Thermoelectric power generating apparatus and method for driving same

• US 6,028,263 A
• Filed: 04/30/1998
• Issued: 02/22/2000
• Est. Priority Date: 05/14/1997
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Kushibiki, Keiko, Kobayashi, Masakazu, Furuya, Kenji, Shinohara, Kazuhiko
• Primary Examiner(s): Gorgos, Kathryn
• Assistant Examiner(s): Parsons, Thomas H
• Application Number:
  US09/069,981
• Time in Patent Office: 663 Days
• Field of Search: 136/200, 136/201, 136/203, 136/205
• US Class Current: 136/201
• CPC Class Codes: H10N 10/00 Thermoelectric devices comprising a junction of dissimilar materials, i.e. devices exhibiting Seebeck or Peltier effects integrated devices or assemblies of multiple devices H10N19/00
• CPC Class Codes: H10N 10/10 operating with only the Peltier or Seebeck effects

Abstract

An apparatus for generating a thermoelectric power and method for driving the same. The disclosed apparatus comprises: a plurality of power generation units, each power generator unit including at least one thermocouple and being capable of mutually generating an equal output voltage; a connection form switch for switching an electrical connection form of each one of the power generator units between a serial connection of the corresponding one of the power generator units to another of the remaining power generator units and a parallel connection thereof to another of the remaining power generator units; a parallel voltage detector for measuring a parallel voltage when the plurality of power generator units are connected in parallel to each other; a connection form detector for determining the connection form of all of the power generator units in one of three forms consisting of a serial connection, a parallel connection, and a combination of the serial and parallel connections, so as to generate a thermoelectric power according to a load connected to the thermoelectric power generating apparatus on the basis of a value of the parallel voltage measured by the parallel voltage measuring block; and a broken wire detector for detecting whether a wire breakage in each of the power generator units occurs.

Claims

1. A thermoelectric power generating apparatus, comprising:

a plurality of power generator units, each power generator unit including at least one thermocouple and being capable of mutually generating an equal output voltage;

a connection form switch for switching an electrical connection form of each one of the power generator units with respect to another of the power generator units between a serial connection and a parallel connection;

a parallel voltage detector for measuring a parallel voltage when the plurality of power generator units are connected in parallel to each other;

a connection form detector for determining the connection form of all of the power generator units, the connection form being one of three forms consisting of a serial connection, a parallel connection, and a combination of the serial and parallel connections, so as to generate a thermoelectric power according to a load connected to the thermoelectric power generating apparatus on the basis of a value of the parallel voltage measured by the parallel voltage detector; and

a broken wire detector for detecting an occurrence of a wire breakage in each of the power generator units.

2. A thermoelectric power generating apparatus as claimed in claim 1, wherein the plurality of power generator units includes a plurality of thermoelectric modules having one or more thermocouples or a plurality of thermoelectric module blocks, each thermoelectric module block having the plurality of the mutually connected thermoelectric modules.

3. A thermoelectric power generating apparatus as claimed in claim 2, wherein each one of the thermoelectric modules is connected in series with the other thermoelectric modules, is connected in parallel with the other thermoelectric modules, or is connected in a combination of serial and parallel connections with the other thermoelectric modules.

4. A thermoelectric power generating apparatus as claimed in claim 3, wherein the plurality of the power generator units include the plurality of thermoelectric module blocks which are juxtaposed on an outer peripheral surface of an exhaust tube of an automotive vehicular engine and enclosed with at least one heat radiating fin, each thermoelectric module block having ten serially connected thermoelectric modules of the same ratings along a direction of a heat flow of an exhaust gas in the exhaust tube, each thermoelectric module having eight n-type thermocouple elements and p-type thermocouple elements serially connected together by means of metal electrodes and grasped by means of an electrically insulative substrate.

5. A thermoelectric power generating apparatus as claimed in claim 3, wherein the plurality of the power generator units include the plurality of the thermoelectric module blocks which are disposed on an outer wall of an incinerator and enclosed with a heat radiating fin, each thermoelectric module block having the plurality of the thermoelectric module block having the plurality of the thermoelectric modules which are connected in series with one another in a horizontal direction of the outer wall of the incinerator and whose connection number is varied linearly in a vertical direction of the outer wall of the incinerator.

6. A thermoelectric power generating apparatus as claimed in claim 4, wherein the load is a vehicular battery.

7. A thermoelectric power generating apparatus as claimed in claim 6, wherein the first comparator compares the parallel voltage (Vp) with the voltage drop (Vfi) until an i-th number of the power generator units whose measured voltage drop (Vfi) to be compared with the measured parallel voltage has reached to the whole number (N) of the power generator units.

