Rankine cycle power plant heat source control

Abstract

Provision is made in an organic rankine cycle power plant for modulating the flow of hot gases from a thermal source to the evaporator. The modulation device may be a blower on the downstream side of the evaporator or a valve on the upstream side thereof. The modulation device is controlled by generation of a digital signal to enable or disenable the modulation device and an analog signal for adjusting the position of the modulation device.

1 . A heat source control mechanism for use with an organic rankine cycle power plant of the type having in serial flow relationship, an evaporator, a turbine and a condenser, comprising:
 a thermal source for providing a flow of hot gases to a flow path passing through the evaporator;   at least one modulation device disposed within said flow path for selectively varying the flow of hot gases to the evaporator; and   a controller for selectively adjusting said modulation device.   
     
     
         2 . A heat source control mechanism as set forth in  claim 1  wherein said controller is adapted to provide a digital signal to said modulation device to selectively enable or disenable said device. 
     
     
         3 . A heat source control mechanism as set forth in  claim 1  wherein said controller is adapted to provide an analog signal for selectively adjusting the position of said at least one modulation device for the purpose of varying the flow of hot gases through the evaporator. 
     
     
         4 . A heat source control mechanism as set forth in  claim 1  wherein said thermal source includes a chimney or venturi for conducting the flow of hot gases from said thermal source to ambient, and inducing a reverse flow of ambient air through the evaporator. 
     
     
         5 . A heat source control mechanism as set forth in  claim 1  wherein said at least one modulation device comprises a blower fluidly connected on a downstream side of said evaporator. 
     
     
         6 . A heat source as set forth in  claim 5  wherein said thermal source includes a chimney or venture upstream of said evaporator. 
     
     
         7 . A heat source control mechanism as set forth in  claim 1  wherein said at least one modulation device comprises a valve fluidly connected on an upstream side of said of said evaporator. 
     
     
         8 . A heat source control mechanism as set forth in  claim 7  wherein said valve is normally open to fully bypass the flow of hot gases from said evaporator. 
     
     
         9 . A heat source control mechanism as set forth in  claim 8  wherein said valve is a diverter valve whose position is adjusted by said control to allow the flow of hot gases through said evaporator in a controlled manner. 
     
     
         10 . A heat source control mechanism as set forth in  claim 7  wherein said thermal source is pressurized. 
     
     
         11 . A heat source control mechanism as set forth in  claim 7  wherein said valve is a normally closed valve which prevents the flow of hot gases to the evaporator. 
     
     
         12 . A heat source control mechanism as set forth in  claim 11  wherein said control adjusts the position of said at least one modulation device to allow the flow of hot gases to the evaporator on a controlled basis. 
     
     
         13 . A heat source control mechanism as set forth in  claim 1  wherein said at least one modulation device comprises a blower on the downstream side of said evaporator and a valve on the upstream side thereof. 
     
     
         14 . A heat source control mechanism as set forth in  claim 13  wherein said control provides a digital signal to enable both said blower and said valve. 
     
     
         15 . A heat source control mechanism as set forth in  claim 13  wherein said control provides an analog signal to selectively vary the speed of the blower. 
     
     
         16 . A method of controlling the flow of hot gases from a heat source to an organic rankine cycle power plant of the type having in serial flow relationship, an evaporator, a turbine and a condenser, comprising the steps of
 delivering a flow of hot gases from a thermal source having particular pressure and flow characteristics to a flow path passing through the evaporator; and   selectively varying the flow of hot gases to the evaporator so as to accommodate the particular pressure and flow characteristics of said thermal source.   
     
     
         17 . A method as set forth in  claim 16  and including the step of providing a digital signal from a controller to a flow varying device to selectively enable or disenable said device. 
     
     
         18 . A method as set forth in  claim 16  and including the step of providing an analog signal from a controller for selectively adjusting the position of a flow varying device for the purpose of varying the flow of hot gases through the evaporator. 
     
     
         19 . A method as set forth in  claim 16  and including the step of conducting the flow of hot gases from said thermal source to ambient, rather than through the evaporator. 
     
     
         20 . A method as set forth in  claim 16  wherein the step of varying the flow is accomplished by way of a blower fluidly connected on a downstream side of said evaporator. 
     
     
         21 . A method as set forth in  claim 16  wherein the step of varying the flow is accomplished by way of a valve fluidly connected on an upstream side of said of said evaporator. 
     
     
         22 . A method as set forth in  claim 21  and including the step of placing said valve in a normally open position to fully bypass the flow of hot gases from said evaporator. 
     
     
         23 . A method as set forth in  claim 22  and including the step of adjusting the position of said valve by operation of said control to allow the flow of hot gases through said evaporator in a controlled manner. 
     
     
         24 . A method as set forth in  claim 21  and including the step of pressurizing said thermal source. 
     
     
         25 . A method as set forth in  claim 21  and including the step of placing said valve in a normally closed position to prevent the flow of hot gases to the evaporator. 
     
     
         26 . A method as set forth in  claim 25  and including the step of adjusting the position of said valve to allow the flow of hot gases to the evaporator on a controlled basis. 
     
     
         27 . A method as set forth in  claim 16  wherein the step of varying the flow is accomplished by way of a blower on the downstream side of said evaporator and a valve on the upstream side thereof. 
     
     
         28 . A method as set forth in  claim 27  and including the step of providing a digital signal to enable both said blower and said valve. 
     
     
         29 . A method as set forth in  claim 27  and including the step of providing an analog signal to selectively vary the speed of the blower.