Turbine inlet condition controlled organic rankine cycle

摘要

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.

主权项

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.