The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory. Athena is a versatile observatory designed to address the Hot and Energetic Universe science theme, as selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), X-IFU aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over a hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR (i.e. in the course of its preliminary definition phase, so-called B1), browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters, such as the instrument efficiency, spectral resolution, energy scale knowledge, count rate capability, non X-ray background and target of opportunity efficiency. Finally, we briefly discuss the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, touch on communication and outreach activities, the consortium organisation and the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship

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This paper presents main problems of practical implementation of filed oriented control (FOC) dedicated for a permanent magnet synchronous motor (PMSM). By means of this work, elements of FOC's mathematical model and practical implementation of the electronic commutator are presented. It is based on the DSP processing unit IGBT power module. The measurement system consists of control unit equipped with inverter and encoder. The main element of driving system is PMSM drive. There are two main problems addressed in this paper: electromagnetic distortions and proper calculations in real systems. This work is intended to resolve these problems. Described solutions have been implemented and examined practically.

In the present work, two approaches for the phase current measurement of a permanent magnet synchronous motor (PMSM) were compared. The measured phase current was distorted by glitches, and a software method to eliminate these glitches was necessary. An averaging of samples was carried out, and the experimental results indicated that averaging was essential for further calculations. Moreover, the PMSM operated smoothly, and the difference between the set point and the actual speed was reduced for the full range of loads from the free run up to a full load. The increasing popularity of field-programmable gate array (FPGA) devices has encouraged developments in PMSM controllers using a direct hardware approach and the classic software approach utilizing a digital signal processor unit. In this study, the selected performance of TMS320F2812 and Spartan-3E were compared. This paper proposes an original adaptive correction method for a current transducer.

The paper explains how to select the best PWM control frequency for specific Permanent Magnet Synchronous Motors (PMSM) to achieve its maximum efficiency. Examinations were carried out for a PMSM unit with the power of 1 kW, rated speed of 1000 rpm and rated torque of 6 Nm. The PWM frequency ranged from 4 kHz to 20 kHz with the increment of 1 kHz. Measurements were taken for each of the foregoing frequencies, for the load torques of 2 Nm, 4 Nm and 6 Nm and for the rotation speeds of 300 rpm, 500 rpm, 750 rpm, 1000 rpm and 1200 rpm to find out efficiency of the PMSM motor. The achieved results make it possible to properly adjust the PWM control frequency for each PMSM motor to operate the motor in the most efficient way and, in consequence, save energy consumed by that motor.