Linear motor system and method of operating a linear motor system

Abstract

The linear motor system comprises a rail with a plurality of electromagnets arranged along the rail, which are supplied with electrical energy by a power supply network, at least one slider guided on the rail and movable along the rail and comprising drive magnets for cooperating with the electromagnets of the rail for moving the slider, a control device for controlling the movement of the slider relative to the rail by energizing a portion of the electromagnets by means of a drive current, which is arranged to energize at least a portion of the electromagnets by means of a damping current, such that said energization by the damping current does not result in additional movement of the slider along the rail and / or does not result in a change of the movement of the slider along the rail generated by the drive current and / or does not result in additional forces on the slider and / or does not result in a change of the forces on the slider generated by the drive current, on the one hand, and / or, on the other hand, wherein said energization by the damping current is performed for reducing oscillations and / or current and voltage fluctuations in the power supply network.

Description

Technical Field

[0001] This invention relates to a linear motor system, particularly a conveying system, such as a multicarrier system. The linear motor system includes a guide rail with a plurality of electromagnets arranged along the rail, these electromagnets being powered by a power grid. At least one slider of the linear motor system is guided on and movable along the guide rail. The slider includes a drive magnet for cooperating with the electromagnets of the guide rail to move the slider. The linear motor system also includes control devices for controlling the movement of the slider relative to the guide rail. Control of the movement is achieved by energizing at least one or only a portion of the electromagnets with a drive current. Background Technology

[0002] Such linear motor systems and, for example, multi-carrier systems are used to transport workpieces in industrial processes and, for example, transfer them from one processing step to the next. To this end, the sliders of such multi-carrier systems can move independently of each other, by means that the electromagnets of the guide rails are controlled in different ways to cause corresponding movements of the sliders.

[0003] The linear motor system's required electrical power changes with the acceleration and braking movement of the slider, resulting in fluctuations in current and voltage in the power grid. Typically, the electromagnet is also supplied with power from the grid via switching converters, where these converters, along with the electromagnet, act as a load with constant power. This load with constant power can act as a negative impedance and trigger oscillations in the power grid.

[0004] Such oscillations and / or current and voltage fluctuations are undesirable and are traditionally reduced, for example, by incorporating large buffer capacity in the linear motor system or by integrating an active converter. A disadvantage in both cases is the need to integrate additional components into the linear motor system, thereby increasing the required installation space. Furthermore, the manufacturing cost for the linear motor system also increases. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a linear motor system that can simplify the reduction of oscillations and / or current and voltage fluctuations in the power grid.

[0006] The aforementioned technical problem is solved by a linear motor system according to the present invention.

[0007] According to the invention, the control device is configured to energize at least a portion of the electromagnet via a damping current, such that the energization via the damping current does not, on the one hand, cause additional movement of the slider along the guide rail and / or cause a change in the movement of the slider along the guide rail generated by the driving current, and / or on the other hand, does not cause additional force on the slider and / or cause a change in the force on the slider generated by the driving current, particularly the force along the guide rail. Here, the energization via the damping current is particularly implemented to reduce oscillations and / or current and voltage fluctuations in the power supply network.

[0008] This invention is based on the knowledge that (damping) current can be introduced into an electromagnet (more precisely, into the coil of the electromagnet) to temporarily store electrical power, thereby reducing, for example, point loads and / or oscillations in a power grid. The electrical power can then be stored as magnetic energy in the magnetic field of the corresponding electromagnet. The electromagnet is preferably a coil with a soft magnetic core. The damping current can be controlled such that it causes damping of oscillations and / or current and / or voltage fluctuations in the power grid.

[0009] Damping current can be used, for example, to dissipate excess energy in the power grid and / or to transfer missing energy from storage in the electromagnet back into the power grid. Therefore, damping current can be used for both energy storage (energy transfer to the electromagnet) and energy recovery (electrical energy fed back from the electromagnet to the power grid).

