Electric drive system

Patent metadata

Field	Value
Publication number	US-9899948-B2
Application number	US-201515119760-A
Country	US
Kind code	B2
Filing date	Jan 8, 2015
Priority date	Feb 27, 2014
Publication date	Feb 20, 2018
Grant date	Feb 20, 2018

Abstract

The invention relates to an electric drive system with an n-phase electric machine, n>1, having at least two multiphase winding strands; a first inverter, the output connections of which are connected to the phase connections of a first of the multiphase winding strands of the electric machine; a second inverter, which is connected in parallel to the first inverter and the output connections of which are connected to the phase connections of a second of the multiphase winding strands of the electric machine; and a DC voltage source, which has a plurality of battery modules connected in series and a first output connection of which is connected to a first input connection of the first inverter and second output connection of which is connected to a first input connection of the second inverter. A second input connection of the first inverter and a second input connection of the second inverter are connected to each other such that the first inverter and the second inverter are arranged in a series circuit, and the second input connection of the first inverter and the second input connection of the second inverter are connected to a center tap of the DC voltage source between two sub-groups of the battery modules connected in series.

First claim

The invention claimed is:

1. An electric drive system ( 30 ), comprising:
an n-phase electric machine ( 6 ), n>1, having at least two multiphase winding strands ( 6 a , 6 b );
a first inverter ( 3 a ), output connections of which are connected to the phase connections of a first of the multiphase winding strands ( 6 a , 6 b ) of the electric machine ( 6 );
a second inverter ( 3 b ), the output connections of which are connected to the phase connections of a second of the multiphase winding strands ( 6 a , 6 b ) of the electric machine ( 6 );
a DC voltage source ( 1 ), which has a plurality of battery modules ( 5 ) connected in series and a first output connection of which is connected to a first input connection of the first inverter ( 3 a ) and a second output connection of which is connected to the first input connection of the second inverter ( 3 b ); and
a first DC voltage intermediate circuit ( 2 a ) connected to the first input connection of the first inverter ( 3 a ) and to a second input connection of the first inverter ( 3 a ),
wherein the second input connection of the first inverter ( 3 a ) and a second input connection of the second inverter ( 3 b ) are connected to each other such that the first inverter ( 3 a ) and the second inverter ( 3 b ) are arranged in a series circuit, and
wherein the second input connection of the first inverter ( 3 a ) and the second input connection of the second inverter ( 3 b ) are connected to a center tap (M) of the DC voltage source ( 1 ) between two sub-groups of the battery modules ( 5 ) connected in series.

2. The electric drive system ( 30 ) according to claim 1 , wherein the first and the second inverter ( 3 a , 3 b ) each comprise a three-phase, self-piloted inverter, which includes three symmetrical half bridges each including two power semiconductor switches (H 1 , H 2 ; H 3 , H 4 ; H 5 , H 6 ) in a series circuit.

3. The electric drive system ( 30 ) according to claim 2 , wherein the power semiconductor switches (H 1 , H 2 ; H 3 , H 4 ; H 5 , H 6 ) are MOSFET switches or IGBT switches.

4. The electric drive system ( 30 ) according to claim 2 , further comprising:
a control device configured to actuate the power semiconductor switches (H 1 , H 2 ; H 3 , H 4 ; H 5 , H 6 ) of the first inverter ( 3 a ) and the second inverter ( 3 b ),
wherein the control device is disposed on a central control circuit board for the first inverter ( 3 a ) and the second inverter ( 3 b ).

5. An electric drive system ( 30 ) comprising:
an n-phase electric machine ( 6 ), n>1, having at least two multiphase winding strands ( 6 a , 6 b );
a first inverter ( 3 a ), output connections of which are connected to the phase connections of a first of the multiphase winding strands ( 6 a , 6 b ) of the electric machine ( 6 );
a second inverter ( 3 b ), the output connections of which are connected to the phase connections of a second of the multiphase winding strands ( 6 a , 6 b ) of the electric machine ( 6 );
a DC voltage source ( 1 ), which has a plurality of battery modules ( 5 ) connected in series and a first output connection of which is connected to a first input connection of the first inverter ( 3 a ) and a second output connection of which is connected to the first input connection of the second inverter ( 3 b );
at least one third inverter ( 3 c ) connected in parallel to the first inverter ( 3 a ), input connections of which are each coupled to input connections of the first inverter ( 3 a ); and
at least one fourth inverter ( 3 d ) which is connected in parallel to the second inverter ( 3 b ) and the input connections of which are each coupled to input connections of the second inverter ( 3 b ),
wherein a second input connection of the first inverter ( 3 a ) and a second input connection of the second inverter ( 3 b ) are connected to each other such that the first inverter ( 3 a ) and the second inverter ( 3 b ) are arranged in a series circuit, and
wherein the second input connection of the first inverter ( 3 a ) and the second input connection of the second inverter ( 3 b ) are connected to a center tap (M) of the DC voltage source ( 1 ) between two sub-groups of the battery modules ( 5 ) connected in series.

