Device for conveying thick matter

Abstract

The invention relates to a device (100) for conveying thick matter, comprising: an electric motor (1), a DC voltage intermediate circuit (2), a first AC voltage connection (16), which can be coupled to a first AC voltage supply (4), a first rectifier (3) which rectifies voltages present at the first AC voltage connection (16), an electrical energy store (5), a first galvanically isolating DC / DC converter (6), which can be switched between the DC voltage intermediate circuit (2) and the electrical energy store (5) depending on the operating mode, and which is designed for bidirectional transmission of electrical power between the DC voltage intermediate circuit (2) and the electrical energy store (5), and an inverter (7) supplied from the DC voltage intermediate circuit (2), which is designed to control the electric motor (1), wherein an electrical power that can be transmitted in the direction of the electric motor (1) by means of the inverter (7) is greater than an electrical power that can be transmitted between the DC voltage intermediate circuit (2) and the electrical energy store (5) by means of the galvanically isolating DC / DC converter (6).

Description

[0001] Device for conveying thick material

[0002] The invention is based on the objective of providing a device for conveying thick material that enables the most flexible operation possible on an AC power network.

[0003] The device for conveying thick material has one or more conventional electric motors, for example in the form of three-phase motors.

[0004] The device for conveying thick material also features a conventional DC intermediate circuit.

[0005] The device for conveying thick material further has a first AC voltage connection which can be coupled to a first, for example three-phase, AC voltage network.

[0006] The device for conveying thick material further comprises a first rectifier that rectifies the voltages present at the first AC voltage connection and outputs them, for example, to the DC link. The first rectifier can be active or passive. The first rectifier may also include, for example, a boost converter.

[0007] The device for conveying thick material also includes an electrical energy storage device, for example in the form of a rechargeable battery storage device.

[0008] The device for conveying thick material further comprises a first galvanically isolated DC / DC converter, which, depending on the operating mode, can be switched between the DC link and the electrical energy storage device, or is not switched between the DC link and the electrical energy storage device. If switched, the converter serves to transfer electrical power, particularly bidirectionally, between the electrical energy storage device and the DC link. The voltage level on the DC link can, for example, be between 400 V and 800 V. The typical voltage present at the electrical energy storage device can also be between 400 V and 800 V, but can also be significantly lower, for example, approximately 100 V.

[0009] The device for conveying thick material further comprises a conventional inverter fed from the DC link, which is designed to drive the electric motor. The electrical power transferable to the electric motor via the inverter is greater than the electrical power transferable between the DC link and the electrical energy storage device via the galvanically isolated DC / DC converter, for example by a factor of 1.2 to 10, and in particular by a factor of 1.5 to 3.

[0010] The device for conveying thick material is in particular a (vehicle) concrete pump.

[0011] In one embodiment, the device for conveying thick material further comprises: a second AC voltage connection which can be coupled to the first AC voltage network or a second AC voltage network.

[0012] In one embodiment, the device for conveying thick material is designed to transfer electrical power from the second AC voltage connection, depending on the operating mode, in particular directly, either towards the electrical energy storage device or towards the DC intermediate circuit.

[0013] In one embodiment, the device for conveying thick material is designed to transfer electrical power, depending on the operating mode, either from the second AC voltage connection to the DC intermediate circuit or to the electrical energy storage device, or to transfer power between the DC intermediate circuit and the electrical energy storage device.

[0014] In one embodiment, the device for conveying thick material is designed to electrically connect the electrical energy storage device to the DC link, depending on the operating mode, without the intermediate of the first galvanically isolating DC / DC converter, in particular directly.

[0015] In one embodiment, the device for conveying thick material is designed to either supply the DC intermediate circuit from the rectified voltage of the first rectifier, depending on the operating mode, or to supply the first galvanically isolated DC / DC converter from the rectified voltage of the first rectifier.

[0016] In one embodiment, the device for conveying thick material further comprises: a second rectifier that rectifies the voltages present at the second AC voltage connection, and a second galvanically isolated DC / DC converter with a first connection and a second connection that can be supplied or is supplied from the rectified voltage of the second rectifier. The second rectifier and the second galvanically isolated DC / DC converter can be part of a so-called on-board charger (OBC).

[0017] In one embodiment, the device for conveying thick material further comprises: a first controllable switching device, for example in the form of a contactor, which, depending on its switching position, electrically connects the second terminal of the second DC / DC converter either to the DC link or to the electrical energy storage device.