[0010] Preferably, the damping current does not cause any additional or altered movement of the slider and / or exert any additional or altered force on the slider along the guide rail. In other words, the damping current keeps the corresponding slider movement (or stationary) along the guide rail caused by the drive current constant. "Constantly" here means that no change or variation perceptible to the user is made below a predetermined threshold. For example, the speed change may be less than 3%, 1%, or preferably less than 0.1% of the speed caused by the drive current. When the slider is stationary, the displacement caused by the damping current cannot exceed, for example, 3%, 1%, or 0.1% of the length of the slider along the guide rail.

[0011] However, the damping current can cause the slider to be pulled more or less laterally toward the corresponding electromagnet.

[0012] Advantageously, according to the invention, damping of oscillations and / or current and / or voltage fluctuations can be achieved by components already included in the linear motor system, particularly by the inherent electrical control of the electromagnet. This eliminates the need for additional components, such as large buffer capacities (or buffer capacitors).

[0013] Advantageous improvements to the present invention can be found in the specification and drawings.

[0014] According to the first embodiment, the control device is configured to energize at least a portion of the electromagnets with a damping current, wherein the electromagnets do not cause movement of the slider, particularly along the guide rail, at a given time point. For example, the damping current can be applied to electromagnets too far from the slider, so that movement of the slider cannot be initiated. Of course, it must be considered that electromagnets positioned closer to the slider can be loaded with less damping current, while electromagnets farther from the slider can be loaded with more damping current without causing movement of the slider.

[0015] The basic concept here is to temporarily store electrical energy using currently "unused" electromagnets. Accordingly, one embodiment may also specify that the control device is configured to introduce a damping current into the electromagnet, so that at a given time point, in conventional electromagnet control without a damping current, no driving current flows through the electromagnet.

[0016] According to another embodiment, the control device is configured to introduce a damping current into an electromagnet that is also energized by a driving current. Alternatively, the damping current can also be introduced into an electromagnet that is already being energized by a driving current. Since a damping current through a single electromagnet typically alters the movement of the slider and / or the force on the slider, in this case, the damping current can also be introduced into at least one other electromagnet such that the damping current in all electromagnets (near the respective slider) ultimately does not produce a change in the movement of the slider or any additional movement.

[0017] According to one embodiment, the control device can reduce the drive current in at least one of the plurality of electromagnets by means of a damping current, and for this purpose, introduce the damping current into adjacent electromagnets to compensate for the change in force on the slider due to the reduction in drive current. This can be done, for example, if the drive current in an electromagnet very close to the slider is reduced by a damping current. The resulting smaller force on the slider can be compensated, particularly by an electromagnet located further away, which is energized by a damping current and thus compensates for the smaller force on the slider. Since the distance between the electromagnets energized solely by the damping current is large, a larger current is required there. This larger current can also buffer electrical energy to dampen oscillations in the power grid.

[0018] Therefore, the drive current and damping current can be superimposed in one or more electromagnets according to one embodiment. The current generated by the drive current and damping current produces a magnetic field, which in turn exerts a force on the drive magnet of the slider, thereby causing the slider to move. Here, movement refers to, for example, acceleration, braking, or traveling at a constant speed. Holding the slider in a predetermined position can be caused by the drive current or by the generated current. It is understood that the damping current as a whole (i.e., the damping current in all coils) should (almost) not cause a change in movement and / or a change in the force on the slider, especially a change in the force only along the direction of movement.

[0019] According to another embodiment, the combined drive current and damping current introduced into the electromagnet are at least temporarily greater than the drive current alone, wherein energy is stored in the electromagnet through the larger total current. As described above, the drive current is the current introduced into the electromagnet for normal operation (i.e., for moving the slider) as it is normally used (i.e., without damping current). Since the additional energy from the power grid is buffered in the electromagnet at least temporarily, the total current for the electromagnet is at least temporarily greater than the drive current alone (i.e., during the period of buffering excess energy).

