Josep Bordonau

• Doctor of Engineering in 1990
• Professor (Associate) at Universitat Politècnica de Catalunya - BarcelonaTech, Barcelona, Spain

The battery is at the heart of the electric vehicle and determines many of its key performance features. Therefore, an optimized design of the battery is critical. On one hand, the design of batteries based on a single battery cell leads in many cases to oversized batteries in terms of energy or power, due to the diversity of requirements of the di...

p>The battery is at the heart of the electric vehicle and determines many of its key performance features. Hybrid batteries, combining two battery cell chemistries, benefit from the particular strengths of each battery cell technology, such as high specific energy or high specific power. This paper proposes a novel hybrid battery configuration wher...

p>The battery is at the heart of the electric vehicle and determines many of its key performance features. Hybrid batteries, combining two battery cell chemistries, benefit from the particular strengths of each battery cell technology, such as high specific energy or high specific power. This paper proposes a novel hybrid battery configuration wher...

Nowadays, the internal combustion engine in vehicles is being replaced by electric motors, giving way to the electric vehicle, which results in reduced environmental impact, higher efficiency and lower emission of greenhouse gases. The powertrain of an electric vehicle is its most prominent subsystem, with the batteries and traction inverter being...

This article proposes a novel device designated as an intelligent electronic fuse (iFuse) intended to be connected in series with any current-bidirectional voltage-unidirectional active switch present in a power converter. The iFuse duty is to selectively isolate its series-associated switch from the rest of the converter circuit immediately after...

Neutral-point-clamped multilevel converters are currently a suitable solution for a wide range of applications. It is well known that the capacitor voltage balance is a major issue for this topology. In this paper, a brief summary of the basic topologies, modulations, and features of neutral-point-clamped multilevel converters is presented, prior t...

The present paper proposes a novel device defined as an intelligent electronic fuse (iFuse) meant to be connected in series with any current-bidirectional voltage-unidirectional active switch present in a given converter. The iFuse duty is to isolate its series-associated switch from the rest of the converter circuit immediately after detecting tha...

The present paper proposes a novel device defined as an intelligent electronic fuse (iFuse) meant to be connected in series with any current-bidirectional voltage-unidirectional active switch present in a given converter. The iFuse duty is to isolate its series- associated switch from the rest of the converter circuit immediately after detecting th...

The present paper provides a solution to operate multilevel dual-active-bridge (ML-DAB) converters built upon neutral-point-clamped switching legs in a full-bridge disposition and with any number of levels on either side of the converter. The main issue of such converters is addressing the inherent unbalance of the dc-link capacitor voltages, which...

This paper proposes a closed-loop control implementation fully-embedded into an FPGA for a permanent-magnet synchronous motor (PMSM) drive based on a four-level active-clamped converter. The proposed FPGA controller comprises a field-oriented control to drive the PMSM, a DC-link voltage balancing closed-loop control (VBC), and a virtual-vector-base...

The future of energy largely depends on the creativity and innovation capacity of energy engineers. Projects on renewable energy developed by master’s students can be significant to know the vision of the new generation of energy engineers. The projects of 168 international students pursuing EIT KIC InnoEnergy masters, more specifically MSc RENE an...

As wind power technology points to increase power ratings, the implementation based on a permanent-magnet synchronous generator with a full power converter is expanding its market share. Multilevel converters, as for example, neutral-point clamped converters, are therefore well suited for this application. Predictive current control presents simila...

Aiming to improve the performance features ofconventional two-level dual-active-bridge (DAB) converters, thispaper presents a three-level neutral-point-clamped (NPC) DABdc-dc converter. A general modulation pattern is initially defined,the dc-link capacitor voltage balancing is analyzed in detail,and a proper balancing control is designed. Then, a...

This paper presents an efficiency comparison between silicon-carbide technology and silicon technology. In order to achieve this, the efficiency of an active neutral-point clamped converter built up with silicon carbide power-devices is compared with the efficiency of an active neutral-point clamped converter built up with silicon power-devices, un...

This paper presents a capacitor voltage balancing control applicable to any multilevel dc–ac converter formed by a single set of series-connected capacitors implementing the dc link and semiconductor devices, such as the diode-clamped topology. The control is defined for any number of dc-link voltage levels and converter legs (for single-phase and...

