CN211409334U - Electric pulse device for treating tumors - Google Patents

Abstract

The present disclosure relates to an electrical pulse device for treating tumors. The apparatus includes a DC power supply, a conversion circuit, and a control circuit. The conversion circuit is coupled to the dc power source and is operable to convert a dc voltage from the dc voltage to a bipolar pulse voltage. The conversion circuit comprises a driving circuit, a first inversion branch circuit and a second inversion branch circuit connected with the first inversion branch circuit in parallel. The first inversion branch comprises a first IGBT and a second IGBT which are connected in series. The second inverting branch includes a third IGBT and a fourth IGBT 4. The control circuit is coupled to the conversion circuit and is operable to cause the drive circuit to alternately apply a first pair of positive and negative drive signals to the first and second IGBTs and a second pair of positive and negative drive signals to the third and fourth IGBTs to cause the conversion circuit to generate the bipolar pulse voltage. By using an electrical pulse device according to the present disclosure, the device lifetime can be extended and possible medical accidents prevented.

Description

Electric pulse device for treating tumors

Technical Field

The present disclosure relates to the field of electronics, and more particularly to electronic medical devices.

Background

Tumors, especially malignant tumors, are major diseases that endanger human health. Traditional and more recently developed therapies for tumors are thermal ablation physiotherapy characterized by minimally invasive ablation. The clinical application of the traditional Chinese medicine composition has certain limitations due to the limitation of factors such as indications, contraindications, side effects of treatment, heat effect and the like. In recent years, with the continuous development of pulsed bioelectricity, the electric field pulse attracts the attention of researchers due to the non-thermal and minimally invasive biomedical effects thereof, and the irreversible electroporation therapy of tumors among them attracts the extensive attention of researchers in the bioelectricity field at home and abroad due to the advantages and characteristics of rapidness, controllability, visibility, selectivity, non-thermal mechanism and the like, and is gradually applied to the clinical treatment of tumors.

Conventional devices for treating tumors output pulses that are unipolar pulses. When the unipolar pulse acts on human tissues, muscle contraction is easily caused, the pain of a patient is increased, the treatment difficulty is increased, and the electric field of the unipolar pulse is uneven and has an ablation blind area, so that the ablation effect is not good.

Furthermore, conventional devices for treating tumors also present the risk of short device life and medical accidents due to the output of undesired electrical pulses.

SUMMERY OF THE UTILITY MODEL

According to an embodiment of the present disclosure, an improved apparatus for treating a tumor is provided.

In one aspect of the present disclosure, an electrical pulse device for treating a tumor is provided. The apparatus includes a DC power supply and a conversion circuit. The conversion circuit is coupled to the dc power source and is operable to convert a dc voltage from the dc voltage to a bipolar pulse voltage. The conversion circuit comprises a driving circuit, a first inversion branch circuit and a second inversion branch circuit connected with the first inversion branch circuit in parallel. The first inverting branch comprises a first Insulated Gate Bipolar Transistor (IGBT) and a second IGBT which are connected in series. The second inversion branch comprises a third IGBT and a fourth IGBT which are connected in series. The drive circuit is operable to alternately apply a first pair of positive and negative drive signals to the first and second IGBTs, and a second pair of positive and negative drive signals to the third and fourth IGBTs, such that the conversion circuit generates a bipolar pulse voltage. By using an electrical pulse device according to the present disclosure, the device lifetime can be extended and possible medical accidents prevented.

It should be understood that what is described in this summary section is not intended to limit key or critical features of the embodiments of the disclosure, nor is it intended to limit the scope of the disclosure. Other features of the present disclosure will become apparent from the following description.

Drawings

The above and other features, advantages and aspects of various embodiments of the present disclosure will become more apparent by referring to the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, like or similar reference characters designate like or similar elements, and wherein:

FIG. 1 illustrates a schematic diagram of an example environment in which embodiments of the present disclosure may be implemented;

FIG. 2 illustrates a partial schematic view according to an embodiment of the present disclosure;

FIG. 3 shows a conventional pulse signal diagram; and

fig. 4 shows a pulse signal schematic according to an embodiment of the present disclosure.

