Modeling Electromechanical Overcurrent Relays Using Singular Value Decomposition
Table 2
The curve-fitting errors of 17 actual operating times for each TDS of the IAC51 relay in milliseconds.
TDS
1
4
7
10
M
Top
SVD
Err
Top
SVD
Err
Top
SVD
Err
Top
SVD
Err
1.5
1115.0
1112.6
2.34
4738.9
4738.9
0.02
9067.1
9067.1
0.01
14322.0
14322.0
0.16
2
753.7
756.8
3.11
3009.2
3011.1
1.87
5700.4
5702.3
1.89
8960.3
8964.3
3.99
3
530.5
529.2
1.31
2009.6
2008.3
1.30
3772.1
3770.0
2.05
5900.0
5896.7
3.25
4
442.2
443.4
1.15
1616.0
1616.3
0.32
3013.9
3014.0
0.10
4698.1
4697.7
0.49
6
362.4
361.8
0.61
1266.8
1266.2
0.59
2342.1
2340.9
1.22
3632.3
3631.1
1.21
8
323.3
322.4
0.82
1094.7
1094.4
0.34
2010.9
2010.4
0.48
3107.9
3106.7
1.18
10
298.2
298.6
0.47
985.7
986.2
0.48
1801.4
1802.0
0.66
2776.2
2778.1
1.92
13
275.0
275.2
0.22
881.8
881.9
0.12
1601.5
1601.3
0.29
2457.8
2455.8
2.04
16
259.3
259.3
0.04
812.5
812.8
0.34
1468.8
1469.2
0.42
2249.4
2250.6
1.25
19
247.4
247.6
0.20
763.2
763.1
0.04
1373.9
1373.6
0.28
2099.8
2099.0
0.84
22
239.5
238.9
0.66
726.4
726.2
0.18
1302.1
1302.0
0.12
1985.9
1984.6
1.29
26
230.6
230.1
0.49
686.3
686.7
0.46
1224.8
1226.1
1.36
1864.8
1865.8
1.06
30
223.7
223.4
0.21
655.8
655.8
0.08
1166.7
1166.5
0.18
1772.3
1773.0
0.66
34
217.4
218.1
0.66
630.5
630.8
0.29
1118.8
1119.1
0.24
1695.6
1696.3
0.67
39
211.6
212.4
0.88
604.8
604.7
0.11
1070.0
1069.4
0.66
1619.2
1619.0
0.15
44
207.1
207.5
0.41
583.8
583.9
0.08
1029.2
1029.4
0.20
1554.7
1553.9
0.88
49
202.9
203.0
0.09
566.3
566.1
0.26
994.7
994.3
0.38
1500.4
1499.8
0.64
TDS: time dial setting; M: multiples of tap value current; top: actual operating time in milliseconds; SVD: fitted value by singular value decomposition; Err: absolute value of difference between top and SVD value; AV: average of absolute values of errors in milliseconds.
