CIRCUIT ARRANGEMENT FOR IDENTIFYING NETWORK ZERO CROSSINGS

• US 20100109709A1
• Filed: 01/22/2008
• Published: 05/06/2010
• Est. Priority Date: 03/28/2007
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Hallak, Jalal
• Granted Patent: US 8,115,517 B2
• Time in Patent Office: Days
• US Class Current: 327/79
• CPC Class Codes: H02M 1/083 for the ignition at the zero crossing of the voltage or the current

Abstract

A circuit arrangement for identifying network zero crossings of a network voltage of an alternating current network is provided. A measurement current generated by the network voltage is supplied to a zero crossing detector in order to produce a network zero crossing signal. A current sink is arranged between a live conductor and a neutral conductor of the alternating current network, the current sink allowing the path of a current value of the measurement current generated by the network voltage to be defined.

Claims

1-8. -8. (canceled)

9. A circuit arrangement for detection of zero crossings of a network voltage of an alternating current network, comprising:

a zero crossing detector, a measurement current generated by the network voltage being supplied to the zero crossing detector to form a zero crossing signal,

a variable current sink arranged between live conductor and neutral conductor of the alternating current network,

wherein a curve of a current value of the measurement current generated by the network voltage is defined by the variable current sink, and

wherein the curve of the current value of the measurement current caused by the variable current sink is directly proportional to a curve of the network voltage.

10. The circuit arrangement as claimed in claim 9, wherein the curve of the current value caused by the variable current sink is limited by a minimum value.

11. The circuit arrangement as claimed in claim 9, wherein the variable current sink is arranged in series with a resistor and the zero crossing detector is a comparator which is arranged in parallel to the resistor.

12. The circuit arrangement as claimed in claim 9, wherein the variable current sink is arranged in series with a resistor and the zero crossing detector is a operational amplifier which is arranged in parallel to the resistor.

13. The circuit arrangement as claimed in claim 11, wherein an output of the comparator is connected to an element for electrical isolation.

14. The circuit arrangement as claimed in claim 12, wherein an output of the operational amplifier is connected to an element for electrical isolation.

15. The circuit arrangement as claimed in claim 9, wherein the variable current sink is arranged in series with an element for electrical isolation.

16. The circuit arrangement as claimed in claim 13, wherein the element for electrical isolation is an optocoupler.

17. The circuit arrangement as claimed in claim 14, wherein the element for electrical isolation is an optocoupler.

18. The circuit arrangement as claimed in claim 15, wherein the element for electrical isolation is an optocoupler.

19. The circuit arrangement as claimed in claim 9, wherein the variable current sink is a unidirectional current sink.

20. The circuit arrangement as claimed in claim 9, wherein the variable current sink is a bidirectional current sink.

21. An inverter for feeding electrical energy into an alternating current network, comprising:

a circuit arrangement for detection of zero crossings of a network voltage of an alternating current network, the circuit arrangement comprising;

a zero crossing detector, a measurement current generated by the network voltage being supplied to the zero crossing detector to form a zero crossing signal,

a variable current sink arranged between live conductor and neutral conductor of the alternating current network,

wherein a curve of a current value of the measurement current generated by the network voltage is defined by the variable current sink, and

wherein the curve of the current value of the measurement current caused by the variable current sink is directly proportional to a curve of the network voltage.

22. The inverter as claimed in claim 21, wherein the curve of the current value caused by the variable current sink is limited by a minimum value.

23. The inverter as claimed in claim 21, wherein the variable current sink is arranged in series with a resistor and the zero crossing detector is a comparator which is arranged in parallel to the resistor.

24. The inverter as claimed in claim 21, wherein the variable current sink is arranged in series with a resistor and the zero crossing detector is an operational amplifier which is arranged in parallel to the resistor.

25. The inverter as claimed in claim 23, wherein an output of the comparator is connected to an element for electrical isolation and the element for electrical isolation is an optocoupler.

26. The circuit arrangement as claimed in claim 24, wherein an output of the operational amplifier is connected to an element for electrical isolation and the element for electrical isolation is an optocoupler.

27. The inverter as claimed in claim 21, wherein the variable current sink is arranged in series with an element for electrical isolation and the element for electrical isolation is an optocoupler.

28. The inverter as claimed in claim 21, wherein the variable current sink is a unidirectional or bidirectional current sink.