The low voltage ride-through requirement demands the wind power plants to remain connected to the grid in presence of grid voltage dips, helping actively the network overall control to keep network voltage and frequency stable. Wind power technology points to increase power ratings. Hence, multilevel converters, as for example, neutral-point clampe...

This paper studies the coupling between the capacitor voltage control loops of diode-clamped (or functionally equivalent) multilevel multileg (multiphase) dc-ac converters. From a complete model of the plant revealing the coupling, a simple approach consisting in multiplying the vector of control commands by a constant matrix is proposed to decoupl...

Predictive current control is applied to a wind energy conversion system implemented with a permanent-magnet synchronous generator connected to the grid through a back-to-back neutral-point-clamped converter. This control approach allows to work in steady-state and to fulfill the low-voltage ride through requirements demanded by the power system op...

This paper presents an efficiency analysis of a recently-published topology, the multilevel-active-clamped (MAC) topology. In order to assess the MAC topology, an efficiency comparison between a four-level MAC leg and a conventional two-level leg operating in low voltage is carried out. First, overall losses of both topologies are estimated. Then,...

Thanks to the inherent redundancy to generate the different output voltage levels, the multilevel active-clamped (MAC) topology presents an important fault-tolerance ability which makes it interesting for several applications. This paper presents an analysis of the fault-tolerance capacity of the MAC converter. Both open-circuit and short-circuit f...

This paper presents a converter consisting of a dual active bridge built upon three-level neutral-point-clamped legs in order to synthesize a five-level medium- or high- frequency stepped waveform on each side of the transformer. Thanks to the modulation extra degrees of freedom, the transformer current harmonic content can be reduced (less magneti...

In the previous literature, the introduction of the virtual space vector concept for the three-level three-leg neutral-point-clamped converter has led to the definition of pulsewidth modulation (PWM) strategies guaranteeing the dc-link capacitor voltage balance under any type of load, with the only requirement being that the addition of the three p...

This paper studies several design issues of the multilevel active-clamped (MAC) topology. Several guidelines are proposed to guarantee a proper MAC converter design and improve its performance. The inclusion of a resistor network to balance the blocking voltage of devices when the converter is in OFF state, the use of self-powered gate-driver power...

A novel noninverting boost-buck dc-dc converter topology is presented, applicable when both sides of the converter need to have the same grounding. It is based on the back-to-back connection of two n-level active-clamped or diode-clamped converter legs, and allows bidirectional power flow. A simplified topology is proposed for unidirectional power...

Thanks to the inherent redundancy to generate the different output voltage levels, the multilevel active clamped (MAC) topology presents an important fault-tolerance ability which makes it interesting for several applications. This paper presents an analysis of the fault-tolerance capacity of the MAC converter. Both open-circuit and short-circuit f...

The increasing influence of wind power in the power system operation has caused the power system operators to include wind power plants in the control of the overall power system, both in steady-state and transient operation. Therefore, the grid connection requirements of the power system operators involve wind power systems. Low voltage ride-throu...

This letter proposes a new control scheme for the neutral-point (NP) balance in single-phase three-level NP-clamped converters. The control is addressed considering the plant under study, a nonlinear time-variant system. A quasi-exact linearization is applied allowing the application of classic control techniques. The described method is simple, ge...

In presence of grid voltage dips, Low Voltage Ride-Through (LVRT) requirements demand the wind power plant to remain connected to the grid, helping the network to keep voltage and frequency stable. Neutral-point-clamped (NPC) converters are appropriate for wind power systems, because the current trend of increasing voltage levels. Predictive curren...

A novel noninverting boost-buck dc-dc converter topology is presented, applicable when both sides of the converter need to have the same grounding. It is based on the back-to-back connection of two n-level diode-clamped converter legs, and allows bidirectional power flow. A simplified topology is proposed for unidirectional power flow applications....

This paper presents a three-level three-phase neutral-point-clamped back-to-back converter applied to a wind emulator, where a wind power generator is connected to the grid through the back-to-back converter. The converter regulates the power extracted from the generator and controls how this power is injected to the grid with the desired power fac...

