Apparatus for generating heat and electricity

• US 4,686,378 A
• Filed: 07/15/1985
• Issued: 08/11/1987
• Est. Priority Date: 07/15/1985
• Status: Expired due to Fees

• Current Assignee: Detroit Diesel Corporation (Mercedes-Benz Group AG)
• Original Assignee: ETA Thermal Systems Corporation
• Inventors: Sisk, Robert A.
• Primary Examiner(s): Salce, Patrick R.
• Assistant Examiner(s): VOELTZ, EMANUEL T
• Application Number:
  US06/754,638
• Time in Patent Office: 757 Days
• Field of Search: 290/2, 237/8 R, 237/12.1, 237/13, 165/13, 165/14, 165/48.1, 165/58, 74/645
• US Class Current: 290/2
• CPC Class Codes: F01K 17/02 for heating purposes, e.g. industrial, domestic F01K17/06 takes precedence; domestic- or space-heating systems, e.g. central-heating systems, in general F24D1/00, F24D3/00, F24D9/00
• CPC Class Codes: F02B 3/06 with compression ignition compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02
• CPC Class Codes: F02G 2260/00 Recuperating heat from exhaust gases of combustion engines and heat from cooling circuits
• CPC Class Codes: F02G 5/04 in combination with other waste heat from combustion engines
• CPC Class Codes: Y02E 20/14 Combined heat and power generation [CHP]
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An apparatus is disclosed for generating thermal and electrical energy outputs in response to thermal and electrical load requirements imposed thereon. The apparatus includes a variable speed power source and a mechanism for transferring thermal energy from the power source a coolant fluid. A generator is also provided and is driven by the power source to produce electrical energy for the electrical load. The output frequency of the generator is independent of the speed of the power source. A mechanism is also provided for extracting thermal energy from the coolant fluid and directing the thermal energy to the thermal load. Finally, a device is included for monitoring the loads and controlling the thermal and electrical outputs in response to the loads by independently varying the speed of the power source and the output frequency of the generator to provided desired thermal and electrical energy outputs.

Claims

1. An apparatus for generating thermal and electrical energy outputs in response to thermal and electrical load requirements imposed thereon, said apparatus comprising:

a variable speed power source;

means for transferring thermal energy from said power source to a coolant fluid;

a synchronous generator driven by said power source and adapted to produce an electrical energy output for said electrical load, the output frequency of said generator being independent of the speed of said power source;

means for extracting thermal energy from said fluid and directing said thermal energy output to said thermal load;

drive means for transferring the output of said power source to said generator and which permits the independently variable operation of said power source and said generator; and

means for monitoring said loads and controlling said thermal and electrical outputs independently, in response to variations in thermal and electrical loads caused by economic and external thermal and electrical supply factors, by independently varying the speed of said power source and the output frequency of said generator to provide said thermal and electrical outputs.

2. The apparatus as claimed in claim 1, wherein said drive means has a variable speed input and constant speed output to permit generation of said generator output frequency independent of the speed of said power source.

3. The apparatus as claimed in claim 2 wherein said variable speed input and constant speed output means comprises a gear train having variable speed drives.

4. The apparatus as claimed in claim 3, wherein said gear train comprises an epicyclic gear train.

5. The apparatus as claimed in claim 4, wherein said epicyclic gear train is coupled with an A.C. frequency control means.

6. The apparatus as claimed in claim 2, wherein said variable speed input and constant speed output means comprises a D.C. motor generator with an A.C. converter.

7. The apparatus as claimed in claim 2, wherein said variable speed input and the constant speed output means comprises a wound rotor generator.

8. The apparatus as claimed in claim 1, wherein said thermal energy extraction means comprises a primary heat exchanger adapted to transfer thermal energy from said coolant fluid to a second fluid directed to said thermal load.

9. The apparatus as claimed in claim 1, wherein said power source comprises an internal combustion engine.

10. The apparatus as claimed in claim 1, wherein said monitoring and controlling means maintains the speed of said power source and the frequency output of said generator automatically within a mathematically predetermined range providing optimum performance and economics of operation for said apparatus during normal thermal and electrical load requirements.

11. The apparatus as claimed in claim 1, wherein said apparatus is adapted to augment additional thermal and elecrical energy inputs provided to said load from sources independent of said apparatus, and wherein said monitoring and controlling means further includes means to monitor the thermal and electrical energy inputs provided by said sources and to adjust the thermal and electrical outputs of said apparatus in relation to the energy inputs available from said sources to provide optimum performance and economics of operation during normal energy load requirements.

12. The apparatus as claimed in claim 11, wherein said monitoring means further includes means to override the normal operating parameters of said monitoring and controlling means to provide maximum electrical energy output by said apparatus when a substantial drop in electrical voltage energy input provided by said sources is sensed by said monitoring and controlling means.

13. The apparatus as claimed in claim 1, wherein said coolant fluid conduction means comprises means for transferring heat energy from said power source and all its associated component portions to said fluid.

