High-frequency generator, control unit, method for operating a high-frequency generator

Abstract

The present invention relates to a radio frequency generator (10) for connecting an electrosurgical instrument (205), the radio frequency generator (10) having an electrical output terminal (125) for the electrosurgical instrument (205), a power source (110) at least indirectly connected to the output terminal (125), and a power control device (300) for controlling a delivered power (P) delivered via the output terminal (125). In accordance with the present invention, the radio frequency generator (10) is configured to initiate delivery of the delivered power (P) when a delivered energy balancing amount (E) is greater than a delivered energy limit value (E) and to terminate delivery of the delivered power (P) when the delivered energy balancing amount (E) is below a minimum value (E) , wherein the delivered energy balancing amount (E) is determined from a supplied generator set power (P) and the delivered delivered power (P) over a sliding determination period (T) .

Description

Technical Field

[0001] The present invention relates to a high-frequency generator for connecting an electrosurgical instrument, which has an electrical output terminal for an electrosurgical instrument, a power supply connected to the output terminal at least indirectly, and a power control device for controlling the transmitted power transmitted through the output terminal.

[0002] High-frequency generators, especially high-frequency generators for powering electrosurgical instruments, are generally known. To generate resection plasma for resecing body tissue, generally, a high arcing power several times higher than the allowable average power of the generator is required. For this reason, it is significant to pulse the transmitted power of the generator, that is, transmit it as a plurality of pulses. With an appropriate length of pause between the pulses, it is possible to ensure that the allowable average power of the generator is not exceeded despite the high arcing power.

[0003] WO 2010 / 108523 describes a high-frequency generator for connecting an electrosurgical instrument that reseces body tissue by an arc. The instrument has a power control device for controlling the power transmitted through the output terminal. The power control device first causes a high output power to be transmitted in a phase for incision assistance having a set maximum period, and subsequently, if an arc ignition occurs during the phase for incision assistance, in the set period of the resection phase, causes a power lower than the above high power to be transmitted, and further subsequently, in the set period of a long pause interval, does not transmit power or causes a lower power to be transmitted where no arc occurs, or if no arc ignition has occurred until the set maximum period during incision assistance is reached, in the set period of a short pause interval, does not transmit power or causes a low power to be transmitted.

[0004] The problem underlying the present invention is to provide an improved high-frequency generator that can perform as homogeneous and good power control as possible under various ambient conditions.

[0005] For this purpose, according to the present invention, a high-frequency generator according to claim 1 is proposed.

[0006] The high-frequency generator is configured to connect an electrosurgical instrument and has an electrical output terminal for the electrosurgical instrument, a power supply connected to the output terminal at least indirectly, and a power control device for controlling the transmitted power transmitted via the output terminal.

[0007] The power control device is configured to start transmitting the transmitted power when the transmitted energy balancing amount is greater than the transmitted energy limit value, where the transmitted energy balancing amount is determined from the supplied generator set power and the transmitted power over a sliding determination period.

[0008] The present invention is based on the consideration that the determination of appropriate transmitted power can be further improved (especially with respect to the above-described approach of the prior art). According to the concept of "determination" of the transmitted energy balancing amount, it is intended to form a value that reflects the true balance between the generator set power and the transmitted power as precisely as possible, at least precisely enough for control. Here, the concept of "generator set power" represents the power that can be set by the user, transmitted from the generator via the electrode, and averaged over a determination period.

[0009] The first aspect relates to the determination of an appropriate pulse period and the pause period therebetween. In particular, in the approach where the pulse period and / or the pause period are set as fixed time windows as mentioned at the beginning, there may be a case where, even if plasma is effectively generated, the transmission of the energy pulse ends after the pulse period has elapsed.

[0010] Also, in approaches known from the prior art, in order to ensure that the maximum allowable amount of energy defined legally and / or by regulations is not exceeded during the equilibration period, there is a tendency for the fixed pause period to be selected overly long, or for the pauses to occur more frequently than necessary, which can result in a situation where potentially available energy reserves are not utilized.

[0011] The present invention includes the recognition that existing energy reserves can be better utilized by controlling the delivered power in a flexible manner, particularly adapted to the ambient conditions, without exceeding the maximum allowable generator power. In particular, impulses having an ignition power for igniting the plasma can be controlled to last longer, as long as the amount of energy obtained from the maximum allowable generator power is not exceeded, which is particularly advantageous compared to a fixed pulse duration.

