In the field of mineral oil/natural gas production and especially in the maritime field, various production and/or process control systems are known, which each comprise a plurality of electrically operated devices. In addition to ducts, tubes, drill pipes and the like, such devices are attached in the area of a drilling and, as the case may be, also directly above a drill hole. The electrically operated devices comprise for example a well head device, a stand pipe connection device, various throttle and valves, blow-out-preventers or other preventers, which are especially employed as shut-off valves. Further electrically operated devices are also possible.

Lately, various corresponding hydraulically driven devices are being replaced by these electrically driven devices. For operating the respective devices, electric motors are required, wherein for reasons of redundancy, for each device also two or more electric motors may be provided. These serve for driving the corresponding actuators of the device, for example, in order to adjust a valve, to open or close a throttle or to move a preventer and especially its slider. Such electrically operated devices may have a number of advantages in comparison to hydraulically driven devices, such as a more simple installation, fewer corresponding lines, improved controllability and the like. However, a motor control is assigned to each of the electric motors, such that in a correspondingly big production and/or process control system, besides a plurality of electric motors, also a corresponding plurality of motor controls is employed. The corresponding motor controls may be centrally combined in the production and/or process control system indeed; however, a correspondingly high number of these controls is required.

For instance, if one considers a corresponding production system as an example of an electrical blow-out-preventer-drill-stack, the following requirements arise. For each electric motor of a blow-out-preventer, two motor controls are required in order to be able to generate a corresponding power as well as for redundancy reasons. As a general rule, a corresponding blow-out-preventer has four electric motors, so that also four respective motor controls are required. In a usual blow-out-preventer-drill-stack, besides the actual preventers, also other devices, such as valves and throttles are arranged, so that also without redundancy, already 20 motor controls are required at the minimum. With simple redundancy, already 40 motor controls are required. With such motor controls, it is to be considered that at least some of these are designed for high powers, such that the costs for the motor controls alone are very high. Therefore, it is an object underlying the invention to improve a corresponding electrical production and/or process control system to that effect that while having a simplified construction of the system, at the same time, a substantial reduction of the costs is possible without restrictions to redundancy requirements. This object is solved by the features of patent claim 1.

According to the invention, at least one multiple switching device is assigned to a motor control, such that by this combination of motor control and multiple switching device, a number of motor controls are replaceable. Due to the multiple switching device and motor controls assigned thereto, a number of electrically operated devices and the electric motors, respectively, are controlled and switched, respectively.

The multiple switching device has a switch housing, within which a plurality of contact elements arranged in contact groups are moveable. Each of the contact elements of a contact group when moved in axial direction, may separately be brought in electrical contact with a feed-in contact element. To each of the contact element groups, an output contact element for an electric motor for electrical supply is assigned. This means, for example, that three of such output contact elements are assigned to three electrical connections of only one electric motor, in order to supply the motor accordingly, while a further output contact element for example provides a holding voltage or alike for a corresponding electric motor. In this manner, the electric motor is supplied at all of its connections by different output contact elements, wherein one output contact element is provided by each contact element group. The corresponding contact elements of a contact element group are then useable for different electric motors, such that by only one multiple switching device a number of electric motors is controllable and suppliable. Thereby, the multiple switching device may also control a number of electric motors by only one open loop/closed loop motor control, when the electric motors may be assigned to different actuators or also to the same actuator. Thereby, the utilization of the multiple switching device takes place in the following manner. By a selection of certain contact elements of different contact element groups, for example, at first a blow-out-preventer (BOP) is moved into a certain position by supplying the assigned electric motor. Afterwards, further contact elements of the corresponding contact element group are selected, which are assigned to another electric motor of a different actuator in order to adjust it in a corresponding manner.

The further contact elements in each of the contact element groups may be used analogously to the control or driving of further electric motors of other actuators. Correspondingly, a gradual reset of the actuators takes place, for example in an initial position or a closed position. In order to achieve a compact construction, each of the contact elements may be essentially annular and contact elements of a contact element group may be arranged behind each other in axial direction.

