Các bản vẽ kỹ thuật để chế tạo là sản phẩm cuối cùng của khâu thiết kế. Chúng phải thỏa mãn hai mục đích: bao gồm đầy đủ tất cả các thông tin cần thiết để chế tạo và cũng còn là một tiêu chí kiểm soát kỹ thuật đối với các mức độ sửa chữa. Trước cuối thế kỷ 20, rất nhiều bản vẽ kỹ thuật được thực hiện bằng tay với sự trợ giúp của bảng vẽ cơ khí. Sự ra đời của máy tính với giao diện người dùng đồ họa đã có thể giúp thực hiện. | Distance Protections in the Power System Lines with Connected Wind Farms 139 3. Technical requirements for the dispersed power sources connected to the distribution network Basic requirements for dispersed power sources are stipulated by a number of directives and instructions provided by the power system network operator. They contain a wide spectrum of technical conditions which must be met when such objects are connected to the distribution network. From the point of view of the power system automation these requirements are mainly concerned with the possibilities of the power level and voltage regulation. Additionally the behaviour of a wind farm during faults in the network and the functioning of power protection automation have to be determined. Wind farms connected to the HV distribution network should be equipped with the remote control regulation and monitoring systems which enable following operation modes operation without limitations depending on the weather conditions operation with an assumed a priori power factor and limited power generation intervention operation during emergences and faults in the power system type of intervention is defined by the operator of the distribution network voltage regulator at the connection point participation in the frequency regulation this type of work is suitable for wind farms of the generating power greater than 50 MW . During faults in HV network when significant changes dips of voltage occur wind farm cannot loose the capability for reactive power regulation and should actively work towards sustaining the voltage level in the network. It also should maintain continuous operation in the case of faults in the distribution network which cause voltage dips at the wind farm connection point of the times over the borderline shown in Fig. 6. Fig. 6. Borderline of voltage level conditioning continuous wind farm operation during faults in the distribution network 4. Dispersed power generation sources in fault conditions
