Converter, electrical polyphase system and method

• US 10,454,331 B2
• Filed: 12/05/2016
• Issued: 10/22/2019
• Est. Priority Date: 12/07/2015
• Status: Active Grant

• Current Assignee: Dr Ing hc F Porsche AG (Volkswagen AG)
• Original Assignee: Dr Ing hc F Porsche AG (Volkswagen AG)
• Inventors: Gotz, Stefan
• Primary Examiner(s): Islam, Muhammad S
• Application Number:
  US15/368,788
• Publication Number:
  US 20170163115A1
• Time in Patent Office: 1,051 Days
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 17/12 for multi-phase current
• CPC Class Codes: H02K 2213/12 Machines characterised by the modularity of some components
• CPC Class Codes: H02K 3/28 Layout of windings or of connections between windings windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32
• CPC Class Codes: H02M 7/4835 comprising two or more cells, each including a switchable capacitor, the capacitors having a nominal charge voltage which corresponds to a given fraction of the input voltage, and the capacitors being selectively connected in series to determine the instantaneous output voltage
• CPC Class Codes: H02M 7/49 Combination of the output voltage waveforms of a plurality of converters
• CPC Class Codes: H02P 25/22 Multiple windings; Windings for more than three phases
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: H02P 27/14 with three or more levels of voltage

Abstract

An electric machine has a multiplicity of windings having a first terminal and a second terminal. At least one node exists to which one of the two terminals of a respective winding from the multiplicity of windings is electrically connected. The corresponding other terminal of a respective winding from the multiplicity of windings is electrically connected to a phase terminal, and to a modular multilevel converter that has a multiplicity of individual modules that are connected up in series to form a ring. At least one tap can be arranged between two respective adjacent individual modules and provides a phase terminal to which the first or the second terminal of a winding from the multiplicity of windings of the electric machine is electrically connected. A number of taps of the modular multilevel converter corresponds exactly to a number of windings from the multiplicity of windings of the electric machine.

Claims

1. A modular multilevel converter comprising:

at least one control unit;

a plurality of individual modules that each have a plurality of switching elements controlled by the at least one control unit and at least one electrical energy store, wherein the plurality of individual modules are connected together in succession to form a closed ring, each of the plurality of individual modules configurable by the at least one control unit between at least a bypass connection and a series connection with an adjacent module by the plurality of switching elements allowing energy stores of adjacent individual modules to be selectively connected together; and

at least four phase terminals on the dosed ring, each phase terminal connected between respective adjacent individual modules of the dosed ring and separated from an adjacent phase terminal by at least two individual modules of the closed ring, wherein a voltage difference between two adjacent phase terminals of the closed ring is regulated by the at least one control unit configuring the plurality of individual modules.

2. The modular multilevel converter as claimed in claim 1, in which each of at least four taps are arranged between two respective adjacent individual modules to provide the at least four phase terminals.

3. The modular multilevel converter as claimed in claim 1, in which the modular multilevel converter has a phase module comprising at least two individual modules that branches off from the ring and that has one end connected to a tap and has the other end connected to a reference potential.

4. The modular multilevel converter as claimed in claim 1, in which at least one tap is connected to a reference potential via an electrical connection that has at least one electrical resistance, an inductance or both at least one electrical resistance and an inductance.

5. The modular multilevel converter as claimed in claim 1, in which the switching elements of the multiplicity of individual modules are low-voltage semiconductor switching elements.

6. An electrical polyphase system comprising:

an electric machine that has a multiplicity of windings having a first terminal and a second terminal,

at least one node to which either the first or the second terminal of a respective winding from the multiplicity of windings is electrically connected, and the corresponding other terminal of the first and second terminals of a respective winding from the multiplicity of windings is electrically connected to a phase terminal, and

the modular multilevel converter of claim 1, wherein at least one tap is arranged between two respective adjacent individual modules of the plurality of modules and provides a phase terminal to which the first or the second terminal of a winding from the multiplicity of windings of the electric machine is electrically connected,

wherein a number of taps of the modular multilevel converter corresponds exactly to a number of windings from the multiplicity of windings of the electric machine.

7. The electrical polyphase system as claimed in claim 6, in which the electric machine operates as a generator or as a motor.

8. The converter of claim 1, wherein the individual modules are additionally configurable by the control unit in at least one of a disconnection or a parallel connection with the adjacent module by the plurality of switching elements.

9. The modular multilevel converter as claimed in claim 2, in which each of the individual modules have a first side and a second side, the first side having two terminals and the second side having two terminals.

10. The modular multilevel converter as claimed in claim 9, in which the individual modules are each electrically connected to one another by two electrical conductors.

11. The modular multilevel converter as claimed in claim 10, in which the tap for providing a phase terminal is arranged on one of the two electrical conductors.

12. The modular multilevel converter as claimed in claim 10, in which the tap for providing a phase terminal is arranged on both electrical conductors.