Abstract:
A conventional hydrogen-cooled electric generator having gland seals prevents the escape of hydrogen gas from the generator housing. A conventional seal oil system provides the gland seals with the necessary oil so as to perform their sealing function. Diagnostic apparatus is provided for the arrangement and includes a plurality of sensors which provide output signals indicative of certain parameters such as temperatures and pressures throughout the seal oil system. The output signals are provided to a diagnostic computer which, in a preferred embodiment, utilizes an expert system diagnostic routine for examining the sensor signals and deriving certain conclusions relative to the operating condition of the seal oil system. Various conclusions are additionally reached using operator-entered information from off-line sensors.
Abstract:
A pressure regulation circuit delivers pressurized fluid into a generator. The circuit includes pressure regulator structure and a primary valve. The pressure regulator structure outputs pressurized fluid at a predetermined output pressure that is greater than a desired operating pressure of the generator and less than a predetermined upper alarm pressure. The primary valve is downstream from the pressure regulator structure and is selectively opened and closed by a controller based on the pressure within the generator. The controller opens the primary valve to allow the pressurized fluid outputted from the pressure regulator structure to flow into the generator upon the pressure within the generator being at or below a predetermined lower limit. The controller closes the primary valve to prevent the pressurized fluid outputted from the pressure regulator structure from flowing into the generator upon the pressure within the generator being at or above a predetermined upper limit.
Abstract:
A system for providing seal oils to a gland seal that surrounds the shaft of a generator with the temperature differences between the oils minimized, as well maintained at a temperature which is greater than that for a bearing lubrication oil supply system. The temperature of the air-side seal oil is used as a reference and then the difference between the air- and hydrogen-side seal oil temperatures is used to control the hydrogen-side seal oil temperature. The air-side temperature is controlled by a separate controller using the bearing oil temperature as a reference. The system advantageously prevents thermal differential expansion from occurring in the generator shaft and gland seal, and eliminates the need for operator attention for seal oil temperature control.
Abstract:
The ratio of the pressure change across a portion of the ventilation system of a hydrogen cooled electric power generator to the pressure increase across a reference blower, preferably the purity blower, is compared to a base ratio to generate an alarm when the difference in ratios exceeds a predetermined amount indicative of a failure within the ventilation system.
Abstract:
A pressure regulation circuit delivers pressurized fluid into a generator. The circuit includes pressure regulator structure and a primary valve. The pressure regulator structure outputs pressurized fluid at a predetermined output pressure that is greater than a desired operating pressure of the generator and less than a predetermined upper alarm pressure. The primary valve is downstream from the pressure regulator structure and is selectively opened and closed by a controller based on the pressure within the generator. The controller opens the primary valve to allow the pressurized fluid outputted from the pressure regulator structure to flow into the generator upon the pressure within the generator being at or below a predetermined lower limit. The controller closes the primary valve to prevent the pressurized fluid outputted from the pressure regulator structure from flowing into the generator upon the pressure within the generator being at or above a predetermined upper limit.
Abstract:
A system for providing seal oils to a gland seal that surrounds the shaft of a generator with the temperature differences between the oils minimized. The temperature of one of the seal oils is utilized as a reference for controlling the oil temperature of the other seal oil. In particular, the temperature of the air-side seal oil is determined and utilized as a reference. The temperature of the hydrogen-side seal oil is determined, and a differentiator produces a signal based upon the difference between the air-side and hydrogen-side seal oils to control either the water flow rate to the hydrogen-side cooler, or to control mixing of cooled and uncooled oil in the hydrogen-side of the system. The system advantageously prevents thermal differential expansion from occurring in the generator shaft, and allows for the elimination of a controlled cooler in the air-side oil system. Further, the air-side oil can be suplied from the main lube oil system.
Abstract:
An apparatus for monitoring hydrogen leakage from a generator frame into the stator coil water cooling system. The monitor is designed to alert the operator should leakage exceed a rate of twenty cubic feet per day (20 cfd). A pressure relief valve set at four (4) psig and orifice are provided, along with a second relief valve having a higher setpoint than the first, such that pressure will increase in the holding tank if leakage exceeds 20 cfd setpoint of the orifice. A high pressure alarm, set at a level higher than the first relief valve but less than that of the second, will then sound to alert the operator to protect the system from an overly large or gross failure of the system. By continusouly monitoring a relatively small steady state leakage rate, the operator can be aware of a minor problem which can be corrected at a scheduled maintenance outage, before a gross failure of the system, requiring a costly shutdown of the turbine-generator, would otherwise occur.