[0018] In one embodiment, the device for conveying thick material further comprises: a second controllable switching device, for example in the form of a contactor, which, depending on its switching position, electrically connects the first terminal of the second DC / DC converter either to the second rectifier or to the electrical energy storage device.

[0019] In one embodiment, the device for conveying thick material has a first operating mode during which electrical power from the first AC network and the electrical energy storage is transferred towards the electric motor, a second operating mode during which electrical power from the first AC network is transferred towards the electrical energy storage and towards the electric motor, and a third operating mode during which electrical power from the first AC network is transferred exclusively towards the electrical energy storage.

[0020] In one embodiment, the device for conveying thick material has a number of hydraulic pumps, for example between one and ten hydraulic pumps, which are driven by the electric motor.

[0021] In one embodiment, the device for conveying thick material has a number of hydraulic cylinders, for example between one and twenty hydraulic cylinders, which are supplied by one or more of the number of hydraulic pumps.

[0022] In one embodiment, the device for conveying thick material further comprises: a second rectifier that rectifies the voltages present at the second AC voltage terminal, a second galvanically isolated DC / DC converter with a first terminal and a second terminal, a first controllable switching device, a second controllable switching device, and a third controllable switching device, wherein the first controllable switching device, depending on its switching position, electrically connects the DC link either to the second terminal of the second galvanically isolated DC / DC converter or to a first terminal of the first galvanically isolated DC / DC converter, wherein the second controllable switching device, depending on its switching position, electrically connects the first terminal of the second DC / DC converter either to the first terminal of the first galvanically isolated DC / DC converter or to the second rectifier.and wherein the third controllable switching device, depending on its switching position, electrically connects the first rectifier either to the DC link or to the first terminal of the first galvanically isolated DC / DC converter.

[0023] In one embodiment, the first galvanically isolated DC / DC converter is a 4-quadrant converter and / or the inverter is a 4-quadrant inverter.

[0024] The invention is described in detail below with reference to the drawings.

[0025] This shows:

[0026] Fig. 1 schematically shows an electrical block diagram of a device for conveying

[0027] Thick material according to a first embodiment,

[0028] Fig. 2 schematically shows an electrical block diagram of a device for conveying thick material according to a second embodiment,

[0029] Fig. 3 schematically shows an electrical block diagram of a device for conveying thick material according to a third embodiment and

[0030] Fig. 4 schematically shows an electrical block diagram of a device for conveying

[0031] Thick material according to a fourth embodiment.

[0032] Fig. 1 schematically shows an electrical block diagram of a device 100 for conveying thick material according to a first embodiment.

[0033] The device 100 for conveying thick material comprises: an electric motor 1, a DC link 2, a first AC connection 16 which can be coupled to a first AC network 4, a first rectifier 3 which rectifies voltages present at the first AC connection 16 and outputs them to the DC link 2, a rechargeable electrical energy storage device 5, a first galvanically isolated DC / DC converter 6 which is connected between the DC link 2 and the electrical energy storage device 5 and which is designed for bidirectional transmission of electrical power between the electrical energy storage device 5 and the DC link 2, an inverter 7 supplied from the DC link 2 which is designed to control the electric motor 1, and, by way of example, a hydraulic pump 14 which is driven by the electric motor 1.and, by way of example, a hydraulic cylinder 15, which is supplied by means of the hydraulic pump 14.

[0034] Furthermore, a main switch 18 is provided, which is conventionally used for all-pole network disconnection.

[0035] The electrical power that can be transferred to the electric motor 1 via the inverter 7, for example 300 kW, is greater than the electrical power that can be transferred between the DC link 2 and the electrical energy storage device 5 via the galvanically isolated DC / DC converter 6, for example 80 kW. Therefore, the DC / DC converter does not need to be dimensioned for the full rated power of the electric motor 1 or the inverter 7.

[0036] Fig. 2 schematically shows an electrical block diagram of a device 100 for conveying thick material according to a second embodiment.

[0037] The device 100 for conveying thick material according to the second embodiment further comprises a second AC voltage connection 17, which can be connected to the first AC voltage network 4 or a second AC voltage network 9. The second embodiment is designed to transfer electrical power from the second AC voltage connection 17, depending on the operating mode, either directly towards the electrical energy storage device 5 or directly towards the DC intermediate circuit 2.

[0038] For this purpose, the device 100 for conveying thick material according to the second embodiment further comprises: a second rectifier 8, which rectifies voltages present at the second AC voltage connection 17, a second galvanically isolated DC / DC converter 10 with a first connection 10a and a second connection 10b, which is supplied from the rectified voltage of the second rectifier 8, and a first controllable switching device 11, which, depending on its switching position, electrically connects the second connection 10b of the second DC / DC converter 10 either to the DC voltage intermediate circuit 2 or to the electrical energy storage device 5.

