초록 ▼

A pressure sensor measures an organic Rankine cycle (ORC) working fluid pressure in front of a radial inflow turbine, while a temperature sensor measures an ORC working fluid temperature in front of the radial inflow turbine. A controller responsive to algorithmic software determines a superheated t

A pressure sensor measures an organic Rankine cycle (ORC) working fluid pressure in front of a radial inflow turbine, while a temperature sensor measures an ORC working fluid temperature in front of the radial inflow turbine. A controller responsive to algorithmic software determines a superheated temperature of the working fluid in front of the radial inflow turbine based on the measured working fluid pressure and the measured working fluid temperature. The controller then manipulates the speed of a working fluid pump, the pitch of turbine variable inlet guide vanes when present, and combinations thereof, in response to the determined superheated temperature to maintain the superheated temperature of the ORC working fluid in front of the radial inflow turbine close to a predefined set point. The superheated temperature can thus be maintained in the absence of sensors other than pressure and temperature sensors.

대표청구항 ▼

1. A method of controlling an organic Rankine cycle (ORC) superheated temperature, the method comprising: measuring ORC working fluid pressure at the inlet side of a radial inflow turbine; measuring ORC working fluid temperature at the inlet side of the radial inflow turbine; determining a superheat

1. A method of controlling an organic Rankine cycle (ORC) superheated temperature, the method comprising: measuring ORC working fluid pressure at the inlet side of a radial inflow turbine; measuring ORC working fluid temperature at the inlet side of the radial inflow turbine; determining a superheated temperature at the inlet side of the radial inflow turbine based on the measured working fluid pressure, the measured working fluid temperature, and a saturated vapor line temperature of the working fluid;manipulating at least one of the speed of an ORC working fluid pump, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to the determined superheated temperature to substantially maintain the superheated temperature of the working fluid at the inlet side of the radial inflow turbine at a predefined set point;controlling at least one of the operating the speed of the radial inflow turbine, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to a set point map, wherein the set point map comprises turbine input/output pressure ratio data and turbine mass flow data;measuring a working fluid mass flow at the inlet side of the radial inflow turbine; and manipulating at least one of the speed of the pump, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to the measured working fluid mass flow, and a working fluid mass flow set point based on the determined superheated temperature, such that working fluid mass flow characteristics supersede the determined superheated temperature to directly manipulate at least one of the pump speed, the pitch of the turbine variable inlet guide vanes, and combinations thereof, to substantially maintain the working fluid superheated temperature at the inlet side of the radial inflow turbine at a predefined set point. 2. The method according to claim 1, further comprising: controlling at least one of the operating speed of the radial inflow turbine, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to an optimizing algorithm, wherein the optimizing algorithm is configured to seek maximum turbine power output by varying at least one of the turbine speed, the pitch of the turbine variable inlet guide vanes, and combinations thereof, and further wherein the optimizing algorithm is configured to track maximum turbine output power points for changing ambient operating conditions; andcontinuously optimizing the set point map in response to corresponding maximum turbine power output data and corresponding maximum turbine output power point data. 3. An organic Rankine cycle (ORC) control system comprising: at least one pressure sensor configured to measure ORC working fluid pressure at the inlet side of a radial inflow turbine;at least one temperature sensor configured to measure ORC working fluid temperature at the inlet side of the radial inflow turbine;an optimizing controller comprising an optimizing algorithm, wherein the radial inflow turbine is configured to operate in response to an the optimizing algorithm, and wherein the optimizing algorithm is configured to seek maximum turbine power output by varying at least one of the turbine speed, turbine variable inlet guide vane pitch when the turbine comprises variable inlet guide vanes, and combinations thereof;a superheat controller configured to: determine a superheated temperature at the inlet side of the radial inflow turbine based solely on the measured working fluid pressure, the measured working fluid temperature, and a saturated vapor line temperature of the working fluid, andmanipulate at least one of the speed of a working fluid pump, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to the determined superheated temperature to substantially maintain the superheated temperature of the working fluid at the inlet side of the radial inflow turbine at a predefined set point;a mass flow controller responsive solely to a working fluid mass flow set point based on the determined superheated temperature, a working fluid pressure at the output side of the pump; anda working fluid pressure at the inlet side of the pump, such that the mass flow controller supersedes the superheat controller to directly manipulate at least one of the pump speed, the pitch of the turbine variable inlet guide vanes, and combinations thereof, to substantially maintain the superheated temperature at the inlet side of the radial inflow turbine at a predefined set point. 4. The ORC control system according to claim 3, wherein the superheat controller further comprises a lookup table comprising saturated vapor line temperatures as a function of saturated vapor line pressures to provide the saturated vapor line temperature of the working fluid. 5. The ORC control system according to claim 3, further comprising a set point map for determining at least one of an operating speed of the radial inflow turbine, a turbine variable inlet guide vane pitch when the turbine comprises variable inlet guide vanes, and combinations thereof. 6. The ORC control system according to claim 5, wherein the set point map comprises turbine input/output pressure ratio data and turbine mass flow data. 7. The ORC control system according to claim 3, wherein the optimizing algorithm is configured to track maximum turbine output power points for changing ambient operating conditions. 