The main physical principles of quasi-stationary plasma accelerators, which are capable to generate super high power plasma streams in long pulses are discussed. The description of QSPA type devices in use in recent experiments, as well as characteristics of the plasma flow in the main acceleration channel and plasma parameters achieved at the outlet of QSPA, are presented here too. Finally, some possibilities of such accelerator applications for fusion and results of their use in divertor plates modeling experiments are described.