Voltage converter, electric drive system and method for reducing interference voltages
The present invention relates to interference suppression of interference signals from an inverter. To this end, a current-compensated inductor is provided at the input end of an inverter, in particular a pulse-controlled inverter. This current-compensated inductor is preferably arranged between a DC voltage source and an intermediate circuit capacitor of the inverter. Polyphase inductors at the AC voltage output of the inverter can be dispensed with in this way.
1. A voltage converter ( 1 ), comprising:
an inverter ( 10 ), comprising a two phase DC voltage input ( 110 ) that includes a first terminal ( 111 ) and a second terminal ( 112 ), which are configured to be connected to a DC voltage source ( 2 ) having a first terminal ( 21 ) and a second terminal ( 22 ), and the inverter ( 10 ) including a polyphase AC voltage output ( 120 ), which is connectable to an electrical load ( 3 );
a current-compensated inductor ( 11 ) including a first winding ( 11 a ) and a second winding ( 11 b ), wherein the first winding ( 11 a ) is arranged between the first terminal ( 111 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the first terminal ( 21 ) of the DC voltage source ( 2 ), and the second winding ( 11 b ) is arranged between the second terminal ( 112 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the second terminal ( 22 ) of the DC voltage source ( 2 ); and
a link capacitor ( 12 ) having one end connected between the first terminal ( 111 ) and the first winding ( 11 a ) of the current-compensated inductor ( 11 ) and the link capacitor ( 12 ) having another end connected between the second terminal ( 112 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the second winding ( 11 b ) of the current-compensated inductor ( 11 ).
2. The voltage converter ( 1 ) as claimed in claim 1 , wherein the AC voltage output ( 120 ) of the inverter ( 10 ) comprises a plurality of phase terminals ( 121 , 122 , 123 ), and wherein a capacitor ( 14 - i ) is arranged between each phase terminal ( 121 , 122 , 123 ) of the inverter ( 10 ) and a reference potential.
3. The voltage converter ( 1 ) as claimed in claim 2 , wherein the capacitor ( 14 - i ) or respectively a series circuit comprising the capacitor ( 14 - i ) and an electrical resistor ( 15 - i ) is arranged on a terminal element of the electrical load ( 3 ).
4. The voltage converter ( 1 ) as claimed in claim 1 , wherein the AC voltage output ( 120 ) of the inverter ( 10 ) comprises a plurality of phase terminals ( 121 , 122 , 123 ), and wherein a series circuit comprising a capacitor ( 14 - i ) and an electrical resistor ( 15 - i ) is arranged between each phase terminal ( 121 , 122 , 123 ) of the inverter ( 10 ) and a reference potential.
5. The voltage converter ( 1 ) as claimed in claim 1 , wherein the inverter ( 10 ) is a pulse-controlled inverter.
6. The voltage converter ( 1 ) as claimed in claim 1 , wherein the first winding ( 11 a ) is in direct connection to the first terminal ( 21 ) of the DC voltage source ( 2 ) and the second winding ( 11 b ) is in direct connection to the second terminal ( 22 ) of the DC voltage source ( 2 ).
7. An electric drive system, comprising:
a DC voltage source ( 2 ) including a first terminal ( 21 ) and a second terminal ( 22 );
an electric motor; and
a voltage converter ( 1 ) including
an inverter ( 10 ), including a two phase DC voltage input ( 110 ) having a first terminal ( 111 ) and a second terminal ( 112 ), which are connectable to the first terminal ( 21 ) and the second terminal ( 22 ) of the DC voltage source ( 2 ), and the inverter ( 10 ) including a polyphase AC voltage output ( 120 ), which is connectable to an electrical load ( 3 );
a current-compensated inductor ( 11 ) including a first winding ( 11 a ) and a second winding ( 11 b ), wherein the first winding ( 11 a ) is arranged between the first terminal ( 111 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the first terminal ( 21 ) of the DC voltage source ( 2 ), and wherein the second winding ( 11 b ) is arranged between the second terminal ( 112 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the second terminal ( 22 ) of the DC voltage source ( 2 ); and
a link capacitor ( 12 ) having one end connected between the first terminal ( 111 ) and the first winding ( 11 a ) of the current-compensated inductor ( 11 ) and the link capacitor ( 12 ) having another end connected between the second terminal ( 112 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the second winding ( 11 b ) of the current-compensated inductor ( 11 ).
