http://hdl.handle.net/2117/3669 Mon, 20 May 2013 17:53:11 GMT 2013-05-20T17:53:11Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/16766 Title: Control method for wireless inductive energy transfer systems with relatively large air gap Authors: Van Der Pijl, Frank F. A; Bauer, Pavol T.; Castilla Fernández, Miguel Abstract: Recent improvements in semiconductor technology make efficient switching possible at higher frequencies, which benefits the application of wireless inductive energy transfer. However, a higher frequency does not alter the magnetic coupling between energy transmitter and receiver. Due to the still weak magnetic coupling between transmitting and receiving sides that are separated by a substantial air gap, energy circulates in the primary transmitting side without being transferred to the secondary receiving side. This paper introduces an energy control method that reduces energy circulation in the primary to zero. Themethod makes use of the fact that energy can be stored in a magnetic field by the primary side and absorbed by the secondary side. Furthermore, the secondary side converter topology is modified in order to boost the damping as seen by the primary converter at required times. Essentially, the control method realizes an energetic coupling factor of one between the air coils of the wireless transformer. The working principle of the controlmethod has been verified with an experimental setup. Mon, 22 Oct 2012 07:34:21 GMT http://hdl.handle.net/2117/16766 2012-10-22T07:34:21Z Van Der Pijl, Frank F. A; Bauer, Pavol T.; Castilla Fernández, Miguel no Air gap, energy transfer, inductive coupling, power transfer, wireless Recent improvements in semiconductor technology make efficient switching possible at higher frequencies, which benefits the application of wireless inductive energy transfer. However, a higher frequency does not alter the magnetic coupling between energy transmitter and receiver. Due to the still weak magnetic coupling between transmitting and receiving sides that are separated by a substantial air gap, energy circulates in the primary transmitting side without being transferred to the secondary receiving side. This paper introduces an energy control method that reduces energy circulation in the primary to zero. Themethod makes use of the fact that energy can be stored in a magnetic field by the primary side and absorbed by the secondary side. Furthermore, the secondary side converter topology is modified in order to boost the damping as seen by the primary converter at required times. Essentially, the control method realizes an energetic coupling factor of one between the air coils of the wireless transformer. The working principle of the controlmethod has been verified with an experimental setup. http://hdl.handle.net/2117/16764 Title: Adaptive sliding-mode control for a multiple-user inductive power transfer system without need for communication Authors: Van Der Pijl, Frank F. A; Castilla Fernández, Miguel; Bauer, Pavol T. Abstract: A complicating aspect in the control design of resonant inductive power transfer systems is the absence of a direct communication link between primary and (multiple) secondary system sides. This paper introduces a new adaptive sliding-mode control surface, which continuously adapts the inductive system’s input power to the required, but unknown, variable load power. As a result, an indirect communication link is redundant. Furthermore, due to matching input and output power, optimum relative system efficiency is automatically guaranteed in the entire system’s output power range. The controller design, which has a simple analog implementation, has been verified with a dual-load experimental contactless system. Fri, 19 Oct 2012 12:09:56 GMT http://hdl.handle.net/2117/16764 2012-10-19T12:09:56Z Van Der Pijl, Frank F. A; Castilla Fernández, Miguel; Bauer, Pavol T. no Inductive power transfer (IPT), multiple output, quantum modulation, sliding-mode control A complicating aspect in the control design of resonant inductive power transfer systems is the absence of a direct communication link between primary and (multiple) secondary system sides. This paper introduces a new adaptive sliding-mode control surface, which continuously adapts the inductive system’s input power to the required, but unknown, variable load power. As a result, an indirect communication link is redundant. Furthermore, due to matching input and output power, optimum relative system efficiency is automatically guaranteed in the entire system’s output power range. The controller design, which has a simple analog implementation, has been verified with a dual-load experimental contactless system. http://hdl.handle.net/2117/16728 Title: Investigation of nanoscale interactions by means of subharmonic excitation Authors: Santos, Sergio; Phillips, M.A.; Verdaguer, Albert; Font Teixidó, Josep; Chiesa, Matteo; Gadelrab,, K.; Stefancich, M.; Armstrong, P.; Li, G.; Souier, T.; Thomson, Neil H.; Barcons Xixons, Víctor Abstract: Multifrequency atomic force microscopy holds