长庆油田数字化建设的目的是提高生产自动化水平，降低员工的劳动强度。在增压站的数字化建设规范中，对于原油外输系统的一般性要求是能够根据缓冲罐液位对外输泵频率进行PID调节，以实现连续输油。但是在超低渗透油田，由于现场来油的间歇性及液位调节的滞后性，PID调节方式并没有体现出其平稳调节的效果。 本文针对超低渗透油田增压站外输系统控制方法进行优化研究。将缓冲罐液位在整个液位范围内分段，各分段采取不同的频率控制策略，使缓冲罐液位控制在相应分段的设定范围内，由于外输泵输出频率被设定在有限运行的几个频率点上，外输泵输出液量基本稳定。中间分段区间采用增量式PID调节输出频率，在输油平稳且没有外界干扰的情况下，通过增量PID算法控制外输泵频率，使缓冲罐液位稳定在中线附近。控制系统选用西门子S7-300系列，实现输油泵与缓冲罐液位的联动控制。组态采用北京三维力控组态软件，实现对生产数据的采集、显示、存储、报警等功能。 通过对数字化增压站分段PID控制系统实地测试，表明分段PID控制有利于增压站缓冲罐液位的稳定，能够满足超低渗透油田数字化增压站外输控制需求。另外，输油泵基本运行在低频阶段，也降低了外输流程的电能损耗。

Changqing oilfield digitalization construction of the purpose is to improve the level of production automation, reduce the labor intensity of workers. In the digital construction specification of booster station, general requirements for crude oil transmission system is able to outside pumps frequency according to the buffer tank liquid level PID adjustment, in order to realize the continuous oil. But in low permeable oil fields, because of the oil field to lag of intermittent and liquid level control, PID regulation does not reflect its smooth adjustment effect. Low permeable oil fields, this paper booster station transmission system control method is optimized. The buffer tank liquid level within the scope of the whole level section, section take different frequency control strategy, make the buffer tank liquid level control within the scope of the corresponding block set, due to the limited transmission pump output frequency is set in the running of several frequency point, transmission pump fluid output basically stable. In each of the piecewise interval by incremental PID adjust output frequency, the oil smoothly and without outside interference, through incremental PID algorithm to control the pumps, the buffer tank liquid level stable in a reasonable range. Siemens S7-300 series is used in the control system, realize the oil transfer pump and the linkage of the buffer tank liquid level control. Configuration by Beijing sunway configuration software, the implementation of production data acquisition, display, storage, alarm, etc. Digital booster station piecewise PID control system based on field tests, show that the piecewise PID control is beneficial to the stability of the booster station buffer tank liquid level, can satisfy the ultra low permeability oilfield digitization booster station transmission control requirements. And as a result of oil transfer pump basic running in low frequency phase, make the whole transmission process in terms of power loss has been reduced.