[0012] Another aspect relates to better controllability of the delivered energy. Purely temporal control of the delivered energy creates a risk that the switching between the ignition power and the cut-off power is repeated in an uncontrolled manner (as disclosed in the prior art mentioned at the beginning), which can occur particularly under unstable cut-off plasma or under an overly low generator set power. In such cases, repeated delivery of a high ignition power can result in an uncontrolled high energy input to the tissue.

[0013] Based on the delivered energy equilibration amount, within the scope of the virtual energy accumulator, considering that the virtual energy accumulator has become empty due to the true amount of energy delivered, it is possible to detect how much energy has already been consumed during the latest sliding decision period, and thus, under a defined decision amount, how much energy is immediately further available. Thus, advantageously, the risk of an uncontrolled high energy input to the tissue to be treated can be reduced, or even minimized, without setting a fixed time limit for the energy delivery.

[0014] In this context, a "sliding type" means that although the determination period as the balancing frame has a fixed period, it is moved over consecutive time periods, thereby generating a time window that rotates. In this time window, the transmitted energy balancing amount is recursively recalculated, for example, for each new program cycle or for each defined cycle period. During the calculation, in particular, the generator set power and the transmitted power (truly transmitted) are balanced. Therefore, figuratively speaking, for a virtual energy accumulator defined by the determination period and the maximum transmitted energy balancing amount, energy is supplied according to the generator set power and withdrawn according to the transmitted power. The generator set power determines how much energy is supplied to the virtual energy accumulator while the truly transmitted power is simultaneously withdrawn from the virtual energy accumulator. The difference resulting from this is the transmitted energy balancing amount.

[0015] Preferably, it is configured such that the generator set power is adjustable. Specifically, this includes that the value of the generator set power, particularly a scalar numerical value having a unit of watt, can be set via an appropriate user interface or operating element. For example, such an operating element can be formed as a jog dial or a pointing device, and as an optional means, a display for displaying the latest set value of the generator set power can also be provided. The adjustability of the generator set power advantageously enables the adjustment of the transmission of the transmitted electrical energy and thus its adaptability to specific applications. Here, in some cases, legal and / or regulatory provisions should be considered, particularly as the upper power limit.

[0016] Preferably, the transmitted energy equalization amount is configured not to exceed the maximum transmitted energy equalization amount. Specifically, this means that the transmitted energy equalization amount is limited, and (figuratively speaking) the virtual energy accumulator has a maximum holding capacity and no more energy can be accumulated. By the maximum transmitted energy equalization amount, compliance with legal and / or regulatory requirements can be achieved, especially considering the generator set power. Such requirements are particularly related to the maximum allowable transmitted energy amount within a determined period. In particular, the scope is defined in the DIN standard EN60601-2-2, titled "Medical electrical equipment - Part 2-2: Particular requirements for the safety of high-frequency surgical equipment", which states that the maximum allowable transmitted energy amount of 400 J within a determined period of 1 second should not be exceeded. In such a development form, advantageously, the risk of exceeding the maximum energy amount can be reduced, especially to ensure the safety of the patient. In a possible development form, the maximum transmitted energy equalization amount can be further selected to be lower by a predetermined value, for example, by only 10% of the maximum transmitted energy equalization amount, thereby providing a safety margin for further reducing the risk of exceeding legal and / or regulatory requirements, for example.

[0017] In a range of a development form, the maximum delivered energy equalization amount is determined from the difference between the allowable energy amount and the delivered energy amount, and the allowable energy amount is configured to be the energy amount that is maximally allowed to be delivered during the equalization period. The settings regarding the allowable energy amount and the equalization period can be made based on legal and / or regulatory determinations. In this case, in this development form, in relation to the delivered energy equalization amount, compliance with legal and / or regulatory provisions can be achieved, and nevertheless, the maximum available delivery power can always be utilized (within the said provisions). This can be considered to be different from the prior art in which such compliance is achieved, in particular, by a pause period between defined delivered energy pulses that are particularly non-invasively configured, in particular, a pause period between ignition pulses, and thereby potentially available power is not utilized. In a preferred development form, the equalization period may be equal to the determination period.

