When there is error in estimating the production delay time, inventory level will drift from the target in the “automatic pipeline, inventory and order based production control system”(APIOBPCS) model. By adding a PI control in the inventory feedback loop,a PI-APIOBPCS model was proposed, which could eliminate the inventory errors, but productivity and inventory levels fluctuated significantly. And by adding the PD controller in the order rate policy, a PID-APIOBPCS model was proposed, which can effectively eliminate the inventory drifts, and smooth the productivity and inventory levels, and reach the steady state quickly.

system dynamics, production control system, production time, inventory error

在生产控制模型APIOBPCS（automatic pipeline, inventory and order based production control system）中，当企业估计的生产时间与实际生产时间不符时，实际库存水平与目标库存水平之间存在一定的偏差。通过在库存反馈环中加入PI（proportional plus integral）控制机制，构建了PI-APIOBPCS系统。该系统能够有效地消除库存偏差，但会使生产率和库存水平波动扩大。通过在生产控制环节中加入PD（proportional plus derivative）控制机制，构建了PID-APIOBPCS系统，该系统不仅消除了由生产时间估计误差所造成的库存偏差，而且抑制了生产率和库存水平波动的扩大，可使生产控制系统较快到达平稳状态。

系统动力学, 生产控制系统, 生产时间, 库存偏差