ST STEVAL-SCR002V1, Руководство пользователя

Страница: 10 / 28

4.2 Conducted EMI noise
The EN55014 standard defines the maximum levels of the conducted noise due to AC mains current switching.
The
STEVAL-SCR002V1 evaluation board complies with the standard, as shown in the figure below.
No impact of the low-side SCR bypass topology compared to the original topology has been measured. The
results are identical.
Figure 13. EN55014 standard validation (average measurement) - V
AC
= 230 V/50 Hz, P = 1000 W
4.3 EMC immunity
We evaluated the immunity of the STEVAL-SCR002V1 subject to fast transient/bursts on the supply, according to
the test method described in the IEC 61000-4-4 standard.
Figure 14. Test schematic and waveform specification for IEC61000-4-4
We tested two couplings: one between line and ground, and one between neutral and ground. For each coupling,
we applied bursts to positive and negative polarities.
We achieved the same IEC61000-4-4 withstanding level with the original configuration using a relay and an NTC.
The low side bypass SCR solution has no impact on the burst immunity system performance.
Table 1. IEC61000-4-4 test results for the STEVAL-SCR002V1
Coupling Minimum level
Original
configuration
level
A class
(1)
B class
(2)
A class
(1)
B class
(2)
A class
(1)
B class
(2)
L N L N
+ - + - + - + -
2.5 kV 3.8 kV 6 kV 2.5 kV >4 kV >4 kV >4 kV >4 kV 2.5 kV >4 kV 2.5 kV >4 kV
1. Normal operation within the limits specified by the manufacturer.
2. Temporary loss of function, degradation, or performance, which ceases when disturbance finishes. After this temporary loss,
the equipment under test recovers its normal performance without any operator’s intervention.
UM2948
Conducted EMI noise
UM2948 - Rev 1
page 10/28