发明名称 |
DIGITAL FILTER PROCESSING UNIT, DIGITAL PROTECTION RELAY DEVICE AND DIGITAL DIFFERENTIAL RELAY DEVICE |
摘要 |
PURPOSE:To attain fast discrimination of relay operation with high accuracy by obtaining an input data required for the calculation of a protection relay at a frequency (density) being N times the sampling frequency and constituting a protection relay device through the use of the processing unit of such data. CONSTITUTION:An input data representing the state variable such as an inputted voltage or current is subjected to A/D conversion (4) for each sampling period Ts. Then filter processing by digital filter calculation is applied. The filter processing is repeated based on the preset filter coefficient for a period TF being 1/N of the sampling period Ts and it is possible to offer the input data required for the calculation of the protection relay at a frequency higher than the sampling frequency thereby attaining high speed operation discrimination and highly accurate operation of the protection relay. Furthermore, the frequency characteristic in the filter calculation operation is a characteristic passing the fundamental wave frequency component of the input data while eliminating a high frequency, and even if filter processing is applied to a simulated input data in place of a true input data, the fundamental wave data equal to the processing of sampling substantially at a short pitch of the frequency being a multiple of N is obtained. |
申请公布号 |
JPH01284009(A) |
申请公布日期 |
1989.11.15 |
申请号 |
JP19880112748 |
申请日期 |
1988.05.10 |
申请人 |
HITACHI LTD |
发明人 |
KIDO MITSUYASU;CHIBA TOMIO;KAWAKAMI JUNZO |
分类号 |
H02H3/02;H02H3/28;H03H17/00;H03H17/02 |
主分类号 |
H02H3/02 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|