[0020] According to another embodiment, the electromagnet is connected to the power supply network via a switching converter, wherein the switching converter preferably functions as a load with constant power. The switching converter, specifically, together with the electromagnet connected to it, can thus function as a so-called "constant power load" (CPL) and thereby act as a negative impedance, amplifying the oscillation. The oscillation can, for example, be generated through interaction with the capacitance or inductance inherent in the power supply network and / or the linear motor system. The switching converter is preferably arranged between the power supply network and the electromagnet. The switching converter can be, in particular, a DC-DC converter, but can also be an AC-DC converter.

[0021] As described below, a linear motor system can be divided into multiple sections. Preferably, a separate switching converter is provided in each section and / or each coil or electromagnet.

[0022] In another embodiment, the power supply network is a DC power grid, preferably with a voltage less than 80V or less than 60V. Therefore, the power supply network can be a so-called DC-Grid. Multiple, and preferably all, of the switching converters of the linear motor system can be connected in parallel to the power supply network. The power supply network for this purpose may in particular include power rails or the like, with which the switching converters are particularly directly electrically connected. Multiple switching converters are preferably connected in parallel to the power supply network.

[0023] According to another embodiment, the control device is configured to consider the induced voltage (EMK - electromotive force) generated by the slider in one of the plurality of electromagnets as the slider moves, for selecting at least one electromagnet energized with a damping current. The control device may measure and / or calculate or otherwise determine the induced voltage. The measurement is performed while the slider is moving. A measurement taken once can be stored and repeated for similar slider positions and / or slider velocities. Based on the induced voltage, it can then be determined which electromagnets are subsequently energized with a damping current.

[0024] The magnitude of the induced voltage is a measure of how efficiently the current in the electromagnet generates a force on the slider. For example, these electromagnets, used for applying damping current, can be specified such that the induced voltage is below a predetermined threshold. The specified electromagnet is then energized with a damping current.

[0025] Of course, the induced voltages used for different electromagnets can be detected simultaneously.

[0026] Alternatively or additionally, the ratio of the induced voltage can be determined for at least two pairs of multiple electromagnets. A damping current can then be introduced into the electromagnet inversely proportional to this ratio.

[0027] In particular, the induced voltage for one electromagnet can be determined first, and then the induced voltage of at least one other electromagnet can be compared to this. If the ratio (or the amount of the ratio) exceeds a predetermined threshold, the electromagnet with the smaller induced voltage can be designated for passing the damping current and then energized with the damping current. For example, when the slider moves, a voltage of 18V can be induced in the first electromagnet. The first electromagnet can, for example, be located very close to the drive magnet of the slider. Conversely, the induced voltage in the second electromagnet, for example, farther from the drive magnet, can be -1.56V, purely exemplary. The ratio of the amount is 11.5. If a ratio of at least 10 is now considered as a predetermined threshold, then the second electromagnet is now designated for passing the damping current. It is also possible to determine the induced voltages for two second electromagnets, which are arranged symmetrically with respect to the first electromagnet. If, during the application of damping current, the current generated in the first electromagnet decreases by, for example, 5%, then the current generated in the two second electromagnets can be increased to a greater extent, by the aforementioned proportion, i.e., for example, 5% * 11.5 = 57.5%. This is also referred to below. Figure 8 illustrate.

[0028] According to another embodiment, the control device is configured to generate a negative damping current at least temporarily for at least one of the plurality of electromagnets in order to input electrical energy into the power grid. Alternatively or additionally, the control device may be configured to generate a positive damping current at least temporarily for at least one electromagnet in order to output electrical energy from the power grid. As described above, the energy stored in the electromagnets can be fed back into the power grid, thereby also reducing oscillations and / or current and / or voltage fluctuations. Inputting or feeding back electrical energy can also cover load peaks, for example, during slider start-up or strong acceleration.

