Yes, the term is equating. According to CB’s SAT white papers, each test is equated, using common test populations, common test sections, experimental sections, etc., to, as effectively as statistically possible, assign students of equal performance an equal score, regardless of the test difficulty or the number of questions correct/incorrect.
However, I find it interesting that there are four answer keys for the same test date and a single raw score conversion. They make the statement that “ There is no advantage or disadvantage in taking any particular test form.”
I find this concerning, as it’s at odds with CB’s story that equating accounts for test difference across SAT dates as tests may differ in difficulty because it’s impossible to ensure tests are the same. If so, how can they simply state that multiple PSAT tests on the same date are the same?
In summery, from the attached document, you appear to be correct that there are four different tests, all scored and equated the same, with an assumption they are all the same difficulty. A cynic would say they don’t treat the PSAT as seriously as the SAT. This is statistically troubling.