本文针对多功能变制冷剂流量（MFVRF）系统在不同运行模式下提出了极值搜索控制（ESC）方案，以在满足热舒适性的前提下最大限度地提高效率。极值搜索控制是一种无模型控制方法，它可以搜索未知的、时变的最优输入，从而在不需要对象模型的情况下优化给定的性能指标。本研究考虑了五种运行模式，包括仅冷却、仅加热、冷却为主、加热为主和热回收模式。在所有情况下，区域温度设定值都是通过控制各自的IDU风扇转速来实现的，所需的反馈是压缩机电机、ODU冷凝器风扇和IDU蒸发器风扇的总功耗。 对于不同的运行模式，ESC输入被选择为压缩机吸入压力设定点、ODU风扇转速、旁通流量阀开度、IDU和ODU的过热设定点的不同组合。为了评估所提出的控制策略，针对所考虑的多功能VRF系统，建立了基于Modelica的动态仿真模型。仿真结果证明了ESC以无模型方式实现最佳运行的能力，以及节能的潜力。引用:2016年冬季会议，佛罗里达州奥兰多，会议论文

This paper proposes extremum seeking control (ESC) schemes for Multi-functional Variable Refrigerant Flow (MFVRF) system under different operational modes, in order to maximize the efficiency provided the satisfaction of thermal comfort. Extremum seeking control is a model-free control method, which can search for unknown and time-varying optimum input(s) that can optimize a given performance index without the need for plant model. There are five operational modes considered in this study, including Cooling Only, Heating Only, Cooling Dominated, Heating Dominated, and Heat Recovery mode. For all cases, the zone temperature setpoint is achieved by controlling the respective IDU fan speed, and the feedback required is the total power consumption of the compressor motor, ODU condenser fan and IDU evaporator fans. For different operational modes, the ESC inputs are chosen to be different combinations of compressor suction pressure setpoint, ODU fan speed, bypass flow valve opening, superheat setpoints for IDU's and ODU. To evaluate the proposed control strategy, a Modelica based dynamic simulation model is developed for the multi-functional VRF system considered. Simulation results demonstrate the capability for the ESC to achieve the optimal operation in model-free fashion, as well as the potential for energy saving.