promise as a method to provide qualitative and quantitative information about samples with high spatial resolution. Here, we provide experimental evidence of the excitation of subharmonics in ambient conditions in the regions where capillary interactions are predicted to be the mechanism of excitation. We also experimentally decouple a second mechanism for subharmonic excitation that is highly independent of environmental conditions such as relative humidity. This implies that material properties could be mapped. Subharmonic excitation could lead to experimental determination of surface water affinity in the nanoscale whenever water interactions are the mechanism of excitation. Tue, 16 Oct 2012 10:01:28 GMT http://hdl.handle.net/2117/16728 2012-10-16T10:01:28Z Santos, Sergio; Phillips, M.A.; Verdaguer, Albert; Font Teixidó, Josep; Chiesa, Matteo; Gadelrab,, K.; Stefancich, M.; Armstrong, P.; Li, G.; Souier, T.; Thomson, Neil H.; Barcons Xixons, Víctor no Ambient conditions, Capillary interactions, Environmental conditions, Experimental determination, Experimental evidence, High spatial resolution, Material property, Multi frequency, Nano scale, Nanoscale interactions, Quantitative information, Sub-harmonic excitation, Subharmonics, Water affinity, Water interactions Multifrequency atomic force microscopy holds promise as a method to provide qualitative and quantitative information about samples with high spatial resolution. Here, we provide experimental evidence of the excitation of subharmonics in ambient conditions in the regions where capillary interactions are predicted to be the mechanism of excitation. We also experimentally decouple a second mechanism for subharmonic excitation that is highly independent of environmental conditions such as relative humidity. This implies that material properties could be mapped. Subharmonic excitation could lead to experimental determination of surface water affinity in the nanoscale whenever water interactions are the mechanism of excitation. http://hdl.handle.net/2117/16725 Title: Quantification of dissipation and deformation in ambient atomic force microscopy Authors: Santos, Sergio; Gadelrab,, K.; Barcons Xixons, Víctor; Stefancich, M.; Chiesa, Matteo Abstract: A formalism to extract and quantify unknown quantities such as sample deformation, the viscosity of the sample and surface energy hysteresis in amplitude modulation atomic force microscopy is presented. Recovering the unknowns only requires the cantilever to be accurately calibrated and the dissipative processes occurring during sample deformation to be well modeled. The theory is validated by comparison with numerical simulations and shown to be able to provide, in principle, values of sample deformation with picometer resolution. Tue, 16 Oct 2012 08:18:07 GMT http://hdl.handle.net/2117/16725 2012-10-16T08:18:07Z Santos, Sergio; Gadelrab,, K.; Barcons Xixons, Víctor; Stefancich, M.; Chiesa, Matteo no Dissipative process, Energy hysteresis, Picometer resolution, Sample deformation, Unknown quantity A formalism to extract and quantify unknown quantities such as sample deformation, the viscosity of the sample and surface energy hysteresis in amplitude modulation atomic force microscopy is presented. Recovering the unknowns only requires the cantilever to be accurately calibrated and the dissipative processes occurring during sample deformation to be well modeled. The theory is validated by comparison with numerical simulations and shown to be able to provide, in principle, values of sample deformation with picometer resolution. http://hdl.handle.net/2117/16413 Title: Control scheme for photovoltaic three-phase inverters to minimize peak currents during unbalanced grid-voltage sags Authors: Miret Tomàs, Jaume; Castilla Fernández, Miguel; Camacho Santiago, Antonio; García de Vicuña Muñoz de la Nava, José Luis; Matas Alcalá, José Abstract: Nowadays, the majority of the photovoltaic (PV) power sources are connected to the public grid. One of the main connection problems occurs when voltage sags appear in the grid due to short circuits, lightning, etc. International standards regulate the grid connection of PV systems, forcing the source to remain connected during short-time grid-voltage faults. As a consequence, during the voltage sag, the source should operate with increasing converter currents to maintain the injection of the generated power. This abnormal operation may result in nondesired system disconnections due to overcurrents. This paper proposes a controller for a PV three-phase inverter that ensuresminimum peak values in the grid-injected currents, as compared with conventional controllers. From the system analysis, a design method is presented in order to set the parameters of the control scheme. Selected experimental results are reported in order to validate the effectiveness of the proposed control. Mon, 03 Sep 2012 07:21:25 GMT http://hdl.handle.net/2117/16413 2012-09-03T07:21:25Z Miret Tomàs, Jaume; Castilla Fernández, Miguel; Camacho Santiago, Antonio; García de Vicuña Muñoz de la