EPE Association: EPE 2011 - DS3i: Topic 13: Energy Efficiency, Energy Saving Issues in System Components

EPE 2011 - DS3i: Topic 13: Energy Efficiency, Energy Saving Issues in System Components
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2011 ECCE Europe - Conference > EPE 2011 - Topic 13: Energy efficiency; energy saving issues in system components > EPE 2011 - DS3i: Topic 13: Energy Efficiency, Energy Saving Issues in System Components

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   Combined Solar and AC Mains Powered Lighting System
By Ulrich BOEKE, Matthias WENDT, Lennart YSEBOODT [View]
[Download]

Abstract: An experiment is presented that uses solar direct current (DC) in an AC mains powered 48 V DC power grid to reduce the AC power consumption of lighting systems in professional buildings. Measured annual AC mains power has been reduced by 15 \% for lighting systems with a combined DC solar and AC mains supply compared with a pure AC mains supplied lighting reference system.

   Efficiency improvement in DC and AC motor powered electric vehicles
By Ioannis KARATZAFERIS, Lampros LAMPROPOULOS, Emmanuel TATAKIS [View]
[Download]

Abstract: Electric vehicles seem to be a solution against the greenhouse gasses emission problem. The major problem of these vehicles is low autonomy, due to the low energy density of the batteries, compared to gasoline. A way of dealing with this problem is to increase the vehicle’s efficiency, by minimizing the power losses. In this paper, ways of minimizing the power losses for DC and AC motor powered vehicles via adjusting the gear ratio and the motor’s magnetic flux are studied. To do so, the losses of all parts of the electromechanic system are calculated as a function of the gear ratio λ, and the motor's magnetic flux CΦ, with the vehicle's speed and resultant force as parameters. It can be proved that for each pair of parameters there is an optimum set (CΦ, λ) that minimizes the vehicle's losses. Finally, the theoretical analysis is verified by experimental results.

   Energy Efficient Storage Systems in the DC Link for the Drive Unit of Machine Tools
By Artem KOLESNIKOV, Reimund NEUGEBAUER, Mark RICHTER [View]
[Download]

Abstract: The research of energy storage systems in the DC link of a machine tool is focused on the choice of the appropriate type of the energy storage system (passive or active) and its control strategy considering better energy efficiency. For the control strategy of the DC/DC converter two ways were taken into account: the proportional-integral and predictive control strategies. The energy consumption model of the drive group was developed in Matlab/SimPowerSystems for quantitative comparisons of the proposed energy storage systems. The model was validated by measurements of energy consumption in the drive unit of a machining centre.

   Extended-Flux Model with Core-loss Resistance of Synchronous Reluctance Motors andTorque Estimation without Core Loss Measurement and Position Encoder
By Masaru HASEGAWA, Hiroki KITAHARA [View]
[Download]

Abstract: This paper proposes an extended-flux model with core-loss resistance of synchronous reluctance motors (SynRMs) and precise torque estimation without core-loss measurement and position encoder. The proposed torque estimation is useful for precise maximum torque per ampere (MTPA) control of position sensorless controlled SynRMs, which is achieved with the assistance of active and reactive powers.

   High Efficient Winding Drives with Continuous Variable Transmission (CVT)
By Kenneth BENATH, Wilfried HOFMANN, Volkmar MÜLLER [View]
[Download]

Abstract: This paper shows that winding drives in combination with a continuous variable transmission (CVT) will lead to reduced rated power as well as an increased efficiency of the electrical drive. First practical experiments with imitation of a winding operation were performed to verify the theoretical investigations.

   Multilevel NPC inverter for low-voltage applications
By Rudolf MECKE [View]
[Download]

Abstract: Multilevel inverter topologies are an alternative for a wide range of low voltage electrical drives. In the low voltage range (<1000 V) highly optimised switches with lower conduction and switching losses are available. For 550 V DC link voltage the power semiconductor losses of a two-level VSI with 1200 V-IGBT and a neutral-point-clamped three-level VSI in the power range between 7 to 35 kW are compared. The comparison is carried out by calculation with a linear approximation for conduction and switching losses. The calculated results are proved by simulation with the real loss curves from the manufacturers. The simulated losses are higher than the calculated especially for operation points below the rated power. Therefore, the calculation of losses which is commonly used by the power semiconductor manufacturers is not sufficient for variable loads. At 20 kHz switching frequency and an electrical power of 35 kW the semiconductor losses of the three-level inverter are 38 \% lower compared to the two-level inverter. At 7 kW electrical power the reduction of losses is even 66 \%. The further increase of the inverter levels (four- and five-level) only leads to a small improvement of the motor current quality. Moreover, suitable power semiconductors (IGBT or MOSFET) with 300 V blocking voltage are not available for five-level inverters. Therefore, four- and five level inverters cannot be included in the losses calculation within this paper. Perhaps in the near future the five-level inverter leads to a further improvement in the inverter efficiency.

