Drive System

Abstract

A drive system for driving a and/or being driven by a coupled machine comprises an output for driving the and/or by the coupled machine, a first machine unit with at least one electric machine and a second machine unit with at least one electric machine. The first machine unit has a transmission gear and the drive system has a first switching unit which is set up in such a way that, in a first operating state of the first switching unit, it operatively connects the transmission gear of the first machine unit and the output in a torque-transmitting manner and, in a second operating state of the first switching unit, this operative connection is interrupted. In addition or alternatively, the drive system has a first switching device which is set up in such a way that, in a first operating state of the first switching device, the electrical machine of the first or second machine unit and a power supply and/or energy storage device are electrically connected by it, and, in a second operating state of the first switching device, said connection is disconnected and an active short circuit of said electrical machine is effected.

Claims

1-17. (canceled)

18. A drive system for driving or being driven by a machine coupled with the drive system, the drive system comprising: an output configured for at least one of driving or being driven by the coupled machine; a first machine unit comprising at least one first electric machine for at least one of driving or being driven by the output; and a second machine unit comprising at least one second electric machine for at least one of driving or being driven by the output; wherein at least one of: a) the first machine unit comprises a transmission gear arranged to at least one of be driven by the first electric machine or to drive the first electric machine, and the drive system comprises a first switching device configured such that: in a first operating state of the first switching device, the transmission gear of the first machine unit and the output are operatively mechanically connected in a torque-transmitting manner, and in a second operating state of the first switching device, the operative connection between the transmission gear of the first machine unit and the output is interrupted; or b) the drive system has a second switching device configured such that: in a first operating state of the second switching device, one of the first or second electric machines and at least one of a power supply or an energy storage device are electrically connected, and in a second operating state of the second switching device, the connection to the at least one of a power supply or an energy storage device is electrically disconnected and an active short-circuit of the first or second electric machines is effected.

19. The drive system of claim 18, wherein at least one of: a) the second machine unit comprises a transmission gear adapted to at least one of be driven by the second electric machine or to drive the second electric machine, and the drive system comprises a third switching device configured such that: in a first operating state of the third switching device, the transmission gear of the second machine unit and the output are operatively connected in a torque-transmitting manner, and in a second operating state of the third switching device, the operative connection between the transmission gear of the second machine unit and the output is interrupted; or b) the drive system comprises a fourth switching device configured such that: in a first operating state of the fourth switching device, the other of the first or second electric machines is electrically connected with at least one of a power supply or an energy storage device, and in a second operating state of the fourth switching device, the connection to the at least one of a power supply or energy storage device is disconnected and an active short-circuit of the other of the first or second electrical machines is effected.

20. The drive system of claim 19, wherein the drive system is configured such that at least one of: A) in at least one operating state of the drive system, the first switching device has its first operating state and the second switching device has its first operating state, and in at least one other operating state of the drive system: the first switching device has its second operating state and the second switching device has its first operating state, or the first switching device has its first operating state and the second switching device has its second operating state, or the first switching device has its second operating state and the second switching device has its second operating state; B) in at least one operating state of the drive system, the first switching device has its first operating state and the third switching device has its first operating state, and in at least one other operating state of the drive system: the first switching device has its second operating state and the fourth switching device has its first operating state, or the first switching device has its first operating state and the fourth switching device has its second operating state; or the first switching device has its second operating state and the fourth switching device has its second operating state: or C) in at least one operating state of the drive system, the second switching device has its first operating state and the fourth switching device has its first operating state, and in at least one other operating state of the drive system: the second switching device has its second operating state and the fourth switching device has its first operating state, or the second switching device has its first operating state and the fourth switching device has its second operating state, or the second switching device has its second operating state and the fourth switching device has its second operating state.

21. The drive system of claim 19, wherein at least one of the first or third switching devices has at least one freewheel.

22. The drive system of claim 19, wherein at least one of the first or third switching devices has at least one selectively switchable clutch.

23. The drive system of claim 19, wherein at least one of: at least one of the transmission gears and/or the output comprises at least one of: at least one spur gear, or at least one planetary gear: or at least one of the transmission gears and/or the output is configured such that an input speed of the coupled electric machine is converted into either a smaller output speed or a larger output speed on the output side.

