EPE Association: EPE 2011 - LS5f: Topic 08: Estimation Techniques

EPE 2011 - LS5f: Topic 08: Estimation Techniques
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2011 ECCE Europe - Conference > EPE 2011 - Topic 08: Measurements and Sensors > EPE 2011 - LS5f: Topic 08: Estimation Techniques

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   Laboratory evaluation of the VSD-based hybrid estimation method for the pump operational state
By Tero AHONEN, Jussi TAMMINEN, Jero AHOLA, Juha KESTILÄ [View]
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Abstract: Operational state of a centrifugal pump directly affects the resulting energy consumption of the pump. Frequency converters (VSDs) allow the sensorless estimation of the operational state of a centrifugal pump, offering new possibilities for the diagnostics and control of pumping systems. However, estimation of the pump operational state by the QP-curve-based estimation method cannot always provide accurate results for instance because of the flat QP characteristic curve shape. In the worst case, this may prevent the detection of inefficient or even harmful pump operation. In this paper, a hybrid method with improved accuracy for sensorless estimation of the pump operational state by a frequency converter is studied through laboratory measurements. It allows more accurate estimation of the pump operational state especially at low rotational speeds and relative flow rates compared with the sole use of the known QP-curve-based estimation method.

   Online STATCOM Load Estimation using Inverter Synchronized Sampler and Recursive Least-Squares
By Bjarte HOFF, Waldemar SULKOWSKI, Trond OSTREM [View]
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Abstract: In this paper, a state-space model of the power system is estimated as seen from the inverter using recursive least-squares (RLS). The inverter may function as a Static Synchronous Compensator (STATCOM), or connecting distributed energy sources to the grid. By using inverter synchronized sampling, measurement noise due to switching glitch are avoided. The method is well suited for online implementation in control design or smart grid applications. The method is verified by simulations and experiments using the estimated system as a one step predictor.

   SENSORLESS FLOW RATE ESTIMATION IN FREQUENCY-CONVERTER-DRIVEN FANS
By Jussi TAMMINEN, Tero AHONEN, Jero AHOLA, Juha KESTILÄ [View]
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Abstract: Fan systems account for approximately 11 \% of the industrial electricity consumption. Previous studies indicate that there is a significant energy savings potential in fan systems. Increase in the price of electricity has brought forth a need for easily implementable methods to measure the efficiency of fan systems. In this paper, a sensorless fan operating point estimation method is introduced and the limitations of the method are discussed. Operation of the sensorless estimation method is validated through laboratory measurements. It is found that the estimation method is accurate enough to be used for energy efficiency analyses and the detection of inefficient fan operation.

EPE 2011 - LS5f: Topic 08: Estimation Techniques
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2011 ECCE Europe - Conference > EPE 2011 - Topic 08: Measurements and Sensors > EPE 2011 - LS5f: Topic 08: Estimation Techniques
	[return to parent folder]

	Laboratory evaluation of the VSD-based hybrid estimation method for the pump operational state By Tero AHONEN, Jussi TAMMINEN, Jero AHOLA, Juha KESTILÄ	[View] [Download]
Abstract: Operational state of a centrifugal pump directly affects the resulting energy consumption of the pump. Frequency converters (VSDs) allow the sensorless estimation of the operational state of a centrifugal pump, offering new possibilities for the diagnostics and control of pumping systems. However, estimation of the pump operational state by the QP-curve-based estimation method cannot always provide accurate results for instance because of the flat QP characteristic curve shape. In the worst case, this may prevent the detection of inefficient or even harmful pump operation. In this paper, a hybrid method with improved accuracy for sensorless estimation of the pump operational state by a frequency converter is studied through laboratory measurements. It allows more accurate estimation of the pump operational state especially at low rotational speeds and relative flow rates compared with the sole use of the known QP-curve-based estimation method.

	Online STATCOM Load Estimation using Inverter Synchronized Sampler and Recursive Least-Squares By Bjarte HOFF, Waldemar SULKOWSKI, Trond OSTREM	[View] [Download]
Abstract: In this paper, a state-space model of the power system is estimated as seen from the inverter using recursive least-squares (RLS). The inverter may function as a Static Synchronous Compensator (STATCOM), or connecting distributed energy sources to the grid. By using inverter synchronized sampling, measurement noise due to switching glitch are avoided. The method is well suited for online implementation in control design or smart grid applications. The method is verified by simulations and experiments using the estimated system as a one step predictor.

	SENSORLESS FLOW RATE ESTIMATION IN FREQUENCY-CONVERTER-DRIVEN FANS By Jussi TAMMINEN, Tero AHONEN, Jero AHOLA, Juha KESTILÄ	[View] [Download]
Abstract: Fan systems account for approximately 11 \% of the industrial electricity consumption. Previous studies indicate that there is a significant energy savings potential in fan systems. Increase in the price of electricity has brought forth a need for easily implementable methods to measure the efficiency of fan systems. In this paper, a sensorless fan operating point estimation method is introduced and the limitations of the method are discussed. Operation of the sensorless estimation method is validated through laboratory measurements. It is found that the estimation method is accurate enough to be used for energy efficiency analyses and the detection of inefficient fan operation.