Test purposes of electrical fast transient pulse clusters
The switching of inductive loads by mechanical switches in a circuit usually interferes with other electrical and electronic equipment in the same circuit. Such disturbances are characterized by clusters of pulses, high repetition rates of pulses, short rise times of pulse waveforms, and low energy of individual pulses.
In practice, the probability of equipment failure caused by electrical fast transient pulse group is less, but the situation of equipment misoperation is often seen, unless there is a suitable countermeasure, it is difficult to pass. The purpose of conducting electrical fast transient pulse swarm testing is to establish a common basis for evaluating the resistance of electrical and electronic equipment to the impact of electrical fast transient pulse swarm.
The mechanism of the test is the accumulation effect of the common mode current generated by the pulse group on the distributed capacitance energy of the line when it flows through the line. When the energy accumulates to a certain degree, it may cause the line (or even the equipment) to work wrong. Usually, once the circuit under test goes wrong, it will go wrong continuously. Even if the pulse voltage is slightly reduced, the error situation will continue to be explained.
Equipment for rapid pulse group test
Figure 1 shows the basic circuit of electrical fast transient generator.
Figure 2 shows the waveform of the pulse group.
U: high voltage power supply; Rs: waveform forming resistance; Rc: charging resistance
Rm: impedance matching resistor; Cc: energy storage capacitor
The basic requirements for electrical fast transient pulse clusters are:
The rising time of the pulse (10% ~ 90%): 5 ns% 30;
Pulse duration (50% of rising edge to 50% of falling edge): 50ns 30%;
Pulse repetition frequency: 5kHz or 100kHz；;
Duration of the pulse: 15ms；;
The repetition period of the pulse: 300ms；;
Open circuit output voltage (peak value) of the generator: (0.25 ~ 4) kV;
Dynamic output impedance of the generator: 50 Ω 20%;
The polarity of the pulse: positive/negative;
Relationship with power supply: asynchronous.
Electrical fast transient pulse group test coolness rating
