Abstract: The infections on solar array by small space-debris hypervelocity in space environment are summarized.It causes not only mechanical damage but also permanent sustained arc(PSA)to solar array.And it also makes threats to solar array life time and reliability.The research progress is introduced in detail in Japan,Europe and China.And the key method is both diagnose instantaneous plasma and measures the second discharge by plasma induced.The research of hypervelocity characteristic about space-debris impact on solar array is suggested in order to protect the satellite solar array.