Yang Chen, Subway Technician
Yang Chen, a talented subway power supply technician, has a knack for solving problems in Beijing's subway, admitting that a “transfer to the automation squad feels like a fish set free in water.”
For each device, there are ten sets of fixed values, which can be switched after being configured. Each fixed value is further divided into sub-values to be realised by the protection device, including those for input and output...” Yang pointed at the data displayed on the LCD screen of relay protection device for the analog substation and explained their significance to the green hands around him, as he stood on a ladder in the studio named after him.
Yang Chen is the deputy manager of the Overhaul Project Department, Beijing Subway Power Supply Branch. Habitually earnest and reticent, thirsty for knowledge, he is prone to speaking about subway renovation and technological innovation. In April 2007, he was appointed leader of the automation squad at only 25. His squad was awarded the title of Outstanding Squad in Economic and Technological Innovation by Beijing Mass Transit Railway Operation Corporation Limited in 2007 and “Beijing Youth Civilization Unit” in 2009.
Yang Chen himself has constantly improved his expertise and repeatedly made remarkable achievements in work by sticking to innovation. He has been awarded honours and awards, including Young Technical Expert of Beijing, Pacesetter of Economic and Technological Innovation in Beijing, Outstanding CPC Member, and Star of Power Supply. In recent years, when the Power Supply Branch underwent project-based department reform, Yang Chen shouldered the task of upgrading the power supply. For six years, he led his innovation studio in continued exploration into upgrade projects and encouraged technological research and development, offering technical support for safer and reliable power supply.
A Technical Star
The Overhaul Project Department of Beijing Subway Power Supply Branch is trusted with power supply facility engineering and renovation, overhaul, upgrade and emergency repairs. “Each of the tasks is a hard nut to crack,” says Yang Chen. Electricity is an inevitable part of his work, whether in upgrading 10 kilovolts and 750 volts of main equipment or transformation of smaller auxiliary equipment. Since the life of power lines ranges from 5 to 20 years, his department is required to rebuild them after reviewing their life cycles. Now, transformation projects undertaken by Yang Chen and his team exceed a dozen each year.
The Overhaul Project Department is a key part of the Power Supply Branch. It pools the company's power elite, of which Yang Chen stands out. However, before he entered the subway's technical school, he had little to no understanding of the subway's electrical network.
In the entrance examination for senior high schools, he failed by three points. As luck would have it, he became a student at the Beijing Metro School. Yang Chen said that back then the subway was nothing more than a means of transport for him. After two years in school, he took a liking to relay protection. His reasons were simple. He had considered himself a technical enthusiast and would choose nothing but work with the highest technical content. Power supply equipment can be categorised as primary and secondary. The former is comprised of switches, cables and transformers for power supply, while the latter can be defined as sophisticated devices for controlling and protecting the former. The latter is more technology-intensive, deemed by Yang Chen as more reflective of technical advances. Among secondary power equipment, relay protection is most representative, used to control and protect switches in primary equipment and to achieve automated changes in the switch status.
In his third year at school, Yang Chen was sent to a subway station for an internship. As he had learnt line drawings in advance, he had no difficulty in “effectively applying” classroom learning to practical operations. However, the electric cable map he learnt in the classroom was just a prototype, and in practice is different for each station. So he compared the two and pestered his squad leader whenever he found an inconsistency. “Back then, my notebook was covered with drawings. In electrical engineering, you must be ready to ask questions, because the textbooks are out of date.”
After one year of internship, Yang Chen became proficient with the cable map. The communication between him and Hong the then squad leader of Wukesong Station was turned to two-way interaction. Many discoveries made by Yang Chen also broadened Hong's vision and thinking.
In September 2000, Yang Chen was assigned to the upper floor of Fuxingmen Station on Subway Line 2 as an attendant, responsible for monitoring substation equipment. Reporting problems, switch operations, patrolling and cleaning became his daily routine. Fortunately, for the post on duty, he witnessed thorough cleaning of the 750volt device twice, and the experience became a great learning opportunity.
