Abstract:
The present disclosure is directed to a method and apparatus for approximating a static head of a fluid transfer system including a fluid transfer device. The method can include determining a rotational speed and a power consumption of the fluid transfer device, determining a first set of data points, calculating a second set of data points on the basis of the first set of data points, determining a minimum rotational speed producing flow through the fluid transfer device on the basis of the second set of data points, and determining the static head on the basis of the minimum rotational speed.
Abstract:
A method and apparatus are disclosed for monitoring accumulation of dirt on an air filter of a ventilation system including the filter and a fan controlled by a frequency converter. An initial value for an operating parameter is determined. A present operating point is determined based on a characteristic curves, and the mechanical power and rotational speed of the fan. A present value for the operating parameter is determined based on the present operating point, and accumulation of dirt is determined on the air filter based on the initial and present values of the operating parameter.
Abstract:
A method and apparatus are disclosed for monitoring accumulation of dirt on an air filter of a ventilation system including the filter and a fan controlled by a frequency converter. An initial value for an operating parameter is determined. A present operating point is determined based on a characteristic curves, and the mechanical power and rotational speed of the fan. A present value for the operating parameter is determined based on the present operating point, and accumulation of dirt is determined on the air filter based on the initial and present values of the operating parameter.
Abstract:
A method and controller for operating pumps wherein each pump is modelled by a QH model indicating a high-efficiency region, a high-H region and a high-Q region and a rotational speed limit. A controller dynamically maintains a current set of operating pumps and controls their rotational speed (n). In steady-state operation, wherein the pumps operate in the high-efficiency region and below the rotational speed limit, all pumps of the current set are controlled together. If the pumps operate in the high-Q region or beyond the speed limit, a new pump is added to the current set, started and brought to a speed that produces flow. A balancing operation (12-3) follows the pump addition operation, wherein the speed of the pumps of the current set are adjusted for equal heads. If the pumps operate in the high-H region, a pump is removed from the current set of pumps.
Abstract:
A method and controller for operating pumps wherein each pump is modelled by a QH model indicating a high-efficiency region, a high-H region and a high-Q region and a rotational speed limit. A controller dynamically maintains a current set of operating pumps and controls their rotational speed (n). In steady-state operation, wherein the pumps operate in the high-efficiency region and below the rotational speed limit, all pumps of the current set are controlled together. If the pumps operate in the high-Q region or beyond the speed limit, a new pump is added to the current set, started and brought to a speed that produces flow. A balancing operation (12-3) follows the pump addition operation, wherein the speed of the pumps of the current set are adjusted for equal heads. If the pumps operate in the high-H region, a pump is removed from the current set of pumps.
Abstract:
A method is provided for detecting the correct rotational direction of a centrifugal apparatus. The method includes rotating the centrifugal apparatus in a first direction, acquiring first frequency data relating to the step of rotating the centrifugal apparatus in the first direction, rotating the centrifugal apparatus in a second direction, which is opposite to the first direction, and acquiring second frequency data relating to the step of rotating the centrifugal apparatus in the second direction. The method also includes detecting the correct rotational direction of the centrifugal apparatus based on comparing the first frequency data with the second frequency data, the comparison being carried out with respect to at least one significant frequency range. In each of the at least one significant frequency range, a smaller magnitude is interpreted as an indication of the correct rotational direction.
Abstract:
A method and apparatus for optimizing energy efficiency of a pumping system includes at least one pump that controls a fluid level in a reservoir. The method includes a system identification stage and an energy efficiency optimization stage. The system identification stage includes determining pump characteristics for the pump, operating the pump with a range of flow rate conditions, determining a set of data points, and calculating energy efficiency optimization characteristics. The energy efficiency optimization stage includes determining a present static head value, choosing a value for a pump control parameter, and operating the pump on the pump control parameter.