In order to prepare contact element groups in a simple manner and to be able to modify them, every contact element group may be designed as an insertion module. This is inserted into a corresponding switch housing or withdrawn therefrom and replaced by another insertion module.

In order to be able to slide the corresponding contact element groups or insertion modules, respectively, together in a simple manner, the contact elements or the contact element groups, respectively, may be arranged in a contact piston, which is displaceable in an axial direction. This is supported moveably within the switch housing and the corresponding contact element groups may be insertable into the contact piston and may there be detachably fixed. An electric motor, especially a stepping motor, may thereby be assigned to the contact piston. The electric motor moves the contact piston into the corresponding positions. The movement of the contact piston by means of the electric motor may be carried out by a corresponding motor control, which, however, according to the present invention, is only provided singularly for a plurality of corresponding electrically operated devices. For example, a synchronous motor is utilizable, in which a rotor is turnable by a certain angular step or a multiple thereof by means of a stepwise rotating electromagnetic field of stator coils. Usually, there are 20 to 200 angular steps per turn, whereby a high turning precision and axial displaceability not only of the stepping motor but especially of the contact piston results.

In order to moveably couple the electric motor and the contact piston in a simple manner, the motor may be in a turning connection with a threaded spindle, which is assigned to the contact piston for displacement in axial direction.

In order to be able to arrange the corresponding insertion modules within the contact piston in a simple manner, the latter may have a plurality of insertion bores designed with an insertion opening which may be arranged especially annularly for the insertion of an insertion module each. Preferably, the insertion openings are arranged on one side of the contact piston, so that from this side, all corresponding insertion modules are insertable.

In order to be able to contact the different contact elements in a simple manner by the feed-in contact element, each of the insertion holes may have a through-bore opposing the insertion opening for slidably guiding a feed-in contact element therethrough. Under a corresponding displacement of the contact piston, the respective feed-in contact element displaces itself analogously within the through-bore and contacts the selected element of the respective contact element group.

In order to be able to make a good and secure contact with the respective contact element, the feed-in contact element may have a contact rod with a contact end section, which may be screwed onto the contact rod. Due to the utilization of such a contact rod, a certain inherent stiffness arises, such that the feed-in contact element may be slid through the corresponding opening in this region more simply.

The feed-in contact element with the contact rod and the contact end section are designed such that for instance 400 A or more may be transferred per contact for example without any problems.

For connecting the output contact element, it may prove advantageous if each of the contact elements is especially detachable connected to an output contact element. The output contact element extends from this connection point through the insertion opening of the contact piston belonging thereto towards the outside. The output contact elements of the contact elements of a contact element group may also be part of the insertion module. In this manner, this may be completely pre-manufactured from contact elements and output contact elements and may be inserted into corresponding insertion bores of the contact piston and attached there. A sufficient stability of the output contact elements results especially, when they are formed rod-like and are detachably affixed at a connection and at the contact element. For such a detachable fixation, various possibilities are conceivable, wherein, for example, the contact element may have a screw-in-bore for screwing in the connection end of the output contact elements.

Since each of the contact elements is connected to a output contact element, it may be regarded as advantageous if the output contact element extends from its corresponding contact element through openings of the others, which means all corresponding elements therebetween. Such an opening may be formed, for example, as an opening slit open towards the outside, through which the output contact element extends in an electrically isolated manner. In this manner, the corresponding outer dimensions of the contact element groups essentially correspond to the outer dimensions of the respective contact elements, such that this output contact element does not protrude radially towards the outside above the contact elements. Electrical insulation of an output contact element can, in this respect, be carried out relatively to the contact elements not belonging thereto, especially by an external coating. An example for such an external coating is a coating with polytetrafluoroethylene. Such a material further has a very small co-efficient of friction and a high specific resistance.

