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• Access Plan Product Design Guide

Access Plan Product Design Guide

This section provides you with operation suggestions of access plan design in Greenwich and related references. Read this section to get acquainted with the design procedures and regulations.

Design References

• Requirement specifications of the access plan product
• Regulations for wind farm access to electric system GBT 19963-2011
• Technical requirements of distributed power source grid connection GBT 33593-2017
• Technical regulations to access distributed power source into power distribution network NBT 32015-2013
• Technical code to access distributed power source into power distribution network QGDW 11147-2013
• No. 1781 document from State Grid Corporation of China
• Eighteen measures against major power grid accidents

Product Application Scope

The access plan product V1.0 is mainly applied in the access plan operation in distributed wind farm. The limited power operation is supported but the access plan in centralized wind farm is not.

Operation Procedure and Related Suggestions

For main operation steps in Greenwich access plan product V1.0, refer to the user guide in Greenwich documents.

Editing Electric Single-Line Graph

Electric single-line graph is the input of wind farm electric design. Before substation siting, substation design, and power line design, finish the electric single-line graph modification.

A complete wind farm electric single-line graph is consisted of one of the typical structures listed below:

• Turbine——Turbine transformer——Self-built substation

  

• Turbine——Turbine transformer——Self-built substation——Grid-connected substation

  

• Turbine——Turbine transformer——Self-built substation

  Turbine——Turbine transformer——Self-built substation

  

• Turbine——Turbine transformer——Self-built substation——Grid-connected substation

  Turbine——Turbine transformer——Self-built substation——Grid-connected substation

  

• Turbine——Turbine transformer——Self-built substation——|—Grid-connected substation

  Turbine——Turbine transformer——Self-built substation——|

  

• Turbine——Turbine transformer——Self-built substation——|—Self-built substation

  Turbine——Turbine transformer——Self-built substation——|

  

• Turbine——Turbine transformer——Self-built substation——|—Self-built substation——Grid-connected substation

  Turbine——Turbine transformer——Self-built substation——|

  

The typical structures listed above are only for your reference and you can modify them based on the actual project situation.

Matching Electric Single-Line Graph

After you modify the electric single-line graph, perform the substation siting operation. If there is any existing substation object, match the electric single-line graph.

The substation object is classified into three categories: turbine transformer, self-built substation, and grid-connected substation. No match is needed for turbine transformers.

• To match self-built substation, ensure the ingoing and outgoing voltage levels are consistent.

• To match grid-connected substation, ensure the ingoing voltage level is the same as that in the access point and the accessed capacity does not exceed the accessible capacity of each access point bay and total accessible capacity of substation.

  Note

  A substation can be matched for only once.

Creating Grid-Connected Substation

Select access type when you create a grid-connected substation. Different access types are corresponding to different input situations and judgement regulations.

• Access substation

The Substation capacity and Accessed new energy power capacity options are mandatory and others are optional. Based on the information you input, the system judges the accessible capacity of this substation. While judging the capacity, the priority of data input is Minimum load of substation > Average load of substation > Substation capacity * 20%. Take minimum load as an example, the accessible capacity of grid-connected substation = Minimum load - Accessed new energy power capacity.

Grid-connected device in/out of tower (optimized version for 10 kV switching station) defines whether the self-built substation connected with this grid-connected substation uses grid-connected device in/out of tower. The two types of substations are only applicable for 10 kV switching station because the devices have been optimized. Select one of them according to the local policy because the acceptance degree of grid in different regions differs.

• Access switching room

The Switching room capacity field is mandatory. The judgement rule of capacity is that total accessible capacity is equal to switching room capacity. Whether the power quality of user is higher than national standard refers to whether the original power quality required by user is higher than national standard. The selection of this option impacts the final accessibility judgement result.

• T-access circuit

Line category and Transportable capacity are mandatory options. The judgement rule of capacity is that total accessible capacity is equal to power line transportable capacity. No. of existing T-access circuit indicates whether the target circuit has connected other T-access circuit and how the quantity is. Your input here impacts the final accessibility judgement result.

Access Plan Calculation

1. Grid-connected substation

Only grid-connected substations that pass the access judgement are listed here.

1. Calculation scope.

The scope should include turbine and grid-connected substation. You can set up inward and outward buffer.

1. Calculation setup

When the total turbine capacity exceeds the total capacity of accessible grid-connected substations (that it, some turbine locations might be abandoned), choose to limit power of turbine to access more turbines. To calculate with limited power, ensure the WTG group owns the power production time series file.

1. Result display

After the calculation is completed, the results of every access point in different grid-connected substations of WTG group are generated, and the electric single-line graph is automatically generated (If there has already been an existing one, it is overwritten by the newly generated one) and matched with grid-connected substations. Double-click the Access related economics tab to check the economic result details.