Detailed Description

Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present disclosure are shown in the drawings, it is to be understood that the present disclosure may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the disclosure are for illustration purposes only and are not intended to limit the scope of the disclosure.

In describing embodiments of the present disclosure, the terms "include" and its derivatives should be interpreted as being inclusive, i.e., "including but not limited to. The term "based on" should be understood as "based at least in part on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first," "second," and the like may refer to different or the same object. Other explicit and implicit definitions are also possible below.

Generally, electrical pulse devices used to treat tumors typically use unipolar pulses to irreversibly destroy tumor tissue. The voltage for application to the tumour tissue is typically a high voltage pulse such as 3000V and the value of the applied voltage and the frequency of the pulse may be selected accordingly based on the type of tumour being targeted, shape, size, malignancy and the like.

However, the conventional electric pulse device for treating tumor has problems of over-treatment, non-ideal treatment effect, even treatment accident, and the like. The inventor finds out through research that the electric pulse signal output by the conventional electric pulse device has a spike waveform at the pulse edge, for example, see fig. 3. For devices used to treat tumors, these spiking waveforms cause the electrical pulse device to output a voltage that exceeds a predetermined value. For treatment voltages up to thousands of volts, these spikes may cause the peak voltage to exceed a predetermined value by more than a few hundred volts, which may lead to undesirable treatment effects and, in severe cases, may even cause medical accidents such as irreversible destruction of normal tissue.

Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings. Fig. 1 illustrates a schematic diagram of an example environment 100 in which embodiments of the present disclosure may be implemented. An example environment 100 is shown as an electrical pulse device 100 for treating a tumor.

The electric pulse equipment 100 comprises an upper computer 2, a control circuit 4, a high-voltage direct-current power supply 6, a conversion circuit 8, a switching board 10, electrode needles 22 and 24, an auxiliary circuit and the like. While a number of components or circuits are schematically shown in fig. 1, it will be understood that this is merely illustrative and not a limitation on the scope of the disclosure. For example, in the embodiment of FIG. 1, some other components may be added between various components, or some components may be subtracted from the embodiment of FIG. 1.

The upper computer 2 may be a computing device such as a computer and a tablet computer. In some examples, the upper computer 2 may include only a display screen and an input device. In still other examples, the host computer may include only the input device.

The control circuit 4 may comprise a CPU or an ARM processor. In some examples, the control circuit 4 may also be referred to as a lower circuit board or a lower board opposite the upper computer 2. The control circuitry 4 can be coupled to the various components in the electrical pulse device 100 in a wired or wireless manner as desired to receive, process, and transmit data signals to effect control of the various components in the electrical pulse device 100.

The high voltage dc power supply 6 may generate the required dc voltage based on a signal from the control circuit 4. For example, the high voltage dc power supply 6 may convert a 220V ac mains voltage into a 800V to 3000V dc voltage based on a signal from the control circuit 4. In other examples, the high voltage direct current power supply 6 may convert the ac mains voltage to a dc voltage below 800V, such as 300V, 400V, 500V, 600V or 700V, or to a dc voltage above 3000V, such as 3100V, 3300V, 3500V, 3700V or 4000V.

The conversion circuit 8 may convert the direct-current voltage from the high-voltage direct-current power supply 6 into a pulse voltage based on a signal from the control circuit 4. In one example, the pulsed voltage is a bipolar pulsed voltage. By using the bipolar pulse voltage, the problems of non-uniform electric field, ablation blind area, poor ablation effect and the like caused by unipolar pulse voltage can be solved, and the problems of muscular atrophy, treatment pain and the like can be avoided.

For example, the pulse voltage may be a bipolar pulse voltage having an amplitude of 800V and a frequency of 100 Hz. In another example, the pulsed voltage may be a bipolar pulsed voltage with an amplitude of 3000V and a frequency of 1000 Hz. In one example, a storage capacitor C1 may be provided between the conversion circuit 8 and the high voltage dc power supply 6 to facilitate the conversion circuit 8 obtaining stable power.

Although two specific bipolar pulse voltages are schematically illustrated above, it will be understood that this is merely illustrative and not limiting on the scope of the present disclosure. For example, the amplitude and frequency of the bipolar pulse voltage may be selected based on the type, shape, size, malignancy of the tumor being targeted, and the like.

