Showing papers on "Impulse generator published in 1973"

Circuit for generating a single high voltage subnanosecond pulse from a step recovery diode

Abstract: A series connected electronic circuit including in combination a trigger generator, an impulse generator, a filter circuit having an inductance L, a step recovery diode having a forward resistance RF and a reverse capacitance CR and an optimal bias circuit coupled to the step recovery diode. The trigger generator produces a train of pulses having a relatively long time interval, T, between each pulse; these pulses are then coupled to the impulse generator which produces an impulse having a Fourier component predominant at a frequency omega in response to each trigger pulse. The filter circuit converts each impulse into a damped sine wave having an angular frequency omega and a damping constant delta RF/2L. The sine wave is coupled to the step recovery diode which generates a single high voltage subnanosecond pulse having a half period, tp/ pi square root LCR in response to each damped sine wave.

Prediction of the parameters of an impulse generator for transformer testing

Abstract: Simple expressions have been developed by which it is possible to predict the parameters of an impulse generator required to produce the standard lightning-impulse waveshape for the testing of transformers. The formulas also help to determine the limiting testing capability of a given generator. A simple method of extending the testing capability of a given resistance-front-control generator is also proposed.

Impulse generator to ignite combustion engines

Abstract: An impulse generator for igniting combustion engines has an electronic circuit installed between the breaker points and the high voltage coil thereof. A first transistor has its emitter connected to the coil and its base connected to the points so that closing of the points causes actuation of the first transistor. The collector of the first transistor passes electric current through an electrolytic condenser to actuate a second transistor, thereby feeding the primary of the coil so that when the points open, the collector of the first transistor loses voltage and interrupts the collector-emitter passage of the second transistor to originate high voltage in the secondary coil. When high voltage occurs in the coil, there is an inverse damping oscillation in the collector of the second transistor which is channelled toward a condenser and resistor, shunt-connected to the collector of the second transistor from where current is transmitted to the base of the first transistor which it actuates, and the cycle is begun again.

The Effect of A.C. Bias Fields on the Impulse Strength of Point-Plane and Sphere-Plane Gaps

Abstract: Present laboratory impulse tests do not simulate the large power-frequency voltages which may be present in practice. Experiments up to 850 kV (impulse) show that such bias fields have no significant effect on impulse breakdown. The 50% breakdown strength for both fast "lightning" impulses (1.7 As rise time) and for slower "switching" impulses (80O?s rise time) was measured on 1.75 m point-plane and sphere-plane gaps with bias voltages from zero up to 200 kV r.m.s. and at various points-on-wave. A laser triggered gap was used to protect the impulse generator from the power frequency voltage.

Device for providing a current supply to inductive loads by use of a battery and a d. c. pulse transformer positioned between battery and load

Abstract: A device for controlling the current supply to inductive loads through the use of a battery and d.c. pulse transformers associated with each load. Each of the d.c. pulse transformers are controlled from a central impulse generator so that at least the energization point of each of the d.c. pulse transformers are always shifted with respect to those of the remaining d.c. pulse transformers. The d.c. pulse transformers are conventional and can be controlled by the impulse generator for time shifting each at a predesignated time in the period so that the return energy from one load is absorbed by a different load.