[0029] According to another embodiment, the linear motor system has multiple sections, each section comprising multiple electromagnets, wherein control devices are preferably distributed across multiple sections. The sections or portions of the control devices can communicate with each other. This is preferably via section-to-section (S2S) communication, for example via a fieldbus (such as Sercos). Damping currents can be calculated and generated for each section, wherein the control device for one section can control only the electromagnets of its corresponding section, or alternatively, the damping current can be introduced into the electromagnets of other sections. It is also possible for the control devices of different sections to jointly determine the damping current and distribute it to different electromagnets.

[0030] In another embodiment, at least one sensor is provided, wherein the sensor detects current and / or voltage in the power supply network and converts it into a sensor signal. The sensor signal can then serve as the basis for generating a damping current. It is also feasible to have individual sensors in each or more sections to detect location-dependent oscillations and / or current and voltage fluctuations in the power supply network. The respective sensors can then be coupled to control equipment located in the corresponding section.

[0031] According to another embodiment, the control device includes a control loop for generating a damping current, wherein the control loop includes a simulation device for negative impedance and a simulation device for the damping element, which will also refer to... Figure 4Detailed explanation. The simulation devices can be models, such as analog models or mathematical models. Preferably, the control loop outputs a control signal, which serves as the basis for the damping current. The aforementioned sensor signals can be input signals for the control loop. The output values ​​of the simulation devices for damping elements and / or negative impedance can be superimposed on the input signals in the control loop. This means that the output values ​​can be fed back to the input signals. By setting up simulation devices for negative impedance and damping elements, the effect of a load with constant power and the desired damping effect (which may be equivalent to a large buffer capacitor, for example) can be simultaneously simulated in the control loop. The control signal output by the control loop then automatically results in the desired damping effect (such as reducing oscillations) being achieved through the damping current. By simply setting up the simulation devices for damping elements in the control loop, the more complex calculations of the damping current can be omitted.

[0032] The control loop is preferably arranged in the control device and implemented, for example, by software. According to another embodiment, the control loop includes logic that determines the damping current for the electromagnet from the control signals, particularly based on additional boundary conditions. The magnitude of the damping current at a given time point can be determined from the control signals.

[0033] When determining the damping current, especially through the control loop, the voltage and / or current induced in the electromagnet by the driving magnet of the slider (the so-called "back EMF") can also be considered.

[0034] However, as mentioned above, the damping current can be achieved in different ways, such as by introducing it into a coil that is not currently in use or by correspondingly changing the drive current in multiple coils. The logic can now determine the precise magnitude and distribution of the damping current. For this purpose, the current coil temperature, current power, and the direction of slider movement can be used as boundary conditions, for example. For instance, a coil that has already become severely heated is not considered for the damping current so as not to cause it to continue heating. The damping current can also be introduced into a coil that does not necessarily need to be immediately used to move the slider by the drive current (based on the direction of slider movement).

[0035] According to another embodiment, the linear motor system includes multiple sections, each section including multiple electromagnets, wherein the sections are arranged in a queue and form a surrounding guide rail, wherein the guide rail is arranged on the outer side of the respective section. The sections may, for example, each have their own housing and are electrically connected to each other, for example, via a plug connector. Two mechanical guide rails may, for example, be arranged on the outer side of the section, along which a slider's wheel travels to guide the slider. Electromagnets may be arranged between the two guide rails, wherein the slider is pulled in the direction of the guide rail by a drive magnet. The slider may each include a corner such that the slider has a fixed surface along the guide on the top side of the section and for receiving and / or transporting workpieces.

[0036] The guide rail is preferably designed to wrap around the slider, so that the slider moves substantially continuously along the guide rail in the same direction. The linear motor system further preferably includes a straight section and a section in which the guide rail forms a curve. The electromagnet is correspondingly arranged along the guide rail along a straight or curved line.

