There is disclosed a heat engine 10 comprising: a heat exchanger 12 to transfer heat from a heat source 100 to a working fluid; a positive displacement expander 16 configured to receive inlet working fluid from the heat exchanger 12 and discharge expanded working fluid as a multiphase fluid so that there is an overall volumetric expansion ratio between the expanded working fluid and the inlet working fluid which is a function of an inlet dryness of the inlet working fluid; a variable expansion valve 14 disposed between the heat exchanger 12 and the expander 16, the valve being configured to introduce a variable pressure drop in the working fluid to vary the inlet dryness; and a controller 30 configured to maintain the overall volumetric expansion ratio by controlling the valve 14 to compensate for variable heat transfer to or from the working fluid.

There is disclosed a heat engine 10 comprising: a heat exchanger 12 to transfer he at from a heat source 100 to a working fluid; a positive displacement expander 16 configured to receive inlet working fluid from the heat exchanger 12 and discharge expanded working fluid as a multiphase fluid so that there is an overall volumetric expansion ratio between the expanded working fluid and the GC inlet working fluid which is a function of an inlet dryness of the inlet working fluid; a variable expansion valve 14 disposed between the heat exchanger 12 and the expander 16, the valve being configured to introduce a variable pressure drop in the working fluid to vary the inlet dryness; and a controller 30 configured to maintain the overall volumetric expansion ratio by controlling the valve 14 to compensate for variable heat transfer to or from the working fluid.

Systems and methods to control power plant operation via control of turbine run-up and acceleration are disclosed. According to one embodiment of the disclosure, a method of controlling a turbine in a power plant can be provided. The method may include receiving an operating pressure of a condenser associated with a power plant; receiving a rotor speed of a turbine associated with the power plant; receiving a last stage blade (LSB) protection limit for the turbine; based at least in part on the operating pressure of the condenser, the rotor speed of the turbine, and the LSB protection limit, allowing, via a control system, a run-up of the turbine. The method may further include: receiving a rotor speed gradient of the turbine; receiving one or more critical speed ranges associated with the rotor speed of the turbine; and based at least in part on the operating pressure of the condenser, the rotor speed, the rotor speed gradient, and the one or more critical speed ranges, regulating, via the control system, at least one of: the rotor speed of the turbine and the rotor speed gradient of the turbine.

Systems and methods to control power plant operation via control of turbine run-up and acceleration are disclosed. According to one embodiment of the disclosure, a method of controlling a turbine in a power plant can be provided. The method may include receiving an operating pressure of a condenser associated with a power plant; receiving a rotor speed of a turbine associated with the power plant; receiving a last stage blade (LSB) protection limit for the turbine; based at least in part on the operating pressure of the condenser, the rotor speed of the turbine, and the LSB protection limit, allowing, via a control system, a run-up of the turbine. The method may further include: receiving a rotor speed gradient of the turbine; receiving one or more critical speed ranges associated with the rotor speed of the turbine; and based at least in part on the operating pressure of the condenser, the rotor speed, the rotor speed gradient, and the one or more critical speed ranges, regulating, via the control system, at least one of: the rotor speed of the turbine and the rotor speed gradient of the turbine.

Systems and methods to control power plant operation via control of turbine run-up and acceleration are disclosed. According to one embodiment of the disclosure, a method of controlling a turbine in a power plant can be provided. The method may include receiving an operating pressure of a condenser associated with a power plant; receiving a rotor speed of a turbine associated with the power plant; receiving a last stage blade (LSB) protection limit for the turbine; based at least in part on the operating pressure of the condenser, the rotor speed of the turbine, and the LSB protection limit, allowing, via a control system, a run-up of the turbine. The method may further include: receiving a rotor speed gradient of the turbine; receiving one or more critical speed ranges associated with the rotor speed of the turbine; and based at least in part on the operating pressure of the condenser, the rotor speed, the rotor speed gradient, and the one or more critical speed ranges, regulating, via the control system, at least one of: the rotor speed of the turbine and the rotor speed gradient of the turbine.

A method of controlling a thermal power plant for electricity generation, said power plant comprising at least one heat source to supply thermal energy to a working fluid circulation circuit. The circuit comprises a high pressure turbine mechanically connected to an electricity generator, a high pressure regulating valve controlling the steam supply to said high pressure turbine from a high pressure superheater associated with a high pressure storage tank. The fluid supply to said high pressure storage tank from a high pressure steam generator is controlled by a high pressure supply valve, and, in response to a need for additional electrical power, the opening of the high pressure regulating valve is increased the opening of the high pressure supply valve is reduced.

A method of controlling a thermal power plant for electricity generation, said power plant comprising at least one heat source to supply thermal energy to a working fluid circulation circuit. The circuit comprises a high pressure turbine mechanically connected to an electricity generator, a high pressure regulating valve controlling the steam supply to said high pressure turbine from a high pressure superheater associated with a high pressure storage tank. The fluid supply to said high pressure storage tank from a high pressure steam generator is controlled by a high pressure supply valve, and, in response to a need for additional electrical power, the opening of the high pressure regulating valve is increased the opening of the high pressure supply valve is reduced.