“I became so ecstatic because eventually I managed to operate those devices. In the evening of thorough cleaning, I finished my daily routine and promptly began studying the electric map against the actual equipment. The two-dimensional symbols on the map made better sense and became entrenched in my mind. That was a qualitative leap.” Yang Chen recalled.
Keeping Pace with the Times
Yang Chen is among the first of the “Post-1980s” generation to be exposed to computers and networks. He became spellbound by computers when he first laid eyes on them. His mother was very supportive and bought him a Dos-based computer. What now seems to be a primitive computer acquainted Yang Chen with programming and introduced him to automation.
Yang Chen explains that the principle of relay protection and that of automation are of the same strain. Relay protection is aimed at
“Innovation should not be attributed to me alone but to my team. It is a great honour to have the innovation studio named after me, but I am also keen of responsibility.”
controlling main equipment, while automation is aimed at remote integrated control combined with computer technology. He even admitted that “transfer to the automation squad feels like a fish set free in water.”
Before 2001, the subway's automation involved only power supply for remote control of the 750V and 10kv equipment for straight line subways, as well as real-time voltage and observed current data. Soon after his transfer to the automation squad, Subway Line 13 and the Metro Batong Line were successively commissioned, ushering in a stage of marked development for the subway's automation. Meanwhile, Yang Chen ushered in a critical period of his learning career.
At that time, automation equipment for power monitoring introduced by Beijing Subway was operated via a computer network. Yang Chen was interested in the new equipment, and had a theoretical foundation, so an easy start came to him naturally. However, the equipment manufacturer kept core technologies confidential, making it the only party capable of solutions in case of a malfunction. This resulted in a waste of subway operating time and costs.
Failure rate of new equipment in the first five years was very low. In 2007, soon after five years of stable operation, various failures emerged. That year happened to be the year Yang Chen was to be appointed leader of the automation squad, and the task of seeking solutions fell to him. Recalling that period, he said, “Faced with this grim reality, we had no way out, except for innovative transformation!”
Back then, the IO system for communication control frequently broke down, obstructing real-time data feedback. The subway became a “blind man crossing the river.” Yang Chen drew on his prowess in computer technology, changed the media for IO program copying from floppy disk to CD-ROM, and designed the program for the automatic operation and installation of the program. This way, he managed to shorten the system recovery time from two hours to a little more than ten minutes. His team did not stop at that. Based on successive experimentation, they upgraded the CD-ROM to a hard disk, in which the programme was pre-installed. After that, it became possible to install the program and restore equipment operation within five minutes after reaching the fault site. That was later heralded by Beijing's subway staff as a “time transfer method.” It constituted not only innovation in storage media, but also a great new leap in programming.
In order to shorten time for troubleshooting, Yang Chen divided the automation squad into several groups. The “technology gurus” were assigned to one group and those good at communicating with another. Thus, allocation of human resources was optimised and efficiency in repairs were heightened. In 2009, Yang Chen's team of 20-odd members witnessed its peak in troubleshooting. Specifically, they had to handle 1,400 failures for four subway lines in Beijing each year, an average of four each day.
Yang Chen continued expanding the depth and breadth of his knowledge during his work. He even made a point of teaching himself how to use computer network applications and PLC (programmable logic controller) technology. His efforts have culminated in his promotion to senior worker and technician, making him the youngest worker-turned technician of the Power Supply Branch. Meanwhile, he was appointed instructor, to help his fellow workers enhance their business competence. He made prominent contributions to the company in talent cultivation. Over the years, most of the members of the automation squad under his leadership have become the mainstay for operation and integrating maintenance for new subway lines.
