Abstract: To resolve the problem of unrealistic operation plans developed at the early stage for centrifugal compressors, this study was conducted to predict the performance of centrifugal compressors. For the purpose of error correction and taking a centrifugal compressor unit of a specific compressor station as an example, we transformed the performance curve of the compressor unit using a multi-transformation algorithm. Subsequently, the performance curve as processed through similarity transformation was fitted based on the method of least-square surface fitting. Considering the deterioration of the compressor unit, an error correction model of the compressor performance parameters was obtained through least-squares one-element fitting. A comparative analysis was further performed between the model and multiple sets of historical data obtained under different working conditions. The results showed that the relative error of the shaft power and the pressure ratio prediction obtained from the error correction model was within 3% when compared to the actual measurement values. This finding validates the reliability of the proposed error correction model. It further provides realistic basic production data for developing a proper operating plan for a compressor unit.

Key words: centrifugal compressor, Error correction, Least square method, Performance prediction