Xj Group Corporation, XJ Electrical CO., Xuchang XJ Software Technelogy Co and State Grid Corporation of China | Date: 2016-09-09
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.
Xj Group Corporation, XJ Electrical CO., State Grid Corporation of China and Xuchang XJ Software Technology Co. | Date: 2016-09-22
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.
State Grid Corporation of China, XJ Group Co. and XJ Power Co. | Date: 2013-08-07
A battery replacement apparatus and a battery replacement system are applicable to an electric commercial vehicle. The battery replacement apparatus comprises: a main frame; a positioning mechanism constituted by a vertical positioning mechanism and a horizontal positioning mechanism, the vertical positioning mechanism being arranged within the main frame, and the horizontal positioning mechanism being arranged under the main frame; a rotating mechanism arranged under the vertical positioning mechanism; a a lateral movement mechanism arranged on the rotating mechanism; and a push-pull mechanism arranged on the lateral movement mechanism. The battery replacement system comprises the battery replacement apparatus, and also comprises a power supply unit, a charging unit, and a monitoring and communication unit. The battery replacement apparatus can automatically replace battery packs in electric commercial vehicles, thus the efficiency of battery replacement is increased, and more battery replacements can be completed per unit of time, thereby allowing a charger to perform a fuller charge and to have an improved utilization rate.
State Grid Corporation of China and Xj Group Corporation | Date: 2012-10-14
The present invention relates to a networked differential protection method for a distribution network based on overhauling of terminal equipment. The present invention comprises the steps of detecting in real time an operation state of a terminal equipment, and reconstructing a differential logic when there is a terminal equipment under an overhaul state so as to bring it into a state in which an overhaul mode and an operation mode are in parallel; for the operation mode in the state in which an overhaul mode and an operation mode are in parallel, only calculating data of all nodes in normal operation in an electrical element by a differential protection for the electrical element, while excluding data under the overhaul state in the electrical element from taking part in calculation. With the method of the present invention, the operation switch may be reliably switched off and failures may be isolated when they appear during an experiment of a scheduled test. The experiment of the scheduled test may be completed, and the correctness of the electrical topological configuration and the terminal equipment network configuration of the networked differential protection device may be automatically verified.
Xj Group Corporation, Xuchang Xj Software Technologies Ltd, XJ Electrical CO., Xi'an Jiaotong University and State Grid Corporation of China | Date: 2016-03-21
The invention relates to rapid online diagnosis method of high-power rectifier open-circuit fault, including: 1) collecting actual output direct current value i_(d)(t_(0)) and three phase input electric current instantaneous values i_(a)(t_(0)), i_(b)(t_(0)) and i_(c)(t_(0)) of rectifier at t_(0 )moment, and calculating theoretical output direct current value i_(d) of the rectifier according to i_(a)(t_(0)), i_(b)(t_(0)) and i_(c)(t_(0)); 2) comparing i_(d) (t_(0)) and i_(d)(t_(0)), when i_(d) (t_(0)) is not more than k1i_(d)(t_(0)), comparing absolute value of maximal three phase input electric current instantaneous value and pre-set threshold value A_(1), if the maximal three phase input electric current instantaneous value is not less than A_(1), the rectifier appears open-circuit fault. The inventive method is simple, with no complicated step for performing fault diagnosis, of course, the short fault diagnosis period and tripping protection occupation time is short, but it also can protect the rectifier effectively and prevent equipment damage from longtime working under fault condition.
State Grid Corporation of China and Xj Group Corporation | Date: 2012-10-15
The present invention relates to a busbar differential protection method. For each bay, firstly, zero-crossing point of voltage is determined according to sample values of voltage, then the current values are re-sampled on a current fitting curve by using zero-crossing point of voltage as a synchronous signal according to a given sampling time period to get a sample sequence. The sample sequence is comprised of current values of sampling points and sample serial numbers. The sample serial numbers of sampling points at the same time are same for the sample sequence of respective interval. Finally, computing is done to sample sequences of respective intervals, and differential protection is achieved.
State Grid Corporation of China and Xj Group Corporation | Date: 2012-10-16
The present invention relates to a method for generating a current differential protection supernode based on an electrical topology of a regional distribution network, which belongs to the fields of automation of electrical power systems and relay protection. The present invention generates several supernode differential protection elements, i.e., differential protection objects, and backup differential protection elements by circularly using a depth-first search method according to the inputted branch-node associative data table reflecting the electrical topology of the distribution network. the present invention can accurately located and quickly isolate the faults in the distribution network system, reduce the probability of power cut in the non-fault lines, reduce the coverage of power cut, quickly reconstruct and self-heal the distribution network, and solve the effect of the distributed access system on the distribution network protection.
State Grid Corporation of China and Xj Group Corporation | Date: 2012-10-14
The present invention relates to a centralized and networked protection system and method of regional distribution network, and belongs to the field of electrical system automation and relay protection. The protection system includes at least two centralized protection devices, an intelligent terminal and a communication network module, the centralized protection devices being communication with the intelligent terminal via the communication network module, the intelligent terminal being configured along with switching devices to distribute in each line section, for sampling data, backup protection and executing of tripping and closing commands, the centralized protection devices configured in the monitoring center of the regional distribution network, for generating differential protection elements based on the information sampled by the intelligent terminal and the topologic structure of the regional distribution network; and for determining the region where fault occurs and sending tripping and closing control commands.
State Grid Corporation of China and XJ Group Co. | Date: 2013-09-04
This disclosure discloses a battery charge/swap monitoring system and method based on the internet of things. The system comprises a terminal information collecting device, a battery charge/swap station monitoring device, and a regional monitoring device. The terminal information collecting device carries out identity identification, state information collection and dynamic orientation on a terminal device by using an information sensing mode, transmits the identity identification information to the battery charge/swap station monitoring device through a wired network, and transmits the state information and orientation information to the regional monitoring device through a wireless network. The battery charge/swap station monitoring device receives the identity identification information of the terminal device, monitors an operating state of a battery charge/swap station, carries out metering and billing on a battery charge/swap process, and transmits the state information, the metering and billing information and the identity identification information of the terminal device to the regional monitoring device. The regional monitoring device monitors the terminal devices and the battery charge/swap stations in its jurisdiction area, and takes statistics on the metering and billing information. Thus, effective monitoring and management of a terminal device and a battery charge/swap station can be realized.
Yi Y.-H.,XJ Group Corporation
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2013
This paper analyzes the relationship among the concepts of mean time between failures, failure rate and life, discusses the limitations of life research about present relay protection devices, and collects the statistics of relay protection devices' life and failure rate in different time from an electric grid corporation. According to the characteristics that relay protection devices are repairable, and by amending the data of relay protection devices which are untimely out of service due to the present management system, Marquardt method is utilized to estimate the parameter of two-parameter Weibull distribution function of relay protection devices' life, thereby the cut-off of failure rate and the distribution curve function of failure rate are obtained. The paper analyzes the main influence mechanism and proposes the methods to extend the life, so as to provide the theoretical basis for relay protection devices' life requirement.