8. The electric drive system as claimed in claim 7 , wherein the inverter ( 10 ) is a pulse-controlled inverter.
9. The electric drive system as claimed in claim 8 , wherein the AC voltage output ( 120 ) of the inverter ( 10 ) of the voltage converter ( 1 ) includes a plurality of phase terminals ( 121 , 122 , 123 ), and wherein a series circuit including a capacitor ( 14 - i ) and an electrical resistor ( 15 - i ) is arranged between each phase terminal ( 121 , 122 , 123 ) of the inverter ( 10 ) and a reference potential.
10. The electric drive system as claimed in claim 7 , wherein the AC voltage output ( 120 ) of the inverter ( 10 ) includes a plurality of phase terminals ( 121 , 122 , 123 ), and wherein a series circuit comprising a capacitor ( 14 - i ) and an electrical resistor ( 15 - i ) is arranged between each phase terminal ( 121 , 122 , 123 ) of the inverter ( 10 ) and a reference potential.
11. The electric drive system as claimed in claim 7 , wherein the AC voltage output ( 120 ) of the inverter ( 10 ) of the voltage converter ( 1 ) includes a plurality of phase terminals ( 121 , 122 , 123 ), and wherein a capacitor ( 14 - i ) is arranged between each phase terminal ( 121 , 122 , 123 ) of the inverter ( 10 ) and a reference potential.
12. The electric drive system as claimed in claim 11 , wherein the capacitor ( 14 - i ) or respectively a series circuit including the capacitor ( 14 - i ) and an electrical resistor ( 15 - i ) is arranged on a terminal element of the electrical load ( 3 ).
13. The electric drive system as claimed in claim 7 , wherein the first winding ( 11 a ) is in direct connection to the first terminal ( 21 ) of the DC voltage source ( 2 ) and the second winding ( 11 b ) is in direct connection to the second terminal ( 22 ) of the DC voltage source ( 2 ).
14. A method for reducing interference voltages of a voltage converter, comprising the following steps:
providing a DC voltage source ( 2 ) having a first terminal ( 21 ) and a second terminal ( 22 ); and
the voltage converter ( 1 ) including:
an inverter ( 10 ) including a two phase DC voltage input ( 110 ) having a first terminal ( 111 ) and a second terminal ( 112 ), and a polyphase AC voltage output ( 120 );
a current-compensated inductor ( 11 ) coupled between the DC voltage source ( 2 ) and the DC voltage input ( 110 ) of the inverter ( 10 ) so that a first winding ( 11 a ) of the current-compensated inductor ( 11 ) is arranged between the first terminal ( 111 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the first terminal ( 21 ) of the DC voltage source ( 2 ) and a second winding ( 11 b ) of the current-compensated inductor ( 11 ) is arranged between the second terminal ( 112 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the second terminal ( 22 ) of the DC voltage source ( 2 ); and
a link capacitor ( 12 ) having one end connected between the first terminal ( 111 ) and the first winding ( 11 a ) of the current-compensated inductor ( 11 ) and the link capacitor ( 12 ) having another end connected between the second terminal ( 112 ) of the DC voltage input ( 110 ) of the inverter ( 10 ) and the second winding ( 11 b ) of the current-compensated inductor ( 11 ).
15. The method as claimed in claim 14 , furthermore including a step for arranging respectively a capacitor ( 14 - i ) or a series circuit including a capacitor ( 14 - i ) and an electrical resistor ( 15 - i ) between a reference potential and each phase of the polyphase AC voltage output ( 120 ) of the inverter ( 10 ).
16. The method as claimed in claim 14 , wherein the inverter ( 10 ) is a pulse-controlled inverter.
17. The method as claimed in claim 14 , wherein the first winding ( 11 a ) is in direct connection to the first terminal ( 21 ) of the DC voltage source ( 2 ) and the second winding ( 11 b ) is in direct connection to the second terminal ( 22 ) of the DC voltage source ( 2 ).