March 20, 2023, China Power Construction Association "the second power construction industry Digital Economy Forum" was held in Xiamen. More than 1500 guests from the power, energy and Internet fields attended the event. Prof. Zheng Guilin, PhD Supervisor of School of Electrical Engineering and Automation, Wuhan University and Chairman of Suntrans™, as a special guest, shared Suntrans™ 's innovative "overall flexible intelligent distribution system" technology, as well as solutions for constructing scenarios in electricity digitization, urban digital carbon reduction and virtual power plant. The length limited summary is as follows:

The synergistic development of digitization and green is the inherent demand of high-quality development. The "two-carbon" goal is to achieve carbon peak by 2030 and carbon neutrality by 2060; The 14th Five-Year Plan and the 2035 Vision Target Outline call for "accelerating digital development" and "promoting green development". We can say that we will not only achieve the dual-carbon goal, but also complete the construction of a digital China.

Promoting energy conservation and carbon reduction is an important scene of current digitalization. The path of carbon neutrality includes: the first step, greatly saving energy and improving energy efficiency; The second step is to increase the consumption of local or external green energy by a large proportion; Third, carbon capture, storage and utilization; The fourth step, carbon compensation, carbon trading (to achieve neutrality). Carbon trading needs to meet measurable, reportable and Verifiable (MRV) requirements, which are also the technical standards agreed upon in the Bali Roadmap;

The construction of virtual power plant has become an important and urgent task at present: to build a virtual power plant with "larger load and larger energy storage", which can simultaneously meet the high efficiency of energy utilization, high proportion of green electricity consumption and digital power trading, so it is of great significance.

Our country is big power grid as the leading energy supply system. The grid is called the "supply side" and the user side is called the "demand side". In order to ensure the stability and safety of this system, the random consumption bottleneck of green energy connected to the grid is about 10%. Since the recent 40 years of rapid development of industrialization and urbanization in our country, the second and third industries in the city scale are highly intensive, a large number of urban buildings do not have the scale development of local green electricity conditions, the energy consumption is growing continuously, the external green electricity consumption ratio is difficult to increase, the power system capacity expansion demand is always there, and the power intelligent regulation technology urgently needs a breakthrough.

Suntrans innovative research and development of the "overall flexible intelligent distribution system", to achieve a breakthrough from intelligent power regulation from technology to system!

An innovation: "AC zero crossing no arc intelligent relay protection switch" technology breakthrough.It is the first time in 130 years since Westinghouse and Tesla commercialized alternating current (AC). Howard Mitchell, former president of the International Institute of Electrical and Electronics Engineers (IEEE), praised: "This is an innovative technology that changes the standard of electricity use in the world, very significant!"

One product system: no arc intelligent load controller, CQC compulsory certification of power equipment.At present, a full series of demand-side products have been formed, featuring:

●The fastest 22 times/second switch, mechanical switch times up to more than 1 million times (compared with the ordinary switch 5 thousand times), fast speed, long service life;

● No Arc (arc-less) when connected and broken, equipment safety to the system no impact, harmonics and other problems, put an end to electrical fire;

● Switch embedded edge calculation, the access equipment to achieve measurement, protection, control and programmable controller functions; Highly integrated, the volume is only 1/10 of similar equipment;

● With relay protection function, realize "busbar wiring", wiring lightweight, safe and convenient, save materials and time limit;

A network system: devices are connected on and off and powered on to create a "bootstrap" electric Internet of Things.

● All devices have IP addresses and upload encrypted data through SDK. The Internet of everything can be realized in the cloud (public or private cloud).

● Access to high-precision sensors, multi-parameter detectors and even other iot devices enables the network to be detectable, judgable and executable;

● The "information island" is eliminated, and information interconnection, active fire fighting, active carbon reduction, and "three possible" (MRV) of carbon emission data for various energy-using equipment of "water-electricity-gas-heat-cold" are realized.

An intelligent algorithm: PDWC algorithm suitable for energy management and control, to achieve accurate closed-loop control.It corrects the problems of large deviation and slow feedback of traditional PID algorithm, and enables closed-loop control of multi-objective, multi-task stable operation and active optimization in complex energy-using scenarios.

The core part of the system has no electronic equipment, which is different from the usual weak current intelligence, so it is also known as "strong current intelligence" in the industry.

In addition, energy storage, intelligent demand-side response and local consumption of green electricity are important manifestations of the capability of digital intelligent power system:

[electromagnetic coupling steam generator] heat conversion efficiency up to 98%, 50 seconds to generate steam, on and off precise control, can be through the valley electric heat storage (hot water energy storage) and artificial intelligence demand side adjustment, is an efficient electric energy replacement equipment.

