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This chapter is based on the Annual Report on Public Accounts prepared by the Maltese National Audit Office (NAO), Malta’s Supreme Audit Institution. Its objectives are to analyse and classify the reported issues, evaluate their significance and how the findings are reflected in the Public Sector, and assess the adequacy of the communication of these findings through the Annual Report. The research consisted of a qualitative analysis of the Annual Reports for the three years 2007, 2009 and 2011. This analysis was supplemented by unstructured interviews conducted with both NAO and Government officials. Findings report a significant number of issues emerging from different factors. The highest incidence of weaknesses was related to record-keeping and compliance with policies and procedures. Moreover, the interviews with NAO officials showed that the departments were not always taking on board the recommendations made through the Annual Reports, thus indicating a passive attitude towards the reported findings. The results also show that while the Government has its own structures of checks-and-balances to prevent and detect errors, and no internal control system is completely effective, there is still much room for improvement within the Public Sector to ensure that public funds are appropriately utilised. The detection of various issues by the NAO is therefore inevitable, particularly given the complexity and size of the Public Sector. In conclusion, the NAO findings should be more thoroughly examined to reduce the incidence of issues. Furthermore, the way forward should be directed at enhancing the current systems and promoting a more positive relationship between the NAO and auditees.

High-temperature (HT°) motors are made with inorganic coils wound with a ceramic-coated wire. They must be carefully designed because the HT° insulating materials have a lower breakdown voltages than the polymers used for insulating standard machines.

The voltage distribution between stator coils is computed with high-frequency (HF) equivalent circuits that consider the magnetic couplings and the stray capacitances. Two time scales are used for getting a fast computation of very short voltage spikes. For the first step, a medium time scale analysis is performed considering a simplified equivalent circuit made without any stray capacitance but with the full PWM pattern and the magnetic couplings. For the second step, a more detailed HF equivalent circuit computes voltage spikes during short critical time windows.

The computation made during the first step provides the critical time windows and the initial values of the state variables to the second one. The rise and fall time of the electronic switches have a minor influence on the maximum voltage stress. Conversely, the connection cable length and the common-mode capacitances have a large influence.

HF equivalent circuits cannot be used with random windings but only to formed coils that have a deterministic position of turns.

The proposed method can be used designing of HT° machine windings fed by PWM inverter and for improving the coils of standard machine used in aircraft’s low-pressure environments.

The influence of grounding system of the DC link is considered for computing the voltage spikes in the motor windings.