Variable Speed Gas Turbine Generation System and Method

Abstract

A power generation system comprises a heat collector, a turbine generator system having a turbine and at least one doubly fed induction generator, a heat exchanger, a gas holding tank, an energy storage unit and a load. The heat collector is coupled to and in fluid communication with the heat exchanger, which is in turn coupled to the turbine of the turbine generator system. The turbine is coupled to the doubly fed induction generator, which is then coupled to the load. A controller is communicatively coupled to the at least one doubly fed induction generator for maintaining a constant electrical output and frequency. Depending upon the electrical output load, the doubly fed induction generator can operate in varying speeds to achieve efficiency. To enhance the expansion of the gas, the turbine generator system can further include a pre-heater for preheating the gas to be heated and expanded by the heat exchanger.

1 . A power generation system comprising:
 a turbine generator system comprising a turbine;   at least one doubly fed induction generator directly coupled to the turbine;   a heat collector for receiving heat energy to produce a heated fluid, the heat energy generated by at least one of a heat source;   a heat exchanger configured to receive the heated fluid for heating and expanding a gas contained therein, the expanded gas being communicated to the turbine for converting the expanded gas into displacement motion for driving the at least one of a doubly fed induction generator for generating power therefrom; and   a controller communicatively coupled to the at least one doubly fed induction generator for maintaining the at least one doubly fed induction generator at a constant electrical output and frequency;   wherein the at least one doubly fed induction generator manages power provided to a load by based on the power requirement of the load at the constant electrical output voltage and frequency;   wherein the turbine runs freely at speeds governed by the heat transferred to the gas and the demand from the load at the constant electrical output voltage and frequency.   
     
     
         2 . The power generation system of  claim 1 , wherein the heat collector comprises a solar collector system for receiving solar thermal energy. 
     
     
         3 . The power generation system of  claim 2 , wherein the solar collector system comprises at least one solar collector for converting the solar thermal energy into heat energy to heat up the fluid. 
     
     
         4 . The power generation system of  claim 2 , wherein the solar collector system is a concentrated solar power (CSP) system. 
     
     
         5 . The power generation system of  claim 1 , wherein the fluid is at least one of oil, water, ammonia and Freon. 
     
     
         6 . The power generation system of  claim 1 , wherein the at least one heat source comprises at least one of biogas, biomass, natural gas, methane and waste heat. 
     
     
         7 . The power generation system as in  claim 1 , the turbine generator system further comprising a pre-heater for preheating the gas to be heated and expanded by the heat exchanger. 
     
     
         8 . The power generation system as in  claim 1 , further comprising a holding tank for containing the gas. 
     
     
         9 . The power generation system as in  claim 1  further comprising an energy storage unit. 
     
     
         10 . The power generation system as in  claim 1 , wherein the doubly fed induction generator generates power at various speeds of approximately 1,500 to 7,000 revolutions per minute. 
     
     
         11 . The power generation system as in  claim 1 , wherein the heated fluid operates at a temperature range of about 150° C. to 300° C. 
     
     
         12 . A method of managing a power system, the method comprising:
 heating a fluid in a heat collector;   channeling the heated fluid to a heat exchanger, the heat exchanger configured to receive the heated fluid for heating up and expanding a gas contained therein;   communicating the expanded gas to a turbine for converting the expanded gas into displacement motion for driving at least one of a doubly fed induction generator for generating power therefrom;   maintaining the at least one doubly fed induction generator at a constant electrical output and frequency by a controller; and   wherein the at least one doubly fed induction generator manages power provided to a load based on the power requirement of the load at the constant electrical output voltage and frequency;   wherein the turbine runs freely at speeds governed by the heat transferred to the gas and the demand from the load at the constant electrical output voltage and frequency.   
     
     
         13 . The method of  claim 10  further comprising:
 storing the gas in a holding tank; 
 preheating the gas; and 
 channeling the gas to the heat exchanger. 
 
     
     
         14 . The method of  claim 10 , further providing the heat collector with a solar collector system for receiving solar thermal energy. 
     
     
         13 . The method of  claim 12 , further providing the solar collector system with at least one solar collector for converting solar thermal energy into heat energy to heat up the fluid. 
     
     
         14 . The method of  claim 12 , wherein the solar collector system is a concentrated solar power system. 
     
     
         15 . The method of  claim 10 , wherein the fluid is at least one of oil, water, ammonia and Freon. 
     
     
         16 . The method of  claim 10 , further providing an energy storage unit. 
     
     
         17 . The method of  claim 10 , wherein the doubly fed induction generator generates power at speeds of approximately 1,500 to 7,000 revolutions per minute. 
     
     
         18 . The method of  claim 10 , wherein the heated fluid operates at a temperature range of about 150° C. to 300° C.