Resistance to nanosecond pulse interference. Electromagnetic compatibility of technical means. Requirements and test methods.
The nature of the appearance of nanosecond pulse interference
Starters, automata, relays, when the contacts of an electrical circuit are opened, form a discharge, a spark similar to a static discharge, this discharge is induced by an electromagnetic field on nearby wires, from these nearby wires in which there are nanosecond interference, in one harness there are other circuits that receive interference by transformer communication, Nanoseconds are a frequency spectrum from 2 up to 200 MHz with a power of up to 450kW per pulse.
The degree of rigidity of the test nanosecond pulse interference
1st.w. - ± 0.5 kV 5kHz and ± 0.5 kV 100kHz
2st.w. - ±1.0kV 5kHz and ±1.0kV 100kHz (local lines)
3st.w. - ±2.0kV 5kHz and ±2.0kV 100kHz (field connection lines)
4st.w. - ± 4.0kV 5kHz and ± 4.0kV 100kHz (communication lines with BB equipment, DC and AC power port)
Types of tests nanosecond pulse interference
Through capacitive tongs - all ports except the power port
Through the connection scheme of the interchange - to the port of the DC and AC power supply
Test method nanosecond pulse interference
The wires of the test lines are placed in 1 m capacitive tongs, interference is applied to the lines relative to the "ground".
Packets of pulses are fed with a perud of 0.33 seconds, within 1 minute a test of each polarity, each frequency, a total of 4 tests.
Each degree of rigidity must be confirmed by steps from the lowest to the highest. If it is tested on 4 st.zh. then the total number of tests is 4 * 4 = 16 The test time of one degree of rigidity takes about 5 minutes without taking into account preparation. Each port is tested separately, it is allowed to test a common galvanic group of ports together, joint testing of several galvanically isolated ports is allowed only for research purposes.
Nanosecond pulse interference test scheme
A picture of the test stand or see here
Parameters of test signals nanosecond pulse interference
The resistance of the source \ generator is 50 ohms
Read more about the test schemes here
Voltage from 0.5kV to 4kV
The shape of the pulse signal is triangular, the front is 5ns, the decline is 50 ns.
In 5kHz packs of 1500 pulses, in 100kHz packs of 75 pulses (5/50 ns) the length of the pack is 15 ms
Pulse power from 15kW to 450kW
Energy 25 J
The resistance of the source \ generator is 50 ohms
Read more about the test schemes here