The switch board 10 is coupled to the conversion circuit 8 and the control circuit 4 via a load resistance R2, and selectively switches the pulse voltage between the electrode pins 22 and 24 according to a control signal of the control circuit 4. Paddle 10 includes a first plate 102 and a second plate 104. Different potentials are applied between the first plate 102 and the second plate 104, thereby forming a voltage between the two. The direction between the first plate 102 and the second plate 104 may be reversed as desired with the pulse waveform.

The switchboard 10 comprises a first switch 106 and a second switch 108. The first switch 106 and the second switch 108 are coupled to the control circuit 4 and are controlled by the control circuit 4. In one example, the first switch 106 and the second switch 108 may be relays. By connecting the first switch 106 and the second switch 108 to plates having different potentials, a high voltage electric field can be formed between the electrode needles 22 and 24.

Although only two electrode needles are shown in the embodiment of fig. 1, it is to be understood that this is an example only and is not limiting to the scope of the present disclosure. More electrode needles, e.g. 4 electrode needles, may be selected based on the type of tumor to be targeted, shape, size, malignancy, etc., including two electrode needles with a high potential and two electrode needles with a low potential. In another example, 5, 7 or 8 electrode needles may be selected and the potential of each electrode needle may be different.

In the embodiment of fig. 1, the electrical pulse device 100 also has a bleed resistor R1. A bleed resistor R1 is coupled between the high voltage dc power supply 6 and the conversion circuit 8 and is operable to bleed off accumulated energy in the event of an emergency stop. During operation of the electric pulse apparatus 100, a doctor or a user may need to perform an emergency stop operation, i.e., an emergency stop, on the electric pulse apparatus 100 having a high voltage electricity because of an emergency.

Thus, in one embodiment of the present disclosure, the electric pulse device 100 also has an emergency stop switching means. The scram switch device may include, for example, a first switch S1, a second switch S2, a third switch S3, and a fourth switch S4. The emergency stop switching device is coupled to the high voltage dc power source through a fourth switch S4, to the bleeder resistor through a first switch S1, and to the conversion circuit 8 through a second switch S2 and a third switch S4.

The scram switch device is operable to open the electrical connection of the high voltage dc power source 6 to the conversion circuit 8 by opening the second switch S2 and the third switch S3, close the high voltage dc power source 6 by closing the fourth switch S4, and open the discharging resistor R1 to discharge energy by closing the first switch S1 in response to the scram switch being turned on (e.g., a mechanical button being pressed). In one example, the discharging resistor R1 may be turned on to discharge the energy by closing the first switch S1 after a certain period of time after turning off the high voltage dc power supply 6.

In the example of fig. 1, electrical pulse device 100 further includes footswitch S5 coupled between switch board 10 and switching circuit 8. When a doctor or a user uses the electric pulse therapy apparatus, it is not desirable that the electric field is always applied to the electrode needle, but is applied only at the time of therapy. In some examples, it is not desirable that the electrode needle always apply the electric field, even while treating, but only when the electrode needle is in place (e.g., inserted at a particular location within human tissue). Therefore, a switch is required to control the application of the electric field. Compared with the conventional hand-pressed switch, the foot switch S5 can prevent the doctor from touching the switch with hands during treatment to cause bacteria contamination, thereby avoiding infection risk to the wound. In addition, by using the foot switch S5, the doctor does not need to control the switch by a layman, making the treatment more convenient.

Fig. 2 shows a partial schematic view according to an embodiment of the present disclosure. For ease of understanding and description, some of the components in fig. 1 are not shown here to avoid affecting the description of the important components. This does not mean that some of the components in fig. 1 are not present or may be omitted in the embodiment of fig. 2.

The high voltage DC power supply 6 supplies DC voltage V to the conversion circuit 8_A. The conversion circuit 8 includes a drive circuit 80 and an inverter circuit. The inverter circuit comprises a first inverter branch and a second inverter branch. The first inverting branch comprises a high voltage terminal V_AAnd a ground voltage terminal V_BA first IGBT S1 and a second IGBT S2 coupled in series therebetween, the second inverting branch including a first terminal V at a high voltage_AAnd a ground voltage terminal V_BA third IGBT S3 and a fourth IGBT S4 coupled in series therebetween.

