Biomass gasification is a process of converting biomass to a combustible gas suitable for use in boilers, engines and turbines to produce combined cooling, heat and power. This paper presents a detailed model of a biomass gasification system and designs a multigeneration energy system which uses the biomass gasification process for generating combined cooling, heat and electricity. Energy and exergy analyses are first applied to evaluate the performance of the designed system. Next, minimizing total cost rate and maximizing exergy efficiency of the system are considered as two objective functions and a multiobjective optimization approach based on differential evolution algorithm and local unimodal sampling technique is developed to calculate the optimal values of the multigeneration system parameters. A parametric study is then carried out and Pareto front curve is used to determine the trend of objective functions and assess the performance of the system. Furthermore, a sensitivity analysis is employed to evaluate effects of design parameters on the objective functions. Simulation results are compared with two other multiobjective optimization algorithms and effectiveness of the proposed method is verified using various performance indicators.

生物质气化是将生物质转化为可燃气体的过程，适用于锅炉，发动机和涡轮机，以产生冷却，热能和动力的组合。本文介绍了生物质气化系统的详细模型，并设计了一个多代能源系统，该系统利用生物质气化过程来产生冷却，热和电的组合。能量和火用分析首先用于评估设计系统的性能。接下来，以最小化总成本率和最大化系统的火用效率为两个目标函数，提出了一种基于差分进化算法和局部单峰采样技术的多目标优化方法，以计算多代系统参数的最优值。然后进行参数研究，并使用帕累托曲线来确定目标函数的趋势并评估系统的性能。此外，采用敏感性分析来评估设计参数对目标函数的影响。仿真结果与其他两种多目标优化算法进行了比较，并使用各种性能指标验证了该方法的有效性。