14. The apparatus as claimed in claim 2 wherein said drive means comprises a belt linkage.

15. The apparatus as claimed in claim 2 wherein said drive means comprises a hydraulic assembly.

16. An apparatus as claimed in claim 1 whereby said monitoring and controlling means comprises a computer.

34. The apparatus as claimed in claim 2, wherein said synchronous generator and said drive means comprises a D.C. motor generator with an A.C. converter.

35. The apparatus as claimed in claim 2, wherein said synchronous generator and said drive means comprises a wound rotor generator.

17. A device for cogenerating both heat and electricity in response to thermal and electrical loads imposed by a facility, in coordination with the electrical and thermal input from an external source, and in response to mathematically predetermined economic factors related to the operation of said device, said device comprising:

a variable speed internal combustion engine;

means for transferring thermal energy from said engine to a coolant fluid;

means for directing engine exhaust gas away from said engine;

a synchronous electrical generator driven by said engine to produce electricity for said electrical load, the output frequency of said generator being independent of the speed of said engine;

means interconnecting said engine and said generator and having variable speed input and constant speed output;

means for extracting heat from said fluid and exhaust gas and directing it to said thermal load;

means for monitoring the thermal and electrical loads of said facility, the thermal and electrical energy inputs from said outside source available to said facility, and economic factors related to the operation of said device; and

means for controlling the heat and electricity outputs in response to said loads, inputs, and factors by independently varying the speed of said engine and the output frequency of said generator to provide desired heat and electricity outputs.

18. The device as claimed in claim 17, wherein said variable speed input and constant speed output means comprises an epicyclic gear train.

19. The device as claimed in claim 18, wherein said epicyclic gear train is coupled with an A.C. frequency control mechanism.

20. The device as claimed in claim 17, wherein said heat extraction means comprises a primary heat exchanger adapted to transfer thermal energy from said coolant fluid and said exhaust gas to a second fluid directed to said thermal load.

21. The device as claimed in claim 20, wherein said heat extraction means further comprises a preliminary heat exchanger adapted to transfer thermal energy from said exhaust gas to said coolant fluid, and means to direct said coolant fluid from said preliminary heat exchanger to said primary exchanger to transfer said thermal energy to said second fluid.

22. The device as claimed in claim 17, wherein said monitoring and controlling means automatically maintains the speed of said engine and the frequency output of said generator within a mathematically predetermined range providing optimum performance and economics of operation, including shut-down of said device as needed, in response to said loads as well as the availability, efficiency and economy of the thermal and electrical energy available to said facility from said outside sources.

23. The device as claimed in claim 22, wherein said monitoring and controlling means further includes override means to provide maximum electrical output regardless of said economics of operation and optimum performance parameters when the electrical energy available to said facility from said outside source is substantially decreased.

24. The device as claimed in claim 17 wherein said interconnecting means comprises a belt assembly.

25. The device as claimed in claim 17 wherein said interconnecting means comprises a hydraulic assembly.

26. A device as claimed in claim 17 whereby said monitoring means and said controlling means comprises a computer.

27. The device claimed in claim 17 wherein said monitoring and controlling means includes override means to automatically operate said device at maximum electrical output in response to a substantial decrease in the electrical energy input available from said independent sources.

28. The device as claimed in claim 17, wherein said means for transferring thermal energy includes a heat exchanger for transferring said thermal energy to a second fluid adapted for travelling to and from said thermal load, and wherein said monitoring and controlling means comprises a computer to monitor said electric load and changes in temperature in said second fluid as it travels to and from said thermal load.

32. The device claimed in claim 17 whereby said monitoring and controlling means has the capability of reversing the electrical power flow back to said outside source.

29. A method for generating both thermal and electrical energy outputs using an internal combustion engine and a synchronous electrical generator in response to thermal and electrical loads of a facility, to the electric power and thermal input from an external source, and to economic factors related to efficient application of said method, said method comprising:

interconnecting said generator with said engine to drive said generator so as to permit said generator to maintain an electrical output independent of the operation of said engine;

operating said engine;

transferring thermal energy from said engine to a coolant fluid;

extracting the thermal energy from said fluid and directing it to said thermal load;

generating an electrical output from said generator up to the maximum constant output of said generator;

monitoring the thermal and electrical loads of said facility and the electrical and thermal input from said external source, and calculating and incorporating economic facctors related to the efficient application of said method; and

controlling the thermal and electrical energy outputs in response to said loads, said input, and said economic factors by independently varying the speed of said engine and the output frequency of said generator to provide desired thermal and electrical energy outputs.

30. The method as claimed in claim 29, wherein the thermal and electrical energy inputs provided from said external source are monitored, and wherein the normal facility load requirement parameters are automatically overridden to provide maximum electrical energy output by said generator when the independent electrical energy input from said external source has decreased substantially below the electrical energy requirement of said facility.

31. The method as claimed in claim 29, wherein normal electrical and thermal load requirements of said facility are automatically overridden to provide maximum electrical energy output by said generator when said electric power input from an external source has decreased substantially below the electrical energy requirement of said facility.

33. The method as claimed in claim 29, wherein the speed of the engine and the frequency output of the generator are automatically maintained within a range which provides optimum performance and economics of operation in response to said loads, input, and factors during normal facility load requirements.