[0039] Fig. 3 schematically shows an electrical block diagram of a device 100 for conveying viscous material according to a third embodiment. This device further comprises a second controllable switching element 12, which, depending on its switching position, electrically connects the first terminal 10a of the second DC / DC converter 10 either to the second rectifier 8 or to the electrical energy storage device 5. This makes it possible, depending on the operating mode, to transfer electrical power either from the second AC terminal 17 to the DC link 2 or to the electrical energy storage device 5, or to connect the second DC / DC converter 10 in parallel to the first DC / DC converter 6 in order to transfer more energy between the DC link 2 and the electrical energy storage device 5.

[0040] Fig. 4 schematically shows an electrical block diagram of a device 100 for conveying thick material according to a fourth embodiment. This embodiment is designed to electrically connect the electrical energy storage device 5 to the DC link 2, depending on the operating mode, without the intermediate of the first galvanically isolated DC / DC converter 6, in particular directly.

[0041] Furthermore, depending on the operating mode, it is possible either to supply the DC intermediate circuit 2 from the rectified voltage of the first rectifier 3, or to supply the first galvanically isolated DC / DC converter 6 from the rectified voltage of the first rectifier 3.

[0042] For this purpose, the device 100 for conveying thick material according to the fourth embodiment has a third controllable switching means 13, wherein the first controllable switching means 11, unlike in Fig. 2 and Fig.3 shown, depending on its switching position, electrically connects the DC link 2 either to the second terminal 10b of the second galvanically isolated DC / DC converter 10 or to a first terminal 6a of the first galvanically isolated DC / DC converter 6, wherein the second controllable switching device 12, depending on its switching position, electrically connects the first terminal 10a of the second DC / DC converter 10 either to the first terminal 6a of the first galvanically isolated DC / DC converter 6 or to the second rectifier 8, and wherein the third controllable switching device 13, depending on its switching position, electrically connects the first rectifier 3 either to the DC link 2 or to the first terminal 6a of the first galvanically isolated DC / DC converter 6.

[0043] The embodiments shown in Figures 2 to 4 each have a second AC voltage connection 17, which can be connected to a second AC voltage network 9. It is understood that, in addition to the second AC voltage connection 17, further AC voltage connections and downstream components such as rectifiers, switching devices, and DC / DC converters may be present, which are then connected according to the power paths of components 8, 10, and 12. The potentials of the electrical energy storage device or battery 5 should be galvanically isolated from the network potential. According to the invention, this galvanic isolation is achieved with low power between the DC link 2 and the electrical energy storage device 5, since the main drive power is not routed through this galvanic isolation. Power electronics without galvanic isolation are cheaper, smaller, and more efficient. In this way, the device 100 also becomes more efficient.

[0044] The topologies shown in the embodiments serve to utilize the existing galvanically isolating transducers as efficiently as possible by only passing the necessary electrical power through the galvanically isolating transducers.

[0045] The embodiment shown in Fig. 2 provides a further AC voltage connection 17 if the power supplied via the first AC voltage connection 16 is insufficient. Depending on the operating conditions, it may be advantageous to feed the power directly into the electrical energy storage device 5 or into the DC link 2 without having to route this power through a DC / DC converter.

[0046] The embodiment shown in Fig. 3 makes it possible to use the second DC / DC converter 10 even when only a single AC power supply is available. The second DC / DC converter 10 then supports the first DC / DC converter 6.

[0047] The embodiment shown in Fig. 4 enables, in one operating mode, the electrical power transferable between electrical energy storage 5 and inverter 7 not to be limited by the first DC / DC converter 6.

Claims

Patent claims 1. Device (100) for conveying thick material, comprising: an electric motor (1), a DC link (2), a first AC connection (16) which can be coupled to a first AC network (4), a first rectifier (3) which rectifies voltages present at the first AC connection (16), an electrical energy storage device (5), a first galvanically isolated DC / DC converter (6) which can be switched between the DC link (2) and the electrical energy storage device (5) depending on the operating mode and which is designed to transfer electrical power from the electrical energy storage device (5) to the DC link (2) and / or to transfer electrical power from the DC link (2) to the electrical energy storage device (5), and an inverter (7) supplied from the DC link (2) which is designed to control the electric motor (1),wherein the electrical power transferable via the inverter (7) towards the electric motor (1) is greater than the electrical power transferable via the galvanically isolated DC / DC converter (6) between the DC link (2) and the electrical energy storage device (5).

