公开(公告)号：US20210373065A1

公开(公告)日：2021-12-02

申请号：US17290284

申请日：2019-08-22

Applicant: HITACHI, LTD.

Inventor： Kazuhisa TAKAMI ,  Shoji YOSHIDA ,  Mitsuyasu KIDO ,  Tatsuya MARUYAMA

IPC: G01R31/12 ,  G01R31/14 ,  G01R31/52

Abstract: A partial discharge detection apparatus includes low-speed and high-speed AD converters. The low-speed AD converter converts an analog signal of an AC waveform flowing through a power cable into a digital signal. The high-speed AD converter converts an analog signal of a partial discharge current into a digital signal. The analog signal is in a plurality of Nyquist frequency domains defined for each of two different types of sampling frequencies. The partial discharge is detected by a partial-discharge-detection digital signal processing unit based on the maximum value or the sum of a current value obtained from the digital signal of the partial discharge current obtained by the conversion of the high-speed AD converter, for each phase of the AC waveform, which is obtained from the digital signal of the AC waveform flowing in the power cable. The digital signal is obtained by the conversion of the low-speed AD converter.

公开(公告)号：US20220128614A1

公开(公告)日：2022-04-28

申请号：US17600151

申请日：2020-04-23

Applicant: HITACHI, LTD.

Inventor： Hiromichi YAMADA ,  Tatsuya MARUYAMA ,  Mitsuyasu KIDO

IPC: G01R31/12

Abstract: A distribution pattern of a combination of a charge quantity and an occurrence phase angle of each of the partial discharges occurring in one or a plurality of cycle periods of an applied voltage of the power transmission cable is generated, differential data including a difference between the numbers of occurrences of the partial discharge for each combination of the charge quantity and the occurrence phase angle in two or more latest distribution patterns is generated, and the degree of progress of the partial discharge is determined based on data of the latest distribution patterns and the differential data.

公开(公告)号：US20140098706A1

公开(公告)日：2014-04-10

申请号：US14044895

申请日：2013-10-03

Applicant: Hitachi, Ltd.

Inventor： Tatsuya MARUYAMA ,  Tsutomu YAMADA ,  Mitsuyasu KIDO ,  Shoji YOSHIDA

IPC: H04J3/06

CPC classification number: H04J3/0638 ,  H04J3/0667 ,  H04L47/30

Abstract: Communication control equipment is connected to a plurality of communication control equipment via a network and is configured to be time-synchronized with the plurality of communication control equipment by using a time synchronization procedure using a communication including at least request packets and acknowledgement packets. The communication control equipment includes a receiving-interval measurement section configured to measure a receiving interval of request packets from the plurality of communication control equipment; and a queuing-occurrence determination section configured to detect conflict of the request packets from any of the plurality of communication control equipment on a basis of the receiving interval of the request packets measured by the receiving-interval measurement section. The communication control equipment is configured to determine whether to transmit an acknowledgement packet to the communication control equipment that has transmitted the request packets based on a detection result of the queuing-occurrence determination section.

Abstract translation: 通信控制设备经由网络连接到多个通信控制设备，并且被配置为通过使用至少包括请求分组和确认分组的通信的时间同步过程与多个通信控制设备进行时间同步。 通信控制设备包括接收间隔测量部分，被配置为测量来自多个通信控制设备的请求分组的接收间隔; 以及排队发生判定部，其基于由所述接收间隔测量部测量出的所述请求分组的接收间隔来检测来自所述多个通信控制设备中的任一个的所述请求分组的冲突。 通信控制设备被配置为基于排队发生确定部分的检测结果来确定是否向已发送请求分组的通信控制设备发送确认分组。

公开(公告)号：US20240183894A1

公开(公告)日：2024-06-06

申请号：US18284934

申请日：2022-06-07

Applicant: HITACHI, LTD.

Inventor： Hiromichi YAMADA ,  Shinsuke ONOE ,  Mitsuyasu KIDO

IPC: G01R31/14 ,  G01R31/28 ,  G01R31/58

CPC classification number: G01R31/14 ,  G01R31/2846 ,  G01R31/58

Abstract: A partial discharge determination method executed in a partial discharge determination apparatus that determines whether or not partial discharge has occurred in a power transmission facility includes: acquiring measurement data representing a charge amount and a phase of each partial discharge occurring in the power transmission facility; removing or reducing noise included in the measurement data based on statistical information; generating φ-q-n data representing a charge amount, a phase, and the number of pulses of each of the partial discharge and the noise included in the measurement data from the measurement data from which the noise has been removed or reduced; and determining whether or not at least the partial discharge has occurred by using a learning model generated by performing machine learning using the φ-q-n data of the partial discharge and the noise based on the φ-q-n data generated by a φ-q-n data generation unit.

公开(公告)号：US20160277288A1

公开(公告)日：2016-09-22

申请号：US15033670

申请日：2014-09-05

Applicant: HITACHI, LTD.

