The first grid-connected national standard in the wind power industry will be implemented

Guidance: The “Technical Regulations on Wind Farm Access to Power Systems”, the first national standard for grid integration in the wind power industry, was approved for release and will be implemented from June 1 this year. Since the drafting of this standard, it has been constantly controversial and has attracted much attention from the industry.

The “Technical Regulations on Wind Farm Access to Power Systems”, the first national standard for grid integration in the wind power industry, was approved for release and will be implemented on June 1 this year.

Since the drafting of this standard, it has been constantly controversial and has attracted much attention from the industry. As for the strictness of the national standard, will it lead to a reshuffle of the wind power industry? The most important thing is whether the idled turbines will be restarted and connected to the grid. At the same time, once the grid connection can enjoy the “Renewable Energy Law” The full protection of the acquisition framework, many issues, all point to this new standard has just been released.

The new national standard China’s wind power has doubled its capacity in the past six years. The current installed capacity has increased from 1.26 million kilowatts in 2005 to 62.73 million kilowatts in 2011, and the capacity has doubled 50 times. However, behind the soaring wind turbines, wind turbines of many wind farms have been “discarded” due to their inability to be integrated into the grid, creating hundreds of wind turbines in multiple wind farms that “sunshine”.

According to the “Renewable Energy Law” implemented in 2006, power grid companies are required to sign a grid-connected agreement with a renewable energy power generation enterprise that has obtained an administrative license or filed for registration in accordance with the law, and acquired the full amount of renewable energy within its grid coverage. The amount of electricity generated by the electricity generation project and the provision of Internet access for renewable energy generation.

However, in reality, the grid gives relevant conditions for the full-scale acquisition of wind power, namely, the “Technical Regulations for the Integration of Wind Farms into the Power Grid” and the “Depth Regulations for the Design Contents of the National Grid Wind Farm Access System,” which is implemented as an enterprise standard. Because this standard belongs to the corporate standard, it does not have a mandatory constraint at the national level. Therefore, the problem of grid connection has continued.

At present, the wind power grid connection has been used in the "Technical Regulations on Wind Farm Access to Power Systems" issued in 2005, which is an industry standard. This time, the grid-connected national standard is revised on this basis.

According to the relevant person in charge of the State Electricity Regulatory Commission, the new national standard was initiated in 2009 by the National Standardization Technical Committee of the Electricity Regulatory Commission under the supervision of the SERC. Then in July 2010, the standard consultation draft was completed and a review draft was formed in November of the same year. In April 2011, the National Standardization Technical Committee for Power Supervision passed the standard approval draft. Since then, the draft has been revised and submitted to the Electricity Regulatory Commission again.

Compared to the 2005 version of the standard and the draft of the draft, the new national standard has put forward more and more stringent standards for low-voltage ride-through, wind turbine reactive power compensation and access test projects.

If specifically for off-net, the new national standard puts forward the constraints of low-voltage ride-through and requires that when the voltage at the grid-connected point of the wind farm falls to 20% of the nominal voltage, the wind turbine in the wind farm should ensure that it will not run off the grid for 625 milliseconds continuous operation, especially It is required that the voltage of the wind farm connection point voltage can be restored to 90% of the nominal voltage within 2 seconds after the voltage drop occurs. The wind turbine unit in the wind farm should ensure continuous operation without network disconnection.

At the same time, for the developers of wind farms, the new standard also proposes that when the installed capacity of wind farms connected to the same grid point exceeds 40 megawatts, it is necessary to provide wind power plant access control system test reports to the power system dispatching agencies, accumulatively increasing the installed capacity. More than 40 megawatts, the test report needs to be resubmitted.

In other words, for a large-scale wind farm, the capacity change exceeds this capacity, and the grid-connected test will be conducted again. “The integration of wind power requires the joint efforts of all parties, and the State Grid must strengthen the construction of the power grid to improve the dispatching capacity of wind power. Wind power machine manufacturers must create grid-friendly wind turbines that are conducive to the safety of the power grid. The four-long-long-distance long-distance power transmission channel for the KV power grid and the State Grid has already been opened, which will fundamentally change the issue of solving the problem of wind power grid access.” The official responsible for Huarui Wind Power told reporters.

Passing through a number of standards in the new national standard, the low-voltage ride-through requirements that have the greatest impact on grid connection will most likely lead to a new round of corporate knockouts. According to the newspaper’s understanding, the current market price for renovation varies from tens of thousands to hundreds of thousands each, and the amount varies according to the unit model, manufacturing batch, and age. “At present, most of the wind turbines that have been put into operation do not have low-voltage ride-through capability,” Yang Kun, the chief engineer of the Electricity Regulatory Commission, said at the press conference on “Safety of Wind Power Supervision Report”, “Firstly, some wind farms are not in the order contract. It is clear that the unit must have low-voltage ride-through capability, and there are wranglings in the renovation costs, resulting in suspension of the transformation plan; second, some wind turbines are expensive to transform, companies are facing huge financial pressure, and some wind turbines are MW grades that were put into operation early. The following wind turbines are difficult to transform."

A wind power equipment supplier told the reporter, “The current problem is that many wind turbines that were previously connected to the grid did not have space reserved for reconstruction because of the design at the time. Therefore, many sun-burning units are likely to be scrapped and unable to be connected to the grid. Before the grid connection did not meet the requirements, it also faced the problem that it was unable to complete the transformation and huge transformation costs."

At the same time, he also stated that like some enterprises that entered the wind power industry very early in the past, thousands of units that did not have low-voltage crossings were produced in the early years, so that they could be converted to 100,000 yuan each, and 10,000 were 1 billion yuan. For companies in the wind power industry that are already in a recession, capital flows will be stretched, and they will even face the risk of closure.

In particular, some newly entering the wind power industry, the R&D of their units is relatively late, and the upgrade of their units is also provided by some of the top wind turbine manufacturers to provide technology upgrade programs, and the upgrade costs are also relatively expensive.

According to the latest data from the China Electricity Regulatory Commission, as of the end of August 2011, only 34 wind farms and 4.34 million kW wind turbines nationwide have completed the transformation of low-voltage ride-through capability.

Since the domestic wind turbines are mostly customized, the components of the same model of wind turbines are not the same. The “Interim Measures for Wind Turbine Grid Inspection and Management” implemented last year requires that only one wind turbine of the same type be tested. However, generators, converters, main control systems, pitch control systems and blades, etc., which change the technical parameters that affect grid connection performance, are considered as different models and need to be retested.

As a result, as of the end of September 2011, only 13 models of wind power equipment manufacturing companies across the country passed the low voltage ride through capability test and power characteristics test. In other words, of the hundreds of models currently in use, 90% of the crew are still waiting for "passing."

“At present, only the State Grid Research and Evaluation Center for Wind Power Grid Integration and Research of China Electric Power Research Institute can do the test. It takes about three months for a machine to test. We have been in the team for nearly six months. We haven’t yet.” The manufacturer of the entire wind turbine, who declined to be named, said.

An indisputable fact is that with the implementation of the wind power grid-connected national standard to be implemented soon, the overall preparation of the industry has entered a countdown.