[0037] Another aspect of the present invention is a method for operating a linear motor system, particularly a conveying system, such as a multi-carrier system, wherein the linear motor system comprises:

[0038] - A guide rail, with multiple electromagnets arranged along the rail, these electromagnets being powered by the power grid.

[0039] - At least one slider, which is guided on and movable along a guide rail, and includes a drive magnet for cooperating with an electromagnet on the guide rail to move the slider.

[0040] - A control device for controlling the movement of a slider relative to a guide rail, which is achieved by energizing a portion of an electromagnet with a driving current.

[0041] The method according to the invention is characterized in that at least a portion of the electromagnet is energized by a damping current such that the energization by the damping current does not, on the one hand, cause additional movement of the slider along the guide rail and / or cause a change in the movement of the slider along the guide rail generated by the driving current, and / or on the other hand, cause additional force on the slider and / or cause a change in the force on the slider generated by the driving current, especially the force along the guide rail, wherein the energization by the damping current is performed to reduce oscillations and / or current and voltage fluctuations in the power grid.

[0042] The description relating to the linear motor system according to the invention is correspondingly applicable to the method according to the invention. This is especially true regarding advantages and implementation methods. Attached Figure Description

[0043] The invention is described below by way of example only, with reference to the accompanying drawings. Wherein:

[0044] Figure 1 This illustrates a linear motor system configured as a conveyor system.

[0045] Figure 2 Show Figure 1 The curved section of a linear motor system,

[0046] Figure 3 Using a cross-section perpendicular to the guide rail to illustrate Figure 1 A three-dimensional cross-sectional view of a linear motor system.

[0047] Figure 4A circuit diagram for controlling the current in an electromagnet is shown.

[0048] Figure 5 A schematic diagram of the electromagnet of the conveying system is shown, along with a graph of the damping current introduced into the electromagnet located away from the slider.

[0049] Figure 6 This illustrates how a damping current is introduced into the electromagnet without exerting a force on the slider.

[0050] Figure 7 This illustrates the effect of damping current on the driving current.

[0051] Figure 8 This illustrates the selection of an electromagnet for damping current based on the induced current. Detailed Implementation

[0052] Figure 1 The diagram shows a linear motor system 11 designed as a multi-carrier system. The linear motor system 11 includes multiple sections 13 arranged in a queue to achieve continuous, in this case, cyclical movement of sliders 15 along guide rails 17. Furthermore, the conveying system 11 includes multiple sliders 15, which constitute individual conveying elements of the conveying system 11 and can be conveyed by means of sections 13 (e.g., ...). Figure 3 The electromagnets (as shown) move independently along guide rail 17. Section 13 and slider 15 together constitute a linear motor.

[0053] Figure 2 The curved section of the linear motor system 11 is shown in an enlarged view. Only one slider 15 is shown here, which can move along the guide rail 17 via the section 13. On the side of the guide rail 17 opposite to the slider 15, i.e. inside the curved section, various electronic devices for controlling the section 13 can be seen.

[0054] exist Figure 3 The linear motor system 11 is shown in a sectional view and magnified. A slider 15 can be seen, which is movably guided on a guide rail 17. Here, the slider 15 is movable along a guide axis 19 or a movement axis. For movement along the guide axis 19, the slider 15 is controlled by a plurality of electromagnets 21, which are arranged on the guide rail 17 and evenly distributed along the rail. The electromagnets 21 here work in conjunction with permanent magnets 23 arranged on the slider 15 to drive the slider 14; the permanent magnets 23 can also be referred to as driving magnets.

[0055] The slider 15 is mechanically guided on the guide rail 17, i.e., by a roller guide device. This includes guide rollers 25 on the slider 15 and guide rails 27 on the guide rail 17. The slider 15 is held on the guide rail 17 here, in particular, by a permanent magnet 23.