Inventor： Tatsuya MARUYAMA ,  Tsutomu YAMADA ,  Chikashi KOMATSU ,  Mitsuyasu KIDO ,  Shouji YOSHIDA

IPC: H04L12/721 ,  H04L12/42

CPC classification number: H04L45/34 ,  H04L12/422 ,  H04L12/437 ,  H04L45/28 ,  H04L47/31

Abstract: An object of the present invention is to provide a network system or the like in which the construction cost of a network for a plurality of control systems is suppressed which is excellent in resistance to a network failure. In order to solve the problems, according to the present invention, there is provided a network system including a plurality of communication devices that are disposed in a plurality of bases, and are grouped into predetermined control systems for each of the devices which transmit and receive packets to and from each other so as to monitor or control target equipment, and a plurality of relay devices each of which includes a plurality of communication ports and transmits a packet transmitted by the communication device to another communication device, in which a plurality of communication devices disposed in each base are connected in parallel between the two relay devices, the relay devices disposed in different bases are connected to each other in a ring shape via a network, and a plurality of communication devices disposed in at least one base include communication devices belonging to different control systems.

Abstract translation: 本发明的目的是提供一种网络系统等，其中抑制了多个控制系统的网络的建设成本，其对网络故障的抵抗性优异。 为了解决这些问题，根据本发明，提供了一种网络系统，包括设置在多个基站中的多个通信设备，并且被分组为用于发送和接收的每个设备的预定控制系统 分组到彼此并且用于监视或控制目标设备，以及多个中继设备，每个中继设备包括多个通信端口，并将由通信设备发送的分组发送到另一个通信设备，其中多个通信 设置在每个基座中的装置并联连接在两个中继装置之间，设置在不同基座中的中继装置经由网络以环形方式彼此连接，并且设置在至少一个基座中的多个通信装置包括通信装置 属于不同的控制系统。

公开(公告)号：US20220131681A1

公开(公告)日：2022-04-28

申请号：US17600154

申请日：2020-02-13

Applicant: Hitachi, Ltd.

Inventor： Tatsuya MARUYAMA ,  Mitsuyasu KIDO ,  Shoji YOSHIDA ,  Kazuhisa TAKAMI ,  Takamichi ENDO

IPC: H04L7/00 ,  H04L7/04

Abstract: In the related art, since there is a difference in communication delay time in a round-trip communication path due to packet clogging in a network configuration using a network relay device, there is a problem that time cannot be synchronized. In order to solve the above problem, in the present invention, a time synchronization unit 131 is controlled by the time synchronization control unit 130 to perform time synchronization once, delays of an egress path and an ingress path of the time packet on the basis of the synchronization time are calculated, and time synchronization processing is executed using a time of the time packet in a case where the calculated values are equal to each other.

公开(公告)号：US20210231747A1

公开(公告)日：2021-07-29

申请号：US17098771

申请日：2020-11-16

Applicant: Hitachi, Ltd.

Inventor： Hiromichi YAMADA ,  Mitsuyasu KIDO

IPC: G01R31/52 ,  G01R31/58 ,  G06N3/08

Abstract: An object of the present invention is to propose a partial discharge determination device and method that can highly reliably determine the degree of progress of partial discharge occurring in an underground power transmission cable without preparing plural standard patterns. A distribution pattern of a set of the charge amount and the occurrence phase angle of each partial discharge occurring in a period of one or more cycles of an applied voltage of a power transmission cable is sequentially generated, a first classification process in which the pattern is classified into any one of classes on the basis of a standard distribution pattern for each class and a second classification process in which the distribution pattern are executed, a classification result by the first classification process is evaluated on the basis of a classification result by the second classification process, and the degree of progress is determined.

公开(公告)号：US20160360497A1

公开(公告)日：2016-12-08

申请号：US15172315

申请日：2016-06-03

Applicant: Hitachi, Ltd.

Inventor： Tatsuya MARUYAMA ,  Tsutomu YAMADA ,  Mitsuyasu KIDO ,  Shouji YOSHIDA ,  Kazuhisa TAKAMI

IPC: H04W56/00 ,  H04W72/12

CPC classification number: H04W56/001 ,  H04L47/36 ,  H04L47/628 ,  H04L49/3072 ,  H04L51/04 ,  H04L65/608 ,  H04N21/45457 ,  H04N21/6437

Abstract: There is provided a communication control device including: a real-time communication status extraction unit that acquires a communication timing of real-time data; a dynamic fragment size determination unit that acquires a fragment size of sending data which can be sent until the communication timing acquired by the real-time communication status extraction unit; a fragment processing unit that fragments non-real-time data to have at least a fragment size which is equal to or less than the fragment size acquired by the dynamic fragment size determination unit; and a communication unit that sends the non-real-time data, which is fragmented by the fragment processing unit, before the communication timing of the real-time data.

Abstract translation: 提供了一种通信控制装置，包括：实时通信状态提取单元，其获取实时数据的通信定时; 动态片段大小确定单元，其获取可以发送的发送数据的片段大小，直到由所述实时通信状态提取单元获取的通信定时; 片段处理单元，其将非实时数据分段成至少具有等于或小于由所述动态片段大小确定单元获取的片段大小的片段大小; 以及通信单元，其在实时数据的通信定时之前发送由片段处理单元分段的非实时数据。