Connection Connector for Drive Units

A drive system having a plurality of drive units that each have a converter and preferably one motor, wherein the drive system includes an energy supply system that supplies electric energy to the drive units, and a control system that includes a control computer and at least one control line, where the control system transmits control instructions to the drive units, and where the energy supply system and the drive units are releasably connected together via a first respective connection connector, preferably via a plug connection, and the control system and the drive units are releasably connected together via a second respective connection connector, preferably via a plug connection.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a drive system having a plurality of drive units, relates to a connection connector for a drive system and relates to a method for producing and separating a connection of the drive unit to an energy supply system and a control system.

2. Description of the Related Art

In the case of decentralized drive systems having a plurality of drive units, such as in the case of conveyor belts, it was previously necessary to shut down the entire drive system in the event of exchanging an individual drive unit. In this case, the entire installation comes to a standstill, which is to be avoided.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a drive system having a plurality of drive units in which a simple exchange of individual drive units is possible without it being necessary for this purpose for the entire drive system to come to a standstill.

This and other objects and advantages are achieved in accordance with the invention by a drive system having a plurality of drive units, by a connection connector, and by a method for producing and separating a connection of the drive unit.

The drive system in accordance with the invention comprises a plurality of drive units, where the drive units each comprise at least one inverter and one motor. The drive system moreover has an energy supply system that is configured to supply the drive units with electrical energy, and a control system that comprises a control computer and at least one control line, where the control system is configured to transmit control instructions to the drive units.

The drive system is characterized by virtue of the fact that the energy supply system and the drive units are each connected to one another in a detachable manner via a first connection connector, preferably via a plug connection, and that the control system and the drive units are each connected to one another in a detachable manner via a second connection connector, preferably via a plug connection.

With the aid of the inverter, for example, it is possible to control and/or regulate a motor that is connected to the inverter. Here, the inverter can specify, for example, a voltage amplitude or a voltage frequency with which the motor is influenced. The motor can be, for example, an electric motor.

The energy supply system can be an arbitrary voltage source (stationary or mains driven) that can each supply the motor via the inverter of a drive unit with electrical energy in order to render possible an intended use of the motor. The electrical energy supply system is configured to supply a plurality of drive units and is dimensioned accordingly in terms of its power capacity.

The control computer can be any arbitrary computing unit that is configured to generate control commands to the inverter and/or the motor of a respective drive unit and to transmit these control commands to the drive units via a control line, for example, a copper line or a fiber optic.

Drive units having integrated inverters (and where applicable motors) offer the possibility of reducing the external connections to a minimum because, for example, temperature sensors or position encoders can be realized internally. The drive unit only has one connection to the energy supply system and to the control system. In the case of the connection to the energy supply system, it is possible to be a direct current voltage or an alternating current voltage connection (two-phase or three-phase). The connection to the control system can be, for example, purely optical, without an electrical connection existing.

The invention is based on the idea that a detachable connection between the individual drive units and the central energy supply and also controller renders it possible to exchange individual (possibly defective or to be refurbished) drive units without the shut-down of the entire drive system being necessary for this purpose. As a consequence, for example, multiple drive units are connected one behind the other in the drive system (which is regularly applied, for example, in the case of conveyor belts) without an interruption of the operation of the remaining drive units being necessary for the exchange of the drive unit. The first connection connector and the second connection connector in this case remain in the drive system and ensure the proper operation.

The drive unit can also be a combination of an inverter having a photovoltaic unit, such as a solar cell. The advantages of the drive system in accordance with the invention come into effect here in the event of a photovoltaic unit (or the inverter) that is to be repaired or exchanged because it is not necessary to shut down the remaining drive units for this purpose (for example, in the context of a photovoltaic installation having a plurality of photovoltaic units (all inverters)).

The first connection connector and the second connection connector are preferably formed as a common connection connector in order to improve the manageability.

It is preferred that the common connection connector is configured such that, in the event of a detachment of the connection of the common connection connector to the drive unit, the connection between the control system and the drive unit is separated chronologically prior to the connection between the energy supply system and the drive unit. Due to the previous separation of the connection of the drive unit to the control system, the motor or the inverter can be prepared for the impending voltage drop that accompanies the subsequent separation of the connection of the drive unit to the energy supply system. This can generally also be performed manually by a maintenance technician in the case of separated connection connectors (first and second connection connectors). The corresponding configuration of the (common) connection connector however furthermore brings the advantage that the sequence of separating the connection is performed automatically in an electrically advantageous sequence (without causing arcing or the like).

Within the scope of a preferred embodiment of the invention, the first connection connector, the second connection connector or the common connection connector and the drive unit respectively have a complementary connection for an energy supply of the drive unit via a DC voltage power supply and in addition a respective complementary connection for pre-charging the inverter of the drive unit. A pre-charge of the inverter can lead in a manner known per se to a reduction of current peaks as the connection of the inverter to the energy supply system is being produced and thus a destruction or an excessive degeneration of parts of the inverter can be avoided.