[Power uninterruptible power supply] single-phase power UPS switching interval 18 milliseconds, three-phase power UPS switching interval 35-45 milliseconds, non-inductive switching; (Billions of chemical batteries can be eliminated every year in the communications industry);

[Dual-mode non-inductive switching absorption photovoltaic] photovoltaic power generation is not connected to the grid, local consumption of green electricity is preferred, when the output is insufficient, the system automatically switches to the mains (within 40 milliseconds), that is, quickly and no impact on the power grid and equipment, is a flexible non-inductive switching. Even if the rainy day can still run, the absorption rate of nearly 100%, economic benefits than green electricity grid-connected mode more than double.

[Ultra-efficient central air conditioning room] Based on the high-performance controller and cloud platform, the algorithm intelligent intermittent operation (second start and stop), dynamic optimization of the unit, the overall EER of the room stable above 5.5 ultra-efficient standard, realize unattended;

[Multi-parameter integrated sensing system] Sensor integrates radar, infrared induction, smoke, combustible gas, light illumination, temperature and humidity, air pressure, formaldehyde, toxic gas, pollution particles PM10\PM2.5, building posture, vibration state and other 17 sensing modes.

[From BIM to Digital Twin Network] This system is composed of two parts: physical power network and virtual Internet of things. Two-way data feedback, combined with lightweight BIM, realizes the "digital twin network" with full life cycle and real-time two-way interaction.

The power Internet of Things meets the power security and realizes the functions of intelligent power control and dispatch, digital decision and display, and digital tariff settlement, which are essential capabilities for virtual power plants.

Virtual power plant is the most economical and environmentally friendly way to solve the problem of power shortage.At present, the relationship between supply and demand of western and eastern electric power is tight, and the difference between peak and valley of electric power is becoming increasingly prominent. The annual peak load of more than 95% of the total load is less than 50 hours. According to the calculation of State Grid, it needs 400 billion yuan of investment to achieve peak trimming and valley filling of power system through thermal power plants to meet 5% peak load. However, it only costs 50 to 60 billion yuan to invest in the construction, operation and incentive of virtual power plants.

Virtual power plant is a kind of energy coordination control system.One key to the failure to implement on a large scale in the past was the immaturity of "demand side" technology. Now, the large-scale installation of intelligent power load controller is used to build the power Internet of Things system. During operation, important loads are selectively guaranteed, part of secondary loads are removed, peak cutting and valley filling are implemented, and digital tariff settlement is implemented, so as to realize the "demand-side virtual power plant" (rather than the supply-side virtual power plant) and ensure the smooth operation of the power grid.Features:

●Real-time scheduling, anytime and anywhere in the protection of important load under the premise of cutting out the less important load;

● Ensure production, accurately control residential demand for electricity, and ensure production demand;

● Green electricity consumption: dual mode power supply, scale consumption of local green electricity;

● Digital control: limit regional unit energy consumption index, with physical power consumption control to ensure "effective energy saving";

● Digital transaction: the combination of "three functions" and incentive mechanism;

● Simple and easy: the cost is usually 1/8 of that of a physical power plant.

[Real case of virtual power plant] Since 2014, Suntrans™ has continued to implement power distribution transformation for newly built and existing apartment buildings in Wuhan University. At present, more than 100,000 arc-free intelligent load controllers have been invested to control tens of thousands of student apartments, and an "electricity management information system for student apartments" has been built to realize intelligent control.

The automatic load identification system eliminates illegal electrical appliances to ensure the safety of campus electricity consumption and greatly improves the power management level of student apartments. Through intelligent management and control, the property management team of campus apartments is changed from 400 people to 1 outsourcing person, realizing the maximum cost reduction in operation and maintenance. The Internet of Things system has changed students' energy consumption habits, and the energy saving rate has reached more than 50% compared with the same period last year. (Hubei Daily, Wuhan Energy Conservation Supervision Center has reported) Also due to the lightweight characteristics of  Suntrans™ flexible intelligent power distribution system project, solved the "wiring bridge and the dilemma of cultural relic repair", the century-old cultural relic building "Ying Yuan" on the campus was successfully renovated and renovated as new, and won the national "Cultural Relic Repair Award" in 2017.

The system can solve the problem of campus power safety control and successfully embed the capability of virtual power plant. When the campus is short of power and needs to limit electricity, the system intelligently shuts down the air conditioning (about 1.2 kW) in each dormitory, and the entire 12 MW electricity is transferred for the teaching experiment building. It is equivalent to "storing" 12 megawatts (a quarter of the school's electricity consumption) in the student apartment, realizing the function of demand-side virtual power plant, and making contributions to urban digitalization and carbon peak.

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