24. The drive system of claim 19, wherein at least one of the second or fourth switching devices in the second operating state is adapted to short-circuit terminals of the respective electric machine, thereby causing an active short-circuit of the electric machine.

25. The drive system of claim 19, wherein at least one of the second or fourth switching devices comprises power electronics, in particular of a frequency converter, or is integrated into power electronics.

26. The drive system of claim 19, wherein at least one of the second or fourth switching devices in the second operating state is arranged to cause an active short-circuit of an electric machine from a machine unit in response to at least one of: the transmission gear of the respective machine unit has a malfunction; or the first or third switching device for interrupting the active connection between the transmission gear of the respective machine unit and the output has a malfunction.

27. The drive system claim 19, further comprising a controller configured for at least one of: controlling at least one of the electrical machines; switching at least one of the switchable couplings; or switching at least one of the switching devices.

28. The drive system of claim 27, wherein at least one of: controlling at least one of the electrical machines comprises controlling on the basis of a state of at least one of the drive system or the coupled machine; or switching at least one of the switchable couplings or switching devices comprises switching on the basis of a state of at least one of the drive system or the coupled machine.

29. The drive system of claim 28, wherein the state of at least one of the drive system or the coupled machine is detected by sensors.

30. The drive system of claim 19, wherein the drive system is adapted to operate with a drive power of the coupled machine of at least 0.5 MW.

31. A machine system, comprising: a drive system according to claim 18; and a machine coupled with the drive system such that the machine at least one of drives the drive system, or is driven by the drive system.

32. The machine system of claim 31, wherein the machine drives the drive system, or is driven by the drive system, with a drive power of at least 0.5 MW.

33. A method of operating a machine system, the method comprising: obtaining a machine system according to claim 31; and at least one of: jointly driving the output with at least the first electric machine and the second electric machine in a motor operating state of the drive system, wherein at least one of the first switching device or the second switching device is in the first operating state; or jointly driving at least the first electric machine and the second electric machine with the output in a generator operating state of the drive system, wherein at least one of the first switching device or the second switching device is in the first operating state.

34. The method of claim 33, wherein at least one of: the motor operating state of the drive system is a full-load operating state; in the motor operating state of the drive system, the output is further driven by an electric machine of a further machine unit, jointly with the first electric machine and the second electric machine; the generator operating state of the drive system is a full-load operating state; or in the generator operating state of the drive system, the electric machine of the further machine unit is further driven by the output, jointly with the first electric machine and the second electric machine.

35. The method of claim 33, further comprising at least one of: switching from a first motor operating state to a second, different motor operating state of the drive system, wherein at least one of the machine units continues to drive the output, by at least one of a) transferring at least one of the first or third switching devices from the first operating state to the second operating state, or b) transferring at least one of the second or fourth switching devices from the first operating state to the second operating state; or switching from a first generator operating state to a second, different generator operating state of the drive system, wherein at least one machine unit is driven by the output, by at least one of a) transferring at least one of the first or third switching devices from the first operating state to the second operating state, or b) transferring at least one of the second or fourth switching devices from the first operating state to the second operating state.

36. The method of claim 35, wherein at least one of the second motor operating state or the second generator operating state is a partial load operating state.

37. The method of claim 33, wherein at least one of: at least one of the electrical machines is controlled on the basis of at least one of a state of the drive system or a state of the coupled machine; at least one of the switchable couplings is switched on the basis of at least one of a state of the drive system or a state of the coupled machine; or at least one of the switching devices is switched on the basis of at least one of a state of the drive system or a state of the coupled machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0114] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the principles of the invention.

[0115] FIG. 1 schematically illustrates an exemplary machine system having a drive system according to one embodiment of the present invention;

[0116] FIG. 2 schematically depicts the machine system with the drive system in axial view and corresponding to section line II-II in FIG. 1; and

[0117] FIG. 3 illustrates a method of operating the machine system according to one embodiment of the present invention.