[0056] The linear motor system 11 also includes a position detection device 29. For example, it can be configured as a column of multiple magnetic sensors extending along the guide rail 17. For example, a permanent magnet 31, which can also be referred to as a position magnet, can be disposed on the slider 15. Figure 2 As you can see.

[0057] Figure 4 A circuit diagram is shown for controlling the current in the coil of electromagnet 21. Electromagnet 21 is electrically connected to DC power grid 35 via its own switching converter 33. Control device 37 controls the current through electromagnet 21, particularly via transistor 34 shown in switching converter 33 and electronic control device 36 connected upstream of transistor 34. Transistor 34 optionally establishes an electrical connection between power grid 35 and electromagnet 21.

[0058] In addition, current sensor 38 and voltage sensor 42 are also connected to power grid 35. The signal from current sensor 38 is input to control device 37.

[0059] The signal from voltage sensor 42, particularly the digitized signal, is input to model 44, which consists of a negative impedance (“1 / R_damp”) and a damping capacitance (“1 / C_damp”). The damping capacitance model is in the feedback loop and is subtracted from the signal from voltage sensor 42. This model 44, together with the control loop of control device 37, dampens oscillations in power supply network 35. This model 44 is, of course, arranged within the control device and is shown externally only for better understanding.

[0060] Figure 5 The diagram shows the electromagnet 21 of section 13 relative to the slider 15 or its driving magnet 23. Here, the north and south poles of the driving magnet 23 are shown separately.

[0061] Figure 5 The diagram also shows the driving current 39 on different electromagnets 21. The driving current 39 shown here is the superposition of currents introduced in different electromagnets 21, where positive and negative values ​​indicate the current direction. The driving current 39 shown causes the slider 15 to move.

[0062] As can be seen, in Figure 5 The coil of the electromagnet 21 shown at the right edge is not loaded with the driving current 39. These electromagnets 21 are too far from the slider 15 to exert a force on it. According to... Figure 5 Damping current 41 is introduced into these electromagnets 21, which temporarily stores the energy from the power grid 35 in these electromagnets 21.

[0063] The position detection device 29 can be used to determine the electromagnet 21 that must be driven by the drive current 39 to move the slider 15. Furthermore, the control device 37 can also be configured to detect the current induced in the electromagnet 21 by the drive magnet 23 of the slider 15 and thereby determine or verify the position of the slider 15.

[0064] Another implementation for generating the damping current 41 is in Figure 6 The diagram is shown. In this embodiment, a damping current 41 is introduced into the electromagnets 21, which are also loaded with a drive current 39. The dotted line shows a typical curve of the drive current 39 when the slider 15 moves on the coil at a constant speed and force. The current curve of the drive current 39 is typically chosen such that the force exerted by all the electromagnets 21 together on the slider is as linear as possible, while simultaneously striving to achieve a small total current. Of course, alternative current curves for the drive current 39 are possible.

[0065] Figure 6 The diagram also shows a feasible scheme for the damping current 41, indicated by dashed lines. The damping current 41 is suitable for situations where the slider 15 travels at a constant speed on the electromagnet 21, wherein no force is exerted on the slider 15 in the direction of movement by means of the damping current 41.

[0066] Finally, the resulting coil current 43 is shown as a dotted line. The coil current 43 is generated by the drive current 39 and the damping current 41 as the current that actually flows into the electromagnet 21.

[0067] Figure 7 Another embodiment for implementing the damping current 41 is shown. Figure 7 The left-hand diagram shows the "normal" current distribution of the drive current 39. The induced coil current 40 is also shown. By changing the drive current 39 with the damping current 41, the resulting coil current 43 can be achieved, which in Figure 7 As shown in the diagram on the right, it can be seen that the larger current share is farther away from slider 15. Due to the greater distance, the force acting on slider 15 remains unchanged. However, it is possible that additional electrical energy is stored in the electromagnet 21 of the linear motor system.