The control circuit 4 sends a control signal to the drive circuit 80 so that the drive circuit 80 controls the on and off of the IGBTs in the inverter circuit. For example, at one time, the driving circuit 80 turns on the first IGBT S1 and the fourth IGBT S4, and turns off the second IGBT S2 and the third IGBT S3, so that the first plate of the switching plate 10 is applied with a high voltage, and the first plate of the switching plate 10 is applied with a low voltage. At the next moment, the drive circuit turns on the second IGBT S2 and the third IGBT S3, and turns off the first IGBT S1 and the fourth IGBT S4, so that the first plate of the switching plate 10 is applied with a low voltage, and the first plate of the switching plate 10 is applied with a high voltage.

However, the present inventors found through studies that there is a case where the upper IGBT and the lower IGBT are simultaneously turned on for a short time at the time of switching the IGBTs. For example, the first IGBT S1 and the second IGBT S2 are turned on simultaneously, which causes a short circuit situation in the first inverting branch. This is because the parasitic capacitance between the gate and collector of the IGBT produces a high transient voltage change (dv/dt) during the turn-off of the IGBT, which causes the voltage between the gate and collector to increase, turning on the IGBT.

Although the short circuit is short in time, the waveform output by the electrode needle still has the phenomenon of burrs or spikes. A conventional pulse signal diagram of this type is shown, for example, in fig. 3. It can be seen in fig. 3 that at the beginning of a pulse transition there is a small pulse spike. This small pulse spike can be hundreds or even thousands of volts in the case of high voltage applications such as electrical pulse tumor therapy devices. Such an undesirably high pressure may cause the normal cells to be irreversibly damaged.

In addition, in the case of the electric pulse therapeutic apparatus, since the upper and lower IGBTs are simultaneously turned on to form a short circuit, the short circuit generates considerable heat, thereby affecting the life span of the inverter circuit. In severe cases, the short circuit may even cause the IGBT to collapse and not continue to function.

In view of the above problem, in one embodiment of the present disclosure, the driving circuit 80 alternately applies a first pair of positive and negative driving signals to the first IGBT S1 and the second IGBT S2, and a second pair of positive and negative driving signals to the third IGBT S3 and the fourth IGBT S4 in response to the control signal of the control circuit 4, so that the conversion circuit generates the bipolar pulse voltage.

For example, at one time, the driver circuit 80 provides a voltage of +15V to the first IGBTS1, a voltage of-5V to the second IGBT S2, a voltage of-5V to the third IGBTS3, and a voltage of +15V to the fourth IGBTS 4. At the next time of the pulse signal transition, the driving circuit 80 supplies a voltage of-5V to the first IGBT S1, a voltage of +15V to the second IGBT S2, a voltage of +15V to the third IGBT S3, and a voltage of-5V to the fourth IGBT S4, and thus alternately reciprocates.

Although +15V and-5V are used as examples for illustration above, this is merely illustrative and not limiting of the scope of the disclosure. In one example, the positive drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to +18V, and the negative drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to-8V.

In another example, the positive drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to +15V, and the negative drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to-5V.

In yet another example, the positive drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to +15V, and the negative drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to-8V.

In yet another example, the positive drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to +18V, and the negative drive signal of the first pair of positive and negative drive signals is selected from a range from 0V to-5V.

By applying paired positive and negative driving signals to the inversion branch, the short circuit problem caused by instantaneous simultaneous conduction of the upper IGBT and the lower IGBT can be effectively prevented, and the pulse waveform output by the electrode needle is correspondingly more ideal. For example, as shown in fig. 4, the pulse waveform is smooth and complete without any transient spikes or spikes.

