Abstract: Scheme evaluation is one of the key links of product service system design.The rationality of evaluation results is very important for the development of enterprises.Based on the least sum of squares method,cloud-TOPSIS-grey correlation analysis model is constructed to evaluate the product service system scheme.Cloud model and relative preference relation were introduced to quantify discrete indexes to solve the problems of fuzziness and randomness in expert evaluation.The positive and negative ideal grey association coefficient matrices were determined by TOPSIS grey association analysis method,and the positive and negative ideal grey association coefficient matrices were established by integrating index weights and positive and negative ideal grey association coefficient matrices,taking into account the position proximity and shape similarity of corresponding geometric scheme sequence curves.The least sum of squares method was used to solve the grey correlation coefficient and determine the scheme ranking.Taking the project evaluation of tractor product service system in an agricultural equipment enterprise as an example,the science and feasibility of the proposed model were verified.

Key words: product service system, program evaluation, cloud model, TOPSIS grey association analysis