[0018] The delivered energy limit value is adjustable. By the delivered energy limit value being adjustable, advantageously, the behavior of the power control device (and thus the switching-off behavior of the high-frequency generator) can be adjusted. With a low delivered energy limit value, after the point at which the delivered energy equalization amount has become equal to zero (i.e., the energy accumulator has become completely empty), the high-frequency generator can be put back into a state where the energy amount required for delivering the delivery power again, in particular, the ignition power, can be supplied quickly. However, a low delivered energy limit value also causes an excessive undershoot of the delivered energy equalization amount again, in particular, a drop to zero. If the delivered energy limit value is selected to be too low, it may also happen that the energy available in the accumulator becomes insufficient for plasma ignition. On the other hand, if the delivered energy limit value is selected to be larger, more delivered energy becomes available after the delivered energy limit value has been reached (in particular, in the case of longer ignition pulses). However, in this case, the pause period, i.e., the waiting time until the delivered energy limit value is reached, becomes correspondingly longer.

[0019] In a development form, the power control device is configured to have an equalization unit configured to periodically determine the transmitted energy equalization amount. Specifically, this includes the equalization unit constantly updating the virtual energy accumulator by periodic recalculation of the equalization amount. In this case, the periodic recalculation is performed within a cycle time shorter than the determination period. In a possible development form, the cycle time is shorter than the determination period by at least a factor of 100, preferably by a factor of 1000, particularly preferably by a factor of 10000. For example, when the determination period is 1 second, a value between 100 μs and 5 ms can be selected for the cycle time. The short cycle time advantageously ensures that the power control device is constantly supplied with the latest value of the transmitted energy equalization amount, so that closed-loop control of the transmitted power based on the transmitted energy equalization amount is possible with only negligible delay.

[0020] To solve the problems mentioned at the beginning, a power control device for a high-frequency generator is further proposed. Here, the high-frequency generator has an electrical output terminal for an electrosurgical instrument, a current source or voltage source connected at least indirectly to the output terminal, and a power control device. The power control device is configured to start transmitting the transmitted power when the transmitted energy equalization amount is greater than the transmitted energy limit value or has an initial value, and to end transmitting the transmitted power when the transmitted energy equalization amount falls below the minimum value. Here, the transmitted energy equalization amount is determined over a sliding determination period, and the transmitted energy equalization amount is formed as the difference between the generator set power and the transmitted power. In the power control device of the present invention, the advantages of the high-frequency generator of the present invention are advantageously utilized. In a possible development form of the power control device, the power control device can be configured to be suitable for retrofitting an existing high-frequency generator. For this purpose, the power control device can be configured as a (particularly replaceable) hardware module and / or software module.

[0021] To solve the problems mentioned at the beginning, a method for operating a high-frequency generator by means of a power control device is further proposed. The method is · A step of initializing the transmitted energy equalization amount to the initial energy; · When the transmitted energy equalization amount is greater than the transmitted energy limit value or has the initial energy, particularly by operating a foot switch, a step of selectively starting the transmission of the transmitted power; and.

[0022] In one development form of the method, when the transmitted energy equalization amount is equal to zero, the transmission of the transmitted power is configured to end.

[0023] In one development form of the method, the transmitted energy equalization amount is configured to be determined from the supplied generator set power and the transmitted transmitted power over a sliding decision period.

[0024] In the method of operating the high-frequency generator of the present invention, the advantages of the high-frequency generator are advantageously utilized.

[0025] Another advantage, feature, and detail of the present invention can be obtained from the following description of the preferred embodiments and further in accordance with the drawings.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 3C

Figure 4A

Figure 4B

[0027] FIG. 1 shows a high-frequency generator 10 having a power cable for connection to a current source provided on the input side. The high-frequency generator 10 is connected to a foot switch 240 used for the operation of the high-frequency generator 10. On the output side, two output poles (not shown in detail here), namely, a first output pole 125.1 and a second output pole 125.2 of the output terminal 125 of the high-frequency generator 10, are connected to the bipolar electrode 210 of the electrosurgical instrument 205 via current lines. Here, the electrosurgical instrument is provided with a bipolar resection electrode 210, and in the exemplary embodiment of FIG. 1, the bipolar resection electrode 210 is configured as a bipolar loop resection instrument.