This paper presents a new Power Electronic Building Block (PEBB) designed to facilitate the implementation of different power converter topologies. The proposed PEBB consists of two diodes and two transistors and it can be used to implement the most relevant power converter topologies, due to its modularity. The addition of the two diodes is an exc...

This paper presents the definition of the virtual vectors for the general case of an n -level two-leg diode-clamped converter, suggests guidelines for designing virtual-vector pulsewidth modulation (PWM) strategies, and provides the mathematical expressions of the leg duty-ratio waveforms corresponding to this family of PWMs. Modulations defined up...

Low-voltage ride-through (LVRT) requirements demand wind-power plants to remain connected to the network in presence of grid-voltage dips. Most dips present positive-, negative-, and zero-sequence components. Hence, regulators based on symmetrical components are well suited to control grid-connected converters. A neutral-point-clamped topology has...

In the above titled paper (ibid., vol. 23, no. 4, pp. 1751-1758, Jul 08), some equations were printed incorrectly. The corrected equations are presented here.

In the previous literature, the introduction of the virtual-space-vector (VV) concept for the three-level, three-leg neutral-point-clamped converter has led to the definition of pulsewidth modulation (PWM) strategies, guaranteeing a dc-link capacitor voltage balance in every switching cycle under any type of load, with the only requirement being th...

In photovoltaic (PV) power systems where a set of series-connected PV arrays (PVAs) is connected to a conventional two-level inverter, the occurrence of partial shades and/or the mismatching of PVAs leads to a reduction of the power generated from its potential maximum. To overcome these problems, the connection of the PVAs to a multilevel diode-cl...

In the previous literature, it has been reported that it is not possible to guarantee the balance of the DC-link capacitor voltages of multilevel three-phase diode-clamped DC-AC converters with passive front-ends for high modulation indices, especially for more than three levels. This paper proposes a novel closed-loop control approach capable of g...

Several pulsewidth modulation (PWM) strategies have been proposed for the three-level three-phase diode-clamped DC-AC converter. Among them, the nearest-three virtual-space-vector PWM guarantees the DC-link capacitor voltage balance under any operating condition, provided that the addition of the three phase currents equals zero. This paper extends...

This paper presents a new and simple finite-states model predictive control strategy for a four-level three-phase diode-clamped inverter. This strategy allows for fast load current control while keeping the balance of the dc-link capacitor voltages. A discrete-time model of the load and of the dc-link capacitors is used to predict the behavior of t...

Due to the increase of the distributed power generation in recent years, power system operators have updated their grid connection requirements, in order to include distributed power generation plants operation in the transient operation control of the overall electric power system. Among them, low voltage ride-through requirements demand wind powe...

In the previous literature, the introduction of the virtual space vector concept for the three-level three-leg neutral-point-clamped converter has led to the definition of pulsewidth modulation (PWM) strategies guaranteeing the dc-link capacitor voltage balance under any type of load, with the only requirement being that the addition of the three p...

This paper presents a closed-loop control scheme for the three-level three-phase neutral-point-clamped dc-ac converter using the optimized nearest three virtual-space-vector pulsewidth modulation, which is a modulation that produces low output-voltage distortion with a significant reduction of the dc-link capacitance. A new specific loop modifying...

This paper proposes a control approach to achieve balanced grid currents in three-level voltage-source inverters connected to the utility under dip or unbalanced condition. Fast sequence separation method for symmetrical components is used concurrently with linear quadratic regulator in the current controller, in order to take advantage of the mult...

This work introduces a fast symmetrical components separation method, in order to obtain instantly positive and negative phase sequence. Therefore, intrinsic delay presents in other sequence detection methods, like delayed signal cancellation, is removed. Accurate positive and negative phase-sequence components are obtained with the proposed method...

This work introduces a fast symmetrical components separation method, in order to obtain instantly positive and negative phase sequence. Therefore, intrinsic delay presents in other sequence detection methods, like delayed signal cancellation, is removed. Accurate positive and negative phase-sequence components are obtained with the proposed method...