[0068] Figure 8 The diagram shows the selection of the electromagnet 21 for damping the current based on the induced current. The dotted line shows a typical curve of the driving current 39 when the slider 15 moves on the coil at a constant speed and force (also as shown). Figure 6 ).

[0069] The solid line shows a possible curve of the voltage (electromotive force) 45 induced in the electromagnet 21 (i.e., its coil) when the slider 15 moves at a constant speed on the electromagnet 21. The shape of the curve of the induced voltage 45 is a measure of how efficiently the current in the electromagnet generates a force on the slider 15.

[0070] In the slider positions shown Figure 8 The induced voltage 45 of the electromagnet 21, designated "Coil 2", is the highest (18V). Conversely, it is significantly lower (-1.56V) in "Coil 0" and "Coil 4", which are arranged symmetrically to "Coil 2". The ratio of induced voltages is 11.5.

[0071] Based on this efficiency (i.e., the amount of the induced voltage 45), it can be determined in which electromagnet 21 the driving current 39 is reduced (here, "coil 2"; i.e., the negative damping current), and in which electromagnet 21 a corresponding positive damping current 41 is introduced (in this example, in "coil 0" and "coil 4"). To keep the force on slider 15 constant, in this position, for example, the driving current 39 is reduced by 5% in "coil 2" and increased by 5% * 11.5 = 57.5% in "coil 0" and "coil 4". The total current flowing through electromagnet 21 is thus increased, and electrical energy is thus stored in electromagnet 21.

[0072] By temporarily storing electrical energy in the electromagnet 21, oscillations and / or current and voltage fluctuations in the power grid 35 can be reduced.

[0073] List of reference numerals in the attached diagram:

[0074] 11 Linear Motor System

[0075] 13 sections

[0076] 15 sliders

[0077] 17 guide rails

[0078] 19 guide axes

[0079] 21 Electromagnets

[0080] 23 driving magnets

[0081] 25 guide rollers

[0082] 27 guide rails

[0083] 29 Position Detection Equipment

[0084] 31 position magnet

[0085] 33-Switch Converter

[0086] 34 transistors

[0087] 35 power supply network

[0088] 36 electronic control devices

[0089] 37 Control Equipment

[0090] 38 Current Sensor

[0091] 39 drive current

[0092] 40 induced coil current

[0093] 41 Damping Current

[0094] 42 Voltage Sensor

[0095] 43 generates coil current

[0096] 44 Model

[0097] 45 induced voltage

Claims

1. A linear motor system (11), comprising: The guide rail (17) has a plurality of electromagnets (21) arranged along the guide rail (17), the electromagnets being powered by a power grid (35); At least one slider (15) is guided on and movable along the guide rail (17) and includes a drive magnet (23) for cooperating with an electromagnet (21) of the guide rail (17) to move the slider (15). A control device (37) is used to control the movement of the slider (15) relative to the guide rail (17), which is achieved by energizing a portion of the electromagnets with a drive current (39). The control device (37) is configured to energize at least a portion of the electromagnet (21) via a damping current (41) such that the energization via the damping current (41) does not, on the one hand, cause additional movement of the slider (15) along the guide rail (17) and / or cause a change in the movement of the slider (15) along the guide rail (17) generated by the driving current (39), and / or on the other hand, does not cause additional force on the slider (15) and / or cause a change in the force on the slider (15) generated by the driving current (39). The energization via the damping current (41) is performed to reduce oscillations and / or current and voltage fluctuations in the power grid (35). Its features are, The control device (37) is configured to reduce the drive current (39) in at least one of the plurality of electromagnets (21) by means of a damping current (41) and to do so, to introduce the damping current (41) into an adjacent electromagnet (21) to compensate for the change in force on the slider (15) due to the reduction of the drive current (39).

2. The linear motor system (11) according to claim 1, Its features are, The control device (37) is configured to energize at least a portion of these electromagnets (21) with a damping current (41), which do not cause the slider (15) to move at the corresponding time points.

