公开(公告)号：EP1159778A1

公开(公告)日：2001-12-05

申请号：EP00904857.0

申请日：2000-02-15

申请人： Nesa A/S ,  Boyd, Hugh Allison

发明人： BOYD, Hugh, Allison

IPC分类号： H02H9/04 ,  H02J3/12

CPC分类号： H02J3/1821 ,  Y02E40/30

摘要： The invention consists of a method to greatly enhance the Mvar absorption of a high voltage shunt reactor in response to excess Mvar suddenly appearing on a high voltage transmission system. A high voltage capacitor is connected in series with a shunt reactor in order to increase the reactor voltage, and thereby the Mvar absorption, as a function primarily of the capacitor value in combination with the dynamic impedance of the reactor in the saturated region of the reactor V/I characteristic. The new with the invention is that the Mvar absorption of the reactor is no longer dependent on the system voltage alone. The invention also includes a reactive device consisting of a multi phase shunt reactor with a capacitor connected in series with each phase.

公开(公告)号：EP1820034A2

公开(公告)日：2007-08-22

申请号：EP05803993.4

申请日：2005-11-18

申请人： Nesa A/S

发明人： BJØRN, Lars, Nørgaard

IPC分类号： G01R31/02 ,  H02H3/52 ,  H02J13/00

CPC分类号： H04W4/14 ,  G01R1/00 ,  G01R15/246 ,  G01R19/2513 ,  G01R31/025 ,  G01R33/0322 ,  H04L67/12

摘要： The present invention relates to a monitoring system for detecting earth faults in an electrical power supply grid. The system may comprise a plurality of monitoring devices mounted in a number of monitoring locations, each of the monitoring devices may include a detector for detecting level of harmonics in the electrical power. The level of harmonics is preferably detected in a specific frequency range. The monitoring devices may further include a memory device for storing a harmonics reference value and may still further include a processor for comparing the level of harmonics with the reference level. The monitoring device may even still further include a communication device for transmitting an alarm provided the level of harmonics is above the reference level for a specific period of time.

公开(公告)号：EP1625408A2

公开(公告)日：2006-02-15

申请号：EP04732275.5

申请日：2004-05-12

申请人： Kasmatic Innovation A/S ,  Nesa A/S

发明人： BJORN, Lars, Norgaard

IPC分类号： G01R15/24 ,  G01R35/00

CPC分类号： G01R15/247 ,  G01R15/246 ,  G01R35/005

摘要： An electric current measurement device, comprises a housing defining a first open end and a second open end. A first sealing means has an aperture and has an overall geometrical configuration corresponding to the overall geometrical configuration of the first open end. The first sealing means further comprises an aperture adapted for receiving a first optical fibre to be fixated by means of a first fixture mean. A first optical lens has a reception part for receiving the first fixture means for mounting the first optical fibre in optical continuation with the first optical lens. A first polarisation filter mounted in the housing in optical continuation with the first optical lens. A glass rod is received in and encapsulated within the housing in optical continuation with the first polarisation filter. The glass rod is constructed from a material having magneto-optical properties. The device further comprises a second polarisation filter mounted in the housing in optical continuation with the glass rod, a second optical lens mounted in the housing, a second fixture means for fixating a second optical fibre, and a second sealing means for sealing the second end of the housing.

公开(公告)号：EP1865756A1

公开(公告)日：2007-12-12

申请号：EP06388040.5

申请日：2006-06-06

申请人： Nesa A/S

发明人： The designation of the inventor has not yet been filed

IPC分类号： H05B37/03

CPC分类号： H05B37/03 ,  H05B37/032 ,  H05B37/034

摘要： The present invention relates to a lighting system. The system comprises a pair of power supply lines, a plurality of light sources connected to said pair of supply lines, a monitoring unit, and an alert receiving unit communicating with said monitoring unit. The pair of power supply lines may constitute a supply line and a return line. The supply line and said return line are connected to said plurality of light sources and through said monitoring unit, the pair of power supply lines providing electrical power to said plurality of light sources. The monitoring unit may comprise a voltage measuring circuit measuring the voltage across said pair of power supply lines. The monitoring unit may further comprise a current measuring circuit measuring the current flowing through said supply line or said return line in response to the electrical power provided to said plurality of light sources. The monitoring unit defines a first time frame and a first point of time during said first time frame, during said first time frame a first steady state situation for said plurality of light sources is achieved. The monitoring unit measures at said first point of time a first voltage level by means of the voltage measuring circuit and the monitoring unit measuring at the first point of time a first current level by means of the current measuring circuit. The monitoring unit determining a first load resistance representing the active load resistance for the plurality of light sources being active during the first time frame based on the first voltage level and the first current level, the monitoring unit defining a second time frame and a second point of time during the second time frame, during the second time frame a second steady state situation for the plurality of light sources is achieved. The second time frame being defined to take place after the first time frame has expired. The monitoring unit measuring at the second point of time a second voltage level by means of the voltage measuring circuit, and a second current level by means of the current measuring circuit, the monitoring unit determining a second load resistance representing the active load resistance for the plurality of light sources being active during the second time frame based on the second voltage level and the second current level. The monitoring unit generates a first alert message provided the difference between the first and second load resistance exceeds a first specific threshold constituting a first alert criterion. The monitoring unit still further comprises a communication unit for sending the first alert message to the alert receiving unit, and the alert receiving unit acting or alerting in response to the reception of the first alert message.

摘要翻译： 本发明涉及一种照明系统。 该系统包括一对电源线，连接到所述一对电源线的多个光源，监视单元和与所述监视单元通信的警报接收单元。 一对电源线可以构成供电线和返回线。 供电线路和所述返回线路连接到所述多个光源并且通过所述监视单元，所述一对电源线路向所述多个光源提供电力。 监测单元可以包括测量所述一对电源线上的电压的电压测量电路。 监视单元还可以包括电流测量电路，其响应于提供给所述多个光源的电力来测量流过所述供应线或所述返回线的电流。 监测单元在所述第一时间帧期间定义第一时间帧和第一时间点，在所述第一时间帧期间，实现所述多个光源的第一稳态状态。 所述监视单元借助于所述电压测量电路在所述第一时间点测量第一电压电平，并且所述监视单元通过所述电流测量电路在第一时间点测量第一电流电平。 所述监视单元基于所述第一电压电平和所述第一电流电平确定代表所述多个光源的有效负载电阻的第一负载电阻在所述第一时间帧期间是有效的，所述监视单元限定第二时间帧和第二点 在第二时间帧期间，实现多个光源的第二稳定状态。 第二个时间段定义为在第一个时间段到期后进行。 监视单元通过电压测量电路在第二时间点测量第二电压电平，并通过电流测量电路测量第二电压电平，监视单元确定表示第二负载电阻的第二负载电阻， 多个光源在第二时间帧期间基于第二电压电平和第二电流电平而被激活。 如果第一和第二负载电阻之间的差超过构成第一警报标准的第一特定阈值，则监视单元产生第一警报消息。 监视单元还包括用于向警报接收单元发送第一警报消息的通信单元，并且警报接收单元响应于接收到第一警报消息而起作用或警报。