DETAILED DESCRIPTION

[0118] FIGS. 1, 2 show a machine system with a drive system according to one embodiment of the present invention in plan view (FIG. 1) and axial view (FIG. 2), respectively.

[0119] The machine system comprises a coupled machine 70 and the drive system.

[0120] In one embodiment, the coupled machine 70 may be a working machine or a prime mover or, in one embodiment, may be operated or function alternately temporarily as a working machine and temporarily as a prime mover. In the following, the invention will be explained in particular with reference to the example of a coupled working machine, but without being limited thereto.

[0121] The drive system comprises an output having a (collector) gear 51 and an output shaft 52 for driving the coupled machine(s) 70. In variations not shown, the output may also include a multi-stage gear.

[0122] The drive system comprises, by way of example, four machine units, each with an electric machine 10, 20, 30 and 40, respectively, and a transmission gearbox 11, 21, 31 (the fourth transmission gearbox is concealed in the views of FIGS. 1, 2) that can be driven by or drives them, as well as four switching units 12, 22, 32 and 42, respectively.

[0123] On the output side, the switching units are coupled to the gearwheel 51 via pinions 13, 23, 33 and 43, respectively, wherein in one embodiment the pinions are permanently in engagement with the gearwheel 51 and the switching units 12, 22, 32, 42 each have at least one freewheel or each have at least one selectively shiftable clutch, in particular can consist thereof. In one variation, the pinions 13, 23, 33, 43 can be selectively engaged with and disengaged from the gear wheel 51 by means of the corresponding(associated) switching units. Similarly, mixed forms are also possible in which the switching units 12, 22, 32, 42 are designed differently, for example two switching units comprise freewheels and two selectively shiftable couplings or the like.

[0124] Additionally, in the embodiment example, for each of the electric machines 10, 20, 30 and 40, respectively, a switching device 14, 24, 34 and 44, respectively, is provided, by means of which, in a first operating state of the corresponding switching device, the associated electric machine and a power supply and/or energy storage device 80 are or become electrically connected (i.e. (i.e. 8014-10; 8024-20; 8034-40; 8044-40) and, in a second operating state of the corresponding switching device, this connection to the power supply and/or energy storage device 80 is/are disconnected and an active short circuit of the associated electrical machine is/are effected.

[0125] A controller 60 receives information about the state of the machine system, in one embodiment of the drive system, from one or more sensors, one sensor 61 of which is indicated by way of example. Based on this sensor-detected state, the control 60 controls the electric machines 10, 20, 30, 40 and, if applicable, the optionally switchable clutches or the shifting of the pinions 13, 23, 33 or 43 into or out of engagement with the gear 51, which is indicated by dash-dotted lines in FIG. 1. Additionally, the control 60 controls the switching devices, which is also indicated by dashed dots in FIG. 1.

[0126] FIG. 3 shows a method of operating the machine system according to one embodiment of the present invention, initially focusing on the first aspect and a motorized operation or a working machine 70.

[0127] In a step S10, the electric machines 10 and 40, if necessary further, are energized and the switching units 12, 42 are brought into their first operating state or held there, so that by means of these switching units 12, 42 the transmission gear 11 coupled to the electric machine 10 and the transmission gear coupled to the electric machine 40 and concealed in the views of FIGS. 1, 2 are operatively connected in a torque-transmitting manner to the (gear 51 of the) output drive(s).

[0128] If in step S20 a corresponding state of the machine or drive system is detected (S20: “Y”), for example a drive power requirement exceeding a first limit value or the like, the electric machine 20 is, if necessary further, energized and the switching units 22 are brought into their first operating state or held there, so that by means of this switching unit 22 the transmission gear 21 coupled to the electric machine 20 is operatively connected in a torque-transmitting manner to the (gear 51 of the) output drive(s) (step S30).

[0129] If a corresponding state of the machine or drive system is detected in step S40 (S40: “Y”), for example a drive power requirement which also exceeds a higher second limit value, or the like, the electric machine 30 is also energized, if necessary further, and the switching unit 32 is brought into its first operating state or held there, so that by means of this switching unit 32 the transmission gear 31 coupled to the electric machine 30 is operatively connected to the (gear 51 of the) output drive(s) in a torque-transmitting manner (step S50).

