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The control of a tandem voltage source inverter applied to traction drives is presented in this paper. It allows to manage the power flows from and to two separate energy storage units: batteries and supercapacitors. By means of the proposed control, it is possible to recharge the supercapacitors also during the normal runs of the vehicle, without overloading the batteries and with no additional power equipments.

This paper describes a novel FPGA (Field Programmable Gate Array) based control system for MSAF (Motor Side Active Filter). The MSAF is based on the active filtering approach and its main task is to obtain an optimized power sharing between two Voltage Sources Inverters (VSIs). This solution allows to obtain an optimal VSI parallel connection both reducing the total switching losses and, in the same time, improving the quality of the motor currents. In this paper particular attention is paid to the implementation of a high performance FPGA based current controller (500kHz). Simulated and experimental results are given and discusses.

In the paper, an intelligent set-up for PWM rectifiers is proposed. It is based on a predictive estimation control algorithm which guarantees the imposed value of the dc link output voltage and, at the same time, a unity power factor behaviour at the mains. Besides, a particular blank time free digital space vector modulator is described which eliminates the drop voltage due to the dead time effect and, also, avoids the current zero clamping phenomenon. Improvements on the AC source current waveforms and dc bus voltage are achieved with the proposed system, as shown in the experimental analysis.

The high speed range control techniques of permanent magnet surface mounted (PMSM) ac machines, generally need an accurate determination of machine parameters at the designing stage of the control hardware and software. In fact, wrong values of some machine parameters can heavily effect the drive performances. Generally, PMSM ac machine are analysed by using a non salient model. This hypothesis is correct if it is possible to neglect the iron saturation due the rotor field. But when high field magnets are mounted on the rotor surface, different saturation conditions could occur in the stator iron along dand q- axis, and therefore a salient model has to be considered for a correct modelling of the PMSM machine. Particularly, different values of d- and q- axes inductances can be taken into account. The above phenomenon, if not considered, could introduce errors in terms of torque and current tracking especially if a high speed range is required. A self-commissioning algorithm is presented in the paper, which allows the determination of the parameters of saturated PMSM machine fed by a VSI. The proposed algorithm can be easily implemented and can be split in a start-up routine and an on-line procedure. In this way, a precise and quick evaluation of the motor parameters can be achieved, as shown by the experimental results.

H_infinity optimisation synthesis is a very important and powerful tool for designing robust controllers. The authors consider the position control of a DC drive using H_infinity-control theory. It is applied to the design of a position controller for a DC drive. In particular, the problem of finding an 'optimal' H_infinity controller is considered. The validity of the design procedure and the robustness of the proposed controller are venfied by means of computer simulation and experimental analysis.

A fully integrated board for resolver-to-digital conversion is proposed in this paper. It is based on a combined analog/digital circuit, which allows one to track the shaft angle of a standard resolver in a digital form. Furthermore, the board also provides the feeding signal for the resolver-rotor circuit. All the tuning and configuration settings, which allow one to adapt different kind of resolvers to the proposed system, can be easily implemented directly on the board. The final assembly is a compact low-cost resolver-to-digital converter. The entire board design and implementation are described in this paper. In addition, several tests at different resolver speeds have been performed for validation.

A novel high-efficiency space vector modulation (SVM) strategy is proposed in this paper. It is based on the simultaneous and combined use of two strategies. The former consists of commutating only one switch of each inverter leg within each modulation period. In this way, there is no need to impose the dead time. The latter performs a step-by-step change of the modulation frequency in order to reduce the distortion of the inverter output voltage. The proposed system has been implemented and carried out on a programmable logic device (PLD) digital board. For validation, an experiment has been set up and several tests have been performed. The results have been compared with the ones achieved by means of the traditional SVM technique.

A predictive algorithm is presented in this paper, which allows the compensation of the dead-time effects in a voltage-source inverter feeding an induction motor, with space-vector pulsewidth modulation. It is based on the modification of the reference space vector of the feeding voltage according to a step-by-step analytical prediction of the stator phase currents. In this way, the effects of the dead time can be taken into account and compensated. The validity and feasibility of the proposed algorithm are confirmed by simulation and proved by experimental implementation.