In order to prevent an electrical contact between the various contact elements as well, the contact elements of the contact element group may be electrically isolated with respect to the switch housing and/or with respect to each other and/or may be arranged at a distance to each other in axial direction.

The annular form of the contact elements may be especially used for the feed-in contact element. For example, during the displacement of the contact piston, the feed-in contact element assigned to a contact element group, respectively, may be displaceable through annular/circular openings of the contact elements of this group and may establish an electrical connection with its contact end section with the respectively selected contact element within the annular/circular opening.

Since the annular/circular opening or the inner surface of the annular/circular opening may contact the corresponding contact end section, as the case may be, only insufficiently for transferring high currents, a contact spring element may be supported within the annular/circular opening. Into this, the contact end section is slid and is sufficiently contacted by the contact spring element in order to be able to also transfer high currents. Of course, also the contact end section may have a contact spring section protruding radially and elastically towards the outside.

In a preferred embodiment, the contact spring element may be formed as a contact leaf spring element or insert. Such a thing at least extends sectionwise along the circumference of the corresponding opening.

In the beginning, it was already pointed out that in corresponding systems for mineral oil/natural gas production, redundancy is important with respect to the actuation of corresponding actuators and alike. In order to also achieve this in a multiple switching device according to the present invention, the electric motor may be designed to be redundant. An example for such a redundant designed is the arrangement of two independent stepping motors, wherein the one or the other is replaced in case of a failure. In this respect, also the possibility exists that the stepping motor is designed redundant in itself and may have two or more corresponding rotors, which are assigned to a stator. To determine the corresponding turning position of the threaded spindle or the axial position of the contact piston assigned thereto, at least one position sensor may be assigned to the stepping motor or the threaded spindle, respectively. Also, the possibility exists to assign a position sensor for determining the relative position of a feed-in contact element and at least a contact element to a feed-in contact element. Through the corresponding determination of the relative position, the other relative positions of the feed-in contact elements with respect to further contact elements may then be determined through capturing the rotation of the threaded spindle or the stepping motor.

In the following, advantageous embodiments of the invention are described in detail by using the drawing in the attached figures.

In the drawings: Fig. 1 : shows a principle illustration of an embodiment of an electric production and/or process control system;

Fig. 2: shows part of system according to Fig. 1 with a plurality of motor controls according to the prior art;

Fig. 3: shows the system according to Fig. 1 according to a second embodiment of the invention;

Fig. 4: shows a third embodiment of an electric production and/or process control system according to the invention;

Fig. 5: shows a fourth embodiment of an electric production and/or process control system according to the invention; Fig. 6: shows a perspective top view of an embodiment of a multiple switching device according to the present invention;

Fig. 7: shows a longitudinal section through the multiple switching device according to

Fig. 6;

Fig. 8: shows a perspective top view for a second embodiment of a multiple switching device in analogy to Fig. 6; and

Fig. 9: shows a longitudinal section through the embodiment according to Fig. 8 in analogy to Fig. 7. Fig. 1 shows a principle illustration of a first embodiment of a production and/or process control system 1 according to an embodiment of the present invention in the form of a maritime electric BOP-system. A number of electrically driven devices 2 are stacked above each other in the form of an eruption cross or Christmas tree. Such a stacking is also called a stack. In the illustrated embodiment, the respective stack is supplied redundantly, see the two control pods 39. Each of these control pods has a power supply 41 , a control unit 40 with a microprocessor, one or more motor controls 10, 11 , 12 or 13 as well as at least one multiple switching device 18, 19, respectively. The respective multiple switching device 18, 19, respectively, is assigned to the motor control 10, 1 1 and 12, 13, respectively. The multiple switching device is further described in the following with reference to Fig. 6.

