BI-DIRECTIONAL POWER FLOW AC-DC CONTROLLER

摘要

Invention corresponds to electrical engineering branch, more specifically to the electrical transport branch. The target of the invention is to provide stabile bi-directional power flow in AC-DC power controller system keeping constant parameters of the unidirectional power flow transformer of substations existing in exploitation. The target in the invention is reached in such a way that in bi-directional power flow AC-DC controller with three-phase three-winding main grid's transformer, two secondary three-phase windings of which are connected in the star connection scheme. Each but both connection's are mutually opposite phased, neutral point of each star scheme are connected through a separation reactor, a center tap of which is used as negative voltage pole of controller's output voltage. Sixth free outputs of the windings each are connected to anode contacts of thyristors, cathode contacts of which are integrated providing a positive output pole of the controller and between this pole and negative one capacitor is installed. To the primary network a supplementary transformer is connected with smaller rated power also having two three-phase secondary winding groups, each phase winding of which is connected coordinated in series with respecting phase windings of the main transformer but mutual connection points are connected to anodes of right direction thyristors and through thyristors of the reverse direction windings of the supplementary transformer are connected to parallel the thyristors of the right direction. The anodes of the reverse direction thyristors are connected to the cathodes of the thyristors of right direction. The operation permitting input of control device of the reverse direction thyristors is connected to an output of sensor of current installed in circuit of the positive voltage pole of controller. Signal of permission corresponds to the negative reverse direction of the controller's DC current but through inverter of signal output of the sensor it is connected to control device of thyristors of the right direction.