Nava, José Luis; Matas Alcalá, José no Fault ride-through, grid international standards, photovoltaic (PV) power source, voltage sag Nowadays, the majority of the photovoltaic (PV) power sources are connected to the public grid. One of the main connection problems occurs when voltage sags appear in the grid due to short circuits, lightning, etc. International standards regulate the grid connection of PV systems, forcing the source to remain connected during short-time grid-voltage faults. As a consequence, during the voltage sag, the source should operate with increasing converter currents to maintain the injection of the generated power. This abnormal operation may result in nondesired system disconnections due to overcurrents. This paper proposes a controller for a PV three-phase inverter that ensuresminimum peak values in the grid-injected currents, as compared with conventional controllers. From the system analysis, a design method is presented in order to set the parameters of the control scheme. Selected experimental results are reported in order to validate the effectiveness of the proposed control. http://hdl.handle.net/2117/15767 Title: Spatial horizons in amplitude and frequency modulation atomic force microscopy Authors: Font Teixidó, Josep; Santos Hernandez, Sergi; Barcons Xixons, Víctor; Thomson, Neil H.; Verdaguer, Albert; Chiesa, Matteo Abstract: In dynamic atomic force microscopy (AFM) the cantilever is vibrated and its dynamics are monitored to probe the sample with nanoscale and atomic resolution. Amplitude and frequency modulation (AM and FM) atomic force microscopy have established themselves as the most powerful, robust and reliable techniques in the field. Nevertheless, it is still debatable whether one or the other technique is preferred in a given medium or experiment. Here, we quantitatively establish the limitations in resolution of one and the other technique by introducing the concept of space horizon SH and quantifying it. The SH is the limiting space boundary beyond which collective atomic interactions do not affect the detection parameters of a given feedback system. We show that while an FM feedback can resolve an atom where an AM feedback might fail, relative contrast is in fact equivalent for both feedback systems. That is, if the AM feedback could detect sufficiently small amplitude shifts and there was no noise, single atom imaging would be equivalent in AM and FM. Fri, 27 Apr 2012 15:40:55 GMT http://hdl.handle.net/2117/15767 2012-04-27T15:40:55Z Font Teixidó, Josep; Santos Hernandez, Sergi; Barcons Xixons, Víctor; Thomson, Neil H.; Verdaguer, Albert; Chiesa, Matteo no In dynamic atomic force microscopy (AFM) the cantilever is vibrated and its dynamics are monitored to probe the sample with nanoscale and atomic resolution. Amplitude and frequency modulation (AM and FM) atomic force microscopy have established themselves as the most powerful, robust and reliable techniques in the field. Nevertheless, it is still debatable whether one or the other technique is preferred in a given medium or experiment. Here, we quantitatively establish the limitations in resolution of one and the other technique by introducing the concept of space horizon SH and quantifying it. The SH is the limiting space boundary beyond which collective atomic interactions do not affect the detection parameters of a given feedback system. We show that while an FM feedback can resolve an atom where an AM feedback might fail, relative contrast is in fact equivalent for both feedback systems. That is, if the AM feedback could detect sufficiently small amplitude shifts and there was no noise, single atom imaging would be equivalent in AM and FM. http://hdl.handle.net/2117/15659 Title: Simple low-cost hysteretic controller for multiphase synchronous buck converters Authors: Borrell, Angel; Castilla Fernández, Miguel; Miret Tomàs, Jaume; Matas Alcalá, José; García de Vicuña Muñoz de la Nava, José Luis Abstract: This paper presents a novel hysteretic controller for a multiphase synchronous buck converter supplying low voltage, high current, and high slew-rate loads. The control scheme implements the main control functions for powering such demanding loads, including output-voltage regulation, adaptive voltage positioning, current sharing, and phase interleaving. This paper also describes a control-design methodology based on outputimpedance analysis. This design leads to optimal output-voltage transient response with a simple and low-cost control implementation. Simulation and experimental results are reported in order to validate the features of the novel control scheme. Mon, 26 Mar 2012 08:56:57 GMT http://hdl.handle.net/2117/15659 2012-03-26T08:56:57Z Borrell, Angel; Castilla Fernández, Miguel; Miret Tomàs, Jaume; Matas Alcalá, José; García de Vicuña Muñoz de la Nava, José Luis no This paper presents a novel hysteretic controller for a multiphase synchronous buck converter supplying low voltage, high current, and high slew-rate loads. The control scheme implements the main control functions for powering