Method and device for protecting several strings of a photovoltaic generator from reverse currents
AssigneeSMA Solar Technology AG
InventorsSven Bremicker, Adrian Haering, Matthias Walter, Henrik Wolf, Joachim Laschinski
Life of this patent
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Abstract
In order to protect reverse currents, several strings of a photovoltaic generator, which are connected in small groups respectively via a DC/DC-converter, parallel to a common DC voltage intermediate circuit, the current which flows over each of the DC/DC-converter is detected and if a reverse current is detected flowing through one of the DC/DC converters, the converter is stopped by controlling the DC/DC-converter.
Claims16
A method for reverse current protection of a number of strings of a photovoltaic generator being connected to a common DC link in parallel in small groups respectively via a corresponding DC/DC converter, comprising:
- detecting a current flowing via each of the DC/DC converters;
- and
- inhibiting a reverse current flowing through one of the DC/DC converters by a control of the DC/DC converter in response to the detection,
- wherein the reverse current flowing through one of the DC/DC converters is inhibited by a control of the remaining DC/DC converters not having a reverse current, thereby interrupting the flow of current from the strings connected thereby to the common DC link.
A device for reverse current protection of a number of strings of a photovoltaic generator being connected to a common DC link in parallel in small groups respectively via a corresponding DC/DC converter, comprising:
- a current sensor configured to detect a current flowing via a respective DC/DC converter;
- and
- a central control system configured to inhibit a flow of a reverse current through one of the DC/DC converters by the control of one of the DC/DC converters,
- wherein the central control system is configured to inhibit the reverse current flowing through the one of the DC/DC converters by a control of the remaining DC/DC converters not having the reverse current, thereby interrupting the flow of current from the strings connected thereby to the common DC link.
A method for reverse current protection of a number of strings of a photovoltaic generator being connected to a common DC link in parallel in small groups respectively via a corresponding DC/DC converter, comprising:
- detecting a current flowing via each of the DC/DC converters;
- and
- inhibiting a reverse current flowing through one of the DC/DC converters by a control of the DC/DC converter in response to the detection,
- wherein the DC/DC converters are configured as boost converters, and wherein the reverse current flowing through one of the DC/DC converters is inhibited by a continuous opening or closure of the boost converter switches on the remaining DC/DC converters not having a reverse current.
Dependencies are inferred from the claim text.