Chinese Academy of Sciences

Nr Electric Co., Ltd

Nr Engineering Co., Ltd

Huimin Wang

Jun Chen

Kai Wang

Quanrong Shen

Huazhong Li

Wei Yan

Wenjie Ren

Ying Teng

A nanobioremediation method is for soil in a high-concentration polycyclic aromatic hydrocarbon (PAH)-contaminated site. The method includes adding a carbon nanomaterial and a base fertilizer to soil in a high-concentration PAH-contaminated site, evenly broadcast sowing alfalfa seeds to the contaminated soil, and keeping the soil moisture content at 60% of the field moisture capacity, and when the alfalfa grows to the flowering or maturity stage, harvesting and removing the plants from the contaminated soil.

Nanobioremediation method for soil in high-concentration polycyclic aromatic hydrocarbon (PAH)-contaminated site

A frequency-conversion differential protection method for an output transformer of a static frequency convertor system. The method comprises: a protection device measuring a three-phase current at each side of an output transformer of an SFC system; according to the connection manner of the output transformer, using a triangle side as a reference to conduct phase correction on a star side; at the same time, taking into account different secondary rated currents at each side of the transformer to adjust a balance coefficient of each side, so as to form sampling values of a correcting current and a differential current at each side, and using a startup and shut-down protection algorithm free from frequency influence in generator protection to calculate amplitude values of the correcting current, the differential current and a restraint current; and according to the magnitudes of the differential current and the restraint current, using the ratio restraint differential characteristic to achieve the frequency-conversion ratio differential protection of the output transformer. The present protection method is suitable for large-scale frequency change. Compared with the current quick-breaking protection, the sensitivity of internal failure detection in the output transformer is greatly improved.

Frequency-conversion differential protection method for output transformer of static frequency converter system

Growing community of inventors

Jiangsu, China

Huimin Wang