流量制御機器の外乱モデルとIMCによるセンサレス圧力外乱抑制

抄録

Mass Flow Controllers (MFCs) using thermal flow sensors are widely accepted to control gas flow in the semi-conductor industry. Recently, gas flow stability and repeatability are important factors affecting device performance and yield in highly integrated semiconductor devices. Especially, Compensation of pressure disturbances at upstream of MFC is a critical issue to maintain flow stability. Therefore, pressure insensitive MFCs have been developed to overcome flow fluctuations compensation by a pressure sensor. This paper proposes a robust control method without any pressure sensor. A mathematical model is developed for MFCs to design a robust PID controller using Internal Model Control (IMC) and disturbance attenuation involving complementary pressure sensitivity. In this paper, experimental validation is performed to show the effectiveness of the proposed method.