IEC 61000-4-17:2002 pdf download

IEC 61000-4-17:2002 pdf download.Electr omagnetic compatibility (EMC)-Part 4-17: Testing and measurement techniques – Ripple on d.c. input power port immunity test.
The test levels are a peak-to-peak voltage expressed as a percentage of the nominal d.c. voltage Ud.c.
The amplitude of the ripple voltage is represented in figure 1 by the difference Umax— Umin.
The frequency of the ripple is the power frequency or its multiple 2, 3 or 6, as specified by a product committee or according to the EUT manufacturer’s specifications or according to the characteristics of the rectifier system (see also clause A.2).
The waveform of the ripple voltage, at the output of the test generator, has a sinusoid-linear character.
A sinusoidal-linear characteristic can be described as a part of a sine wave and a line, tangent to the decreasing side of the rectified wave, that intersects the rising edge of the following half- wave; the voltage difference between the peak value of the sine wave and the point of intersection to the following half-wave is the ripple voltage (see figure 1). The decreasing voltage can be assumed as a linear function in the presence of constant current loads. The voltage deviation, in the case of a constant resistor or constant power load, is very small and can be considered acceptable for the purpose of the test.
Deviations from the defined waveform, due to the impedance of the EUT, are allowed during the test. However, care should be taken in order to assess that the deviation from the original waveform is not caused by limitation of the generator. Furthermore, the peak-to-peak value and the frequency of ripple shall be maintained by adjustment in order to maintain the severity of the test.
The graphical representation of the waveform obtained from a single-phase bridge and a three- phase bridge rectifier is shown in figure 1; the difference Umax — Umin is the percentage of the nominal d.c. voltage and corresponds to the selected test level.
NOTE Information on the phenomenon and on the selection of the test level is given in annex A, clauses A.1 and A.2.
6.1 Characteristics and performance of the generator
The test generator shall be able to operate in continuous mode with the following main specifications:
— output voltage range: up to 360 V;
— output voltage change with load: less than 5 %;
(0 to rated current)
— output voltage waveform: alternating component at power frequency or its
multiple, with a sinusoid-linear character,
superimposed on the d.c. voltage
— output voltage tolerance: ±10 %
— output current (steady state): up to 25 A;
— peak output current capability: +2,5/—0,5 times the steady-state current;
(maximum allowable duration 5 ms)
— ripple frequency tolerance: ±1 %.
NOTE The 360 V output voltage value covers the test condition of a 300 V d.c. supply voltage plus a 15 % ripple corresponding to test level 4.
The use of a generator with higher or lower voltage/current capability is allowed provided that the other specifications (waveform, change with load, peak output current/steady-state current ratio, etc.) are preserved. The test generator output power/current capability shall be at least 20 % greater than the EUT power/current ratings.
The generator must be able to produce positive and negative peak current with positive voltage output.
Examples of generators can be found in clause A.3.
Figure A.1 shows a schematic diagram of a generator based on a rectifier system; figure A.2 shows a schematic diagram of a generator based on a programmable power supply with controller.
6.2 Verification of the characteristics of the generator
In order to compare the test results the following characteristics of the generator shall be verified:
— the sinusoid-linear character of the ripple signal shall be maintained at maximum output voltage, with the output connected to a resistive load of 60 2;
— the sinusoid-linear character of the ripple signal shall be maintained at maximum current (25 A), with the output connected to a resistive load (e.g. 2,4 2 at output voltage of 60 V);
— the ripple frequency;
— the peak output current shall meet the requirements of 6.1, when switching the generator output from 0 V to 60 V and driving an uncharged capacitor whose value is at least 1 700 iF (as in IEC 61000-4-11).
The verification of a generator with voltage/current capability less than specified in 6.1 shall be made with load conditions reflecting the rated voltage and current.
The measurement uncertainty of the instrumentation (e.g. low-frequency oscilloscope, d.c. voltmeter and a.c. peak-to-peak voltmeter) shall be less than or equal to 2 %.