such demanding loads, including output-voltage regulation, adaptive voltage positioning, current sharing, and phase interleaving. This paper also describes a control-design methodology based on outputimpedance analysis. This design leads to optimal output-voltage transient response with a simple and low-cost control implementation. Simulation and experimental results are reported in order to validate the features of the novel control scheme. http://hdl.handle.net/2117/14313 Title: Design of an embedded control system laboratory experiment Authors: Martí Colom, Pau; Velasco García, Manel; Fuertes Armengol, José Mª; Camacho Santiago, Antonio; Buttazzo, Giorgio Abstract: This paper presents a prototype laboratory experiment to be integrated in the education of embedded control system engineers. The experiment, a real-time control of a dynamical system, is designed to drive students to a deeper understanding and integration of the diverse theoretical concepts that often come from different disciplines such as real-time systems and control systems. Rather than proposing the experiment for a particular course within an embedded system engineering curriculum, this paper describes how the experiment can be tailored to the needs and diverse background of both undergraduate and graduate students education. Thu, 22 Dec 2011 13:08:12 GMT http://hdl.handle.net/2117/14313 2011-12-22T13:08:12Z Martí Colom, Pau; Velasco García, Manel; Fuertes Armengol, José Mª; Camacho Santiago, Antonio; Buttazzo, Giorgio no This paper presents a prototype laboratory experiment to be integrated in the education of embedded control system engineers. The experiment, a real-time control of a dynamical system, is designed to drive students to a deeper understanding and integration of the diverse theoretical concepts that often come from different disciplines such as real-time systems and control systems. Rather than proposing the experiment for a particular course within an embedded system engineering curriculum, this paper describes how the experiment can be tailored to the needs and diverse background of both undergraduate and graduate students education. http://hdl.handle.net/2117/13457 Title: The intrinsic resolution limit in the atomic force microscope: implications for heights of nano-scale features Authors: Santos, Sergio; Barcons Xixons, Víctor; Christenson, Hugo K.; Font Teixidó, Josep; Thomson, Neil H. Fri, 07 Oct 2011 12:48:33 GMT http://hdl.handle.net/2117/13457 2011-10-07T12:48:33Z Santos, Sergio; Barcons Xixons, Víctor; Christenson, Hugo K.; Font Teixidó, Josep; Thomson, Neil H. no http://hdl.handle.net/2117/13219 Title: How localized are energy dissipation processes in nanoscale interactions? Authors: Santos, Sergio; Barcons Xixons, Víctor; Verdaguer, Albert; Font Teixidó, Josep; Thomson, Neil H.; Chiesa, Mateo Abstract: We describe fundamental energy dissipation in dynamic nanoscale processes in terms of the localization of the interactions. In this respect, the areal density of the energy dissipated and the effective area of interaction in which each process occurs are calculated for four elementary dissipative processes. It is the ratio between these two, which we term M that provides information about how localized the interactions are. We show that neither the phase lag, nor the magnitude of the energy dissipated alone provide information about energy localization but M has to be considered instead. Fri, 16 Sep 2011 13:21:54 GMT http://hdl.handle.net/2117/13219 2011-09-16T13:21:54Z Santos, Sergio; Barcons Xixons, Víctor; Verdaguer, Albert; Font Teixidó, Josep; Thomson, Neil H.; Chiesa, Mateo no We describe fundamental energy dissipation in dynamic nanoscale processes in terms of the localization of the interactions. In this respect, the areal density of the energy dissipated and the effective area of interaction in which each process occurs are calculated for four elementary dissipative processes. It is the ratio between these two, which we term M that provides information about how localized the interactions are. We show that neither the phase lag, nor the magnitude of the energy dissipated alone provide information about energy localization but M has to be considered instead. http://hdl.handle.net/2117/11564 Title: Design and analysis of the droop control method for parallel inverters considering the impact of the complex impedance on the power sharing Authors: Yao, W.; Chen, Min; Matas Alcalá, José; Guerrero Zapata, Josep Maria; Qian, Z.