The respective control pods 39 are connected to the electrically driven devices 2 via electric connection lines 16. Electrically driven devices are for example a well head device 3, a stand pipe connection device 4, various rams, preventers 8 or blow-out-preventers 7 as well as valves 6 and throttles 5. Corresponding electric motors are assigned to the valves and throttles 5, 6, respectively, for adjustment. Corresponding electric motors are also assigned to the other electrically driven devices 2, wherein also two or more of the electric motors may be arranged for adjustment for redundancy reasons. Also for redundancy reasons, two control pods 39 are provided, wherein the connection lines 16 illustrated as solid lines are the primary connection lines and the connection lines 17 not illustrated as solid lines are the respective secondary connection lines for redundancy.

As arising from Fig. 1 , only two motor controls 10, 1 1 and 12, 13, respectively, are provided wherein for example overall only four motor controls and two respective multiple switching devices are arranged for the entire construction already with redundancy. Thereby, the number of required motor controls is decreased, see for example Fig. 2, whereby both less space as well as especially fewer costs are required or incurred, respectively. With respect to the motor controls 10, 11 and 12, 13, respectively, it is to be noted that these are designed for supplying the electrically driven devices 2 having the highest power demands. For example, as a general rule, an actuator for a BOP requires about a 400 A, while a valve actuator, as the case may be, may require only 10 A. However, the respective motor control is designed in order to meet the highest power demand.

In comparison hereto, Fig. 2 shows the two control pods 39 which are employed without the respective multiple switching devices 18, 19 according to Fig. 1. The construction of the control pods 39 corresponds to that of Fig. 1 , except for the plurality of motor controls 10, 11 and 12, 13, respectively. Thereby, it is be considered that for each BOP for example, four motor controls are required, which are not all illustrated in Fig. 2. Under the same construction of the corresponding stacks, see Fig. 1 , 40 motor controls are required according to Fig. 2 and according to Fig. 1 , only four motor controls are required. Thus, the result is a substantial reduction of costs.

The rest of the lines leading from the control pods 39 correspond to each other in Figs. 1 and 2, wherein a line 44 serves for an electrical operation of a remotely operated vehicle (ROV) and a further line 45 serves as an electric signaling line in case of an emergency. Furthermore, there is a kill line 14 and a choke line 15. The respective control pods 39 may also be realized in the form of electric control modules on the bottom of the sea. These are generally called ESCM (electrical subsea control module). Fig. 3 shows respective control pods 39 for a second embodiment according to the present invention. Except for the parts shown in Fig. 3, the construction of the production and/or process control system 1 according to Fig 3 corresponds to that of Fig. 1. A control unit 40 as well as a motor control 10 and 1 1 , respectively, is provided in the respective control pod 39. A corresponding power supply 41 and a multiple switching device 18 are assigned to the two control pods 39. The multiple switching device 18 is operable according to the respective requirements from one of the control pods 39. The rest of the electrical lines correspond to those of Fig. 1.

In a construction according to Fig. 3, in comparison to Fig 1 , two motor controls and one multiple switching device less are required. Thereby, when omitting redundancy with respect to some of the units, further costs are saved.

Fig. 4 shows another embodiment of a production and/or process control system according to another embodiment of the present invention. This serves for an electric tree-control system for example with two redundant control pods 39. The control pods 39 again are connected to actuators 46 via respective electrical lines 16, 17. These are actuated and supplied by respective settings of the multiple switching device 18, 19 and control and adjust the assigned electrically driven devices 2 in the form of valves, throttles and alike on their own accord.

The control pods 39, analogously to the Figs. 1 and 3, further have a power supply 41 and a control unit 40 with a microprocessor. Furthermore, two motor controls 10, 11 and 12, 13, respectively, are arranged within every control pod 39. The motor controls 11 and 13 serve for a direct control of an actuator, see the direct electrical connection line between the motor control 11 and 13 and the respective actuator on the right outer side in Fig. 4. An emergency bypass line 47 is assigned to each of the multiple switching devices 18, 19, via which, as the case may be, by bridging or bypassing of the multiple switching devices, a corresponding supply of at least one or a number of the actuators is possible.