In this paper a novel predictive control for parallel power factor correction (PFC) scheme is proposed. It is based on an optimized power sharing where the active filtering approach is used in order to increase the current quality and, at the same time, to reduce the switching losses. A prototype of parallel PFC controlled by a DSP was set up to implement the proposed control strategy. Both the simulation and experimental results show that the proposed approach achieves near unity power factor and a not negligible switching losses reduction.

In this paper a novel power factor correction (PFC) dual boost scheme is proposed. It is based on an optimized power sharing where the active filtering approach is used to increase the current quality and at the same time to reduce the switching losses. A prototype of dual boost PFC controlled by a FPGA evaluation board was set up to implement the proposed control strategy. Both the simulation and experimental results show that the proposed strategy for PFC achieves near unity power factor and a not negligible switching losses reduction.

A high performance modulation technique for dual cascaded inverter is presented in this paper. It allows to optimize the converter performances in terms of power losses and harmonic content. A numerical analysis and an experimental implementation on a laboratory prototype fully confirm the validity of the proposed modulation technique.

An autotuning system, which takes into account the self-compatibility of power converters, is proposed in this paper. It is based on a startup routine and a self-disturbance evaluation board, which selects the optimal switching frequencies for the power converter in order to decrease the internal disturbances in terms of electromagnetic interference between the power section and the control one. The entire test and tuning system does not require any field or current sensor but just digital comparators and counters. This configuration allows achieving a robust and low-cost autotuning system for internal compatibility of power converters.

A high efficiency conversion system based on super-capacitor energy recover and power factor correction (PFC) is proposed for motion system, such as elevators. It allows to greatly improve the elevator performances in terms of energy efficiency and power demand, allowing the compliance with the IEC-1000-3-2 and IEEE-519 international standard on the power quality.

Motor side active filter (MSAF) is a novel solution for high performances or high power motor drives. It is based on the parallel connection of two or more voltage source inverter (VSI) controlled with an active filtering approach. In this way an optimized power sharing can be performed. This approach can be used to improve the converter efficiency in application where either high power or high switching frequency is required. In this paper special attention is paid to the hardware implementation of the MSAF on a low cost and high performances FPGA (field programmable gate array) based control system. Experimental results are given and discusses.

In this paper a novel and high efficiency conversion system based on a Supercapacitor Recover System (SRS) and a Power Factor Correction circuit (PFC) is proposed and tested. It allows to greatly improve the performances of motion systems for residential application, such as elevators, both in terms of energy efficiency and power demand, allowing the compliance with the recents international standards on power quality.

In this paper, a high performance modulation technique for dual inverter with separate dc sources feeding open-end winding induction motors is proposed. It is based on a optimization algorithm, which carries out the suitable modulation pattern for the dual inverter in order to minimize power losses. In this way, it is possible to optimize the performance, especially for high power applications.

Analysis of the internal electromagnetic compatibility of digitally controlled power converters is discussed. In particular, the optimum layout of the circuit configuration is designed on the basis of the actual electromagnetic interference between the power and the control section of a power converter. Besides, further improvements can be achieved by means of an auto-tuning additional board, which scans all the possible converter switching frequencies and analyses the distortion on the control signals corresponding to each frequency. Its main task is to select only the ones which produce low disturbances on the control signals as operating frequencies for the converter.

A novel approach to the parallel connection of VSI, called MSAF (Motor Side Active Filter) with predictive control is presented and analysed. It allows to reduce both the power module switching losses and to improve the quality of the motor currents. In particular, the active filtering approach is used in order to compensate the effects, on a synchronous machine, of a voltage source inverter operating with a low switching frequency. The improvement introduced by the proposed solution is an optimizated power sharing in a VSI parallel connection. This power sharing is performed in order to allocate the most part of the load current to a VSI operating at a low switching frequency, while a second VSI, operating as an active filter, supplies only a small part of the load current. Simulated and experimental results are described.