-M. Abstract: This paper investigates the characteristics of the active and reactive power sharing in a parallel inverters system under different system impedance conditions. The analyses conclude that the conventional droop method cannot achieve efficient power sharing for the case of a system with complex impedance condition. To achieve the proper power balance and minimize the circulating current in the different impedance situations, a novel droop controller that considers the impact of complex impedance is proposed in this paper. This controller can simplify the coupled active and reactive power relationships, which are caused by the complex impedance in the parallel system. In addition, a virtual complex impedance loop is included in the proposed controller to minimize the fundamental and harmonic circulating current that flows in the parallel system. Compared to the other methods, the proposed controller can achieve accurate power sharing, offers efficient dynamic performance, and is more adaptive to different line impedance situations. Simulation and experimental results are presented to prove the validity and the improvements achieved by the proposed controller. Mon, 28 Feb 2011 11:09:34 GMT http://hdl.handle.net/2117/11564 2011-02-28T11:09:34Z Yao, W.; Chen, Min; Matas Alcalá, José; Guerrero Zapata, Josep Maria; Qian, Z.-M. no This paper investigates the characteristics of the active and reactive power sharing in a parallel inverters system under different system impedance conditions. The analyses conclude that the conventional droop method cannot achieve efficient power sharing for the case of a system with complex impedance condition. To achieve the proper power balance and minimize the circulating current in the different impedance situations, a novel droop controller that considers the impact of complex impedance is proposed in this paper. This controller can simplify the coupled active and reactive power relationships, which are caused by the complex impedance in the parallel system. In addition, a virtual complex impedance loop is included in the proposed controller to minimize the fundamental and harmonic circulating current that flows in the parallel system. Compared to the other methods, the proposed controller can achieve accurate power sharing, offers efficient dynamic performance, and is more adaptive to different line impedance situations. Simulation and experimental results are presented to prove the validity and the improvements achieved by the proposed controller. http://hdl.handle.net/2117/11555 Title: Grid-fault control scheme for three-phase photovoltaic inverters with adjustable power quality characteristics Authors: Castilla Fernández, Miguel; Miret Tomàs, Jaume; Sosa Avendaño, Jorge Luis; Matas Alcalá, José; García de Vicuña Muñoz de la Nava, José Luis Abstract: The power quality of a three-phase photovoltaic (PV) inverter drastically deteriorates in the presence of grid faults with unbalanced voltages.Aripple in the injected power and an increase in the current harmonic distortion are the main noticeable adverse effects produced by this abnormal grid situation. Several grid-fault control schemes are nowadays available for operating under unbalanced grid voltage. These control schemes usually have extreme power quality characteristics. Some of them have been conceived to completely avoid power ripple during unbalanced voltage sags, but at an expense of high current harmonic distortion.With other schemes, the harmonic distortion is totally eliminated but at an expense of high ripple in the injected power. This paper further explores the performance of PV inverters under unbalanced voltage sags. It has three theoretical contributions: 1) a generalized control scheme, which includes the aforementioned grid-fault controllers as particular cases; 2) a control strategy based on the use of continuous values for the control parameters. This original approach gives adjustable power quality characteristics that cannot be achieved with the previous control schemes; 3) three different control algorithms for calculating the continuous values of the control parameters. These contributions are experimentally validated with a digital signal processor-based laboratory prototype. Mon, 28 Feb 2011 08:59:37 GMT http://hdl.handle.net/2117/11555 2011-02-28T08:59:37Z Castilla Fernández, Miguel; Miret Tomàs, Jaume; Sosa Avendaño, Jorge Luis; Matas Alcalá, José; García de Vicuña Muñoz de la Nava, José Luis no The power quality of a three-phase photovoltaic (PV) inverter drastically deteriorates in the presence of grid faults with unbalanced voltages.Aripple in the injected power and an increase in the current harmonic distortion are the main noticeable adverse effects produced by this abnormal grid situation. Several grid-fault control schemes are nowadays available for operating under unbalanced grid voltage. These control schemes usually have extreme power quality characteristics. Some of them have been conceived to completely avoid power ripple during unbalanced voltage sags, but at an expense of high current harmonic distortion.With other schemes, the harmonic distortion is totally eliminated but at an expense of high ripple in the injected power. This paper further explores the performance of PV inverters under unbalanced voltage sags. It has three theoretical contributions: 1) a generalized control scheme, which includes the aforementioned grid-fault controllers as particular cases; 2) a control strategy based on the use of continuous values for the control parameters. This original approach gives adjustable power quality characteristics that cannot be