[0130] Thus, all four switching units are in their first operating state and the gear 51 or the coupled machine 70 are driven in common by the four energized electric machines 10, 20, 30, 40.

[0131] The procedure then returns to step S10.

[0132] If in step S40 a corresponding state of the machine or drive system is detected (S40: “N”), for example a drive power requirement which exceeds the first limit value but not the higher second limit value, the electric machine 30 is not energized, or if necessary no longer energized, and the switching unit 32 is brought into its second operating state or held there, so that by means of this switching unit 32 the above-mentioned operative connection between the transmission gear 31 and the (gear 51 of the) output drive(s) is interrupted (step S60).

[0133] Thus, all switching units except the third switching unit 32 are in their first operating state and the gear 51 or the coupled machine 70 are driven (only) by the three electric machines 10, 20, 40 in common.

[0134] The procedure then returns to step S10.

[0135] If in step S20 a corresponding state of the machine or drive system is detected (S20: “N”), for example a drive power requirement which also does not exceed the first limit value, the electrical machine 20 is not energized, or if necessary no longer energized, and the switching unit 22 is brought into its second operating state or held there, so that by means of this switching unit 22 the above-mentioned operative connection between the transmission gear 21 and the (gear 51 of the) output drive(s) is interrupted (step S70).

[0136] Thus, all switching units except the second and third switching units 22, 32 are in their first operating state and the gear 51 or the coupled machine 70 are (only) driven jointly by the two electric machines 10, 40.

[0137] The procedure then returns to step S10.

[0138] The above embodiment example serves to illustrate a successive coupling or decoupling of the second machine unit 20, 21 and further machine unit 30, 31 for realizing a full-load operating state (cf. FIG. 3: S50), a first partial-load operating state (cf. FIG. 3: S30) and a second partial-load operating state (cf. FIG. 3: S70) by means of a simple example. Although exemplary embodiments have been explained in the preceding description, it should be noted that a large number of variations are possible.

[0139] In particular, analogous to the above and following explanation, the coupled machine 70 can also be a prime mover or alternately be operated or function temporarily as a working machine and temporarily as a prime mover. Also then, in the manner described above and below, one or more of the electric machines or machine units can be successively coupled or uncoupled and/or connected or actively short-circuited to the power supply.

[0140] Additionally or alternatively to decoupling by means of the switching units as described by way of example above, the controller 60 may analogously actively short-circuit one or more of the electrical machines by the switching device(s) associated with the respective electrical machine by (re)switching corresponding switching device(s) from its first to its second operating state. Conversely, additionally or alternatively to coupling by means of the switching units, the controller 60 may analogously electrically (re)connect one or more of the electrical machines to the power supply and/or energy storage device 80 through the switching device(s) associated with the respective electrical machine by (re)switching corresponding switching device(s) from its second to its first operating state.

[0141] For example, in the variation described below, the switching units 12, 22, 32, 42 may all remain in their respective first operating states or may be omitted and, in step S10, the electrical machines 10 and 40 may, if necessary, continue to be energized via the respective switching devices 14, 44 in their first operating states.

[0142] If a corresponding state of the machine system or drive system is detected in step S20 (S20: “Y”), for example a drive power requirement exceeding a first limit value or the like, the electric machine 20 is also energized via its associated switching device 24, if necessary further, and for this purpose the switching devices 24 are brought into their first operating state or held there (step S30).

[0143] If a corresponding state of the machine system or drive system is detected in step S40 (S40: “Y”), for example a drive power requirement which also exceeds a higher second limit value, or the like, the electric machine 30 is also energized via the switching device 34 assigned to it, if necessary further, and for this purpose the switching device 34 is brought into its first operating state or held there (step S50).

[0144] Thus, all four switching devices are in their first operating state and the gear 51 or the coupled machine 70 are driven jointly by the four energized electric machines 10, 20, 30, 40.

[0145] The procedure then returns to step S10.

