The first solution

1、 Selection and configuration details of wind power full chain circuit breakers

 

1. High voltage side of the transformer box

Priority should be given to using vacuum circuit breakers, which are suitable for frequent operation scenarios of wind power. The rated voltage of the system should be matched, and the breaking capacity should cover the maximum short-circuit current. Overvoltage protection devices should be used to avoid equipment damage caused by overvoltage operation.
2. Low voltage side of the transformer box
Small capacity units should choose plastic shell circuit breakers, while large capacity units should choose universal circuit breakers. They should have three protection functions: overload long delay, short circuit short delay, and short circuit instantaneous, and be suitable for contact heat dissipation requirements under harmonic working conditions.
3. Grid side
Select grid connected circuit breakers that can withstand frequent switching, while also providing fast fault isolation and grid phase synchronization functions, to adapt to frequent start stop conditions caused by wind power fluctuations.


2、 Full scenario overcurrent protection configuration scheme

1. Fan body side
Configure overload protection and quick break protection, which act on signals or directly cut off the machine. At the same time, it is equipped with low/high voltage and low/high frequency protection, suitable for power grid fluctuation scenarios.
2. Box transformer side
High voltage side is equipped with plug-in full range fuses to achieve transformer overload and short circuit protection; The low-voltage side circuit breaker acts as an overcurrent protection from the fan outlet to the box transformer section, and is activated to trip.
3. Collecting line side
Each 35kV incoming line is equipped with microcomputer line protection, with three-stage phase to phase directional current protection, overload alarm function, no reclosing, and a small current line selection device.
4. Main transformer and booster station side
The main transformer is equipped with differential protection and backup overcurrent protection on the high and low voltage sides. The 35kV busbar is equipped with independent busbar protection, and the 330kV and above high voltage sides are equipped with dual sets of completely independent overcurrent protection to ensure zero fault rejection.


3、 Optimization points for adapting to special working conditions of wind power

 

All overcurrent protection components must meet the requirements of wide temperature operation from -40 ℃ to 70 ℃, have resistance to salt spray and dust, and be suitable for complex outdoor operating environments.
The protection device should be compatible with the harmonic working conditions of the wind power system to avoid overcurrent misoperation caused by harmonics. At the same time, it should be equipped with a current transformer with harmonic measurement capability to accurately capture fault currents.
Do you need me to compile a comparison table of wind power electrical protection configuration parameters that can be directly implemented for you? Convenient for you to quickly select and verify.

1、 Core Electrical System Design Proposal

1. Electrical connection scheme for the unit
The doubly fed unit can choose a Y – △ hybrid connection scheme, with a Y-shaped structure for the rotor and a △ – shaped layout for the stator. It has outstanding fault isolation capabilities and a 12% increase in voltage output stability on the grid side, making it suitable for scenarios with strict grid access requirements; Distributed projects with limited space can choose the Y-Y symmetric connection scheme, which saves 40% of wiring space and shortens installation cycles by 30%. It requires a redundant circuit breaker protection system.
2. Electrical construction plan for the booster station
Select high reliability electrical equipment based on load capacity and transmission distance, with cable specifications and materials that meet design requirements, reasonable layout to avoid electromagnetic interference, strict wiring according to drawings, and proper grounding, lightning protection, and insulation treatment. Equipped with a real-time monitoring system to dynamically monitor equipment parameters.

2、 Automation and Grid Optimization Solution

1. Optimization of automation control

Following the principles of reliability, economy and progressiveness, building a modular electrical system and configuring remote monitoring and fault diagnosis functions can reduce the frequency of on-site inspection by more than 70%, and the annual downtime of a single fan can be reduced from 45 hours to 12 hours.
2. Grid compliance plan
Ensure that the voltage frequency matches the power grid, control the power factor above 0.9, configure anti islanding and overload short-circuit protection devices, and control the total harmonic distortion rate within 5% through filtering devices to meet the technical specifications for grid connection.

3、 Operation and Security Protection Plan

Coastal stations are equipped with anti salt spray electrical control cabinets. In dusty areas, the cooling channels of the cabinets are cleaned monthly, and electrical fasteners are tightened quarterly. Backup circuit breakers are tested regularly, and control system firmware patches are updated in a timely manner to avoid accidents such as accidental disconnection from the grid.
Build multiple lightning protection, overvoltage, and short-circuit protection systems, combined with real-time impedance monitoring systems, to increase the frequency of electromagnetic compatibility testing to 1.5 times that of conventional units, ensuring stable operation of the system under extreme working conditions.