High voltage nanosecond pulser with variable pulse width and pulse repetition frequency
A nanosecond pulser is disclosed. In some embodiments, the nanosecond pulser may include one or more switch circuits including one or more solid state switches, a transformer, and an output. In some embodiments, the transformer may include a first transformer core, a first primary winding wound at least partially around a portion of the first transformer core, and a secondary winding wound at least partially around a portion of the first transformer core. In some embodiments, each of the one or more switch circuits are coupled with at least a portion of the first primary winding. In some embodiments, the output may be electrically coupled with the secondary winding and outputs electrical pulses having a peak voltage greater than about 1 kilovolt and a rise time of less than 150 nanoseconds or less than 50 nanoseconds.
1. A digital pulser comprising:
a fast capacitor;
a switch circuit electrically coupled with the fast capacitor;
a transformer comprising:
a transformer core;
a primary winding wound at least partially around a portion of the transformer core, the switch circuit is coupled with at least a portion of the primary winding; and
a secondary winding wound at least partially around a portion of the transformer core; and
an output electrically coupled with the secondary winding that outputs electrical pulses having a peak voltage greater than about 1 kilovolt and a rise time of less than 150 nanoseconds;
wherein less than 50% of the energy stored within the fast capacitor is discharged to the transformer during a switch cycle.
2. The digital pulser of claim 1 , wherein the electrical pulses have an output pulse width that is variable and proportional to an input pulse width.
3. The digital pulser of claim 1 , wherein the electrical pulses have a pulse repetition frequency greater than 1 kHz.
4. The digital pulser of claim 1 , wherein the switch comprises one or more solid state switches, IGBTs, FETs, MOSFETs, or a SiC junction transistor.
5. The digital pulser of claim 1 , wherein less than 25% of the energy stored within the fast capacitor is discharged to the transformer during a switch cycle when the switch is closed.
6. The digital pulser of claim 1 , further comprising stray inductance between the fast capacitor and the switch is less than 50 nH.
7. The digital pulser of claim 1 , wherein further comprising stray inductance between the switch and the transformer is less than 50 nH.
8. The digital pulser of claim 1 , wherein the fast capacitor has a capacitance between about 1 μF and about 5 μF.
9. The digital pulser of claim 1 , wherein the fast capacitor has a capacitance between about 100 nF and about 1,000 nF.
10. A digital pulser comprising:
an energy storage capacitor having a capacitance between about 100 nF and about 1,000 nF;
a switch circuit electrically coupled with the fast capacitor, the switch circuit comprises a switch selected from the group consisting of an IGBT, an FET, a MOSFET, and an SiC junction transistor; and
an output electrically or inductively coupled with the switch circuit that outputs electrical pulses having a peak voltage greater than about 1 kilovolt and a rise time of less than 150 nanoseconds and a pulse repetition greater than 10 kHz;
wherein less than 50% of the energy stored within the fast capacitor is discharged to the transformer during a switch cycle.
11. The digital pulser of claim 10 , further comprising a transformer comprising:
a transformer core;
a primary winding wound at least partially around a portion of the transformer core, the switch circuit is coupled with at least a portion of the primary winding; and
a secondary winding wound at least partially around a portion of the transformer core, the output is coupled with the secondary winding.
12. The digital pulser of claim 10 , wherein less than 25% of the energy stored within the fast capacitor is discharged to the transformer during a switch cycle when the switch is closed.
13. The digital pulser of claim 10 , further comprising stray inductance between the fast capacitor and the switch is less than 50 nH.
14. The digital pulser of claim 10 , wherein further comprising stray inductance between the switch and the transformer is less than 50 nH.
15. The digital pulser of claim 10 , wherein the electrical pulses have an output pulse width that is variable and proportional to an input pulse width.
16. A digital pulser comprising:
an energy storage capacitor having a capacitance between about 1 μF and about 5 μF;
a switch circuit electrically coupled with the fast capacitor, the switch circuit comprises a switch selected from the group consisting of an IGBT, an FET, a MOSFET, and an SiC junction transistor; and
an output electrically or inductively coupled with the switch circuit that outputs electrical pulses having a peak voltage greater than about 1 kilovolt and a rise time of less than 150 nanoseconds and a pulse repetition greater than 10 kHz;
wherein less than 50% of the energy stored within the fast capacitor is discharged to the transformer during a switch cycle.
17. The digital pulser of claim 16 , wherein less than 25% of the energy stored within the fast capacitor is discharged to the transformer during a switch cycle when the switch is closed.
18. The digital pulser of claim 16 , further comprising stray inductance between the fast capacitor and the switch is less than 50 nH.
19. The digital pulser of claim 16 , wherein further comprising stray inductance between the switch and the transformer is less than 50 nH.
20. The digital pulser of claim 16 , wherein the electrical pulses have an output pulse width that is variable and proportional to an input pulse width.