[0146] If a corresponding state of the machine or drive system is detected in step S40 (S40: “N”), for example a drive power requirement which exceeds the first limit value but not the higher second limit value, the electric machine 30 is not energized, if necessary no longer, and for this purpose the switching device 34 is brought into its second operating state or held there, so that the electric machine 30 is or becomes actively short-circuited by this switching device 34 (step S60). Provided that it continues to be connected to the output in a torque-transmitting manner, since, for example, the switching unit 32 is not present or is in its first operating state, it is advantageously dragged along with low losses. Exemplary terminals 30A of the electric machine 30 are indicated in FIG. 1 for this purpose, which are short-circuited by the switching device 34 to thereby cause an active short-circuit of this electric machine.

[0147] Thus, all switching devices except the third switching device 34 are in their first operating state and the gear 51 or the coupled machine 70 are (only) driven jointly by the three electric machines 10, 20, 40.

[0148] The procedure then returns to step S10.

[0149] If a corresponding state of the machine or drive system is detected in step S20 (S20: “N”), for example a drive power requirement which also does not exceed the first limit value, the electrical machine 20 is not energized, or possibly no longer energized, and for this purpose the switching device 24 is brought into its second operating state or held there, so that the electrical machine 20 is or becomes actively short-circuited by this switching device 24 (step S70). If it continues to be connected to the output in a torque-transmitting manner, since, for example, the switching unit 22 is not present or is in its first operating state, it is advantageously dragged along with low losses.

[0150] Thus, all switching devices except the second and third switching devices 24, 34 are in their first operating state and the gear 51 or the coupled machine 70 are (only) driven jointly by the two electric machines 10, 40.

[0151] The procedure then returns to step S10.

[0152] Just as one or more, in particular all, switching devices can be omitted above for the embodiment in which (only) the switching devices are switched, conversely one or more, in particular all, switching units can be omitted for the embodiments explained at the beginning in which (only) the switching units are switched. Thus, in particular, in FIGS. 1, 2 one or more of the elements 12, 22, 32 and/or 42 and/or one or more of the elements 14, 24, 34 and/or 44 can be omitted.

[0153] In an embodiment, the two aspects explained above may also be or become combined.

[0154] Thus, for one or more of the machine units, both a switching unit and a switching device can be provided and used, in particular by actively short-circuiting the corresponding electric machine by means of the switching device in addition to an, in particular attempted, interruption of the torque-transmitting active connection of the transmission gear. In this way, safety can be increased in one embodiment.

[0155] Additionally or alternatively, only one switching unit can be provided and used for one or more of the machine units and only one switching device can be provided and used for one or more other of the machine units, so that the electrical machines are either actively short-circuited by corresponding switching devices or the torque-transmitting active connection of the associated transmission gear is interrupted by the corresponding switching unit, in particular when they are not required. In this way, it is advantageous, for example, to be able to “switch off” electrical machines that are differently constructed and/or used in different ways.

[0156] It should be noted that the exemplary embodiments are merely examples which are not intended to limit the scope of protection, the applications and the structure in any way. Rather, the preceding description provides the person skilled in the art with a guideline for the implementation of at least one exemplary embodiment, whereby various modifications, in particular with regard to the function and arrangement of the components described, can be made without leaving the scope of protection as it results from the claims and these equivalent combinations of features.

[0157] While the present invention has been illustrated by a description of various embodiments, and while these embodiments have been described in considerable detail, it is not intended to restrict or in any way limit the scope of the appended claims to such de-tail. The various features shown and described herein may be used alone or in any combination. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative example shown and described. Accordingly, departures may be made from such details without departing from the spirit and scope of the general inventive concept.

LIST OF REFERENCE SIGNS

[0158] 10; 20; 30; 40 Electric machine [0159] 30A Connection terminals [0160] 11; 21; 31 Transmission gearbox [0161] 12; 22; 32; 42 Switching unit [0162] 13; 23; 33; 43 Pinion [0163] 14; 24; 34; 44 Switching device [0164] 51 Gear [0165] 52 Output shaft [0166] 60 Control [0167] 61 Sensor [0168] 70 coupled machine [0169] 80 Power supply and/or energy storage device