Abstract: Provided is a handcart circuit breaker and a contact device thereof including a contact arm and a moving contact. Inner walls of a cylindrical contact finger base in axial direction respectively have a contact finger groove with a spring contact finger for plugging the contact arm and a fixed contact; a rear of the contact finger base sleeves with a front of the contact arm having a positioning groove larger than a fitting end of the support pin, the contact finger base has support pins extending into the contact finger base; a diameter of a circle corresponding to the fitting end of each support pin is larger than a diameter of a circle corresponding to a bottom of each positioning groove; the contact finger base connects with the contact arm and an elastic support structure is arranged between the contact arm and the inner wall of the contact finger base.

Abstract: The present disclosure relates to a method for preventing a maloperation of differential protection of an optical fiber caused by saturation of a single Current Transformer (CT) of 3/2 connection. By applying a combination of the differential judgment and the sub-CT current judgment, reliable identification of internal and external faults is ensured, and the problem of misjudging of the internal fault as the external fault can be prevented as well.

Abstract: The present disclosure relates to a method for quickly identifying disconnection of a Current Transformer (CT) in protection of a 3/2 connection mode based bus. The present disclosure can quickly and accurately identify the disconnection of the CT, thereby avoiding the problem of a maloperation in protection of a bus caused by the disconnection of the CT.

Abstract: A distributed test method applicable to a system-level test of intelligent high voltage equipment. The method includes: firstly, carrying out unified modeling on test equipment behaviors according to test requirements, and generating a general test case for ensuring accuracy and coordination of test behaviors and test time sequences under various work conditions; then, extracting, according to a feature element of role defining, sequence states of same roles from the general test case, and recombining the sequence states according to an execution sequence so as to form test sub-cases of the roles; finally, executing, by each piece of test equipment, corresponding test sub-cases to achieve cooperative linkage by means of information interaction, so as to accomplish entire process simulation of the test conditions.

Abstract: The invention relates to a method of differential protection in the power distribution networks based on phase difference principles. The method comprises the following steps: collecting the current and voltage signals of each loading switch; calculating phase difference between the corresponding currents at two adjacent loading switches, wherein at least one of the two adjacent loading switches accords with ?I? max>n·?IT+?Idz; tripping the two adjacent loading switches if the phase difference corresponding to the two adjacent loading switches being greater than a threshold then a section between the two adjacent loading switches being determined as a fault section. The method only needs to calculate the phase difference between the corresponding currents at the two adjacent loading switches, and achieves the fault determination according to the phase difference being greater than the threshold.

Abstract: Sampling implementation method and device based on conventional sampling GOOSE trip mode. CPU of master NPI plug-in, after receiving a second pulse, transmits sampling pulse generation time and a transmission enable bit to FPGA of the master NPI plug-in at a fixed interval; after detecting the transmission enable bit, the FPGA of the master NPI plug-in judges whether time of its internal timer is greater than/equal to the sampling pulse generation time, if yes, generates a sampling pulse to FPGA of collection plug-in; after receiving sampling pulse, the collection plug-in carries out A/D sampling, and transmits sampled data to the master NPI plug-in; when detecting that all A/D samplings are completed, the master NPI plug-in transmits data packets to protection CPU plug-in. The device includes an MMI plug-in, a protection CPU plug-in, a master NPI plug-in and a collection plug-in. Protection maloperation is thereby reduced.

Abstract: The present invention relates to a method of preventing misoperation about a relay protection device in a smart substation. Reversely operating CPU operation results of two operation records about the relay protection device, in order to form corresponding disassembler codes. According to disassembler codes, calculating similarity of the CPU operation results of the two operation records about the relay protection device by a structured method. Judging whether the similarity is greater than a set threshold or not. If the similarity is greater than the set threshold, the CPU operation results of the two operation records about the relay protection device to be the same, otherwise, the CPU operation results of the two operation records about the relay protection device are judged to be different. The present invention avoids the misoperations of the relay protection device on operation.

Abstract: The present invention relates to a differential protection method for bridge circuit in current converter control system, including the steps of: 1). obtaining sample values of the three-phase current for the current converter control system at AC side thereof, and calculating the absolute value of each sampling value respectively; 2). calculating a value of current at the AC side of the current converter control system; and 3). determining whether to perform a relay protection for the current converter control system according to the value current at the AC side of the current converter control system. The method of the present invention provided, is fast, convenient, and with a small amount of calculation. The current converter control system determines whether to perform a relay protection in a short time. Also it reduces the possibility that the equipment burned because of cannot break the circuit in time.

Abstract: The present invention provides an integrated battery dispatching system with centralized charging and centralized allocation, which comprises an initial parameter setting module (101), a dispatching selection module (102), a delivery parameter setting module (103), a full battery number acquiring module (104), a logistics fleet delivery strategy submodule (105) and a centralized charging station charging strategy submodule (106). The present invention integrally dispatches centralized battery charging, battery dispatching and logistics vehicle allocation, and arranges the battery to be charged with cheap electric energy according to the battery replacement demand of a delivery station in combination with the capacity constraint for a centralized charging station and the power tariff of a power grid.