Although in the embodiments of the present disclosure, pairs of positive and negative driving signals are applied to the inverting branches to prevent the occurrence of short-circuit problems due to instantaneous simultaneous conduction of the upper and lower IGBTs, it is understood that this is only an example and not a limitation on the scope of the present disclosure. In other examples, the short circuit problem caused by instantaneous simultaneous conduction of the upper IGBT and the lower IGBT can be prevented by increasing the gate resistance of the IGBT, the capacitance between the gate and the collector of the IGBT, or providing an additional transistor between the gate and the emitter of the IGBT.

Further, the control circuit 4 is operable to receive a first input indicative of a voltage and adjust the dc power supply based on the received first input to generate an adjusted dc voltage. For example, for a specific kind of tumor, a voltage value can be correspondingly input to the control circuit 4 by the upper computer 2, the control circuit 4 receives the input, and causes the conversion circuit 8 to adjust the value of the bipolar pulse voltage, for example from 1000V to 1500V, based on the received input.

In one example, the conversion circuit 80 further includes a voltage detection device 82. The voltage detection device 82 is operable to detect a dc voltage. Although the conversion circuit 80 is shown in fig. 2 as including the voltage detection device 82, it is to be understood that this is merely illustrative and not a limitation of the scope of the present disclosure. The voltage detection means 82 may be present independently of the conversion circuit 80.

For example, a separate voltage detection device 82 may be provided to detect the direct-current voltage of the emitter and collector of the IGBT, and pass the detected voltage to the control circuit 4. The control circuit 4 is operable to receive the detected direct current voltage, determine that the detected direct current voltage exceeds a threshold, and in response to the detected direct current voltage exceeding the threshold, cause the drive circuit 80 to turn off the first IGBT S1, the second IGBT S2, the third IGBT S3, and the fourth IGBT S4.

For example, when the detected direct-current voltage exceeds the threshold of 7V, the voltage detection device 82 determines that the direct-current voltage exceeds the threshold and that there is a short circuit in this case. The drive circuit 80 turns off the first IGBT S1, the second IGBT S2, the third IGBT S3, and the fourth IGBT S4 to protect the inverter circuit from breakdown.

Although the protection circuit is shown as part of the drive circuit in the example of fig. 2, it is to be understood that this is an example only and not a limitation on the scope of the disclosure. In some other examples, a protection circuit may be separately provided, and when the voltage detection device 82 determines that the direct-current voltage exceeds the threshold and there is a short circuit in this case, the drive circuit 80 causes the separate protection circuit to turn off the first IGBT S1, the second IGBT S2, the third IGBT S3, and the fourth IGBT S4 to protect the inverter circuit from breakdown.

In one example, the control circuit 4 is operable to receive a second input indicative of the frequency and to cause the conversion circuit 8 to adjust the frequency of the bipolar pulse voltage based on the received second input. For example, for a specific kind of tumor, the frequency value may be accordingly input by the upper computer 2 to the control circuit 4, the control circuit 4 receives the input, and based on the received input, causes the conversion circuit 8 to adjust the frequency of the bipolar pulse voltage, for example from 100Hz to 150 Hz.

Electrical pulse devices for treating tumors in accordance with embodiments of the present disclosure are generally described above. Some exemplary embodiments according to the present disclosure are listed below.

Item 1: an electrical pulse apparatus for treating tumors is provided. The electric pulse device comprises a direct current power supply; the conversion circuit is coupled to the direct-current power supply and is operable to convert direct-current voltage from the direct-current voltage into bipolar pulse voltage, the conversion circuit comprises a driving circuit, a first inversion branch and a second inversion branch connected with the first inversion branch in parallel, the first inversion branch comprises a first IGBT and a second IGBT which are connected in series, and the second inversion branch comprises a third IGBT and a fourth IGBT; and a control circuit coupled to the conversion circuit and operable to cause the drive circuit to alternately apply a first pair of positive and negative drive signals to the first and second IGBTs, and to alternately apply a second pair of positive and negative drive signals, opposite the first pair of positive and negative drive signals, to the third and fourth IGBTs4 to cause the conversion circuit to generate a bipolar pulse voltage.

Item 2: the electric pulse device according to item 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range of 0V to +18V, and the negative drive signal of the first pair of positive and negative drive signals is selected from the range of 0V to-8V.

Item 3: the electric pulse device according to item 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to + 15V; and the negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-5V.