8. An organic Rankine cycle (ORC) control system comprising: at least one pressure sensor configured to measure ORC working fluid pressure at the inlet side of a radial inflow turbine;at least one temperature sensor configured to measure ORC working fluid temperature at the inlet side of the radial inflow turbine;an optimizing controller comprising an optimizing algorithm, wherein the radial inflow turbine is configured to operate in response to an the optimizing algorithm, and wherein the optimizing algorithm is configured to seek maximum turbine power output by varying at least one of the turbine speed, turbine variable inlet guide vane pitch when the turbine comprises variable inlet guide vanes, and combinations thereof;a superheat controller configured to: determine a superheated temperature at the inlet side of the radial inflow turbine based solely on the measured working fluid pressure, the measured working fluid temperature, and a saturated vapor line temperature of the working fluid, andmanipulate at least one of the speed of a working fluid pump, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to the determined superheated temperature to substantially maintain the superheated temperature of the working fluid at the inlet side of the radial inflow turbine at a predefined set point;a mass flow sensor configured to measure working fluid mass flow at the inlet side of the radial inflow turbine; anda mass flow controller responsive solely to the measured working fluid mass flow, and a working fluid mass flow set point based on the determined superheated temperature, such that the mass flow controller supersedes the superheat controller to directly manipulate at least one of the pump speed, the pitch of the turbine variable inlet guide vanes, and combinations thereof, to substantially maintain the superheated temperature at the inlet side of the radial inflow turbine at a predefined set point. 9. An organic Rankine cycle (ORC) plant comprising: an evaporator configured to receive a working fluid from a pump and to generate a vapor stream there from;a radial inflow turbine configured to receive the vapor stream and to generate power and an expanded stream there from;a condenser configured to receive the expanded stream and to generate the working fluid there from, wherein the working fluid and the vapor stream together form a closed ORC loop;at least one pressure sensor configured to measure working fluid pressure at the inlet side of the radial inflow turbine;at least one temperature sensor configured to measure working fluid temperature at the inlet side of the radial inflow turbine;a set point map for determining at least one of an operating speed of the radial inflow turbine, a turbine variable inlet guide vane pitch when the turbine comprises variable inlet guide vanes, and combinations thereof, wherein the set point map comprises turbine input/output pressure ratio data and turbine mass flow data;a superheat controller configured to: determine a superheated temperature at the inlet side of the radial inflow turbine based solely on the measured working fluid pressure, the measured working fluid temperature, and a saturated vapor line temperature of the working fluid, andmanipulate at least one of the speed of the pump, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to the determined superheated temperature to substantially maintain the superheated temperature at the inlet side of the radial inflow turbine at a predefined set point; anda mass flow controller responsive solely to a working fluid mass flow set point based on the determined superheated temperature, a working fluid pressure at the output side of the pump, and a working fluid pressure at the inlet side of the pump, such that the mass flow controller supersedes the superheat controller to directly manipulate at least one of the pump speed, the pitch of the turbine variable inlet guide vanes, and combinations thereof, to substantially maintain the superheated temperature at the inlet side of the radial inflow turbine at a predefined set point. 10. The ORC plant according to claim 9, wherein the superheat controller further comprises a lookup table comprising saturated vapor line temperatures as a function of saturated vapor line pressures to provide the saturated vapor line temperature of the working fluid. 11. The ORC plant according to claim 9, further comprising: a turbine inlet valve; andturbine bypass valve, wherein the turbine inlet valve is configured to remain closed and the turbine bypass valve is configured to remain open during wet turbine operating conditions. 12. The ORC plant according to claim 9, further comprising an optimizing controller comprising an optimizing algorithm, wherein the radial inflow turbine is configured to operate in response to the optimizing algorithm. 13. The ORC plant according to claim 12, wherein the optimizing algorithm is configured to seek maximum turbine power output by varying at least one of the turbine speed, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof. 14. The ORC plant according to claim 12, wherein the optimizing algorithm is configured to track maximum turbine output power points for changing ambient operating conditions. 15. An organic Rankine cycle (ORC) plant comprising: an evaporator configured to receive a working fluid from a pump and to generate a vapor stream there from;a radial inflow turbine configured to receive the vapor stream and to generate power and an expanded stream there from;a condenser configured to receive the expanded stream and to generate the working fluid there from, wherein the working fluid and the vapor stream together form a closed ORC loop;at least one pressure sensor configured to measure working fluid pressure at the inlet side of the radial inflow turbine;at least one temperature sensor configured to measure working fluid temperature at the inlet side of the radial inflow turbine;a set point map for determining at least one of an operating speed of the radial inflow turbine, a turbine variable inlet guide vane pitch when the turbine comprises variable inlet guide vanes, and combinations thereof, wherein the set point map comprises turbine input/output pressure ratio data and turbine mass flow data;a superheat controller configured to: determine a superheated temperature at the inlet side of the radial inflow turbine based solely on the measured working fluid pressure, the measured working fluid temperature, and a saturated vapor line temperature of the working fluid, andmanipulate at least one of the speed of the pump, the pitch of turbine variable inlet guide vanes when the turbine comprises variable inlet guide vanes, and combinations thereof, in response to the determined superheated temperature to substantially maintain the superheated temperature at the inlet side of the radial inflow turbine at a predefined set point;a mass flow sensor configured to measure working fluid mass flow at the inlet side of the radial inflow turbine; anda mass flow controller responsive solely to the measured working fluid mass flow and a working fluid mass flow set point based on the determined superheated temperature, such that the mass flow controller supersedes the superheat controller to directly manipulate at least one of the pump speed, the pitch of the turbine variable inlet guide vanes, and combinations thereof, to substantially maintain the superheated temperature at the inlet side of the radial inflow turbine at a predefined set point.