3. The linear motor system (11) according to claim 1 or 2, Its features are, The control device (37) is configured to introduce a damping current (41) into the electromagnet, at a corresponding time point, when no driving current (39) flows through the electromagnet.

4. The linear motor system (11) according to claim 1 or 2, Its features are, The control device (37) is configured to introduce a damping current (41) into an electromagnet (21) that is also energized by a drive current (39).

5. The linear motor system (11) according to claim 1 or 2, characterized in that, The driving current (39) and the damping current (41) are superimposed in one or more electromagnets (21).

6. The linear motor system (11) according to claim 1 or 2, Its features are, The combined driving current (39) and damping current (41) introduced into the electromagnet (21) are at least temporarily greater than the driving current (39) itself, wherein energy is stored in the electromagnet (21) through the larger total current.

7. The linear motor system (11) according to claim 1 or 2, Its features are, The electromagnet (21) is connected to the power grid (35) via a switch converter, wherein the switch converter acts as a load with constant power.

8. The linear motor system (11) according to claim 1 or 2, Its features are, The control device (37) is configured to take into account the induced voltages in the plurality of electromagnets (21) caused by the slider (15) as it moves, for selecting at least one electromagnet (21) that should be energized with a damping current.

9. The linear motor system (11) according to claim 1 or 2, Its features are, The control device (37) is configured to generate a negative damping current (41) at least temporarily for at least one electromagnet (21) in order to input electrical energy into the power grid (35). and / or The control device (37) is configured to generate a positive damping current (41) at least temporarily for at least one electromagnet (21) in order to output electrical energy from the power grid (35).

10. The linear motor system (11) according to claim 1 or 2, Its features are, The linear motor system (11) has multiple sections (13), each section including multiple electromagnets (21), wherein the control device (37) is distributed on multiple sections (13).

11. The linear motor system (11) according to claim 1 or 2, Its features are, The device is equipped with a sensor that detects current and / or voltage in the power grid (35) and converts it into a sensor signal. The control device (37) includes a control loop for generating a damping current (41), wherein the control loop includes a simulation device for negative impedance and a simulation device for damping elements.

12. The linear motor system (11) according to claim 11, Its features are, The control loop includes logic that determines a damping current (41) for the electromagnet (21) based on additional boundary conditions from the control signal.

13. The linear motor system (11) according to claim 1 or 2, Its features are, The linear motor system (11) includes multiple sections (13), each section (13) including multiple electromagnets (21), wherein the sections (13) are arranged in a queue and form a surrounding guide rail (17), wherein the guide rail (17) is arranged on the outside of the respective section (13).

14. A method for operating a linear motor system (11), wherein, The linear motor system (11) includes: The guide rail (17) has a plurality of electromagnets (21) arranged along the guide rail (17), the electromagnets being powered by a power grid (35); At least one slider (15) is guided on and movable along the guide rail (17) and includes a drive magnet (23) for cooperating with an electromagnet (21) of the guide rail (17) to move the slider (15). A control device (37) is used to control the movement of the slider (15) relative to the guide rail (17), which is achieved by energizing a portion of the electromagnets with a drive current (39). Wherein, at least a portion of the electromagnet (21) is energized by a damping current (41) such that the energization by the damping current (41) does not, on the one hand, cause additional movement of the slider (15) along the guide rail (17) and / or cause a change in the movement of the slider (15) along the guide rail (17) generated by the driving current (39), and / or on the other hand, cause no additional force on the slider (15) and / or cause a change in the force on the slider (15) generated by the driving current (39). The energization via the damping current (41) is performed to reduce oscillations and / or current and voltage fluctuations in the power grid (35). Its features are, The control device (37) is configured to reduce the drive current (39) in at least one of the plurality of electromagnets (21) by means of a damping current (41) and to do so, to introduce the damping current (41) into an adjacent electromagnet (21) to compensate for the change in force on the slider (15) due to the reduction of the drive current (39).

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