  This paper proposes a correction method, which corrects the actual compressor
performance in real operating conditions to the equivalent performance under
specified reference condition. The purpose is to make fair comparisons between
actual performance against design performance or reference maps under the same
operating conditions. Then the abnormal operating conditions or early failure
indications can be identified through condition monitoring, which helps to
avoid mandatory shutdown and reduces maintenance costs. The corrections are
based on an iterative scheme, which simultaneously correct the main performance
parameters known as the polytropic head, the gas power, and the polytropic
efficiency. The excellent performance of the method is demonstrated by
performing the corrections over real industrial measurements.