   REAL TIME IMPLEMENTATION OF SUBOPTIMAL CONTROL POSITION DRIVE SYSTEM WITH INDUCTION MACHINE
By Munteanu TRAIAN, Rosu EMIL, Paduraru ROMEO, Dumitriu TEODOR, Culea MIHAI [View]
[Download]

Abstract: This paper illustrates the importance of control on energy saving opportunity for electrical drives systems. The paper’s objective is to present a real time implementation of suboptimal control law for an electrical positioning system with induction machine at constant flux. The suboptimal control is based on numerical integration of the Matrix Riccati Differential Equation (MRDE).

   Smoothing Control of Wind Farm Output Fluctuation by New Scheme with Energy Storage System
By Rion TAKAHASHI, Masachika NAKATANI, Junji TAMURA, Muyeen S.M., Masatoshi SUGIMASA, Akiyoshi KOMURA, Motoo FUTAMI, Masaya ICHINOSE, Kazumasa IDE [View]
[Download]

Abstract: Electrical power generation from wind power is increasing rapidly nowadays. Therefore, wind farm output power fluctuation due to wind speed variations is becoming the major concern for Transmission System Operators (TSOs) or grid companies. As a result, it is needed to connect an energy storage system (ESS) to wind farm through power converters to smoothen the wind farm output fluctuations. As power losses occur in the power converters, it is important to reduce the losses to achieve effective use of renewable energy. In this paper, a new connection scheme of ESS to wind farm is proposed in which ESS is connected to the DC bus circuit of wind generator without using a PWM based DC-DC converter. Comparative analysis of the loss characteristics between the proposed system and the conventional one in which ESS is connected to the DC bus circuit with using a PWM based DC-DC converter is presented. The proposed system can simplify overall control scheme and improve the efficiency considerably. The loss characteristics are studied by simulation analyses on the laboratory standard power system software, PSCAD/EMTDC, using the practical (measured) wind speed data.

   Thermal modelling to analyze the effect of cell temperature on PV modules energy efficiency
By Florian ROMARY, Adelphe CALDEIRA, Sebastien JACQUES, Ambroise SCHELLMANNS [View]
[Download]

Abstract: In this paper, a one-dimensional thermal model used to determine the cell temperature of a photovoltaic (PV) module is proposed. This model that takes into account wind velocity could be helpful to better calculate the efficiency of a PV module. Two calibration methods and several experimental results are given. These measurements performed in real operating conditions were done on a single free-mounted PV module. Both of modelling approaches are presented to provide values of heat transfer coefficients that could be inserted into an external PV simulation tool.

EPE 2011 - DS3i: Topic 13: Energy Efficiency, Energy Saving Issues in System Components
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2011 ECCE Europe - Conference > EPE 2011 - Topic 13: Energy efficiency; energy saving issues in system components > EPE 2011 - DS3i: Topic 13: Energy Efficiency, Energy Saving Issues in System Components
	[return to parent folder]

	Combined Solar and AC Mains Powered Lighting System By Ulrich BOEKE, Matthias WENDT, Lennart YSEBOODT	[View] [Download]
Abstract: An experiment is presented that uses solar direct current (DC) in an AC mains powered 48 V DC power grid to reduce the AC power consumption of lighting systems in professional buildings. Measured annual AC mains power has been reduced by 15 \% for lighting systems with a combined DC solar and AC mains supply compared with a pure AC mains supplied lighting reference system.

	Efficiency improvement in DC and AC motor powered electric vehicles By Ioannis KARATZAFERIS, Lampros LAMPROPOULOS, Emmanuel TATAKIS	[View] [Download]
Abstract: Electric vehicles seem to be a solution against the greenhouse gasses emission problem. The major problem of these vehicles is low autonomy, due to the low energy density of the batteries, compared to gasoline. A way of dealing with this problem is to increase the vehicle’s efficiency, by minimizing the power losses. In this paper, ways of minimizing the power losses for DC and AC motor powered vehicles via adjusting the gear ratio and the motor’s magnetic flux are studied. To do so, the losses of all parts of the electromechanic system are calculated as a function of the gear ratio λ, and the motor's magnetic flux CΦ, with the vehicle's speed and resultant force as parameters. It can be proved that for each pair of parameters there is an optimum set (CΦ, λ) that minimizes the vehicle's losses. Finally, the theoretical analysis is verified by experimental results.

	Energy Efficient Storage Systems in the DC Link for the Drive Unit of Machine Tools By Artem KOLESNIKOV, Reimund NEUGEBAUER, Mark RICHTER	[View] [Download]
Abstract: The research of energy storage systems in the DC link of a machine tool is focused on the choice of the appropriate type of the energy storage system (passive or active) and its control strategy considering better energy efficiency. For the control strategy of the DC/DC converter two ways were taken into account: the proportional-integral and predictive control strategies. The energy consumption model of the drive group was developed in Matlab/SimPowerSystems for quantitative comparisons of the proposed energy storage systems. The model was validated by measurements of energy consumption in the drive unit of a machining centre.