6. The electric drive system ( 30 ) according to claim 5 , wherein the first inverter, the second inverter, the third inverter and the fourth inverter ( 3 a , 3 b ) each comprise a three-phase, self-piloted inverter, which includes three symmetrical half bridges each including two power semiconductor switches (H 1 , H 2 ; H 3 , H 4 ; H 5 , H 6 ) in a series circuit.

7. The electric drive system ( 30 ) according to claim 6 , wherein the power semiconductor switches (H 1 , H 2 ; H 3 , H 4 ; H 5 , H 6 ) are MOSFET switches or IGBT switches.

8. The electric drive system ( 30 ) according to claim 7 , further comprising:
a control device configured to actuate the power semiconductor switches (H 1 , H 2 ; H 3 , H 4 ; H 5 , H 6 ) of the first inverter ( 3 a ), the second inverter ( 3 b ), the third inverter ( 3 c ) and the fourth inverter ( 3 d ),
wherein the control device is disposed on a central control circuit board for the first inverter ( 3 a ), the second inverter ( 3 b ), the third inverter ( 3 c ) and the fourth inverter ( 3 d ).

9. The electric drive system ( 30 ) according to claim 8 , wherein the third invertor ( 3 c ) includes output connections connected to the phase connections of a third multiphase winding strand ( 6 c ) of the electric machine ( 6 ), wherein the fourth invertor ( 3 d ) includes output connections connected to the phase connections of a fourth multiphase winding strand ( 6 d ) of the electric machine ( 6 ), and wherein the n-phase electric machine ( 6 ) is a twelve-phase machine.

10. The electric drive system ( 30 ) according to claim 1 , further comprising a second DC voltage intermediate circuit ( 2 b ) connected to the first input connection of the second inverter ( 3 b ) and to the second input connection of the second inverter ( 3 b ).

11. An electric drive system ( 30 ) comprising:
an n-phase electric machine ( 6 ), n>1, having at least four multiphase winding strands ( 6 a , 6 b , 6 c , 6 d );
a first inverter ( 3 a ), output connections of which are connected to the phase connections of a first of the multiphase winding strands ( 6 a ) of the electric machine ( 6 );
a second inverter ( 3 b ), output connections of which are connected to the phase connections of a second of the multiphase winding strands ( 6 b ) of the electric machine ( 6 );
a third inverter ( 3 c ), output connections of which are connected to the phase connections of a third of the multiphase winding strands ( 6 c ) of the electric machine ( 6 );
a fourth inverter ( 3 d ), output connections of which are connected to the phase connections of a fourth of the multiphase winding strands ( 6 d ) of the electric machine ( 6 ); and
a DC voltage source ( 1 ), which has a plurality of battery modules ( 5 ) connected in series and a first output connection of which is connected to a first input connection of the first inverter ( 3 a ) and a first input connection of the third inverter ( 3 c ), and a second output connection of which is connected to the first input connection of the second inverter ( 3 b ) and a first input connection of the fourth inverter ( 3 d )
wherein the second input connection of the first inverter ( 3 a ) and the second input connection of the third inverter ( 3 c ) are connected to a first center tap (M) of the DC voltage source ( 1 ) between two

Assignees

• Bosch Gmbh Robert

Inventors

• Butzmann Stefan
• Braun Martin

Classifications

• B60L11/1864

  Operations & Transport · mapped topic

• B60L11/1803

  Operations & Transport · mapped topic

• H02M7/493

  the static converters being arranged for operation in parallel · CPC title

• Y02T10/641

  Cross-Sectional Technologies · mapped topic

• B60L2220/58

  with more than three phases · CPC title