Responsibility of Reform
In 2011, a large-scale network-based pattern gradually formed in the Beijing Subway. In this context, the Beijing Subway Power Supply Branch launched comprehensive reform for the department system. The originally separated operation and maintenance in power supply management gave way to integrated operation and maintenance, and equipment technology ushered in an era of full automation. The automation squad was dismissed and each subway line set up its own maintenance department. The original Maintenance Team was converted into the current Overhaul Project Department. Yang Chen stayed and became responsible for safety operation, core to the subway's mission.
In recent years, Beijing's Subway has launched projects of reconstruction. In 2012, Yang Chen was hired to manage a large reconstruction project for the first time. “It was the 10kv reconstruction project for Fuba Line. Reconstruction must
be conducted without interfering with its normal operation. Therefore, dismantling, reassembly, debugging and commissioning had to be finished at night-time when hours of operation ended. It was literally a race against time.” Yang Chen said that the external wiring for the relay protection device was complex with no mistakes allowed. His team rehearsed in advance, in which it broke the operation into seconds and formulated 11 plans for each station. “We couldn't afford any rework or error, so as to meet the schedule. We challenged ourselves and cracked the hard nut. The 16 members of the team learnt the operation by heart. Their cooperation turned the site construction into an assembly line.”
This year, Yang Chen's team is in charge of the transformation for the 750V equipment of “Fuba Line,” a direct power source for the locomotive and its failure which directly affect the locomotive. Difficulty in engineering increased. However, since its commencement last year, the large-scale reconstruction project has never been affected by any issues. Yang Chen concluded that its smooth progress is partly attributed to the successfully formulated and implemented plan based on experiences in 2012. It is also attributable to the analog substation built with obsolete drilling devices. Prominent effects of the analog substation have encouraged all the project departments to build analog substations of their own.
“Specialisation will be the path for our future development. The past six years happened to be an important period for business expansion of the Beijing Subway Power Supply Branch. From 2011 when I started managing renovation projects, my responsibilities have fundamentally changed. In reconstruction projects, there is no precedent to draw on. All that we learn from the books must be tested with practice,” Yang Chen said. “No matter how our business changes, our responsibility for ensuring a safe and reliable uninterrupted power supply will be constant. Safe operation and transformation projects are now contradictory and mutually restrictive. We have to conduct transformation while ensuring safety in operations to ensure success in both.
A Hero with Modesty
Yang Chen stressed that innovation should not be attributed to him alone but to his team. He said that it was a great honour to have the innovation studio named after him, but he was also keen of responsibility and pressure. He considered himself just an ordinary worker like the 16 members of his team. Each and every technological innovation and invention benefitting safe production sprung from worker's contributions bent on solving problems in power supply of the subway.
“The Innovation studio called for inventions from the whole company with positive feedback.” Yang Chen remarked earnestly, “Usually front-line workers have a lot of good ideas, but no channels for application. We now provide the channel. Humane and financial support are granted to good proposals.”
Yang Chen kept a low profile and assumed an earnest attitude toward work, consistent with his profession. Power supply professionals are experts behind the scenes. They are invisible to the people, but the results of their work are enjoyed. Power supply means a highrisk career, which entails that professionals be stable, rigorous and pragmatic. This is consistent with Beijing Subway's service. Yang Chen said that their invisibility meant normal operation of the subway and their appearance often indicated problems.
Thanks to the efforts of those heroes behind the scene, the innovative initiatives of Beijing Subway Power Supply Branch have achieved good results. Each project department has begun to establish its own innovative workstation. The subway network continued to expand. Meanwhile, regional rescue missions have achieved outstanding advantages, ensuring safety operations of subway lines.
Yang Chen recalled one glorious moment. “I am proud for being a staff member of Beijing Subway. I shoulder the glorious mission of the subway and invest my enthusiasm in constructing a ‘safe, humanoriented, efficient, economical, convenient and innovation-driven subway.' I contribute all my strength to the goal of building an outstanding provider of maintenance services for subway power supply.”
Yang Chen adjusting a device according to the drawing
Yang Chen (middle) illustrates operating principles to colleagues.