8. A thermoelectric power generating apparatus as claimed in claim 7, wherein when the first comparator determines that the value of the measured voltage drop (Vfi) is smaller than the parallel voltage (Vp) by a predetermined percentage, the broken wire detecting block detects that the wire breakage in any one of the power generator units with which the external electrical resistance is connected in series occurs and the connection form determining block determines the connection form of each of the remaining power generator units in the form of the serial connection.

9. A thermoelectric power generating apparatus as claimed in claim 8, wherein the predetermined percentage is about 50 percents.

10. A thermoelectric power generating apparatus as claimed in claim 8, which further comprises a thermoelectric power generation time detector for determining whether it is a time for the power generator units to start a thermoelectric power generation on the basis of the measured parallel voltage Vp.

11. A thermoelectric power generating apparatus as claimed in claim 10, wherein the thermoelectric power generation time detector block comprises a setter for setting a threshold voltage (Vps) required for each of the power generator units to generate the thermoelectric power and a second comparator for comparing the threshold voltage (VPs) with the measured parallel voltage (Vp) so as to determine whether the value of the measured parallel voltage (Vp) has reached to the set threshold voltage (Vps).

12. A thermoelectric power generating apparatus as claimed in claim 11, wherein Vps=Vp/n, wherein n denotes the number of the power generator units in which no wire breakage occurs.

13. A thermoelectric power generating apparatus as claimed in claim 12, wherein the connection form detector, the broken wire detector, and the power generation start time detector are integrally constituted by a microcomputer.

14. A thermoelectric power generating apparatus as claimed in claim 13, wherein the microcomputer includes a nonvolatile memory in which the number of any one of the power generator units in which the wire breakage occurs is stored.

15. A thermoelectric power generating apparatus as claimed in claim 1, wherein the broken wire detector includes:

an external resistance connected in series with each of the power generator units;

a voltage drop detector for measuring a voltage drop across the external resistance when the external resistance is connected in series with each of the power generator units; and

a first comparator for comparing a value of the measured voltage drop (Vfi) and the value of the parallel voltage so as to determine whether the value of the measured voltage drop is below the parallel voltage (Vp).

16. A thermoelectric power generating apparatus as claimed in claim 15, wherein the value of the external resistance falls in a range between 1 and 10,000 times as large as a resistance value of an internal resistance of each power generator unit.

17. A thermoelectric power generating apparatus as claimed in claim 16, wherein the value of the external resistance is 100 times as large as the internal resistance of each power generator unit.

18. A thermoelectric power generating apparatus, comprising:

a plurality of power generator units, each power generator unit including at least one thermocouple and being capable of mutually generating an equal output voltage;

connection form switching means for switching an electrical connection form of each one of the power generator units between a serial connection of the corresponding one of the power generator units to another of the remaining power generator units and a parallel connection thereof to another of the remaining power generator units;

parallel voltage measuring means for measuring a parallel voltage when the plurality of power generator units are connected in parallel to each other;

connection form determining means for determining the connection form of all of the power generator units in one of three forms consisting of a serial connection, a parallel connection, and a combination of the serial and parallel connections, so as to generate a thermoelectric power according to a load connected to the thermoelectric power generating apparatus on the basis of a value of the parallel voltage measured by the parallel voltage measuring means; and

broken wire detecting means for detecting whether a wire breakage in each of the power generator units occurs.

19. A method for driving a thermoelectric power generating apparatus, the thermoelectric power generating apparatus comprising:

a plurality of power generator units, each power generator unit including at least one thermocouple and being capable of mutually generating an equal output voltage;

a connection form switch for switching an electrical connection form of each one of the power generator units with respect to another of the power generator units between a serial connection and a parallel connection

a parallel voltage detector for measuring a parallel voltage when the plurality of power generator units are connected in parallel to each other;

a connection form detector for determining the connection form of all of the power generator units in one of three forms consisting of a serial connection, a parallel connection, and a combination of the serial and parallel connections, so as to generate a thermoelectric power according to a load connected to the thermoelectric power generating apparatus on the basis of a value of the parallel voltage measured by the parallel voltage measuring block; and

a broken wire detector for detecting whether a wire breakage in each of the power generator units occurs;

the method comprising the steps of;

measuring the parallel voltage of the power generator units connected in parallel with each other through the parallel voltage measuring block;

detecting whether a wire breakage in each of the power generator units occurs;

determining a thermoelectric power start time at which the thermoelectric power generating apparatus starts the thermoelectric power generation from the measured parallel voltage;

determining the connection form of the power generator units in the three forms; and

interconnecting the power generator units in the determined connection form to generate the thermoelectric power.

20. A method for driving a thermoelectric power generating apparatus as claimed in claim 19, wherein the steps of determining are executed simultaneously and wherein the detecting step is executed utilizing a value of the parallel voltage measured at the measuring step whenever the measuring step, the first and second determining steps, and the power generating step are repeated.