Не бывает, НО Self Powered Hub может проснуться в плохом настроении и объявить себя Bus-Powered Hub-ом :-) Self-powered hubs may experience loss of power. This may be the result of disconnecting the power cord or
exhausting the battery. Under these conditions, the hub may force a re-enumeration of itself as a bus-powered
hub. This requires the hub to implement port power switching on all external ports. When power is lost, the hub
must ensure that upstream current does not exceed low-power. All the rules of a bus-powered hub then apply.