Efficient nanosecond pulser with source and sink capability for plasma control applications
Some embodiments include a high voltage, high frequency switching circuit. In some embodiments, the high voltage, high frequency switching circuit includes a high voltage switching power supply that produces pulses having a voltage greater than 1 kV and with frequencies greater than 10 kHz; a transformer having a primary side and secondary side; an output electrically coupled with the secondary side of the transformer; and a primary sink electrically coupled with the primary side of the transformer and in parallel with the high voltage switching power supply, the primary sink comprising at least one resistor that discharges a load coupled with the output.
1. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage between 1 kV and 100 kV and with frequencies between 10 kHz and 1 MHz;
a transformer having a primary side including a primary winding and a secondary side including a secondary winding;
an output electrically coupled with the secondary side of the transformer, wherein the output is coupled with a plasma load that is capacitive in nature; and
a primary sink electrically coupled with both the primary side of the transformer and the output and ground, the primary sink comprising at least one resistor that discharges the plasma load coupled with the output.
2. The high voltage, high frequency switching circuit according to claim 1 , wherein the primary sink is configured to dissipate over about 1 kilowatt of average power.
3. The high voltage, high frequency switching circuit according to claim 1 , wherein the primary sink further comprises at least one inductor in series with the at least one resistor.
4. The high voltage, high frequency switching circuit according to claim 1 , wherein the primary sink further comprises a switch in series with the at least one resistor.
5. The high voltage, high frequency switching circuit according to claim 1 , wherein the plasma load includes a dielectric barrier discharge.
6. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistor in the primary sink has a resistance value less than about 400 ohms.
7. The high voltage, high frequency switching circuit according to claim 1 , wherein the high voltage high frequency switching power supply delivers peak powers greater than 100 kW.
8. The high voltage, high frequency switching circuit according to claim 1 , wherein the resistor in the primary sink includes a resistance R in ohms and the output is coupled with the plasma load having a capacitance C in Faradays such that
R
≈
t
f
a
2
C
where t f is the pulse fall time in seconds, where a is the ratio of the number of turns of the primary winding and the number of turns of the secondary winding.
9. The high voltage, high frequency switching circuit according to claim 1 , wherein the plasma load has a capacitance less than 50 nF, wherein the plasma load capacitance does not hold charges for times greater than 10 μs.
10. The high voltage, high frequency switching circuit according to claim 1 , wherein the high voltage, high frequency switching circuit rapidly charges the plasma load capacitance and discharges the plasma load capacitance.
11. The high voltage, high frequency switching circuit according to claim 1 , wherein the output produces a negative bias voltage within the plasma load of greater than −2 kV when the high voltage switching power supply is not providing a high voltage pulse.
12. The high voltage, high frequency switching circuit according to claim 11 , wherein the primary sink further includes an inductor coupled to the at least one resistor, and wherein the inductance L (in Henries) of the inductor and the resistance R (in Ohms) of the resistor are set to satisfy L/R≈tp, where tp is the pulse width of the pulse in seconds.
13. The high voltage, high frequency switching circuit according to claim 11 , wherein the at least one resistor in the primary sink includes a resistance R, in Ohms, and the output is coupled with the plasma load having a capacitance C, in Faradays, such that
R
≈
t
f
a
2
C
where t f is the pulse fall time, in seconds wherein a is the ratio of the number of turns of the primary winding and the number of turns of the secondary winding.
14. The high voltage, high frequency switching circuit according to claim 1 , wherein the output can produce a high voltage pulse having a voltage greater than 1 kV and with frequencies greater than 10 kHz with pulse fall times less than about 400 ns.
15. The high voltage, high frequency switching circuit according to claim 1 , wherein the high voltage switching power supply comprises a power supply, at least one switch, and a step-up transformer.
16. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage between 1 kV and 100 kV and with frequencies between 10 kHz and 1 MHz, wherein the high voltage switching power supply comprises a power supply, at least one switch, and a step-up transformer;
a transformer having a primary side and a secondary side;
an output electrically coupled with the secondary side of the transformer; and
a primary sink electrically coupled to both the primary side of the transformer and the output and ground, the primary sink comprising at least one resistor that discharges a load coupled with the output and at least one inductor in series with the at least one resistor.
17. The high voltage, high frequency switching circuit according to claim 16 , wherein the primary sink further comprises a switch in series with one inductor.
18. The high voltage, high frequency switching circuit according to claim 16 , wherein the output can produce a high voltage pulse having a voltage greater than 1 kV and with frequencies greater than 10 kHz and with a pulse fall time less than about 400 ns.
19. The high voltage, high frequency switching circuit according to claim 16 , wherein the primary sink is configured to dissipate over about 1 kilowatt of power.
20. The high voltage, high frequency switching circuit according to claim 16 , wherein the primary sink handles a peak power greater than 10 kW.
21. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage between 1 kV and 100 kV and with frequencies between 10 kHz and 1 MHz;
a transformer having a primary side and a secondary side;
an output electrically coupled with the secondary side of the transformer; and
a primary sink electrically coupled to both the primary side of the transformer, the output, and ground, the primary sink comprising at least one resistor that discharges a load coupled with the output and at least one inductor in series with the at least one resistor, wherein the primary sink is configured to dissipate over about 1 kilowatt of power.
22. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage between 1 kV and 100 kV and with frequencies between 10 kHz and 1 MHz;
a transformer having a primary side and a secondary side;
an output electrically coupled with the secondary side of the transformer; and
a primary sink electrically coupled to both the primary side of the transformer, the output, and ground, the primary sink comprising at least one resistor that discharges a load coupled with the output and an inductor coupled to the at least one resistor, wherein the inductance L of the inductor, in Henries, and the resistance R of the resistor, in Ohms, are set to satisfy L/R≈tp, where tp is the pulse width of the pulse, in seconds.
23. A high voltage, high frequency switching circuit comprising:
a high voltage switching power supply that produces pulses having a voltage between 1 kV and 100 kV and with frequencies between 10 kHz and 1 MHz;
a transformer having a primary side including a primary winding and a secondary side including a secondary winding;
an output electrically coupled with the secondary side of the transformer; and
a primary sink electrically coupled to both the primary side of the transformer, the output, and ground, the primary sink comprising at least one resistor that discharges a load coupled with the output and at least one inductor in series with the at least one resistor, wherein the at least one resistor in the primary sink includes a resistance R, in Ohms, and the output is coupled with the load having a capacitance C, in Faradays, such that
R
≈
t
f
a
2
C
where t f is the pulse fall time, in seconds wherein a is the ratio of the number of turns of the primary winding and the number of turns of the secondary winding.