[0028] FIG. 2 shows a basic circuit diagram of a preferred embodiment of the high-frequency generator 10 of the present invention having an improved incision behavior compared to the prior art. The illustrated embodiment is also suitable for surgical interventions, particularly in the field of transurethral resection (TURi), and other fields, such as endoscopic mucosal resection (EMR) and polypectomy.

[0029] The high-frequency generator 10 includes a power supply 110. The power supply 110 can be connected to an alternating current supply network at the input end 110.1, and on the output side, it is connected to the input end 120.1 of a clock-controllable high-frequency generator module 120 at the output end 110.2. The power supply 110 converts an alternating voltage into a direct voltage.

[0030] The high-frequency generator module 120 converts a DC voltage into an AC voltage having a frequency between 0.3 MHz and 2 MHz. The output terminal 120.2 of the high-frequency generator module 120 is connected to the bipolar electrode 210 of the electrosurgical instrument 205 via at least one current-blocking capacitor 122 and the two-pole electrical output terminal 125 of the high-frequency generator 10. The at least one current-blocking capacitor must block the transmission of direct current. Here, the transmission of the AC voltage at the output terminal 120.2 is clock-controlled. By "clock-controlled" is meant that the high-frequency generator module 120 can be clock-controlled by the operating circuit 322 such that a pulse train including a plurality of pulses having various pulse lengths and various pulse sequences is supplied to the output terminal 120.2. The pulse amplitude can vary with the passage of the pulse. The power transmission of the high-frequency generator module 120 is temporally controlled such that the transmission energy balancing amount EB can transmit a sequence of transmitted powers at various power levels and periods.

[0031] The electrosurgical instrument 205 generally consists of a cutting electrode 210 and a grip portion 212. In order to be able to electro-surgically excise the tissue 230 located in the vicinity of the cutting electrode 210 (partially shown here), a sodium chloride solution 232 can be added to the body tissue 230 in the surgical area, and plasma 234 can be formed by the electrode 210 in this area. This is done by transmitting a high-frequency current having a high power, particularly the arcing power PI, to the output terminal 120.2 of the high-frequency generator module 120. The bipolar cutting electrode 210 of the electrosurgical instrument is connected to the output terminal 120.2 of the high-frequency generator module 120 via the two-pole electrical output terminal 125. The high-frequency current transmitted to the bipolar cutting electrode 210 heats the sodium chloride solution 232 in the area of the bipolar cutting electrode 210, whereby the plasma 234 is arced. By means of the plasma 234, the surgeon can perform the desired excision on the tissue 230 applied to the cutting electrode 210. The surgeon can generally start and end such an excision process by operating a foot switch 240 (not shown here).

[0032] To maintain the plasma required for electro-surgical resection, relatively low power, especially the resection power PC, is sufficient. This is because the plasma has a much higher electrical resistance than physiological saline, so this is the case. The electrical resistance of the plasma can be in the region of several hundred Ω, while the electrical resistance of physiological saline can be in the region of about 25 Ω.

[0033] The high-frequency generator 10 has a power control device 300 including a balancing unit 320.

[0034] The balancing unit 320 has a power detection unit 330. The power detection unit 330 is connected to the output terminal 120.2 of the high-frequency generator module 120 so that the actually transmitted output power PO can be detected, especially measured. The output terminal of the power detection unit 330 is connected to a first integrator 332. The first integrator 332 is configured to integrate the value of the output power PO, especially the measured value, over a determination period TA, thereby obtaining the amount of output energy EO actually transmitted from the high-frequency generator module 120 within the determination period TA.

[0035] The balancing unit 320 further has a second integrator 334. The second integrator 334 is configured to integrate the value of the generator set power PAV over a determination period TA. The second integrator 334 is connected on the input side to a generator power setting module 342 by which the user can set the generator set power PAV. The second integrator 334 transmits the integration result from the output side to an adder 336, and by the adder, an initial energy ES is added to the integration of the generator set power, and a set energy amount EAV is determined. In a predetermined embodiment, alternatively, the set energy amount EAV can also be easily formed by multiplying the generator set power PAV by the determination period TA. In this case, EAV = PAV * TA applies.

[0036] The initial energy ES, which is added to the integral of the generator set power by the former 336, can be set via the initial energy setting module 344. In this case, the initial energy ES must be selected in particular so that the maximum transmitted energy equalization amount EBMAX is not exceeded.

