through the magnetic coils and the magnetic active center 11 of the transport means 3. This is described in more detail below. Fig. 5 is symbolized by the fact that a distance between an upper peak of the electric current for the second stator segment 20, represented by an example sine wave, and the magnetic active center 11 of the transport means 3 corresponds to a quarter (λ / 4) of the wavelength (λ) of the magnetic traveling wave. The active current component (not shown) is in phase with the voltage curve at the magnetic coils, while the reactive current component (not shown) has a phase angle of 90 degrees relative to the voltage and the active current component.

[0030] In the Fig. 1 to 4, the following procedure can be provided. The transport means 3 moves along the movement path 2 due to the magnetic traveling wave emitted by the first stator segment 10 by applying electrical energy to the magnetic coils. Assuming a vanishing resistance to movement for the movement of the transport means 3 along the stator segment 10, a phase angle between the electrical voltage, shown as an example as a sine wave and provided by the control unit 4 to the first stator segment, and the magnetic center of action 11 of the transport means 3 is only a few degrees or ideally 0 percent of the wavelength (λ) of the magnetic traveling wave, as shown in the Fig. 1. From the Fig. 1 also shows that the second stator segment 20 does not have to be subjected to an electrical voltage if the transport means 3 is sufficiently far away from a transition between the first and second stator segments 10, 20.

[0031] As the transport means 3 approaches the transition between the first and second stator segments 10, 20, the second stator segment 20 is initially activated by the control device 6 in a controlled operating mode. The control device 6, with the aid of the control unit 5, initially applies electrical voltage to the second stator segment 20 in such a way that, for example, a current waveform with the same frequency, phase, and amplitude is established at the second stator segment 20. This is intended to ensure that the magnetic traveling waves of the two stator segments 10, 20 are congruent. This allows the transport means 3 to pass smoothly through the transition between the first and second stator segments 10, 20.

[0032] However, since the second stator segment 20 is fundamentally designed for controlled operation, and such controlled operation is required for some movement sequences, for example, to control a specific position along the movement path 2 and / or to maintain a predeterminable movement speed, a switching of the second stator segment 20 from controlled to controlled operation is provided. For this purpose, in a first step, the control device 6 activates the position measuring system 7. Based on a position signal provided by the position measuring system 7, the position of the transport means 3, in particular the position of the magnetic center of action 11, along the second stator segment 20 can then be determined with the aid of an algorithm running in the control device 6.Subsequently, a control algorithm running in the control device 6 is activated, which determines a control deviation based on the difference between the actual position value for the transport means 3 and the desired position value for the transport means 3. This control deviation is then minimized by the control device 6 appropriately influencing the frequency and amplitude of the alternating electrical current to be provided to the magnetic coils of the second stator segment 20 within a predeterminable period of time, for example, within several control cycles. As a result of minimizing the control deviation, the previously described state is sought, in which a phase angle of 90 degrees is maintained between the active current component through the magnetic coils of the second stator segment 20 and the magnetic active center 11 of the permanent magnet arrangement 8.

[0033] To avoid jerky movements of the transport means 3, it can be provided, for example, that an integral component in the control algorithm is set to a predetermined value, in particular to zero, at the time of switching between open-loop and closed-loop operation of the second stator segment 20. This can ensure that the control algorithm requires several control cycles to adjust the actual position value to the desired position value, thus avoiding a sudden change in the movement state of the transport means 3.

[0034] Additionally or alternatively, the amplitude of the electric current supplied to the magnetic coils of the second stator segment 20 can be limited to a predeterminable first value when switching from controlled to regulated operation of the second stator segment 20 and then increased to a second, higher value within a predeterminable number of control cycles. This limits the active current and thus the magnetic force acting on the transport means 3. This time-dependent increase in the current limit threshold for the magnetic coils achieves a progressive increase in the magnetic force over a predeterminable period of time, allowing a smooth transition for the movement of the transport means 3 from the controlled state to the regulated state.

[0035] Additionally or alternatively, it can also be provided that the control algorithm, at the time of switching from the controlled to the controlled operation of the second stator segment 20, carries out a calculation of the necessary acceleration or deceleration which is necessary to achieve the desired position setpoint and, based on a predeterminable maximum acceleration for the transport means 3, sets the number of control cycles and / or the increase in the current limiting threshold in such a way that the maximum acceleration is not exceeded.

[0036] In the Fig. 5 to 8, the transition of the transport means 3 from the second, controlled stator segment 20 to the first, controlled stator segment 10, the specification of the phase angle of 90 degrees between the active current component for the magnetic coils and the magnetic active center 11 of the permanent magnet arrangement 8 is first modified in such a way that a phase angle of 180 degrees or 0 degrees is achieved, as shown in the Fig. 6. Thus, the transport means 3 is moved at least substantially in phase with the reactive current component of the magnetic coils of the second stator segment 20.

[0037] The control device 6 then begins controlling the first stator segment 10. In particular, the frequency and / or phase and / or amplitude of the electrical current applied to the first stator segment 10 are selected such that the two magnetic traveling waves of the adjacent stator segments 20, 10 are identical in frequency and / or phase and / or amplitude and thus coincide. In a subsequent step, the control device 6 deactivates the control algorithm and the algorithm for determining the position of the transport means 3 using the position measuring system 9, thereby completing the switchover from closed-loop operation to open-loop operation of the second stator segment 20.Since it has been ensured that the traveling waves of the adjacent stator segments 20, 10 are congruent, the transport means 3 can now pass the transition between the second and the first stator segment 20, 10 without undesirable jerky accelerations and can be moved further along the controlled stator segment 10.