Entry 4: the electric pulse device according to item 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to + 15V; and the negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-8V.

Item 5: the electric pulse device according to item 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to + 18V; and the negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-5V.

Item 6: the electric pulse device of clause 1, wherein the control circuit is operable to receive a first input indicative of the voltage and adjust the dc power supply based on the received first input to generate an adjusted dc voltage.

Item 7: the electric pulse device according to item 1, wherein the conversion circuit further comprises voltage detection means operable to detect a direct current voltage.

Entry 8: the electric pulse device of claim 7 wherein the control circuit is operable to: receiving the detected direct current voltage; determining that the detected direct current voltage exceeds a threshold; and causing the drive circuit to turn off the first, second, third, and fourth insulated-gate bipolar transistors in response to the detected direct-current voltage exceeding a threshold.

Item 9 the electric pulse device of item 6, wherein the control circuit is operable to receive a second input indicative of the frequency and to cause the conversion circuit to adjust the frequency of the bipolar pulse voltage based on the received second input.

Item 10 the electric pulse device according to item 1, further comprising: a bleed-off resistor coupled between the DC power source and the conversion circuit and operable to bleed off energy in the event of an emergency stop; and scram switch means coupled to the dc power source, the bleed resistor and the conversion circuit, and operable to break the electrical connection of the dc power source to the conversion circuit in response to the scram switch being turned on; turning off the direct-current power supply; and discharging energy through a discharge resistor.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims (10)

1. An electrical pulse apparatus for treating a tumor, comprising:

a DC power supply (6);

a conversion circuit (8) coupled to the DC power source and operable to convert DC voltage from the DC power source into bipolar pulse voltage, the conversion circuit comprising a drive circuit (80), a first inverting branch comprising a first insulated gate bipolar transistor and a second insulated gate bipolar transistor in series, and a second inverting branch in parallel with the first inverting branch comprising a third insulated gate bipolar transistor and a fourth insulated gate bipolar transistor in series; and

the drive circuit is operable to apply a first pair of positive and negative drive signals alternately to the first and second insulated gate bipolar transistors and to apply a second pair of positive and negative drive signals, opposite to the first pair of positive and negative drive signals, alternately to the third and fourth insulated gate bipolar transistors, so that the conversion circuit (8) generates the bipolar pulse voltage.

2. The electric pulse device of claim 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range of 0V to +18V, and

the negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-8V.

3. The electric pulse device according to claim 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range of 0V to + 15V; and is

The negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-5V.

4. The electric pulse device according to claim 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range of 0V to + 15V; and is

The negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-8V.

5. The electric pulse device according to claim 1, wherein the positive drive signal of the first pair of positive and negative drive signals is selected from the range of 0V to + 18V; and is

The negative drive signal of the first pair of positive and negative drive signals is selected from the range from 0V to-5V.

6. The electric pulse device of claim 1, further comprising a control circuit (4) coupled to the conversion circuit and operable to receive a first input indicative of a voltage and adjust the direct current power supply based on the received first input to generate the adjusted direct current voltage.

7. The electric pulse device of claim 1, wherein the conversion circuit further comprises a voltage detection device operable to detect the direct current voltage.

8. The electric pulse device of claim 6, wherein the control circuit is operable to:

receiving the detected direct current voltage;

determining that the detected direct current voltage exceeds a threshold; and

causing the drive circuit to turn off the first, second, third, and fourth insulated-gate bipolar transistors in response to the detected direct-current voltage exceeding a threshold.

9. The electric pulse device of claim 6, wherein the control circuit is operable to receive a second input indicative of a frequency, and to cause the conversion circuit to adjust the frequency of the bipolar pulse voltage based on the received second input.

10. The electric pulse device according to claim 1, further comprising:

a bleed-off resistor coupled between the DC power supply and the conversion circuit and operable to bleed off energy in the event of an emergency stop; and

an emergency stop switching device coupled to the DC power source, the bleed off resistor, and the conversion circuit, and operable to:

in response to the scram switch being turned on, disconnecting the electrical connection of the DC power source to the converted electrical circuit;

turning off the direct current power supply; and

energy is discharged through the discharge resistor.

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