EPE Association: EPE 2018 - LS5b: Power Electronics for Wind Energy

EPE 2018 - LS5b: Power Electronics for Wind Energy
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2018 ECCE Europe - Conference > EPE 2018 - Topic 05: Renewable Energy Power Systems > EPE 2018 - LS5b: Power Electronics for Wind Energy

   [return to parent folder]

   A novel bidirectional DC-DC converter for offshore DC collection grid
By Samir ALAGAB [View]
[Download]

Abstract: In this paper, a new bidirectional DC-DC converter based on the Marx principle for offshore windfarmsis presented. The proposed topology is named 'Bidirectional Modular DC-DC converter' (BMDC). Theoperating principle and the theoretical analysis of the converter under both boost and buck modes arepresented, and demonstrate that a high step-up and step-down voltage gain can be achieved with anappropriate fixed duty ratio. The two inductors of the converter are designed to resonate with thecapacitors to create resonance, forcing current zeros to enable zero current switching, and therebyreducing switching losses during both modes of operation. Simulation of a 50 MW, 6 kV/ 30 kVconverter with a switching frequency of 2kHz is explained, and the results are presented and discussed.

   AC Grid Forming by Coordinated Control of Offshore Wind Farm connected to Diode Rectifier based HVDC Link - Review and Assessment of Solutions
By Ragavendran RAMACHANDRAN [View]
[Download]

Abstract: Diode Rectifier (DR) based HVDC transmission can significantly reduce system costs and foot printof an HVDC power station for Offshore Wind Farms (OWFs), but as a consequence, the control of theoffshore AC grid becomes challenging. The replacement of the offshore Voltage Source Converter (VSC)by a passive DR leads to major research questions pertaining to the control of the offshore AC grid. Toachieve the wind farm operation and seamless power extraction, many grid forming solutions have beendevised. This paper reviews a few of the major control solutions for AC grid forming and operationof DR-HVDC based OWFs, following which a comparison is made between them. Then two of thesesolutions are selected and implemented in a study case OWF model. By using the simulation results andfurther analysis, the approaches adopted by these two solutions are elaborated further and the variouschallenges regarding the operation and control of the DR-HVDC based OWF are highlighted.

   Grid Fault Performance of Brushless Doubly-Fed Reluctance Machines in Wind Turbine Applications
By David GAY [View]
[Download]

Abstract: The DFIG and the BDFRM have very similar dynamic equations, however the BDFRM's complex flux coupling produces machine parameters very different to the DFIG. These parameter differences result in different intrinsic machine behaviour under fault conditions. This paper develops and uses a simple model to explain the fault performance differences between the machines, and then verifies these predictions using a combination of simulation and experimental results. The general conclusion is that the intrinsic large leakage inductances of the BDFRM assist with protecting the rotor side converter during grid side fault conditions.

   Wave power generation system based on magnetic lead screw
By Kai QIAO [View]
[Download]

Abstract: As a promising new transmission device, the magnetic lead screw (MLS) is trusted to have a huge potential compared to direct-drive PTO system using a linear generator for wave energy application. In this paper, the analysis and simulation of a wave power generation system utilizing a MLS are given. An important new phenomenon showing possible reduced output power for a MLS-based PTO system is illustrated and analyzed in details, which may sacrifice the benefits offered by the MLS technology when considering structural improvements only.

EPE 2018 - LS5b: Power Electronics for Wind Energy
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2018 ECCE Europe - Conference > EPE 2018 - Topic 05: Renewable Energy Power Systems > EPE 2018 - LS5b: Power Electronics for Wind Energy
	[return to parent folder]

	A novel bidirectional DC-DC converter for offshore DC collection grid By Samir ALAGAB	[View] [Download]
Abstract: In this paper, a new bidirectional DC-DC converter based on the Marx principle for offshore windfarmsis presented. The proposed topology is named 'Bidirectional Modular DC-DC converter' (BMDC). Theoperating principle and the theoretical analysis of the converter under both boost and buck modes arepresented, and demonstrate that a high step-up and step-down voltage gain can be achieved with anappropriate fixed duty ratio. The two inductors of the converter are designed to resonate with thecapacitors to create resonance, forcing current zeros to enable zero current switching, and therebyreducing switching losses during both modes of operation. Simulation of a 50 MW, 6 kV/ 30 kVconverter with a switching frequency of 2kHz is explained, and the results are presented and discussed.

	AC Grid Forming by Coordinated Control of Offshore Wind Farm connected to Diode Rectifier based HVDC Link - Review and Assessment of Solutions By Ragavendran RAMACHANDRAN	[View] [Download]
Abstract: Diode Rectifier (DR) based HVDC transmission can significantly reduce system costs and foot printof an HVDC power station for Offshore Wind Farms (OWFs), but as a consequence, the control of theoffshore AC grid becomes challenging. The replacement of the offshore Voltage Source Converter (VSC)by a passive DR leads to major research questions pertaining to the control of the offshore AC grid. Toachieve the wind farm operation and seamless power extraction, many grid forming solutions have beendevised. This paper reviews a few of the major control solutions for AC grid forming and operationof DR-HVDC based OWFs, following which a comparison is made between them. Then two of thesesolutions are selected and implemented in a study case OWF model. By using the simulation results andfurther analysis, the approaches adopted by these two solutions are elaborated further and the variouschallenges regarding the operation and control of the DR-HVDC based OWF are highlighted.

	Grid Fault Performance of Brushless Doubly-Fed Reluctance Machines in Wind Turbine Applications By David GAY	[View] [Download]
Abstract: The DFIG and the BDFRM have very similar dynamic equations, however the BDFRM's complex flux coupling produces machine parameters very different to the DFIG. These parameter differences result in different intrinsic machine behaviour under fault conditions. This paper develops and uses a simple model to explain the fault performance differences between the machines, and then verifies these predictions using a combination of simulation and experimental results. The general conclusion is that the intrinsic large leakage inductances of the BDFRM assist with protecting the rotor side converter during grid side fault conditions.

	Wave power generation system based on magnetic lead screw By Kai QIAO	[View] [Download]
Abstract: As a promising new transmission device, the magnetic lead screw (MLS) is trusted to have a huge potential compared to direct-drive PTO system using a linear generator for wave energy application. In this paper, the analysis and simulation of a wave power generation system utilizing a MLS are given. An important new phenomenon showing possible reduced output power for a MLS-based PTO system is illustrated and analyzed in details, which may sacrifice the benefits offered by the MLS technology when considering structural improvements only.