It is particularly preferred that the first connection connector and/or the second connection connector or the common connection connector have a detachable connection to the energy supply system and/or to the control system. As a consequence, it is possible to remove a drive unit together with the associated connection connector in a simple manner from an existing drive system or to add a drive unit to an existing drive system. The above-described detachable connections are preferably plug connections, i.e., a connection that comprises a plug and an associated corresponding recess.

The drive system can be configured such that multiple operating steps must be performed in a predetermined sequence to detach the detachable connection or the detachable connections. This brings the advantage that an accidental detachment of the connection (s) can be avoided.

In this case, the inverter and/or the first connection connector and/or the second connection connector and/or the common connection connector can have locking arrangements based on levers and/or leading contacts and/or magnetic locking arrangements such that the multiple operating steps must be performed in the predetermined sequence to detach the detachable connection or the detachable connections. As a consequence, it is possible to specify in a particularly simple and efficient manner the required sequence of the steps that are to be performed.

In one advantageous embodiment of the invention, the drive unit and/or the first connection connector and/or the second connection connector and/or the common connection connector have an optical element, in particular a light-emitting diode, and it is possible to signal via the light-emitting diode that a pre-charging procedure of the inverter has been terminated or a defined state of the drive unit has been reached. An installer of the drive system as a consequence receives information regarding, for example, whether the inverter is ready for connecting the main (energy) supply following the pre-charging procedure. Alternatively, they receive a message regarding whether the connection of the drive unit to the energy supply system can be separated.

The first connection connector and/or the second connection connector or the common connection connector can have a filter element, in particular a capacitor, and/or a shielding in order to increase an electromagnetic compatibility of the connection connector. Measures of this type are likewise possible in the case of the inverter and/or the motor. In addition, measures can be provided on the connections of the connection connector (first, second and/or common), which can protect the electrical contacts of the connection connector against arcing (for example, in the form of a permanent magnet (blowout) or by a corresponding circuitry of the contacts).

The objects and advantages in accordance with the invention are moreover achieved by a connection connector for a drive system in which the connection connector is configured such that, in the event of a detachment of the connection of the common connection connector to the drive unit, the connection between the control system and the drive unit is separated chronologically prior to the connection between the energy supply system and the drive unit.

The connection connector cannot merely be used for a drive system. It is also possible to use the connection connector for a combination of an inverter with a current generating unit, such as a photovoltaic unit.

Advantageously, the connection connector in this case has a connection to the energy supply system and/or to the control system.

It is particularly preferred that the connection connector has a connection, which is complementary to the drive unit, for an energy supply of the drive unit via a DC voltage power supply and in addition has a complementary connection for pre-charging the inverter of the drive unit.

The objects and advantages in accordance with the invention are moreover achieved by a method for producing and separating a connection of a drive unit, which comprises an inverter (and preferably a motor), to an energy supply system that is configured to supply the drive unit with an electrical energy and to a control system that comprises a control computer and at least one control line, where the control system is configured to transmit control instructions to the drive unit. The method comprises:a) producing a connection of the drive unit to the energy supply system and to the control system by a common connection connector;b) signaling to the drive unit that a separation from the energy supply system is impending, where the signaling is preferably performed by a separation of the connection of the drive unit to the control system; andc) subsequently separating the connection of the drive unit to the energy supply system by separating the connection of the drive unit to the connection connector.

In this case, during method step a) initially a connection of the energy supply system to a pre-charging connection of the drive unit is preferably produced via the connection connector in order, as described above, to prevent excessively high current peaks and a thus associated wear/destruction of the drive unit.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG.1illustrates a drive system1that has a plurality of drive units of which, for purposes of clarity, only one single drive unit2is illustrated. At least one further (not illustrated) drive unit of the drive system1is configured in an essentially identical manner to the drive unit2that is illustrated inFIG.1. The drive unit2has an inverter3and a motor4.

The drive system1furthermore comprises an energy supply system5and a control system6. The energy supply system5is configured to supply the drive unit2with electrical energy via power lines7a,7b(here via a DC voltage power supply). The control system6has a control computer8and a control line9.

The energy supply system5and the drive unit2are connected to one another in a detachable manner via a connection connector10. For this purpose, the connection connector10has a first connection11and a second connection13that are each formed as a plug or pin.

The first connection11of the connection connector10is configured such that the first connection11can be plugged into a first connection12of the drive unit2, where the first connection12is formed as a socket. It is possible via the first connection11,12to transfer an electrical energy so as to drive the motor4(main energy supply) from the energy supply system5to the drive unit2.

The second connection13of the connection connector10is configured such that the second connection13can be plugged into a second connection14of the drive unit2, where the second connection14is also formed as a socket. It is possible via the second connection13,14to transfer an electrical energy so as to pre-charge the inverter3of the drive unit2(pre-charging energy supply) from the energy supply system5to the drive unit2. Typically, the connections13,14for the pre-charging are dimensioned as smaller, i.e., the connections11,12for the main energy supply.

