High voltage pre-pulsing
Some embodiments of the invention include a pre-pulse switching system. The pre-pulsing switching system may include: a power source configured to provide a voltage greater than 100 V; a pre-pulse switch coupled with the power source and configured to provide a pre-pulse having a pulse width of T pp ; and a main switch coupled with the power source and configured to provide a main pulse such that an output pulse comprises a single pulse with negligible ringing. The pre-pulse may be provided to a load by closing the pre-pulse switch while the main switch is open. The main pulse may be provided to the load by closing the main switch after a delay T delay after the pre-pulse switch has been opened.
1. A pre-pulse switching calibration method comprising:
providing a pre-pulse with a pulse width T pp to a load;
providing a main pulse to the load after a delay T delay , and the main pulse has an output voltage V out ;
adjusting the pulse width of the pre-pulse T pp ; and
adjusting the delay T delay until the pre-pulse and the main pulse merge into a single pulse at the load.
2. The method according to claim 1 , wherein the pulse width T pp is less than 1,000 ns.
3. The method according to claim 1 , wherein the delay T delay is less than 1,000 ns.
4. The method according to claim 1 , wherein adjusting the delay T delay until the pre-pulse and the main pulse merge into a single pulse at the load further comprising incrementing the delay T delay by a factor of less than T delay /10.
5. The method according to claim 1 , wherein adjusting the pulse width of the pre-pulse T pp , further comprises:
determining that the voltage at the load from the pre-pulse is less than the output voltage; and
increasing the pulse width of the pre-pulse T pp .
6. The method according to claim 1 , wherein adjusting the pulse width of the pre-pulse T pp , further comprises:
determining that the voltage at the load has a dip due to T delay being too long; and
decreasing the width of T delay .
7. The method according to claim 1 , wherein the delay T delay is less than the pulse width of T pp .
8. The method according to claim 1 , wherein the output voltage V out is greater than 100 V.
9. The method according to claim 1 , wherein the pre-pulse has a rise time less than about 500 ns.
10. A pre-pulse switching system comprising:
a power source configured to provide a voltage greater than 100 V;
a pre-pulse switch coupled with the power source and configured to provide a pre-pulse to a load having a pulse width of T pp ; and
a main switch coupled with the power source and configured to provide a main pulse to the load;
wherein the pre-pulse and the main pulse are merged into a single output pulse with negligible ringing;
wherein the pre-pulse is provided to the load by closing the pre-pulse switch while the main switch is open;
wherein the main pulse is provided to the load by closing the main switch after a delay T delay after the pre-pulse switch has been opened.
11. The pre-pulse switching system according to claim 10 , wherein the pre-pulse has a rise time less than 500 ns.
12. The pre-pulse switching system according to claim 10 , further comprising a rectified output.
13. The pre-pulse switching system according to claim 10 , further comprising an H-bridge switching topology.
14. The pre-pulse switching system according to claim 10 , wherein the stray inductance of the pre-pulse switching system is less than about 1000 nH.
15. The pre-pulse switching system according to claim 10 , wherein the stray capacitance of the pre-pulse switching system is less than about 1000 nF.
16. The pre-pulse switching system according to claim 10 , wherein either or both the main switch and the pre-pulse switch comprise a solid-state switch.
17. A switching system comprising:
a high voltage power supply;
an output;
a plurality of pre-pulse switches coupled with the high voltage power supply, each of the plurality of pre-pulses are configured to provide a pre-pulse to the output having a pulse width T pp ; and
a plurality of main switches coupled with the power supply, each of the plurality of main switches are configured to provide a main pulse to the output with a voltage greater than 100 V, wherein an output pulse comprises a single output pulse from the combination of the pre-pulse and the main pulse switches with a pulse length greater than 10 ns;
wherein each of the main pulses are provided after a delay from the plurality of pre-pulse switches providing the plurality of pre-pulses.
18. The switching system according to claim 17 , wherein the output pulse has negligible ringing.
19. The switching system according to claim 17 , wherein the plurality of pre-pulse switches and the plurality of main switches are arranged in an H-bridge topology.
20. The switching system according to claim 17 , wherein the pre-pulse has a rise time less than 500 ns.
21. The switching system according to claim 17 , further comprising a transformer coupled output.