achieved with the previous control schemes; 3) three different control algorithms for calculating the continuous values of the control parameters. These contributions are experimentally validated with a digital signal processor-based laboratory prototype. http://hdl.handle.net/2117/11513 Title: Guest Editorial Authors: Teodorescu, Remus; Sauter, Thilo; Rodríguez Cortés, Pedro; Rodriguez, José; Palensky, Peter; Nasiri, Adel; Kupzog, Friederich; Liserre, M.; Balcells Sendra, Josep; Basso, Thomas; Bialasiewicz, Jan T.; Cecati, Carlo; Chakraborty, Sudipta; Guerrero Zapata, Josep Maria; Kazerani, Mehrdad Thu, 24 Feb 2011 07:29:50 GMT http://hdl.handle.net/2117/11513 2011-02-24T07:29:50Z Teodorescu, Remus; Sauter, Thilo; Rodríguez Cortés, Pedro; Rodriguez, José; Palensky, Peter; Nasiri, Adel; Kupzog, Friederich; Liserre, M.; Balcells Sendra, Josep; Basso, Thomas; Bialasiewicz, Jan T.; Cecati, Carlo; Chakraborty, Sudipta; Guerrero Zapata, Josep Maria; Kazerani, Mehrdad no http://hdl.handle.net/2117/8278 Title: Selective harmonic-compensation control for single-phase active power filter with high harmonic rejection Authors: Miret Tomàs, Jaume; Castilla Fernández, Miguel; Matas Alcalá, José; Guerrero Zapata, Josep Maria; Vásquez Quintero, Juan Carlos Abstract: This paper presents a linear current control scheme for single-phase active power filters. The approach is based on an outer voltage loop, an inner current loop, and a resonant selective harmonic compensator. The design of the control parameters is carried out using conventional linear techniques (analysis of loop gain and other disturbance-rejection transfer functions). The performance of the proposed controller is evaluated and compared with two reference controllers: a basic control and an advanced repetitive control. In comparison with these controllers, the proposed control scheme provides additional attenuation to the harmonics coming from the load current, the grid voltage, and the reference signal, resulting in a grid current with lower harmonic distortion. Experimental results are reported in order to validate this paper. Description: (c) 2009 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Tue, 20 Jul 2010 11:24:59 GMT http://hdl.handle.net/2117/8278 2010-07-20T11:24:59Z Miret Tomàs, Jaume; Castilla Fernández, Miguel; Matas Alcalá, José; Guerrero Zapata, Josep Maria; Vásquez Quintero, Juan Carlos no This paper presents a linear current control scheme for single-phase active power filters. The approach is based on an outer voltage loop, an inner current loop, and a resonant selective harmonic compensator. The design of the control parameters is carried out using conventional linear techniques (analysis of loop gain and other disturbance-rejection transfer functions). The performance of the proposed controller is evaluated and compared with two reference controllers: a basic control and an advanced repetitive control. In comparison with these controllers, the proposed control scheme provides additional attenuation to the harmonics coming from the load current, the grid voltage, and the reference signal, resulting in a grid current with lower harmonic distortion. Experimental results are reported in order to validate this paper. http://hdl.handle.net/2117/7477 Title: Design of an analog quasi-steady-state nonlinear current-mode controller for single-phase active power filter Authors: Miret Tomàs, Jaume; García de Vicuña Muñoz de la Nava, José Luis; Castilla Fernández, Miguel; Matas Alcalá, José; Guerrero Zapata, Josep Maria Abstract: The injection of sinusoidal current to an electrical grid is nowadays possible with the use of active power filters (APFs).With quasi-steady-state (QSS) nonlinear controllers, these power filters provide low grid-current-harmonic content with simple-control analog implementation. This paper focuses on the design of a QSS nonlinear controller for a single-phase APF. A complete analysis based on the sliding-mode-control theory is given. From the analysis, a set of control-design guidelines is presented to select the gains and parameters of the control scheme. Selected experimental results are reported to validate the theoretical design procedure. Wed, 02 Jun 2010 07:48:21 GMT http://hdl.handle.net/2117/7477 2010-06-02T07:48:21Z Miret Tomàs, Jaume; García de Vicuña Muñoz de la Nava, José Luis; Castilla Fernández, Miguel; Matas Alcalá, José; Guerrero Zapata, Josep Maria no The injection of sinusoidal current to an electrical grid is nowadays possible with the use of active power filters (APFs).With quasi-steady-state (QSS) nonlinear controllers, these power filters provide low grid-current-harmonic content with simple-control analog implementation. This paper focuses on the design of a QSS nonlinear controller for a single-phase APF. A complete analysis based on the sliding-mode-control theory is given. From the analysis, a set of control-design guidelines is presented to select the gains and parameters of the control scheme. Selected experimental results are reported to validate the theoretical design procedure.