	Extended-Flux Model with Core-loss Resistance of Synchronous Reluctance Motors andTorque Estimation without Core Loss Measurement and Position Encoder By Masaru HASEGAWA, Hiroki KITAHARA	[View] [Download]
Abstract: This paper proposes an extended-flux model with core-loss resistance of synchronous reluctance motors (SynRMs) and precise torque estimation without core-loss measurement and position encoder. The proposed torque estimation is useful for precise maximum torque per ampere (MTPA) control of position sensorless controlled SynRMs, which is achieved with the assistance of active and reactive powers.

	High Efficient Winding Drives with Continuous Variable Transmission (CVT) By Kenneth BENATH, Wilfried HOFMANN, Volkmar MÜLLER	[View] [Download]
Abstract: This paper shows that winding drives in combination with a continuous variable transmission (CVT) will lead to reduced rated power as well as an increased efficiency of the electrical drive. First practical experiments with imitation of a winding operation were performed to verify the theoretical investigations.

	Multilevel NPC inverter for low-voltage applications By Rudolf MECKE	[View] [Download]
Abstract: Multilevel inverter topologies are an alternative for a wide range of low voltage electrical drives. In the low voltage range (<1000 V) highly optimised switches with lower conduction and switching losses are available. For 550 V DC link voltage the power semiconductor losses of a two-level VSI with 1200 V-IGBT and a neutral-point-clamped three-level VSI in the power range between 7 to 35 kW are compared. The comparison is carried out by calculation with a linear approximation for conduction and switching losses. The calculated results are proved by simulation with the real loss curves from the manufacturers. The simulated losses are higher than the calculated especially for operation points below the rated power. Therefore, the calculation of losses which is commonly used by the power semiconductor manufacturers is not sufficient for variable loads. At 20 kHz switching frequency and an electrical power of 35 kW the semiconductor losses of the three-level inverter are 38 \% lower compared to the two-level inverter. At 7 kW electrical power the reduction of losses is even 66 \%. The further increase of the inverter levels (four- and five-level) only leads to a small improvement of the motor current quality. Moreover, suitable power semiconductors (IGBT or MOSFET) with 300 V blocking voltage are not available for five-level inverters. Therefore, four- and five level inverters cannot be included in the losses calculation within this paper. Perhaps in the near future the five-level inverter leads to a further improvement in the inverter efficiency.

	REAL TIME IMPLEMENTATION OF SUBOPTIMAL CONTROL POSITION DRIVE SYSTEM WITH INDUCTION MACHINE By Munteanu TRAIAN, Rosu EMIL, Paduraru ROMEO, Dumitriu TEODOR, Culea MIHAI	[View] [Download]
Abstract: This paper illustrates the importance of control on energy saving opportunity for electrical drives systems. The paper’s objective is to present a real time implementation of suboptimal control law for an electrical positioning system with induction machine at constant flux. The suboptimal control is based on numerical integration of the Matrix Riccati Differential Equation (MRDE).

	Smoothing Control of Wind Farm Output Fluctuation by New Scheme with Energy Storage System By Rion TAKAHASHI, Masachika NAKATANI, Junji TAMURA, Muyeen S.M., Masatoshi SUGIMASA, Akiyoshi KOMURA, Motoo FUTAMI, Masaya ICHINOSE, Kazumasa IDE	[View] [Download]
Abstract: Electrical power generation from wind power is increasing rapidly nowadays. Therefore, wind farm output power fluctuation due to wind speed variations is becoming the major concern for Transmission System Operators (TSOs) or grid companies. As a result, it is needed to connect an energy storage system (ESS) to wind farm through power converters to smoothen the wind farm output fluctuations. As power losses occur in the power converters, it is important to reduce the losses to achieve effective use of renewable energy. In this paper, a new connection scheme of ESS to wind farm is proposed in which ESS is connected to the DC bus circuit of wind generator without using a PWM based DC-DC converter. Comparative analysis of the loss characteristics between the proposed system and the conventional one in which ESS is connected to the DC bus circuit with using a PWM based DC-DC converter is presented. The proposed system can simplify overall control scheme and improve the efficiency considerably. The loss characteristics are studied by simulation analyses on the laboratory standard power system software, PSCAD/EMTDC, using the practical (measured) wind speed data.

	Thermal modelling to analyze the effect of cell temperature on PV modules energy efficiency By Florian ROMARY, Adelphe CALDEIRA, Sebastien JACQUES, Ambroise SCHELLMANNS	[View] [Download]
Abstract: In this paper, a one-dimensional thermal model used to determine the cell temperature of a photovoltaic (PV) module is proposed. This model that takes into account wind velocity could be helpful to better calculate the efficiency of a PV module. Two calibration methods and several experimental results are given. These measurements performed in real operating conditions were done on a single free-mounted PV module. Both of modelling approaches are presented to provide values of heat transfer coefficients that could be inserted into an external PV simulation tool.