The construction of the system according to Fig. 4 is redundant, see the double arrangement of the control pods and the double arrangement of the corresponding electrical lines 16 and 17, respectively.

The construction of such a system may further be facilitated in that a maximum possible number of actuators is used, which for example, are automatically arranged in their safety position during failure of an electric supply, such that an electric holding in this safety position is not necessary. Such a safety position is a closed position of a respective valve for example or a closing of a BOP.

In Fig. 5, a third embodiment of a production and/or process control system according to the present invention is illustrated. Overall, a number of corresponding trees are supplied by two control pods 39. The construction of the control pods 39 essentially corresponds to that of Fig. 4, wherein the control pod arranged at the right side of Fig. 5 overall has three motor controls 13 for redundant supply, which are directly connected to respective actuators 46 without interposition of a multiple switching device 19. The rest of the motor controls 10, 11 , 12 are assigned to the multiple switching devices 18 and 18, respectively, wherein between these, a multiple power supply 48 is arranged, see also Fig. 4. This multiple power supply 48, according to the multiple switching devices 18, 19 has a matching number of terminals.

Furthermore, a ROV-terminal 49 is assigned to each of the control pods 39.

Moreover, it is also be considered in all embodiments that the respective control pods may be connected to devices at the surface of the sea or also with further central control devices on the bottom of the sea. With respect to the motor controls which are connected to the multiple switching devices 18, 19, it is further noted that they serve for controlling corresponding throttles are alike by means of a PID-control (proportional-integral-derivative controller).

In the following, two embodiments of respective multiple switching devices 18, 19 are described in detail by reference to Figs. 6 to 9 according to the preceding figures. Each of the same of the same parts are indicated by the same reference signed and are only partly explained in connection with one of the figures. The multiple switching device has an electric drive in the form of a stepping motor 26. This is detachably fixed to an end of a switch housing 20. The switch housing 20 is formed pot-shaped and a contact piston 25 is moveably supported in the switch housing 20. In the Figs. 6 and 7, the contact piston is exerted or pushed out and in Figs. 8 and 9 it is inserted or pushed in. The stepping motor 26 may have a positioning sensor 39, which captures a corresponding turning position of the stepping motor and may convert it into an adjustment of a threaded spindle 27 connected to the stepping motor. The threaded spindle 27 extends to a central hole or bore 30 of the contact piston 25. At an end of the contact piston 25 assigned to the threaded spindle 27, a threaded member 28 is arranged. Within this, the threaded spindle 27 is rotatably supported and in engagement with a corresponding thread. By turning the threaded spindle 27, the contact piston 28 is analogously adjusted in axial direction.

At an end of the switch housing 20 assigned to the stepping motor 26, a number of feed-in contact elements 23 radially extend towards the exterior essentially in the form of an L. With an end arranged within the switch housing 20, these feed-in contact elements 23 are connected to a contact rod 29. This is located stationary within the contact housing 20, wherein during an adjustment of the contact piston 25 in axial direction, the respective relative displacement of the contact rod 29 with respect to a number contact elements 22 is achieved. The contact elements 22 are formed essentially annular and have an inner hole, wherein the contact rod 29 is slidably arranged. Each of the contact elements 22 is connected to an output contact element 24. These may be connected to further electrical connecting devices, such as electrical lines or alike. The respective output contact elements 24 are in electrical connection with electric lines 16 and 17, respectively, according to the proceeding figures.

