Switching circuits for extracting power from an electric power source and associated methods

• US 9,698,599 B2
• Filed: 04/11/2016
• Issued: 07/04/2017
• Est. Priority Date: 08/18/2010
• Status: Active Grant

• Current Assignee: Volterra Semiconductor LLC (Analog Devices, Inc.)
• Original Assignee: Volterra Semiconductor LLC (Analog Devices, Inc.)
• Inventors: Jergovic, Ilija, Lidsky, David B., Stratakos, Anthony J., McJimsey, Michael D., Ikriannikov, Alexandr, Yao, Kaiwei, Der Minassians, Artin, Zuniga, Marco A., Borisavljevic, Ana
• Primary Examiner(s): DEBERADINIS, ROBERT L
• Application Number:
  US15/095,495
• Publication Number:
  US 20160226247A1
• Time in Patent Office: 449 Days
• Field of Search: 307 18
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 1/106 for load balancing, symmetrisation, or sharing
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H03K 17/102 in field-effect transistor switches
• CPC Class Codes: H03K 17/122 in field-effect transistor switches
• CPC Class Codes: H03K 17/145 in field-effect transistor switches
• CPC Class Codes: H03K 17/693 Switching arrangements with several input- or output-terminals, e.g. multiplexers, distributors logic circuits H03K19/00; code converters H03M5/00, H03M7/00
• CPC Class Codes: H03K 2217/0036 Means reducing energy consumption
• CPC Class Codes: H03K 2217/0054 Gating switches, e.g. pass gates
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers

Abstract

An electric power system includes N electric power sources and N switching circuits, where N is an integer greater than one. Each switching circuit includes an input port electrically coupled to a respective one of the N electric power sources, an output port, and a first switching device adapted to switch between its conductive and non-conductive states to transfer power from the input port to the output port. The output ports of the N switching circuits are electrically coupled in series and to a load to establish an output circuit. Each of the N switching circuits uses an interconnection inductance of the output circuit as a primary energy storage inductance of the switching circuit.

Claims

1. An electric power system, comprising:

a photovoltaic panel including R rows and C columns of photovoltaic cells divided into N photovoltaic sub-modules, each of N, R, and C being a respective integer greater than one; and

N buck converters, each buck converter including;

an input port electrically coupled to a respective one of the N photovoltaic sub-modules, and

an output port;

the output ports of the N buck converters being electrically coupled in series;

each of the N buck converters configured to at least substantially maximize an amount of electric power extracted from the respective one of the N photovoltaic sub-modules electrically coupled to the input port of the buck converter.

2. The electric power system of claim 1, each of the N photovoltaic sub-modules including R of the photovoltaic cells electrically coupled in series.

3. The electric power system of claim 1, each of the N photovoltaic sub-modules including X of the photovoltaic cells electrically coupled in series, X being equal to the product of two and R.

4. The electric power system of claim 1, each of the N photovoltaic sub-modules including C of the photovoltaic cells electrically coupled in series.

5. The electric power system of claim 1, each of the N photovoltaic sub-modules including X of the photovoltaic cells electrically coupled in series, X being equal to the product of two and C.

6. The electric power system of claim 1, each of the N buck converters including:

a first switching device electrically coupled between a switching node and a first terminal of the input port;

a second switching device electrically coupled between the switching node and a second terminal of the input port;

an inductor electrically coupled between the switching node and a first terminal of the output port; and

a capacitor electrically coupled between the first terminal of the output port and a second terminal of the output port;

the second terminal of the input port and the second terminal of the output port each being electrically coupled to a common first node.

7. The electric power system of claim 6, in each of the N buck converters, the common first node being a positive input node.

8. The electric power system of claim 6, in each of the N buck converters, the common first node being a negative input node.

9. An electric power system, comprising:

N photovoltaic devices, N being an integer greater than one; and

N buck converters, each buck converter including;

an input port electrically coupled to a respective one of the N photovoltaic devices,

an output port,

a first switching device electrically coupled between a switching node and a first terminal of the input port,

a second switching device electrically coupled between the switching node and a second terminal of the input port,

an inductor electrically coupled between the switching node and a first terminal of the output port,

a capacitor electrically coupled between the first terminal of the output port and a second terminal of the output port, and

a controller configured to;

(a) control switching of the first and second switching devices to at least substantially maximize an amount of electric power extracted from the respective one of the N photovoltaic devices electrically coupled to the input port, in a first operating mode, (b) detect a voltage across the input port falling below a threshold value, (c) switch the buck converter from its first operating mode to a second operating mode, in response to detecting the voltage across the input port falling below the threshold value, and (d) control the second switching device to continuously operate in its conductive state, in the second operating mode;

the output ports of the N buck converters being electrically coupled in series.

10. The electric power system of claim 9, in each of the N buck converters, the second terminal of the input port and the second terminal of the output port being electrically coupled to a common positive input node.

11. The electric power system of claim 9, in each of the N buck converters, the second terminal of the input port and the second terminal of the output port being electrically coupled to a common negative input node.

12. A method for extracting power from photovoltaic devices, comprising:

for each of a plurality of buck converters, causing first and second switching devices of the buck converter to switch between their conductive and non-conductive states to at least substantially maximize an amount of electric power extracted from a respective photovoltaic device electrically coupled to a respective input port of the buck converter;

powering a load at least partially from energy available at output ports of the plurality of buck converters, the output ports being electrically coupled in series;

detecting a voltage across the input port of one of the plurality of buck converters falling below a threshold value; and

in response to the detecting the voltage across the input port of the one of the plurality of buck converters falling below the threshold value, causing;

(a) the first switching device of the one of the plurality of buck converters to continuously operate in its non-conductive state and (b) the second switching device of the one of the plurality of buck converters to continuously operate in its conductive state.