This paper presents a new pulsewidth modulation (PWM) for the complete control of the neutral-point voltage in the three-level three-phase neutral-point-clamped (NPC) direct current-alternating current (dc-ac) converter. The balancing of the neutral-point voltage is achieved over the full range of converter output voltages and for all load power fa...

Several pulsewidth modulation strategies have been proposed for the three-level three-phase diode-clamped dc-ac converter. Among them, the nearest-three virtual-space-vector (NTV²) pulsewidth modulation (PWM) guarantees the dc-link capacitor voltage balance under any operating condition, provided that the addition of the three phase curr...

Low voltage ride-through requirements demand wind power plant to remain connected to the network in presence of grid voltage dips. Most of dips present positive, negative and zero sequence components. Then, the use of regulators based on symmetrical components is a good tool to control grid-connected converters, under grid fault condition. This wor...

Grid connection requirements established by power system operators have been updated in recent years, in order to include distributed power generation plants operation in the transient operation control of the overall electric power system. Among them, low voltage ride-through requirements demand wind power plant to remain connected to the network...

Low voltage ride-through requirements demand wind power plant to remain connected to the network in presence of grid voltage dips. Most of dips present positive, negative and zero sequence components. Then, the use of regulators based on symmetrical components is a good tool to control grid-connected converters, under grid fault condition. This wor...

In the previous literature, it has been reported that it is not possible to guarantee the balance of the dc-link capacitor voltages of three-phase diode-clamped multilevel dc-ac converters with passive front-ends for high modulation indices, especially for more than three levels. This paper proposes a novel closed-loop control approach capable of g...

Grid connection requirements established by power system operators have been updated in recent years, in order to include distributed power generation plants operation in the transient operation control of the overall electric power system. Among them, low voltage ride-through requirements demand wind power plant to remain connected to the network...

Several pulsewidth modulation strategies have been proposed for the three-level three-phase neutral-point-clamped DC-AC converter. Among them, the nearest-three virtual-space-vector (NTV² ) pulsewidth modulation (PWM) guarantees the DC-link capacitor voltage balance under any operating condition, provided that the addition of the three p...

This paper presents a novel approach for the connection of renewable energy sources to the utility grid. Due to the increasing power capability of the available generation systems, a three-level three-phase neutral-point-clamped voltage-source inverter is selected as the heart of the interfacing system. A multivariable control law is used for the r...

Inverters with power electronics converters are the main elements used to connect systems that obtain DC (wind energy, photovoltaic, fuel cells, among others) to the grid. On the other hand, most of the loads connected to these networks consist of rectifiers that feed loads whit DC consumptions (electronic equipments). The present work studies the...

This paper presents a closed-loop control scheme for the three-level three-phase neutral-point-clamped DC-AC converter using the optimized nearest-three virtual-space-vector pulsewidth modulation, a modulation that produces a low output voltage distortion with a significant reduction of the DC-link capacitance. A specific loop modifying the modulat...

A new Direct and Quadrature current decoupling strategy is presented which uses a filtering block placed between the current regulation and the modulation stages. This decoupling system is very easy to implement and it represents a clear improvement over the conventional feedforward method in relation to the closed loop system stability, the achiev...

A new Direct and Quadrature current decoupling strategy is presented which uses a filtering block placed between the current regulation and the modulation stages. This decoupling system is very easy to implement and it represents a clear improvement over the conventional feedforward method in relation to the closed loop system stability, the achiev...

This paper proposes a new control scheme for the neutral-point balance in single-phase three level neutral-point clamped converters. The control is addressed, considering the plant under study a non-linear time-variant system and applying a quasi-exact linearization to it. This way it is possible to apply classic control techniques. The method depi...

A new method for guaranteeing the capacitor voltage balance in a three-level AC/DC single-phase converter is presented. Using a nonlinear control loop and combinations of redundant switching functions, the capacitor charge balance for any power factor is achieved. Experimental results validate the performance of this proposal.

A load voltage and output current control for the three-level neutral-point-clamped (NPC) VSI is presented in this work. In usual operation, the regulator controls the voltage applied to the load. If an overcurrent occurs, the regulator will switch to current mode controller and the current will be driven to an acceptable value. A multivariable mod...

