Influence of the amount of permanent-magnet material in fractional-slot permanent-magnet synchronous machines

The efficiency of permanent-magnet (PM) synchronous machines with outer rotor and concentrated windings is investigated as a function of the mass of magnets used, keeping the power, volume, and mechanical air-gap thickness constant. In order to be useful for electric vehicle motors and wind turbine generators, the efficiency is computed in wide speed and torque ranges, including overload. For a given type and amount of magnets, the geometry of the machine and the efficiency map are computed by analytical models and finite-element models, taken into account the iron loss, copper loss, magnet loss, and pulsewidth-modulation loss. The models are validated by experiments. Furthermore, the demagnetization risk and torque ripple are studied as functions of the mass of magnets in the machine. The effect of the mass of magnets is investigated for several soft magnetic materials, for several combinations of number of poles and number of stator slots, and for both rare earth (NdFeB) magnets and ferrite magnets. It is observed that the amount of PM material can vary in a wide range with a minor influence on the efficiency, torque density, and torque ripple and with a limited demagnetization risk

Eddy current based, contactless position transducer for a gas handle

In electric vehicles, it is normal to have an electronic set value for 'gas' and for 'brake'. Traditional potentiometers with sliding contacts are not reliable. Magnetoresistive sensors or hall effect sensors need a magnet on the moving part. The proposed sensor just needs iron on the moving part. It uses an oscillator circuit where the absorbed current is an indication of damping, so how close the iron is to the sensor. The component cost is low and the output has a soft gradual change with the displacement

From afterthought to centerpiece::The WTO Appellate Body and its rise to prominence in the world trading system

This paper deals with the Appellate Body of the World Trade Organization and its rise to prominence in the world trading system. The Appellate Body was not conceived by the Uruguay Round negotiators as the centerpiece of the WTO dispute settlement system. It was more an afterthought, linked to the introduction of the quasi-automatic adoption of panel reports under the new dispute settlement system. In little time, however, the Appellate Body grew into the most important and authoritative organ of WTO dispute settlement. The Appellate Body is now, in all but name, the World Trade Court. The significance of its contribution to the development of international trade law is generally recognized. Critics even accused the Appellate Body of having engaged in judicial legislation. This paper does not seek to assess whether the Appellate Body did indeed exceed its judicial mandate. The purpose of this paper is to recall the unassuming origins of the Appellate Body and to discuss the factors that have contributed to its rise to prominence over the last decade. These factors are multiple and often closely related. They include the first and subsequent compositions of the Appellate Body; the Working Procedures for Appellate Review; the early embracement and consistent application of the rules of interpretation of the Vienna Convention; the frequent and broad recourse to appellate review; the manner in which the Appellate Body used its authority of appellate review; and, finally, the case law of the Appellate Body to date, and in particular the case law balancing free trade and other societal values and the case law ensuring the fairness and effectiveness of the WTO dispute settlement system. It is important to identify and correctly appreciate these factors because the Appellate Body will retain its current status and role in the world trading system only to the extent that these factors continue to be sufficiently present

Rules on NGO accreditation:Do existing legal arrangements facilitate the legitimization of the role of NGOs in international organisations?

This article examines the involvement of non-governmental organisations NGOs with a number of selected international organisations and the rules on NGO accreditation currently applied by these international organisations. It is submitted that appropriate legal arrangements for accreditation of NGOs facilitate the legitimization of their role in international organisations. None of the examined international organisations have currently implemented fully appropriate legal arrangements for the accreditation of NGOs. The arrangements implemented by the UN Economic and Social Council, however, set a good example for other international organisations and form an excellent basis for further improvement

Can the WTO Dispute Settlement System Be Revived? Options for Addressing a Major Governance Failure of the World Trade Organization.

The dispute settlement system of the WTO is, due to the paralysis of the WTO Appellate Body, in an existential crisis. This crisis is a major governance failure of the WTO. At the Ministerial Conference in June 2022, WTO Members committed themselves to address this failure. This paper deals with past and present efforts to restore the WTO dispute settlement system and examines, more generally, the options available to WTO Members to overcome the current crisis. It also discusses the MPIA, which may be in the coming years the best hope for rules-based, binding dispute resolution among WTO Members

Optimization of motor and gearbox for an ultra light electric vehicle

The integrated design of the drivetrain of a single person ultra light electric vehicle powered by batteries is optimized towards high efficiency and low mass. The drivetrain of each front wheel consists of an outer rotor permanent magnet synchronous motor (PMSM), a gearbox and the power electronics with converter and control print. The complete drivetrain is optimized for the New European Driving Cycle and the Federal Test Procedure. For the optimization of the complete drivetrain analytical models are used to calculate the losses and the efficiency. The analytical models are fast, and useful for designing a good PMSM in combination with a gearbox. The optimization of the drivetrain over the driving cycles makes it possible to choose the optimal combination of motor and gearbox for different gear ratios in order to have high efficiency and low weight. Comparing a single-stage gearbox with a twostage gearbox, a single-stage gearbox has a higher efficiency, but also a higher weight than a two-stage gearbox with the same properties. The optimization of the dynamic behavior of the drivetrain over the driving cycles yields a compromise between the total efficiency and the total mass of the drivetrain. The optimum choice will depend on the intended use of the vehicle (drive cycle)