1MRK00008-KB  DCS control system reliability improvement

0 Overview

1MRK00008-KB In the whole process of production, it is recommended to strengthen personnel safety management and technical training, optimize and improve equipment as much as possible, which is an important aspect of improving the reliability of power plants. For power plants, the reliability of power generation equipment is a comprehensive index, which mainly includes: unplanned outage times, equivalent availability coefficient, equivalent unplanned outage coefficient, output reduction times, utilization hours, etc. Through these indicators, a more comprehensive understanding of the safe and stable operation level of a power plant can be obtained.
In today’s increasingly tense power, how to improve the reliability of equipment has been paid more and more attention by each power plant. Based on his long-term experience in thermal control maintenance work in power plants, the author expounds how to improve the reliability of the whole DCS control system from the perspective of DCS control system selection, equipment installation, program design, debugging and acceptance, and technical training.

1, DCS control system reliability

1MRK00008-KB With the development of the national economy and the improvement of people’s quality of life, the relationship between the importance of electricity to the national economy and the improvement of people’s quality of life is getting closer and closer. Due to the particularity of power production, improving power reliability has become a social work under the enterprise goal of “grasping safety and emphasizing efficiency”. Only by giving full play to the enthusiasm and creativity of managers at all levels, relying on the progress of technology, and effectively mobilizing the initiative of all employees, can we improve the reliability of power generation equipment to do more detailed and more solid work, in order to achieve good performance.

For large power plants, the reliability of the control system is vital to the safety and reliability of the whole power plant. Around the 1970s, with the development of 4C technology and the improvement of single-unit parameters of thermal power plants, the control system has developed in the direction of decentralized function and centralized management, and its reliability has been greatly improved, and distributed control system (DCS) has been adopted in large power plants (stations) abroad. China also in the middle and late 1980s in the introduction of complete sets of generators on the application of DCS, up to now, the new unit in the control system selection are using a variety of mature DCS control system, the old unit with a large capacity also through the control system transformation, the basic use of DCS control system.
1MRK00008-KBWith the improvement of automation level, DCS control system (distributed control system) has gradually replaced conventional instruments, and its superiority has been accepted by the majority of operators. However, when the fault occurs, it will cause the device to stop and even accidents, so how to find and deal with various faults as early as possible is very important. The synthetic ammonia process of our company uses several sets of Zhejiang University Central control JX-300XDCS for control, which is stable and reliable. In view of some existing problems, according to years of maintenance experience, we have summarized a set of effective fault identification and treatment methods.

1, 1MRK00008-KBview the data of the monitoring screen

When the following situations occur, it indicates that the control system has a problem, should immediately notify the computer maintenance personnel to repair, while the operator to the scene for processing.

(1) Frequently changing data is unchanged for a long time, and several or all data are unchanged.

(2) In the control group screen, the manual automatically cannot be switched, or after manually entering the data, once confirmed, it is restored to the original data, and can not be modified.

(3) In the trend chart screen, several trends are unchanged as straight lines.

(4) In the monitoring screen, multiple data fluctuate greatly at the same time.