The connection connector10moreover has a third connection15that is formed as a plug or pin and can be plugged into a corresponding connection16of the drive unit2, where the corresponding connection16is formed as a socket. The control system6can be connected in a detachable manner via this connection15,16to the drive unit2. The connection is made in the current example via a fiber optic as a control line9.

A method for producing and separating a connection of the drive unit2to the energy supply system5and to the control system6can be performed as follows. The connection connector10that has a connection to the energy supply system5and the control system6is connected to the drive unit2. For this purpose, the plugs of the second connection13are formed longer than the plugs of the first connection11, which is apparent inFIG.1. As the connection connector10is being plugged into the drive unit2(or more precisely: the plug of the connections11,13,15into the corresponding connections12,14,16of the drive unit2) due to this configuration of the plugs13the connection for the pre-charging of the drive unit2is produced earlier than the connection to the main energy supply of the motor4(this is also referred to as “leading contacts”). As a consequence, pre-charging of the inverter3is automatically rendered possible without an installer needing to take any particular care for this purpose which brings with it the advantages that are already described above with regard to the durability and wear of the drive unit2. The drive unit3can signal via a light-emitting diode17as an optical element (or optically operating element) that the pre-charging process has been terminated.

In a subsequent step, the drive unit2signals that the connection is again to be separated (for example, in the event of a planned exchange of the drive unit2). For this purpose, the control computer8can transmit a signal to the drive unit2that causes a transfer of the motor4or the inverter3into a safe state. It is, however, alternatively also possible for the connection of the drive unit2to the control system6to be separated, for example, by a corresponding configuration of the connections15,16of the connection connector10or the drive unit2. These can be configured so that, in the event of the connection connector10being disengaged/detached from the drive unit2, the control connection is separated first (in particular prior to the connections11,12of the main energy supply). In other words, the connection connector2in this case is configured in manner that in the event of the connection of the connection connector10to the drive unit2becoming detached, the connection between the control system6and the drive unit2is separated chronologically prior to the connection between the energy supply system5and the drive unit2.

Subsequently, the connection of the drive unit2to the energy supply system5is interrupted due to a separation of the connection of the drive unit2to the connection connector10(due to the connection connector10being pulled out of the drive unit2). Alternative ways to prepare the drive unit2are also possible, one of which is explained with the aid ofFIG.3.

FIG.2illustrates a connection connector10and an associated drive unit2. The drawing is simplified with respect toFIG.1and only represents the aspect that specific operating steps must be performed in a predetermined sequence to detach the connection between the connection connector10and the drive unit2. The drive unit2, for this purpose, has an (electro) magnetic locking arrangement18that can move a pin19along an axis. The connection connector10has a bolt20that is inserted into a recess21of the drive unit2as the connection connector10is being connected to the drive unit2. A recess22is located in the bolt20and the pin19can be inserted by the locking arrangement18into the recess as the connection connector10is being connected to the drive unit2. The bolt20can consequently no longer move downward (in the drawing plane) with the result that the connection connector10and drive unit2are secured against one another. If the intention is to detach the connection, then the locking arrangement18receives a corresponding control command (via the control system6or by a manual operation on the drive unit2) and moves the pin19out of the recess22with the result that the connection connector10can subsequently be removed. As a consequence, the drive unit2has sufficient time to prepare for the separation of the energy supply system5.

FIG.3illustrates an alternative embodiment of a connection connector10. Here, the connection15for connecting the control system6to the drive unit2is configured so that it can be displaced against the connections11,13for the energy supply. For this purpose, it is possible to use a locking arrangement that is based on a lever23. Due to this configuration of the connection connector10, it is possible to ensure that initially the connection of the drive unit2to the control system6is interrupted in order to signal to the drive unit2an impending separation of the connection to the energy supply system5.

InFIG.4, the drive unit2has an internal controller24that can either be addressed directly (via a button or the like) or via the control system6. The controller24can trigger an apparatus25that acts magnetically and that can move a locking lever26of the connection connector10between a locking position and a detaching position via a magnetic pulling force. As a consequence, it is possible to ensure that the connection of the drive unit2to the connection connector10cannot be detached unintentionally.

FIG.5is a flowchart of the method for producing and separating a connection of a drive unit2, which comprises an inverter3and a motor4, to an energy supply system5that supplies the drive unit2with electrical energy and to a control system6that comprises a control computer8and at least one control line9, where the control system (6) is configured to transmit control instructions to the drive unit2.

The method comprises a) producing a connection of the drive unit2to the energy supply system5and to the control system6by a common connection connector10, as indicated in step510.

Next, b) the drive unit2is signaled that a separation from the energy supply system5is impending, as indicated in step520. In accordance with the method, the signaling is performed by a separation of the connection of the drive unit10to the control system6.

Next, c) the connection of the drive unit2to the energy supply system5is subsequently separated by separating the connection of the drive unit2to the connection connector10, as indicated in step530.