A speed control method of direct current motor fans is revealed. The method used for starting and speed adjustment of the DC motor fan according to a temperature signal includes the following steps. First using a first voltage to start a DC motor fan during a start period and the first voltage is larger than the lowest voltage required for keeping the DC motor fan rotating. Then provide the DC motor fan with the lowest voltage which keeps the DC motor fan rotating during a low-load period after the start period. When a temperature represented by the temperature signal reaches a preset heat dissipation temperature range, a working voltage is adjusted proportionally and linearly according to the temperature signal for speed adjustment of the DC motor fan. The present method has advantages of high starting torque, noise cancellation, energy-saving, and low cost.

An operation management device includes a state acquiring unit that acquires a measurement value of a first state amount indicating an operation state of a power generation plant, a state updating unit that updates an estimation value of a second state amount, which indicates the operation state of the power generation plant and is a state amount different from the first state amount, based on the measurement value of the first state amount, and a managing unit that manages the operation state of the power generation plant based on the estimation value of the second state amount.

According to an aspect, a gas turbine engine includes a turbine section with a turbine case and a plurality of turbine blades within the turbine case. The gas turbine engine also includes an active clearance control system with an active clearance control cooling air supply, a valve pneumatically coupled to the active clearance control cooling air supply, and a controller. The controller is configured to determine an active cooling control schedule adjustment based on a condition of the gas turbine engine, operate the active clearance control system according to an active cooling control schedule as modified by the active cooling control schedule adjustment, apply a decay function to the active cooling control schedule adjustment to reduce an effect on the active cooling control schedule adjustment, and resume operating the active clearance control system according to the active cooling control schedule based on an active cooling control condition being met.

An oil pipe assembly for a gas turbine engine. The oil pipe assembly includes a first pipe that defines a first fluid passage between an oil supply and a bearing chamber, and a second pipe that houses the first pipe and defines a second fluid passage between the first pipe and the second pipe that is supplied with cooling air. The oil pipe assembly also includes a restrictor that extends from the second pipe and restricts the passage of fluid from the second fluid passage before it flows into a breather. Pressure and temperature sensors) are located adjacent the restrictor to detect and measure changes in air pressure and air temperature adjacent the restrictor from which a controller identifies whether a leak has occurred in the first pipe or the second pipe. A method for detecting a leak in the oil pipe assembly, and a gas turbine are also described.

A system includes a vertical molten sulfur pump assembly that includes a top portion adjacent to a first end of the vertical molten sulfur pump assembly and a bottom portion adjacent to a second end of the vertical molten sulfur pump assembly. A pump motor is disposed in the top portion, an impeller is disposed in the bottom portion within an impeller casing, and a shaft is disposed within a central column and connecting the pump motor with the impeller. A pump inlet is disposed at the second end below the impeller casing. The pump inlet and the impeller casing are configured to be immersed in molten sulfur. The vertical molten sulfur pump assembly is configured to pump the molten sulfur into the inlet and upwards through a discharge passageway by rotation of the impeller. A vibration sensor and a temperature sensor are disposed on an external surface of the bottom portion, on or proximate to the impeller casing and the pump inlet. The temperature sensor is configured to measure a temperature of the molten sulfur proximate to the pump inlet. The vibration sensor includes a substrate comprising a polymer and a resonant layer disposed on a surface of the substrate. The resonant layer includes an electrically conductive nanomaterial and is configured to produce a resonant response in response to receiving a radio frequency signal.

A motor drive control device 1 includes a drive voltage generation circuit 13 configured to generate a drive voltage Vin based on a first supply voltage Vdc inputted to a first terminal P1 and generate the drive voltage Vin based on a second supply voltage inputted to a second terminal P2 when a supply of the first supply voltage Vdc is stopped, a control circuit 21 configured to be operable by the drive voltage Vin, generate a drive control signal Sd based on a drive command signal Sc, generate a motor driving information signal So and output the motor driving information signal So from a third terminal P3 and a motor drive circuit 10 configured to output a drive signal to the motor 3, in which the control circuit 21 monitors the first supply voltage Vdc and outputs history information 300 relating to operation of the motor 3 from the third terminal P3 as the motor driving information signal So upon detecting that the supply of the first supply voltage Vdc is stopped.

Methods and systems for operating an aircraft engine having a compressor are described. The method comprises determining, based on actual operating parameters of the aircraft engine, a compressor mass flow limit for an aerodynamic stability of the aircraft engine; determining an actual compressor mass flow of the compressor of the aircraft engine, wherein the actual compressor mass flow is based on measured values of the aircraft engine; comparing the actual compressor mass flow to the compressor mass flow limit; and governing operation of the aircraft engine to cause an alternative compressor mass flow when the actual compressor mass flow reaches or is anticipated to reach the compressor mass flow limit.

An acquisition unit is configured to acquire measurement values of a target device. The measurement values that are acquired include at least a temperature and a flow rate of an input fluid to be input to the target device, and a temperature and a flow rate of an output fluid to be output from the target device. A correction unit is configured to obtain a correction measurement value by which the measurement values are corrected through thermal equilibrium calculations based on the measurement values. A distance calculation unit is configured to calculate a Mahalanobis distance with a factor of the correction measurement value.

A thermal management system includes a first heat source assembly including a first heat source exchanger, a first thermal fluid inlet line extending to the first heat source exchanger, and a first thermal fluid outlet line extending from the first heat source exchanger; a second heat source assembly including a second heat source exchanger, a second thermal fluid inlet line extending to the second heat source exchanger, and second a thermal fluid outlet line extending from the second heat source exchanger; a shared assembly including a thermal fluid line and a heat sink exchanger, the shared assembly defining an upstream junction in fluid communication with the first thermal fluid outlet line and second thermal fluid outlet line and a downstream junction in fluid communication with the first thermal fluid inlet line and second thermal fluid inlet line; and a controller configured to selectively fluidly connect the first heat source assembly or the second heat source assembly to the shared assembly.

Embodiments of the present disclosure include a method for controlling a power generation system, the method including: detecting a heat distribution across a component of a power generation system from a thermal output of the component, during operation of the power generation system; calculating a projected heat distribution across the component based on a library of modeling data for the power generation system; calculating whether a difference between the heat distribution and the projected heat distribution exceeds a thermal threshold; adjusting the power generation system in response to the difference exceeding the predetermined threshold, wherein the adjusting includes modifying an operating setting of the power generation system.