The output contact elements are pooled as various contact element groups 21 , see Figs. 6 and 7, wherein the corresponding contact element group 21 is assigned to a number of contact elements 22, respectively, see for example Figs. 7 and 9. The different output contact elements

24 are inserted into the contact piston 25 through an insertion opening 31 of the contact piston

25 and thereby in connection with the assigned contact element 22. This connection may be made for example by threading in a connection end 32 of each of the output contact elements 24 into a thread within in the hole 33 of the contact elements 22 assigned thereto. In the illustrated embodiment, the feed-in contact elements 23 of the different contact element groups 21 are arranged concentrically around the threaded spindle and the central hole 30 of the contact piston 25. On the end of the contact rod 29 facing the contact elements 22, the contact rod 29 has a contact end section 34. This may be formed by a contact device which is screwed onto, (see Fig. 7) or held by the contact rod, (see Fig. 9). With a corresponding adjustment of the contact rod in axial direction, the contact end section 34 comes into contact with the respective contact element 22 from the inside and establishes an electrical connection between the feed-in contact element 23 and the output contact element 24.

In order to be able to establish a contact between the contact end section 34 and the contact element 22 in a improved way, a contact spring element 35 may be arranged within the respective contact element 22. Also the possibility exists that a contact element elastically facing towards the exterior is arranged at the contact end section 34 of the contact rod 29, see Fig. 9.

In the embodiments according to Fig. 8 and 9, additionally a mounting wall plate 37 is provided at which the contact piston 35 with its front side is detachably fixed in a one-sided manner. The mounting wall plate 37, as the case may be, may have a vertically extending bottom plate, which serves for mounting the respective multiple switching device 18 and 19, respectively, at the control pod 39 or another device of the position and/or process control system.

For an electrical insulation, each of the respective output contact elements 24 has an exterior coating of polytetrafluoroethylene for example, i.e. an exterior coating with a high specific resistance. In this manner, an electric contact between the output contact element and the contact elements not belonging thereto is prevented.

For saving room, the various contact elements 22 have openings, which are open in radial direction towards the outside or are also closed, through which the output contact elements 24 are guided into the interior of the contact piston 25 to their associated assigned contact element 22. Further, the possibility exists that for example output contact elements 24 belonging to the contact elements 22 of the respective contact element groups 21 may be handled as a replaceable module which is insertable into the respective insertion opening 31 of the contact piston 25. In this manner, a simple adjustment to corresponding electrically operated devices and their number of terminals may be achieved. One output contact element of a corresponding contact element group each is assigned to a terminal of a corresponding electric motor of the electrically operated device, such as in the illustrated embodiment, see Figs. 6 and 8, at the maximum five output contact elements 24 are provided for an electric motor. By a respective displacement of the contact piston 25, in each of the contact groups, a corresponding contact element is electrically contacted and via the assigned output contact element of each of the contact element groups, an electric motor is supplied. If afterwards, the contact piston is moved into another position, then five other output contact elements are brought into contact with the feed-in contact elements assigned thereto and via the associated output contact elements, another electric motor is supplied.

There also exists the possibility that in each of the contact element groups or at least that some of these, certain contact elements are not directly connected to an electric motor but with another multiple switching device. In this manner, a multiple switching device may supply a further multiple switching device which also may have five feed-in contact elements. Besides that, there is the possibility that by a contact element of one or more contact element groups, data is transferred to subsequent devices. The number of contact element groups, the number of contact elements arranged in each contact element and analogously the number of the output contact elements is variable and also different numbers of contact elements and output contact elements may be employed at a multiple switching device.

The corresponding positioning sensor also serves for precisely determining or capturing which of the corresponding contact elements is connected to the associated feed-in contact element 23 by positioning the contact rod 29. Again it is pointed out that according to the present invention, the multiple switching device is utilized for supplying multiple electric motors of actuators by means of only one feed forward/feed back motor control. In the illustrated embodiment, eight electric motors with five terminals are each are suppliable, see the five feed-in contact elements as well as the eight output contact elements assigned to each feed-in contact element. An output contact element of each of the contact element groups may thereby be assigned to a terminal of an electric motor and, by the corresponding output contact elements of each of the contact groups, over five terminals of this electric motor are suppliable. Thereby, for example, three output terminals may be connected to the respective windings of the electric motor, while the other two output contact elements may for example generate a holding torque of the electric motor or may provide a DC emergency power supply.