[0037] In the difference former 338, the transmitted energy amount EO is subtracted from the set energy amount EAV, thereby forming the transmitted energy equalization amount EB. From this, the relationship according to the formula, that is

Equation

[0038] The operating circuit 322 is connected on the input side to the difference former 338 and the limit value setting module 346. The transmitted energy limit value EBX can be set via the limit value setting module 346. The transmitted energy limit value EBX defines in particular the minimum value of the increasing transmitted energy equalization amount EB from which the transmission of the transmitted power PO, in particular the ignition power PI, is carried out. That is, the ignition power is transmitted only when the energy amount is greater than the minimum energy amount defined by the transmitted energy limit value EBX in the virtual energy accumulator. Depending on the incoming parameters, that is, the transmitted energy equalization amount EB and the transmitted energy limit value EBX, the operating circuit 322 outputs a switch-on signal D. In order to transmit the switch-on signal D to the high-frequency generator module 120, the operating circuit 322 is connected on the output side to the high-frequency generator module 120 so as to be signal-transmittable. Through the switch-on signal D, the transmission of the transmitted energy PO by the high-frequency generator module 120 can be activated and blocked, that is, started and ended.

[0039] The balancing unit 320 operates with a cycle time TZ, which means that the above-described calculation for forming the transmitted energy balancing amount EB is newly performed in a new cycle T+1 after a cycle T with the cycle time TZ, using the updated input data, in particular the latest generator set power PAV and the latest transmitted power PO. That is, the values of the transmitted energy amount EO and the set energy amount EAV are updated in each cycle T. The cycle time TZ can be selected, for example, between 100 μs and 5 ms, depending in particular on the specific configuration of the balancing unit, in particular on the hardware and software used.

[0040] Also, the power control device 300 can be implemented completely or partially within a microcontroller in which the component 320 and another component as an optional means are programmed.

[0041] FIG. 3A schematically shows a diagram for determining the maximum transmitted energy balancing amount EBMAX, and thus (figuratively speaking) the size of the energy accumulator. The outer frame, shown here as a dashed line, is formed by technical and / or legal and / or regulatory provisions. Here, the frame can be in accordance with the provisions of the title "Medical electrical equipment - Part 2-2: Particular requirements for the safety of high-frequency surgical equipment" of DIN EN60601-2-2, which stipulates that the allowable energy amount EA of 400 J must not be exceeded within the balancing period TB of 1 second. In this case, the adjustable generator set power PAV, selected exemplarily as PAV = 300 W, will accordingly transmit a set energy amount EAV of 300 J (within the balancing period TB of 1 second). From the difference between the allowable energy amount EA and the set energy amount EAV, the total maximum transmitted energy amount EBMAX, which is 100 J here, is obtained.

[0042] FIG. 3B shows a state diagram of possible operations of the high-frequency generator. After the operation or initialization of the transmission energy equalization amount EB by the initial energy ES, the high-frequency generator 10 is in the operating state HFON. In the operating state HFON, the switch-on signal D has the value "on", and thus the high-frequency generator module 120 transmits the transmission power PO. When the transmission energy equalization amount EB falls below the minimum value EBMIN, for example, becomes zero (i.e., when the virtual energy accumulator is completely empty), the high-frequency generator 10 transitions to the off state HFOFF. In the off state HFOFF, the switch-on signal D has the value "off", and thus the high-frequency generator module 120 does not transmit the transmission power PO. In the off state HFOFF, the transmission energy equalization amount EB increases again, particularly by the input of the generator set power PAV. That is, the virtual energy accumulator is recharged. As soon as the transmission energy equalization amount EB exceeds the transmission energy limit value EBX, the high-frequency generator 10 transitions back to the operating state HFON. A high initial energy ES that can take a value up to the maximum transmission energy equalization amount EBMAX results in a transmission period of maximum length after operation. Generally within the scope of the present invention, it may be advantageous if the value of the initial energy ES is selected to be equal to the transmission energy limit value EBX. In this way, the first arcing attempt after initialization corresponds to the next arcing attempt made after reaching the transmission energy limit value EBX, particularly with respect to the pulse period and the subsequent standby period. Note that the initial energy ES can be configured to be introduced only once at the start of the treatment.

