EMC control for pulsed high voltage source of a plasma device for medical treatment

1. A high voltage source to be coupled to an electrode arrangement for dielectric barrier discharge plasma treatment of living tissue, the high voltage source comprising:

a high voltage transformer device including a primary inductor and a secondary inductor that are coupled via a magnetic circuit; wherein the secondary inductor is to be coupled to the electrode arrangement;

a feed circuit including a power capacitor, wherein the power capacitor is coupled with the primary inductor and a first controllable conductor in series to:

provide a pulsed primary current in the primary inductor resonating with the capacitor when the first controllable conductor is switched in a conducting on-state; and

feed the power capacitor with electrical current when the first controllable conductor is switched in a non-conducting off-state;

a controller arranged to cause an intermittent switching of the first controllable conductor between the on-state and the off-state; and

a second controllable conductor coupled in parallel to the primary inductor;

wherein the controller is arranged to switch the second controllable conductor to a conducting on-state, when the first controllable conductor is in an on-state, to short circuit a resonating current in the primary inductor, and

wherein the second controllable conductor comprises a silicon controlled rectifier having a gate that is coupled via an inductor to a controller circuit, the controller circuit being magnetically coupled to the inductor.

2. The high voltage source of claim 1 , wherein the second controllable conductor comprises a control terminal that is galvanically disconnected from the primary inductor.

3. The high voltage source of claim 1 , wherein the controller is arranged to cause a switching of the second controllable conductor to a conducting on-state, wherein the switch occurs within a timeframe ranging from 5-50 microseconds when the first controllable conductor is switched into an on-state.

4. The high voltage source of claim 1 , wherein the feed circuit includes a power source, an inductor and a unidirectional current conductor coupled in series to the power capacitor, for feeding electrical current into the power capacitor.

5. The high voltage source of claim 1 , wherein the first controllable conductor is bidirectional.

6. The high voltage source of claim 1 , wherein the second controllable conductor is unidirectional.

7. The high voltage source according to claim 1 , wherein the controller drives the high voltage transformer to a pulsed voltage in a range of 3-8 kV, repetition rate in a range of 0.5-100 kHz, and a pulse duration in a range of 1 nano-150 micro second.

8. An arrangement including a high voltage source, coupled to an electrode arrangement,

wherein the high voltage source comprises:

a high voltage transformer device including a primary inductor and a secondary inductor that are coupled via a magnetic circuit; wherein the secondary inductor is to be coupled to the electrode arrangement;

a feed circuit including a power capacitor, wherein the power capacitor is coupled with the primary inductor and a first controllable conductor in series to:

provide a pulsed primary current in the primary inductor resonating with the capacitor when the first controllable conductor is switched in a conducting on-state; and

feed the power capacitor with electrical current when the first controllable conductor is switched in a non-conducting off-state;

a controller arranged to cause an intermittent switching of the first controllable conductor between the on-state and the off-state; and

a second controllable conductor coupled in parallel to the primary inductor;

wherein the controller is arranged to switch the second controllable conductor to a conducting on-state, when the first controllable conductor is in an on-state, to short circuit a resonating current in the primary inductor, and

wherein the second controllable conductor comprises a silicon controlled rectifier having a gate that is coupled via an inductor to a controller circuit, the controller circuit being magnetically coupled to the inductor; and

wherein said electrode arrangement comprises:

a first electrode to be coupled to the high voltage source via a first lead;

a dielectric is formed by a flexible material in such a way that the dielectric shields the first planar electrode from the surface to be treated; and

a spacer defining a structured surface on a side of said arrangement facing a surface to be treated,

wherein the first electrode is fitted to an object to be treated and brought in contact with the dielectric.

9. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the first lead connects to a high voltage clamp, and wherein the second lead connects to a reference voltage clamp.

10. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the first electrode is a stretchable mesh.

11. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the second controllable conductor comprises a control terminal that is galvanically disconnected from the primary inductor.

12. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the controller is arranged to cause a switching of the second controllable conductor to a conducting on-state, wherein the switch occurs within a timeframe ranging from 5-50 microseconds when the first controllable conductor is switched into an on-state.

13. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the feed circuit includes a power source, an inductor and a unidirectional current conductor coupled in series to the power capacitor, for feeding electrical current into the power capacitor.

14. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the first controllable conductor is bidirectional.

15. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the second controllable conductor is unidirectional.

16. The arrangement including a high voltage source, coupled to an electrode arrangement of claim 8 , wherein the controller drives the high voltage transformer to a pulsed voltage in a range of 3-8 kV, repetition rate in a range of 0.5-100 kHz, and a pulse duration in a range of 1 nano-150 micro second.