A load voltage and output current control for the Three-Level Neutral-Point-Clamped (NPC) VSI is presented in this work. In usual operation, the regulator controls the voltage applied to the resistive load. If an overcurrent occurs, the regulator will switch to current mode controller and the current will be driven to an acceptable value. A multiva...

Keeping charge balance among its two capacitors is a very important issue in an ac-dc three-level Neutral-Point-Clamped (NPC) converter, apart from controlling the dc-link voltage and the input power factor. To this effect a new method for guaranteeing the voltage equalization of both capacitors in the case of a three-level ac-dc single-phase conve...

This paper introduces a new single-phase multilevel inverter with HF isolation and bi-directional power flow capability. The advantage is to provide compact HF isolation, without an additional dc-stage and with lower harmonic distortion in the load. Typical applications of this converter are: photovoltaic systems, fuel cell systems and small wind p...

This paper presents an overview of single-phase inverters developed for small distributed power generators. The functions of inverters in distributed power generation (DG) systems include dc-ac conversion, output power quality assurance, various protection mechanisms, and system controls. Unique requirements for small distributed power generation s...

Wind turbines are becoming more popular in the present energy scenario: there is a global blueprint to achieve a 12% of the world’s electricity from wind power by 2020. The trend on Wind Energy Conversion Systems (WECS) is marked by Multi-Megawatt variable-speed wind turbines, and the latest prototypes glimpse to overcome the barrier of 5MW. Howeve...

The paper discusses the analysis and control of single-phase AC systems by means of rotating frames. Two methods for the D-Q transformation are compared in terms of computational requirements, transient response and sensibility. One of the transformation methods is based on sine and cosine composition, while the other uses a bi-phase transformation...

This paper presents a new modulation approach for the complete control of the neutral-point voltage in the three-level three-phase neutral-point-clamped voltage source inverter. The balancing of the neutral-point is achieved over the full range of converter output voltages and for all load power factors with the minimum output voltage distortion at...

DC/AC converters with high-frequency isolation and bidirectional power flow are extensively used in photovoltaic power systems and small isolated power converters at low and medium power ranges. The main disadvantages of these circuits are: high freewheeling loss of the primary leakage current, limited ZVS range for the lagging leg switches, the ef...

This paper introduces a new AC/AC multilevel converter for a single-phase inverter with high-frequency isolation and bidirectional power flow capability. The advantage is to provide compact HF isolation, without an additional DC stage and with lower harmonic distortion in the load. Higher efficiency and better dynamic response are possible as well...

One of the main features to consider in the development of new pulsewidth modulations (PWM) for multilevel converters is the high-frequency output-voltage distortion. In this letter, a novel per-switching-cycle figure, the harmonic distortion of order n for switching cycle k(HD_n,k), is introduced to quantitatively characterize the output...

This letter presents a new modulation approach for the complete control of the neutral-point voltage in the three-level three-phase neutral-point-clamped voltage source inverter. The new modulation approach, based on the virtual space vector concept, guarantees the balancing of the neutral-point voltage for any load (linear or nonlinear) over the f...

A new method to design a regulator for the complete large-signal control of the three-level neutral-point-clamped (NPC) VSI is presented in this work. For the regulator calculation, a comprehensive multivariable model of the NPC-VSI converter is used. The referred model is general and can be applied to generic types of sources, filters and loads. N...

This paper introduces a DC/AC converter with high-frequency isolation and bidirectional power flow capability for photovoltaic energy applications. The topology is based on a high-frequency inverter, a high-frequency transformer and an AC/AC converter. No additional DC-link stages are required, providing a reduction of components. A modulation stra...

This paper studies the connection of a photovoltaic energy system to the AC mains by means of a 3-level voltage source inverter (VSI). A proposal for modeling and controlling the inverter is presented, in order to have full controllability of the power transfer and the DC-link voltage balance. The steady-state, the transient analysis and the large-...

A simple and effective method to design a regulator for the complete large-signal control of the three-level neutral-point-clamped (NPC) VSI is presented. For the regulator calculation, a comprehensive multivariable model of the NPC-VSI converter is used. The control strategy is based on linear quadratic regulator (LQR) and gain-scheduling control...

