Вы можете использовать API:
Declare Function SetSuspendState Lib "PowrProf" (ByVal Hibernate As Integer, ByVal ForceCritical As Integer, ByVal DisableWakeEvent As Integer) As Integer
SetSuspendState(0, 0, 0) 'Sleep without forcing and ?no? wake events
SetSuspendState(1, 0, 0) 'Hibernate without forcing and ?no? wake events
Установите Hibernate на 1 (True) на Hibernate или 0 (False) на Sleep.
См. API здесь .