Sgt Lee Valentine, along with two other people were stabbed in the attack at Victoria station in Manchester on New Year's Eve, following which fellow officers disarmed a man, who has been detained under the Mental Health Act.
Chief Constable Paul Crowther said they had prevented others "being hurt".
Sgt Valentine, who has asked media not to use his picture, had been the first on the scene of the attack, a British Transport Police spokeswoman said.
The officer said the positive public response to his team's action "really does mean the world to us".
"When we saw the man wielding a knife, instinct took over and we were able to... successfully detain the male."
Sgt Valentine was treated in hospital for knife wounds to his shoulder but was later discharged. The injured man and woman, who are both in their 50s, remain in hospital.
The family of the 25-year-old suspect, who was detained under the Mental Health Act on Tuesday, have said their "thoughts and prayers" are with the three victims.
A Greater Manchester Police spokesman said a "counter-terrorism investigation remains ongoing" and officers continue to search the suspect's home in Cheetham Hill.
Speaking through a solicitor, the suspect's family said they were also grateful for "the comfort given to those affected by fellow Mancunians and citizens".