An accurate model in order to simulate a nonideal inverter is complex. In this work, a Simulink model is proposed. The model implements all the structure of the power inverter and the nucleus of calculation of the modulation of the inverter to obtain the induction motor voltage. This paper also studies the feasibility of knowing the specified volta...

An approach for the large-signal and complete control of the Neutral-Point-Clamped VSI is presented. A comprehensive mathematical multivariable model is used in this work. The model is general and can be applied to generic types of sources, filters and loads. No information about the system is lost with this model. A simple and effective method to...

En este artículo se presenta el estudio y la simulación de un convertidor CC/CA monofásico con aislamiento galvánico utilizando el modelado en el espacio de estado, promediado, con transformación de coordenadas D-Q y aplicación de la técnica de control óptimo cuadrático. Se aplica la modulación senoidal de anchura de pulso. Se presentan resultados...

This paper deals with the analysis, design and operation of a control system for a single-phase three-level rectifier with a neutral-point-clamped (NPC) topology. Usually the desired operating conditions for this type of converter are: unity displacement factor, output DC voltage regulation and neutral point voltage balancing. A d-q reference frame...

A simple and effective method to design the control strategy for a Three-Level VSI is introduced. Linear Quadratic Regulator (LQR) and Gain-Scheduling techniques work concurrently in the regulator. Any state variable can be regulated using the proposed method, either in small and large-signal operation. With the model and regulator presented, DC-li...

Three-Level VSIs present multivariable structure. Thus, control of these converters is interesting to be implemented using multivariable techniques. This work introduces a novel and simple method for the design of a controller using LQR and gain-scheduling techniques. The method allows the control of any state variables and the controller can opera...

A vector control based single-phase half-bridge boost converter circuit operating at a fixed high switching frequency is proposed in order to obtain a unity power factor (PF) and a balanced operation of the DC-link capacitors. In most cases this structure is controlled via a hysteresis comparator and a current sensor. Moreover, to prevent any imbal...

A design DC/DC boost zero-voltage-transition (ZVT) pulse-width modulation (PWM) converter using some design optimization criteria is presented. These design optimization criteria take into account a series of characteristics, and can choose between converters that use soft-switching technique. The design optimization criteria use a designated cost...

The dynamic characteristics of three-level voltage-source inverters are analyzed, in order to control the power delivered to the load in closed-loop operation. A model of the three-level voltage-source inverter is presented. The dynamics of the complete system is considered, including the DC-link and the load side. The model uses D-Q transformation...

A solar battery charger using a DC/DC resonant converter with 3 reactive elements operating over a wide load range is presented. This charger is based on a half bridge inverter structure and it can be fed by a solar panels system configured as two current sources, An experimental 100 W/250 kHz unit was built and tested in the laboratory. The operat...

A generalized approach for the steady-state analysis of DC/DC and DC/AC resonant converters is presented. The analysis can be used for topologies with voltage or current source at the input. Different modulation techniques can be considered: variable switching frequency modulation and duty-ratio modulation. All topologies with 2 and 3 resonant elem...

A typical spacecraft power distribution system with an AC bus is defined by: Solar array, batteries discharge regulator (BDR), batteries charge regulator (BCR), transmission line, the DC/DC converter to regulate the DC bus or to track the maximum power point of the solar array, the DC/AC converter to regulate the distribution line, and some loads w...

The specifications for a spacecraft power distribution system are: high efficiency, long life and reduced size and weight. From the regulation point of view, it will be necessary to control the operating point of the solar array, the charge and discharge of the battery, to have a good line regulation capability and eventually to have an isolation b...

In many conventional applications voltage mode control has been used for closed loop regulation of switching converters. Nevertheless, in last years technical literature on the subject [1], [2] shows an increasing number of works dealing with current control mode applications and some IC's have appeared on the market allowing analog implementations...

A new and comprehensive model of the three-level voltage-source inverter is presented. The dynamics of the complete system is considered, including the DC-link side and the load side. This model is a tool for a full control of the system. The model uses the D-Q transformation. Steady-state and small-signal analysis are obtained and the simulation r...