A device maintenance apparatus includes: a comparison target selector configured to select comparison targets of a device information of a device as a maintenance target; and a display configured to display a comparative information generated based on changes in the device information.

A turbine speed probe diagnostic system is provided. The turbine includes a speed probe and a speed reading circuit. A speed lead connects the speed probe and speed reading circuit together to transmit speed signals from the speed probe to the speed reading circuit. A speed probe diagnostic circuit is also provided for connection to the speed lead. An isolation switch is provided to isolate the speed probe diagnostic circuit during normal operation when the speed reading circuit is receiving speed signals from the speed probe. When no speed signals are being received, the isolation switch closes and the speed probe diagnostic circuit performs a test on the speed probe or speed lead.

A control system is provided for a turbine valve. The turbine valve has a first coil and a second coil to control or sense movement of a mechanical valve positioner. Two valve positioners are provided with each valve positioner having two drive circuits to drive the first and second coils. Switches are provided such that only one drive circuit is connected to each coil at a time. The control system may also include a hydraulic pilot valve section and a main hydraulic valve section. Feedbacks are used to determine a pilot valve error and a main valve error which are combined to determine a turbine valve error. The turbine valve error is repeatedly determined to minimize the error.

A turbine control system is provided for decreasing the response time between readings of the speed of the turbine and changing a valve position in response thereto. The speed control system includes a speed probe that detects the speed of the turbine and a turbine valve that controls the flow of fluid or gas from or to the turbine. A controller receives a speed signal from the speed probe and sends valve position commands to the turbine valve. The controller also sends support functions to the turbine valve. The controller sends the valve position commands at a faster rate than the support functions.

A speed control system and a power load balance detector for a turbine is provided. The speed control system includes a speed wheel with a plurality of teeth. A timer stores a time stamp when each of the teeth passes by a speed probe. A first speed estimate is determined for overspeed protection, and a second speed estimate is determined for operational speed control. The power load balance detector trips or shuts down the turbine when an unbalance is above a first threshold and the speed of the turbine is above a second threshold.

A breaker between two electrical circuits is provided that is closed when electrical properties in both of the electrical circuits are matching. Two check circuits are provided for comparing electrical properties of the two electrical circuits. Each of the check circuits sets a corresponding authorization to close the breaker. The breaker is only closed if both check circuits set an authorization to close the circuit.

A water quality monitoring system is disclosed including a sampling pipe that acquires steam that passes a bleed pipe that bleeds steam from a low pressure turbine to which steam of low pressure is supplied from among steam turbines, a steam inlet tank into which the steam acquired by the sampling pipe flows, a water quality measurement apparatus that measures the water quality of condensed water condensed from the steam flowed in the steam inlet tank, and a water quality diagnosis apparatus that diagnoses the water quality of the condensed water using a result of the measurement of the water quality measurement apparatus. The steam inlet tank is installed at a location higher than that of the water quality measurement apparatus such that the water quality measurement apparatus measures the water quality of the condensed water boosted to the atmospheric pressure utilizing the head difference.

Embodiments of the present disclosure include a method for controlling a power generation system, the method including: calculating, during operation of the power generation system, a target water level within a pressure vessel of the power generation system, the pressure vessel receiving a feedwater input and generating a steam output; calculating a flow rate change of the steam output from the pressure vessel; calibrating the target water level within the pressure vessel based on the output from mass flux through the pressure vessel, the mass flux through the pressure vessel being derived from the at least the feedwater input and the steam output; and adjusting an operating parameter of the power generation system based on the calibrated target water level within the pressure vessel.

A method and device for detecting and extracting a gaseous fluid contained in a closed loop operating on a Rankine cycle are provided. The loop includes a multiplicity of constituents with, successively, a circulation and compression pump for a working fluid, a heat exchanger associated with a hot source, an expansion machine, a cooling exchanger, a working fluid tank and circulation pipes connecting these constituents. The method and device measure the temperature (Trelle) and the pressure (Prelle) of the working fluid at a point of the loop when this loop is at rest, and, as soon as the measured pressure (Prelle) exceeds a threshold value (Pliquide satur) for a given ambient temperature (T), activate equipment for extracting the gaseous fluid in order to discharge it from the loop.

An efficiency evaluation method of an RCAES system is disclosed, and the method includes calculating electric energy charged by an electric power system in a compression process, calculating electric energy discharged to the electric power system in an expansion process, and calculating a ratio of the electric energy discharged in the expansion process to that charged in the compression process, and taking the ratio as an efficiency of the whole RCAES system; wherein gas in operation is ideal gas, air mass flow rates in the compression and expansion processes are known and constant in operation, an isothermal model is adopted for the CASV of which the temperature is the same with ambient circumstances, and the temperature and pressure of compressed air after throttling become constant. A corresponding system is also disclosed.