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由于功率器件容量的限制与系统可靠性要求的严苛,风电变流器一般采用变换器并联来提升容量和可靠性,控制上采用功率均分运行模式.风能的随机、波动特性使得变流器的负载功率波动很大,其平均负载功率低于额定功率的50％.变流器的运行效率与负载率相关,功率均分运行模式使并联变流器低载工况下的运行效率低下.该文提出一种提升并联变换器系统运行效率的自适应功率优化控制方法.基于单个变换器的效率曲线,采用穷举优化算法优化不同负载功率时各并联变换器的最优功率分配值.通过离线优化、在线查找方式提高波动功率下并联系统运行方式的优化速度.引入功率滞环控制,优化变换器的投切.该文比较3种运行模式下并联系统的运行效率,结果表明,提出的自适应功率优化控制可有效改善波动载荷下并联系统的运行效率.“,”For limited power rating of power devices and stricter reliability requirements,wind power converter usually adopts parallel configuration to extend its power capacity and improve its reliability.Parallel converters operate in power sharing mode.For the intermittent fluctuation characteristic of wind,converter's handling power varies largely,and its average load power is less than 50 percent of rated power.The operation efficiency of power converter depends on its load ratio.With conventional power sharing control,operation efficiency of parallel converters is low at light loads.An adaptive power optimal control for operation efficiency improvement of parallel wind power converters was proposed in this paper.Based on the efficiency curve of a single converter,the exhaustive optimization algorithm was adopted to calculate the optimal power distribution between parallel converters under different loads.The fast optimal control for parallel system under fluctuating power profile was achieved by off-line optimization and real-time application.The power hysteresis control was applied to optimize switching transient.The operation,efficiencies of parallel system under three different control modes were compared.The results demonstrate that the proposed adaptive power optimal control can improve operation efficiency of parallel system under fluctuating load.