Luca Sgarbossa

Automatic Tracking of MTPA Trajectory in IPM Motor Drives Based on AC Current Injection

The paper deals with a novel approach for the real-time tracking of the Maximum-Torque-Per-Ampere (MTPA) trajectory of an IPM motor drive. The proposed approach is based on the injection of proper tests signals and allows the MTPA trajectory to be learned and updated in the drive during steady-state conditions. The analytical development of the estimation algorithm, supported by a complete validation by simulation, is given in the paper. Finally experimental results are presented based on a prototype IPM drive system.

IPM Machine Drive Design and Tests for an Integrated Starter-Alternator Application

This paper deals with an integrated starter-alternator (ISA) drive which exhibits a high torque for the engine start, a wide constant-power speed range for the engine speedup, and a high-speed generator mode operation for electric energy generation. Peculiarities of this ISA drive are thus its flux-weakening capability and the possibility to large torque overload at low speed. The focus on the design, analysis, and test of an interior permanent-magnet motor and drive for a prototype of ISA is given in this paper. In details, this paper reports on the design of stator and rotor geometries, the results of finite-element computations, the description of control system, and the experimental results of prototype tests.

IPM Machine Drive Design and Tests for an Integrated Starter–Alternator Application

This paper deals with an integrated starter-alternator (ISA) drive which exhibits a high torque for the engine start, a wide constant-power speed range for the engine speedup, and a high-speed generator mode operation for electric energy generation. Peculiarities of this ISA drive are thus its flux-weakening capability and the possibility to large torque overload at low speed. The focus on the design, analysis, and test of an interior permanent-magnet motor and drive for a prototype of ISA is given in this paper. In details, this paper reports on the design of stator and rotor geometries, the results of finite-element computations, the description of control system, and the experimental results of prototype tests.

Automatic tracking of MTPA trajectory in IPM motor drives based on AC current injection

The paper deals with a novel approach for the real-time tracking of the Maximum-Torque-Per-Ampere (MTPA) trajectory of an IPM motor drive. The proposed approach is based on the injection of proper tests signals and allows the MTPA trajectory to be learned and updated in the drive during steady-state conditions. The analytical development of the estimation algorithm, supported by a complete validation by simulation, is given in the paper. Finally experimental results are presented based on a prototype IPM drive system.

On-line tracking of the MTPA trajectory in IPM motors via active power measurement

The real-time tracking of the Maximum-Torque-Per-Ampere (MTPA) trajectory in Interior-Permanent-Magnet (IPM) motors is addressed in this paper. The considered approach is based on the injection of proper current test signals and aims at minimizing torque oscillations at the injected frequency, this last condition assuring MTPA operations. Differently from previous approaches motor active power is monitored to detect the out-of-MTPA condition (i.e. torque oscillations), instead of measured motor speed, thus avoiding the use of high-resolution speed transducers, as required by previous approaches. Analytical development are provided, as well as simulation and experimental results, proving the effectiveness of the proposal.

Modelling and design of a direct-drive lift control with rope elasticity and estimation of starting torque

This paper deals with position control of a direct drive rope-based lift system at mechanical brake releasing. The electrical equipment includes a high-torque, low-speed permanent magnet synchronous motor with external rotor directly connected to the rope pulley. The drive uses only stator current sensors for torque control and an incremental encoder on the motor shaft. A detailed model of the system, which comprises also rope elasticity, is presented, as wells as a load torque estimation algorithm and a feedforward action on the torque reference signal. Such reference is used to reduce the cabin falling down at brake releasing below a perceptible threshold. Final experimental results support the mathematical theory outlined in the paper, validating the proposed control strategy.

Improvements in Power Line Communication Reliability for Electric Drives by Random PWM Techniques

Power line communication (PLC) techniques seem a worthwhile research issue not only in civil applications, but also into the industrial scenario. The realisation of a communication network using the already existing electrical network is attractive for cost benefits, even though it represents a real challenge. Major problems concern communication reliability, effectiveness of transmission modulation methods and algorithms for error correction. EMC issues also must be taken into account, considering the consequences of injecting high-frequency harmonics into the AC power distribution system. This paper deals with the application of PLC techniques to the harsh and noisy environment of electrical drives. This study points out how the improvements in communication reliability can be achieved not only by a smart choice of the communication protocol, but also by using proper inverter modulation techniques, as random space vector modulation. The experimental results of transmission tests with both conventional and random space vector modulation techniques are here presented and discussed.

Effective control of an Integrated Starter-Alternator with an IPM synchronous machine

This paper describes the control strategy of an integrated starter-alternator prototype. Control specifications include a high starting torque in the low speed range as well as a smooth transition from motor to generator operation mode at higher speed. Inverter voltage limitation has to be managed during high speed operation. An interior permanent magnet synchronous machine with a fractional-slot winding is adopted. The control strategy takes advantage of the magnetic model of the electrical machine, which is well suited for flux-weakening application with advantages for the power stage ratings. Details of the control design and experimental test results are reported.

High efficiency multi-drive system for a hybrid electric catamaran with submersed PM synchronous motors

A high efficiency system for a multi-drive hybrid electric catamaran is presented. Design choices are discussed in the first part of the paper. On board electric system and power flow are then detailed, illustrating the main components. In the second part of the paper, the distinctive sensorless control of the permanent magnet synchronous motor is described and validated by experimental results.

Design of a flux weakening control scheme for DC motor drives featuring full voltage operation

This paper deals with an effective drive control scheme for separately excited DC motors. Distinctive feature of the work is the modelling of the motor as a two-input single-output non linear system that allows the armature voltage to be maintained to the maximum full output voltage of the converter during flux weakening operation while the armature current is controlled by the excitation one. Experimental results confirm the expected drive performances that get advantages in sizing the power electronics.