A pneumatic system operation control device for variable control of the rotation speed of an electric motor for driving an air-compressor such that constantly supplied pressure to a terminal device is achieved in accordance with a discharge pressure measurement value of the air-compressor and a supply pressure measurement value to the terminal device. The control device: stores the discharge pressure measurement value and the supply pressure measurement value; and, upon receiving input of an air pipe network model composed of data for calculating a flow of air in an air pipe network, calculates a flow rate of air supplied to the terminal device and an update value of a control setting value, and updates the control setting value to be used for variable control on the basis of the update value.

The utilization of hydro-generation technology is provisioned inside of water distribution systems within large urban buildings that require water pressure reduction. These micro-hydro-generators reduce the water pressure for tenant use and converts the energy into electricity to be used or sold.

The utilization of hydro-generation technology is provisioned inside of water distribution systems within large urban buildings that require water pressure reduction. These micro-hydro-generators reduce the water pressure for tenant use and converts the energy into electricity to be used or sold.

The present invention is directed to a method for controlling the outlet temperature of an oil injected compressor or vacuum pump comprising a compressor or vacuum element provided with a gas inlet, an element outlet, and an oil inlet, said method comprising the steps of: measuring the outlet temperature at the element outlet; and controlling the position of a regulating valve in order to regulate the flow of oil flowing through a cooling unit connected to said oil inlet; whereby the step of controlling the position of the regulating valve involves applying a fuzzy logic algorithm on the measured outlet temperature; and in that the method further comprises the step of controlling the speed of a fan cooling the oil flowing through the cooling unit by applying the fuzzy logic algorithm and further based on the position of the regulating valve.

A fan failure backup apparatus includes a first fan module and a second fan module. When a second control unit of the second fan module realizes that the first fan module is failed through a first control unit of the first fan module, and the second control unit realizes that the second fan module is not failed, the second control unit controls the second fan module to additionally enhance a pressure-flow characteristic of a second fan unit of the second fan module.

A system includes a fluid pump and a first pressure sensor disposed on or near an inlet of the fluid pump. The system further includes a second pressure sensor disposed on or near an outlet of the fluid pump and a control system. The control system includes a processor configured to receive a first signal from the first pressure sensor. The processor is further configured to receive a second signal from the second pressure sensor, and to derive a pump slip measure based on the first signal and the second signal.

A method for controlling multi-stage centrifugal compressors is provided. The method includes, for each stage of the compressor, defining a Mach ratio and impeller diameter, calculating a minimum required motor drive frequency to operate free from surge conditions for a current head factor and flow reduction device position, and adjusting the flow reduction device position while maintaining an actual motor drive frequency at a acceptable level to achieve a leaving chilled water temperature set point. The method also includes measuring a suction pressure and a discharge pressure and calculating a saturated suction temperature and a saturated discharge temperature for each stage of the compressor. The method further includes calculating an actual minimum motor drive frequency that is the greater of a first actual minimum motor drive frequency and a second actual minimum motor drive frequency associated with a first compressor stage and a second compressor stage of the compressor, respectively.

A pneumatic system operation control device for variable control of the rotation speed of an electric motor for driving an air-compressor such that constantly supplied pressure to a terminal device is achieved in accordance with a discharge pressure measurement value of the air-compressor and a supply pressure measurement value to the terminal device. The control device: stores the discharge pressure measurement value and the supply pressure measurement value; and, upon receiving input of an air pipe network model composed of data for calculating a flow of air in an air pipe network, calculates a flow rate of air supplied to the terminal device and an update value of a control setting value, and updates the control setting value to be used for variable control on the basis of the update value.

Disclosed is a system for controlling a water turbine generator for waterworks, which monitors and controls a plurality of water turbine generators, provided in a water pipe, for waterworks in real time to integratedly operate the water turbine generators, contributes to stably generate and secure power, and increases an efficiency of the water turbine generators through integrated management. The system for controlling a water turbine generator for waterworks includes an integration control system configured to establish a power generation driving plan, based on a target amount of energy collected by a plurality of water turbine generators and a driving range of each of the plurality of water turbine generators, and a power generation unit configured to generate power through generation of power by a water turbine according to control based on the power generation driving plan, measure an amount of generated power, an amount and a pressure of water flowing into the plurality of water turbine generators, and an amount and a pressure of water flowing out from the plurality of water turbine generators, and supply a result of the measurement to the integration control system.

A method (30) of controlling fuel flow in a gas turbine engine. First, detect a surge condition. Set fuel flow demand (W.sub.f.sub._.sub.D) proportional to compressor discharge pressure (P.sub.30). Detect actual fuel flow (W.sub.f.sub._.sub.A). Then apply an enhanced schedule (50) for fuel flow demand (W.sub.f.sub._.sub.D) while fuel flow demand (W.sub.f.sub._.sub.D) is less than a predefined proportion (k) of actual fuel flow (W.sub.f.sub._.sub.A). Also a gas turbine engine (10), fuel flow system (68) and fuel flow control system (76) each implementing the method (30).