A high efficiency converter topology is proposed in this paper. It has been designed and implemented for a particular application, in which the converter has to work in very critical external condition, such as anti-fire systems. The features to be achieved are the following: dc/ac conversion from a low voltage input source and a minimization of the conversion losses. A prototype has been manufactured and tested in laboratory, for validation and performances evaluation.

In this paper, a novel high pertormances modulation unit for high power multi drive application is presented. It is mainly based on a intelligent PLD (Programmable Logic Device) based modulator connected via filed bus to several slave power units. The PLD master unit is characterized by a multi modulation strategy which implements a double strategy: a variable frequency technique, whose target is to change the switching frequency on the base of the power modules dead time and a ''single switch commutation technique", which allows to almost completely eliminate the blank time imposition during the switching operation. The proposed technique has been tested in a high performances parallel connection of VSI (Voltage Source Inverter).

In this paper a novel solution for exploiting the performances of high power synchronous drives is proposed and tested. In particular the active filtering approach is used in order to obtain an optimized power sharing between two Voltage Sources Inverters (VSIs). The proposed solution, called Motor Side Active Filter (MSAF), allows to reduce the total switching losses and in the same time improve the quality of the motor currents. Particular attention is paid to the common mode currents, which circulation can mainly influence the system performances. Simulated and experimental results are given and discusses.

This paper deals with the analysis of the internal electromagnetic compatibility of ac drives fed by voltage source inverters. In particular, the optimum layout of the circuit configuration is designed on the base of the actual electromagnetic interference between the power and the control section of a power converter. Besides, further improvements can be achieved by means of an auto-tuning additional board, which scans all the possible converter switching frequencies and analyze the distortion on the control signals corresponding to each frequency. Its main task is to select as operating frequencies for the converter only the ones which produce low disturbances on the control signals. The combination of the internal EMI analysis and the auto-tuning system allows to achieve very efficient power converters.

In this paper, an auto-tuning system, which takes into account the self-compatibility of power converters, is proposed. It is based on a start-up routine and a self-disturbances evaluation board, which selects the optimal switching frequencies for the power modules in order to avoid internal disturbances in terms of EMI between the power section and the control one. The entire test and tuning system does not require any field or current sensor, but just digital comparators and counters. This configuration allows to achieve a robust and low cost auto-tuning system for internal compatibility of power converters.

A novel application of the active filtering approach is proposed in this paper. It is based on the combination of two voltage source inverter (VSI) feeding an high power induction machine. The active filtering approach is used to compensate the effects, on an induction machine, of a VSI operating with a low switching frequency. The improvements introduced by the proposed solution are a reduced switching losses and an improved quality of the motor currents. In the paper the performances of the proposed motor side active filter (MSAF) are illustrated by using simulated and experimental results.

A self tuning system for internal electromagnetic compatibility of ac drives fed by voltage source inverters is proposed in this paper. It is based on a hardware equipment and a software algorithm, which runs as start-up routine for the drive. It performs the auto-tuning test on the power and control section of the converter and selects the optimal switching frequencies for the power modules in order to avoid internal disturbances in terms of EMI.

In this paper, a novel modulation technique for voltage source inverter feeding induction motor drives is presented. It is mainly based on a variable frequency technique, whose target is to change the switching frequency on the base of the power modules dead time distortion. Besides, this modulation is combined with the “single switch commutation technique”, which allows to almost completely eliminate the balnk time imposition during the switching operation. The proposed technique has been implemented by means of a digital modulator and several tests have been performed in order to verify the validity of the proposed modulation technique.

A novel optimized space vector modulation for voltage source inverter fed induction motor drives, based on an adaptive modulation frequency selection algorithm, is presented in the paper. It considerably reduces the drop voltage due to the dead time effect of the inverter power modules and allows to increase the overall drive performances. The proposed system has been manufactured on a Programmable Logic Device digital board. For validation, an experiment has been set up and several tests have been performed. The results have been compared with the ones achieved by means of the traditional space vector modulation technique.

