Focusing on the classification of solar winds into three types of flux: (1) slow winds, (2) fluctuating winds, and (3) high speed-solar winds HSSW (V ≥ 450 km/s on average day), the influence of the convection electric field (E M ) via the flow of HSSWs during storms in the internal magnetosphere and on the stability of magnetospheric plasma at high latitudes was investigated. The study involved 1964-2009 period, which encompasses solar cycles 20, 21, 22 and 23. The results show a weak correlation of the frozen electric field profiles with the HSSWs overall solar cycles and a very large number of HSSWs recorded in cycle 23. Particular attention has been paid to solar cycle 22 which rather presents a fairly disturbed profile with sudden variations in solar flux and E M field; however, solar cycle 21 records the lowest level of HSSW.Overall, over all the studied solar cycles, it can be seen that the E M field from HSSWs of very low intensity increases progressively from solar cycle 20 to cycle 23, respectively with a minimum occurrence of 8.48% and a maximum of 9.36%. The results reached show, on one hand, that the magnetosphere is very stable from 15:00UT to 21:00UT, and on the other hand, that there is a significant transfer of mass in the night sector (21:00UT-24:00UT) than on the day side (00:00UT-15:00UT) for all solar cycles over the long period of 45 years.

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Earth's magnetosphere is a magnetic shield that protects the Earth from the energetic emissions of the high-speed Solar Wind (HSSW). We perform a statistical analysis of the response of Earth's magnetosphere inner part under the impact of HSSW over 40 years of data encompassing solar cycles 20-23. With misidentified events or events interacting with interplanetary coronal mass ejections (ICMEs) removed, only 23552 events were identified. The results we obtained show that more than 85% of the events recorded from 1964 to 2009 are generated by coronal holes (CHs). Almost all observations were confined between 250-800 km/s and show a unimodal distribution per solar cycle: (1) 93% of the solar wind (SW) velocities are on the order of 567.77 ± 2.46 km/s for solar cycle 20, (2) 81% of the SW velocities are worth 524.30 ± 2.69 km/s for cycle 21, (3) 92% of the SW velocities progress to 565.15 ± 2.72 km/s for cycle 22, and (4) 75% of the SW velocities show a value on the order of 530.38 ± 2.22 km/s for cycle 23. Furthermore, our analysis shows a lower electron density at the beginning of the cycle (48%) than at the end of the solar cycle (52%). Thus HSSWs are more frequent at the end of solar cycles, while the magnetospheric electric field (EM) instead shows dominant features during the upward phase of odd cycles and the downward phase of even cycles. Therefore, the stability of the inner magnetosphere is more significant during the decline of solar cycles.