Results

AN2288

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6

Results

This section shows the results obtained for the reference design. These results were

obtained at a test house using recognized MTE test equipment. There are three types of

tests performed:

1.

Load tests: Voltage and frequency of AC Source is constant, but the load current

varies. These tests are performed for resistive load (unity power factor), 0.5Lag and

0.8Lead.

2.

Voltage tests: Frequency of AC source and load current (basic current) is constant, but

the voltage is changed from minimum (140V) to maximum (280V). This test is

performed at UPF, 0.5Lag, 0.8Lag and at 0.8Lead.

3.

Frequency tests: Voltage and load current (basic current) is constant, but the

frequency of AC Source is changed from 48Hz to 52Hz. This test is performed at UPF,

0.5Lag, 0.8Lag and at 0.8Lead.

6.1

Load tests

The voltage is 234.5V and the frequency of AC source is 50Hz. Below is the table for the

accuracy Vs. load current.

The % error is within the +-1% error for the range 0.05 Ib < I < 5.5Ib, as required for a class1

meter. Here Imax is 5.5In. The startup current is ~11mA, which is ~0.02% of Imax.

Table 1.

Load current Vs% error

Load current Vs% Error

Load Current [A]

UPF (%Error)

0.5 LAG (%Error)

0.8 LEAD (%Error)

53 (5.3Ib)

-0.71

-0.58

-0.68

50 (5Ib)

-0.34

0.08

-0.55

14 (1.4Ib)

-0.22

0.06

-0.54

13 (1.3Ib)

-0.14

0.09

-0.42

4 (0.4Ib)

-0.11

0.11

-0.41

3 (0.3Ib)

-0.04

0.23

-0.28

1 (0.1Ib)

-0.24

0.54

-0.35

0.8 (0.08Ib)

-0.09

0.62

-0.19

0.5 (0.05Ib)

-0.11

-0.74

0.4

0.2 (0.02Ib)

0.19

-0.39

0.79