Recent developments in the field of supercapacitors make very promising the use of these equipments in a large range of applications. In particular, it is useful to introduce supercapacitors in all the drive applications, in which an energy recovery it is possible. In this paper, a predictive control of the supercapacitor storage system is proposed and tested in the field of the automatic warehouse. Experimental results show the increased performances of the systems thanks to supercapacitors energy recovery capability.

Pulsewidth modulated voltage source inverter can be easily controlled in such a way as to achieve the desired value of the output voltage and/or current, but they exhibit high switching losses when operated at high switching frequencies. Besides, relevant electromagnetic interferences can be produced because of the high di/dt and dv/dt in the converter waveforms. These problems can be partially or totally eliminated if the converter switches are commutated at zero voltage and or zero current. This is achieved by means of suitable tuned LC resonant circuits. In this paper, a novel topology of quasi-resonant dc link for soft switching of VSI is proposed. It is based on two resonant circuits: a main one, which makes the voltage oscillating around the main dc bus voltage, and which is commutated at zero current, and an auxiliary circuit which is enabled to drive the dc voltage to zero just when an inverter switch commutation occurs. Dead time imposition is fully taken into account. A detailed experiment investigation has been performed for validating the proposed scheme.

An optimized set-up for controlling PWM rectifiers is proposed in this paper. In particular, the control part is based on a predictive estimation algorithm which guarantees the imposed value of the dc link output voltage and, at the same time, a unity power factor behavior at the mains. The modulation part consists on a digital space vector modulator, which eliminates the drop voltage due to the dead time effect and, also, avoids the current zero clamping phenomenon. The results achieved by means of an experiment confirm that improvements on the AC source current waveforms and controllable dc bus voltage are achieved with the proposed system.

A novel predictive control algorithm, for drives including sinusoidal permanent magnet motor is proposed in this paper. It is based on the instantaneous values mathematical model of the machine, and allows to exploit the drive performances both in steady-state and in transient operations, by fully satisfying the instantaneous voltage and current constraints. The algorithm validation has been performed by means of experiment analysis. The results show an improvement of the dynamic performances achieved with the proposed control, thanks to a very low ripple of the machine output torque.

A low cost digital modulator for SVM which allows the hardware compensation of the dead time effects is presented. It consists of a fully integrated digital set-up implemented on a programmable logic device. It is based on an adequate modification of the switching sequence generation on the base of the phase stator current signs and of the power modules status.

For medium-low power applications, Permanent Magnet AC (PMAC) machines drives fed by VSI represent a valid solution. For this kind of motors, in order to expand the speed limit over the base value, a field weakening has to be performed. In this paper, the description of the experimental implementation of a control algorithm which extend the machine speed range of a PMAC machine is presented. Experimental results confirm the feasibility of the experiment layout, of the proposed approach and the possibility of achieving very high dynamic performances.

An optimized modulation technique which is specific for PWM-rectifiers is proposed in this paper. It is based on the imposition of modulation frequencies different for the three rectifier legs, selected according to the power modules commutation losses. A reduction of the current harmonic content and an improvement of the overall system performances are achieved, as shown by means of an experiment implementation.

This paper presents a study of a predictive torque and flux control in the constant torque region and in the fieldweakening one of Permanent Magnet Alternate Machines (PMAC) fed by a Voltage Source Inverter (VSI). It is based on the step-by-step determination of the inverter feeding voltage as a function of the current references, by taking into account both the steady state and the transient electrical constraints. Experimental results confirm the validity of the proposed approach and the possibility of achieving very good dynamic performances.

A full-automatic hardware/software tool for parameters identification of an induction motor fed by a voltage source inverter is proposed. It is based on a DSP control board, an acquisition unit and an user-friendly software tool which allows an easy and fully automatic induction motor parameter identification to be run at the start up of the drive. The validity and feasibility of the proposed set-up have been confirmed by experimental implementation. In particular, two induction motors of standard construction have been tested and the results compared with the ones achieved by means of a traditional identification method.