Auto-polarity in an inductor based converter

Patent metadata

Field	Value
Publication number	US-9972761-B2
Application number	US-201514672684-A
Country	US
Kind code	B2
Filing date	Mar 30, 2015
Priority date	Mar 25, 2015
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

A thermoelectric energy harvesting system for charging an energy store from ambient thermal energy includes a thermoelectric energy generator (TEG), an automatic polarity monitor, and switching matrix. The polarity monitor detects when the polarity of an input voltage in the system is reversed relative to a standard voltage polarity, and causes the switching matrix to switch the inputs from the thermoelectric energy harvester.

First claim

What is claimed is:

1. A thermoelectric generator comprising:
a thermoelectric energy harvester;
a switch matrix;
a storage module; and
a polarity monitor, wherein:
the thermoelectric harvester has a first output and a second output having a voltage difference;
the switch matrix is connected to the thermoelectric harvester and comprises a circuit that connects one of the first and second outputs to an input voltage node at the storage module;
the storage module is connected to the switch matrix and comprises a converter for receiving the input voltage from the switch matrix and creating an amplified voltage from the input voltage; and
the polarity monitor is connected to the storage module and to the switch matrix, and comprises:
a polarity detection circuit for detecting a polarity of the amplified voltage; and
a control circuit operable to, in response to detecting a reversed polarity, cause the switch matrix to switch which of the first and second outputs is connected to the input voltage node.

2. The thermoelectric generator of claim 1 , wherein the switch matrix further comprises a first input, a second input, an output, and a ground; and wherein
each of the first and second inputs is connected to the first output with respective intervening first and second switches;
each of the first and second inputs is further connected with a ground by way of respective intervening third and fourth switches;
the first and fourth switches are connected with a first control circuit;
the second and third switches are connected with a second control circuit; and
the first and second control circuits are configured to be exclusively on/off or off/on such that, when the first control circuit is on, the first and fourth switches are open while the second and third switches are closed, connecting the first input to the output and the second input to ground; and when the first control circuit is off, the second and third switches are open and the first and fourth switches are closed, such that the second input is connected to the output and the first input is connected to ground.

3. The thermoelectric generator of claim 2 , wherein the control circuit further comprises a control output and an inverter connected to the control output that generates an inverted control output, and wherein the control output and the inverted control output are connected, respectively, with the second and first control circuits of the switch matrix.

4. The thermoelectric generator of claim 1 , wherein the polarity monitor further comprises a clocked comparator.

5. The thermoelectric generator of claim 1 , wherein,
the storage module further comprises a clocked, inductor-based boost converter that includes an inductor and a switching circuit, the switching circuit being operable to cause a charge-discharge sequence in the inductor for periodically generating an amplified voltage for charging and energy store, according to a clock-activated cycle.

6. The thermoelectric generator of claim 5 , wherein the polarity monitor is configured to measure the polarity of the amplified voltage during a discharge sequence in the clock-activated cycle.

7. The thermoelectric generator of claim 5 , wherein the polarity monitor further comprises a clocked comparator and a delay circuit connecting the clocked comparator to the storage module, such that the polarity monitor performs a comparison at a delay according to the clock-activated cycle.

8. The thermoelectric generator of claim 5 , wherein the polarity monitor is configured to measure the polarity of the amplified voltage according to an evaluation cycle, the evaluation cycle being longer than the clock-activated cycle.

9. The thermoelectric generator of claim 8 , further comprising an evaluation cycle control circuit operable to close a switch between the amplified voltage and the energy store during the evaluation cycle.

10. The thermoelectric generator of claim 1 , wherein each of the switch matrix, storage module, and polarity monitor are digital.

11. The thermoelectric generator of claim 1 , wherein each of the switch matrix, storage module, and polarity monitor are integrated on one or more chips.

Assignees

• Khalifa Univ Of Science Technology & Research
• Univ Khalifa Science & Technology

Inventors

• Alhawari Mohammad Radwan
• Mohammad Baker
• Saleh Hani Hasan Mustafa
• Elnaggar Mohammed Ismail

Classifications

• H02J2207/20

  Charging or discharging characterised by the power electronics converter · CPC title

• H02J7/34

  Parallel operation in networks using both storage and other DC sources, e.g. providing buffering (H02J7/14 takes precedence) · CPC title

• Y10T307/839

  Cross-Sectional Technologies · mapped topic

• H02J50/00

  Circuit arrangements or systems for wireless supply or distribution of electric power · CPC title

• H01L35/28 Primary

  Electricity · mapped topic