2. Device (100) for conveying thick material according to claim 1, characterized in that the device (100) for conveying thick material further comprises: a second AC voltage connection (17) which can be coupled to the first AC voltage network (4) or a second AC voltage network (9).

3. Device (100) for conveying thick material according to claim 2, characterized in that the device (100) for conveying thick material is designed to transmit electrical power from the second AC voltage connection (17) depending on the operating mode, in particular directly, either in the direction of the electrical energy storage device (5) or in the direction of the DC voltage intermediate circuit (2).

4. Device (100) for conveying thick material according to one of the preceding claims, characterized in that the device (100) for conveying thick material is designed to transfer electrical power depending on the operating mode either from the second AC voltage connection (17) to the DC intermediate circuit (2) or to the electrical energy storage device (5) or to transfer between the DC intermediate circuit (2) and the electrical energy storage device (5).

5. Device (100) for conveying thick material according to one of the preceding claims, characterized in that the device (100) for conveying thick material is designed to electrically connect the electrical energy storage device (5) to the DC intermediate circuit (2) depending on the operating mode without the intermediate of the first galvanically isolating DC / DC converter (6), in particular directly.

6. Device (100) for conveying thick material according to claim 5, characterized in that the device (100) for conveying thick material is designed to supply, depending on the operating mode, either the DC intermediate circuit (2) from the rectified voltage of the first rectifier (3), or the first galvanically isolating DC / DC converter (6) from the rectified voltage of the first rectifier (3).

7. Device (100) for conveying thick material according to one of claims 2 to 6, characterized in that the device (100) for conveying thick material further comprises: a second rectifier (8) which rectifies voltages present at the second AC voltage connection (17), and a second galvanically isolated DC / DC converter (10) with a first connection (10a) and a second connection (10b) which can be supplied from the rectified voltage of the second rectifier (8).

8. Device (100) for conveying thick material according to one of claims 2 to 7, characterized in that the device (100) for conveying thick material further comprises: a first controllable switching device (11) which, depending on its switching position, electrically connects the second terminal (10b) of the second DC / DC converter (10) either to the DC intermediate circuit (2) or to the electrical energy storage device (5).

9. Device (100) for conveying thick material according to one of claims 2 to 8, characterized in that the device (100) for conveying thick material further comprises: a second controllable switching means (12) which, depending on its switching position, electrically connects the first terminal (10a) of the second DC / DC converter (10) either to the second rectifier (8) or to the electrical energy storage device (5).

10. Device (100) for conveying thick material according to one of the preceding claims, characterized in that the device (100) for conveying thick material has a first operating mode during which electrical power from the first AC voltage network (4) and the electrical energy storage device (5) is transferred towards the electric motor (1), a second operating mode during which electrical power from the first AC voltage network (4) is transferred towards the electrical energy storage device (5) and towards the electric motor (1), and a third operating mode during which electrical power from the first AC voltage network (4) is transferred exclusively towards the electrical energy storage device (5).

11. Device (100) for conveying thick material according to one of the preceding claims, characterized in that the device (100) for conveying thick material has a number of hydraulic pumps (14) which are driven by the electric motor (1).

12. Device (100) for conveying thick material according to claim 11, characterized in that the device (100) for conveying thick material has a number of hydraulic cylinders (15) which are supplied by means of one or more of the number of hydraulic pumps (14).

13. Device (100) for conveying thick material according to claim 2, characterized in that the device (100) for conveying thick material further comprises: a second rectifier (8) which rectifies the voltages present at the second AC voltage terminal (17), a second galvanically isolated DC / DC converter (10) with a first terminal (10a) and a second terminal (10b), a first controllable switching element (11), a second controllable switching element (12), a third controllable switching element (13), wherein the first controllable switching element (11) connects the DC intermediate circuit (2) electrically either to the second terminal (10b) of the second galvanically isolated DC / DC converter (10) or to a first terminal (6a) of the first galvanically isolated DC / DC converter (6),wherein the second controllable switching device (12) electrically connects the first terminal (10a) of the second DC / DC converter (10) either to the first terminal (6a) of the first galvanically isolated DC / DC converter (6) or to the second rectifier (8), depending on its switching position, and wherein the third controllable switching device (13) electrically connects the first rectifier (3) either to the DC link (2) or to the first terminal (6a) of the first galvanically isolated DC / DC converter (6), 14. Device (100) for conveying thick material according to one of the preceding claims, characterized in that the inverter (7) is a 4-quadrant inverter.

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