New breakthroughs in grid-connected technology promote large-scale development of photovoltaic power in China

status quo

China is the world's largest producer of photovoltaic modules. Although the photovoltaic modules it produces are mainly exported abroad, the issue of photovoltaic grid connection has become the focus of recent market discussions. In 2009, China introduced a series of policies and subsidy programs for the development of the photovoltaic industry, including open bidding requirements for photovoltaic plant development, the Solar Roof Program, the Golden Sun Program, etc. These new regulations are all aimed at better developing large-scale photovoltaic plants and urban photovoltaic roof systems.

China sets renewable energy targets

The Chinese government recognizes that if it wants to achieve its renewable energy goals, it must solve the grid connection problem. Both China's Renewable Energy Law and the Medium- and Long-Term Development Plan for Renewable Energy clearly list China's solar energy development target of 20 GW by 2020. In order to promote the development of renewable energy, the Chinese government has begun to introduce new regulations, including expanding renewable energy grid access regulations; developing advanced technologies such as smart grids; establishing annual renewable energy consumption target benchmarks and related implementation plans; and establishing a government fund to support the research and development of renewable energy technologies.

Perfect time

China is currently planning to vigorously develop solar energy and other renewable energy sources, especially the existing grid-connected solutions have further accelerated the networking and consumption of renewable energy. AMSC's new grid-connected technology can solve several major problems currently facing China's power grid, such as frequency and voltage deviations caused by the imbalance between energy demand and generation.

Modern, reliable grid-connected solutions are completely different from the traditional equipment deployed in China and other countries. The following will further introduce the modern robust grid-connected solution SolarTie™ grid-connected technology system launched by American Superconductor. Most inverters currently used in China are single machines with limited commercial and industrial applications. For large-scale photovoltaic power plants, similar equipment lacks the required technical characteristics and detailed specifications. These types of inverters are generally installed indoors, lack robustness, and cannot ensure that renewable energy is not disconnected from the grid when required to support voltage and reactive power, and cannot support the grid or improve the stability of the grid. While photovoltaic plant owners face losses, users may face grid quality problems or power outages. In addition, owners may face fines for not transmitting power to the grid or not transmitting enough contracted power.

China has announced its renewable energy goals and grid connection regulations are being updated. We are seeing newer and more advanced technologies coming to the market. Chinese authorities have released provincial grid connection technical specifications for photovoltaic power plants, which include detailed provisions for power control, power factor range and voltage regulation, including requirements for dynamic reactive power compensation in the event of system disturbances and sufficient capacity to withstand grid fluctuations such as low voltage ride-through and frequency disturbances. The threat to grid stability posed by large-scale renewable energy power plants has been a major factor hindering the development of renewable energy, so these grid connection specifications are important to plan. Solutions such as AMSC's SolarTie are robust enough to meet various grid connection standards.

What is the most advanced technology?

The grid connection of renewable energy has been fully and correctly interpreted in the grid connection standards, which serves as a reference for choosing which equipment to install and which control system to use. Grid management support, reactive power compensation and stable grid connection are also requirements of power companies for solar power plants. In addition, large-scale solar power plant developers must meet the grid connection requirements of power companies and also consider balancing electricity to achieve the most economical cost.

From an operational perspective, solar plants that can actively support the grid during disturbances are the best choice. When disturbances occur, these solar plants can help the grid recover and stay connected when it is needed most. Such an approach requires a dynamic reactive power compensation solution, such as AMSC’s D-VAR® system. Modern models of D-VAR are easy to configure, designed for power plants, have balanced power factors, react quickly, and actively support the grid during sudden faults such as sags, surges, frequency shifts, and transient high and low voltage conditions.

The most advanced solutions worldwide use inverters and reactive components to provide precise regulation at the point of connection using a "smart grid" interface. Reactive/active power distribution and additional control can manage the attached switching capacitors or controllers and, if necessary, apply voltage regulation to a wide grid.

Market Status

AMSC is the company that provides the most renewable energy grid-connected solutions in the world. 10% of the world's wind power plants are supported by AMSC's grid-connected solutions. More than 70 wind farms around the world are equipped with AMSC's D-VAR solutions to meet local grid-connected requirements.