Claims

[1] Method for operating a linear motor arrangement (1), comprising the steps of: controlled introduction of electrical energy to a first stator segment (10) equipped with magnetic coils for the controlled provision of a magnetic field to a permanent magnet arrangement (8) of a transport means (3) for generating drive forces, controlled introduction of electrical energy to a second stator segment (20) equipped with a measuring device (9) for determining a position of a transport means (3) and with magnetic coils for the controlled provision of a magnetic field to the transport means (3), wherein a control device (6) upon a transition of the transport means (3) from the first stator segment (10) to the second stator segment (20) and / or upon a transition of the transport means (3) from the second to the first stator segment (20, 10),temporarily switching the second stator segment (20) from the regulated state to a controlled state, and wherein the control device (6) activates an algorithm for determining the position of the transport means (3) for switching between the controlled introduction of electrical energy and the controlled introduction of electrical energy into the second stator segment (20) and, within a predeterminable time period comprising at least two control cycles of the control device (6), reduces a difference between a desired position value for the transport means (3) and an actual position value for the transport means (3) such that the actual position value at the end of the time period corresponds at least substantially to the desired position value. [2] Method according to claim 1, characterized bythat the control device (6) provides an electrical alternating voltage for the magnetic coils during the controlled introduction of electrical energy to the second stator segment (20) in such a way that a phase angle of 90 degrees is established along a movement path (2) of the transport means (3) between an active current component provided to the second stator segment (20) and a position of a magnetic active center (11) of the permanent magnet arrangement (8) of the transport means (3). [3] Method according to claim 2, characterized by that the control device (6) provides an alternating current with a predeterminable frequency dependent on a target speed of the transport means (3) to the magnetic coils during the controlled introduction of electrical energy to the first stator segment (10) and / or regulates a nominal current for the magnetic coils. [4] Method according to claim 2 or 3, characterized bythat the control device (6) changes the phase angle between the active current component provided to the second stator segment (20) and the position of the magnetic active center (11) of the permanent magnet arrangement (8) of the transport means (3) by 90 degrees when the transport means (3) approaches a transition between a second and a first stator segment (20, 10) for switching between the regulated introduction of electrical energy and the controlled introduction of electrical energy into the second stator segment (20). [5] Method according to claim 4, characterized by that the control device (6) carries out a frequency-equal and phase-equal control of the first and second stator segments (10, 20) for a movement of the transport means (3) across the transition between the second and the first stator segment (20, 10). [6] Method according to claim 4 or 5, characterized bythat the control device (6) deactivates a control algorithm for controlling the actual position value of the transport means (3) and / or an algorithm for determining the position of the transport means (3) after changing the phase angle by 90 degrees in order to carry out the switchover to the controlled introduction of electrical energy to the second stator segment (20). [7] Method according to claim 1, characterized byin that, in order to reduce the difference between the desired position value for the means of transport (3) and the actual position value for the means of transport (3), at the beginning of the switchover between the controlled and the regulated introduction of electrical energy into the second stator segment (20), the control device (6) resets at least one integral component of at least one control algorithm for controlling the position and speed of the means of transport (3) to a predeterminable value, in particular zero, and / or the control device (6) increases the current limiting threshold for the second stator segment (20) over a number of controller cycles, starting from a reduced current limiting threshold. [8] Linear motor arrangement (1), with several stator segments (10, 20) arranged in a row and with at least one transport means (3) which is movable relative to the stator segments (10, 20) along a movement path (2), as well as control devices (4, 5) which are each assigned to the stator segments (10, 20) and are designed to provide electrical energy, and a control device (6) for providing control signals to the control devices (4, 5), wherein the stator segments (10, 20) are designed to provide mobile magnetic fields for introducing driving forces onto the transport means (3) which are each equipped with a permanent magnet arrangement (8), wherein the control device (6) is designed for a controlled provision of electrical energy to a first stator segment (10) and for a regulated provision of electrical energy to at least a second,is designed with a stator segment (20) equipped with a measuring device (9) for determining a position of the transport means (3), wherein the control device (6) carries out a temporary switchover of the controlled second stator segment (20) into a controlled state when the transport means (3) transitions from the first stator segment (10) to the second stator segment (20) and / or when the transport means (3) transitions from the second stator segment (20) to the first stator segment (10), and wherein the control device (6) has an algorithm for position determination for the transport means (3) for switching between the controlled introduction of electrical energy and the controlled introduction of electrical energy into the second stator segment (20), which algorithm is designed to, within a predeterminable time period comprising at least two control cycles of the control device (6),to reduce a difference between a position setpoint for the means of transport (3) and an actual position value for the means of transport (3) such that the actual position value at the end of the time period corresponds at least substantially to the position setpoint. [9] Linear motor arrangement (1) according to claim 8, characterized by in that a stator segment (10, 20) comprises a plurality of magnetic coils, preferably arranged at equal pitch along the movement path (2), wherein adjacently arranged magnetic coils are designed such that they provide opposing magnetic fields when jointly controlled by a control device (4, 5).

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