[0043] FIG. 3C shows a diagram of the time-dependent characteristics of the transmission power PO and the transmission energy equalization amount EB of a development form of the high-frequency generator 10 according to the concept of the present invention. At the first point in time T1, the electrical transmission energy PO takes the value of the arcing power PI, which is 2300 W here. The adjustable generator set power PAV is 300 W here, and the maximum transmission energy equalization amount EBMAX is 100 J (as shown in FIG. 3A).

[0044] The transmitted energy equalization amount EB ensures that a predetermined transmitted energy amount, i.e., the maximum transmitted energy equalization amount EBMAX, is not exceeded within the determination period TA. In this case, the transmission power PO may be higher than the average transmission power resulting from the quotient of the maximum transmitted energy equalization amount EBMAX and the determination period TA, especially during the time within the determination period TA. However, the high transmission power PO causes a state where the transmitted energy equalization amount EB is reduced more rapidly than new energy can be added according to the maximum virtual transmission power. In other words, within the range of the virtual energy accumulator, the transmitted energy equalization amount EB is discharged more rapidly than it is charged.

[0045] At time point T2, the transmitted energy equalization amount EB is equal to the minimum transmitted energy equalization amount EBMIN, that is, the virtual energy accumulator is depleted. Here, the minimum transmitted energy equalization amount EBMIN is equal to zero. Therefore, the pulse period of the ignition pulse started at time point T1 ends at time point T2. Since the generator set power PAV is 300W and the ignition power PI is 2300W, the power difference is 2000W. If the maximum transmitted energy equalization amount EBMAX is 100J (and the initial energy ES is 100J at first), it reaches at time point T2, 0.05s later, that is, 50ms later. At time point T2, the transmission of the transmission power PO is terminated by the high-frequency generator module 120, that is, the high-frequency generator 10 is switched to the off state HFOFF. Therefore, in the figure, the value PO of the ignition power PI drops stepwise to zero. From time point T2, the transmitted energy equalization amount EB increases at a speed corresponding to the generator set power PAV = 300W = 300J / s in particular. At the third time point T3, the transmitted energy equalization amount EB reaches the value of the transmitted energy limit value EBX, which is 60J here. Therefore, the third time point T3 is 0.2s = 200ms after the second time point T2, and T3 = 250ms applies. The time between time point T2 and time point T3 is a standby period during which the transmission power PO is not transmitted.

[0046] From time point T3, that is, after reaching the transmission energy limit value EBX, the high-frequency generator module 120 is driven via the switch-on module 323 so that the transmission of the transmission power PO is carried out again. Based on the low output resistance at the bipolar electrode, the transmission power PO takes a relatively high value, that is, a value at the level of the arcing power PI. At time point T4, the plasma is effectively arced, and accordingly, the output resistance of the bipolar electrode increases. Therefore, the transmission power PO jumps down to a low value, particularly to the cut-off power PC, where the cut-off power PC is several times lower than the arcing power PI. Here, the cut-off power PC is 100 W.

[0047] Based on the fact that the transmitted cut-off power PC is lower than the generator set power PAV, the transmission energy balancing amount EB increases from the fourth time point T4. Figuratively speaking, the virtual energy accumulator is charged more quickly than during discharge. As a result, the transmission energy balancing amount EB reaches its maximum value, that is, the maximum transmission energy balancing amount EBMAX, which is 100 J here, at the fifth time point T5. When the cut-off power PC is 100 W and the generator set power PAV is 300 W, the power difference of 200 W is 200 J / s.

[0048] With the electrosurgical instrument 205, the resection can continue beyond time point T5 until the resection process is interrupted by the release of the foot switch 240 or until the plasma is stopped. From this point not shown here, the procedures described here can be repeated for incision.

[0049] FIG. 4A shows, as a basic circuit diagram, a possible structure of the operating circuit 322. The operating circuit 322 here has three comparison modules 322A to 322C, a cycle memory 325, and a switch-on module 323. Here, the function of the operating circuit 322 during cycle Z is shown.

[0050] In the first comparison module 322A, it is checked whether the value of the transmitted energy equalization amount EB is greater than the minimum transmitted energy equalization amount EBMMIN, particularly whether it is greater than zero. If it is greater than zero, the first comparison signal A is output and conducted to the switch-on module 323. The comparison signal A and the comparison signals of the other comparison modules 322B and 322C can particularly have a Boolean property, and thus can exclusively take the value 0 or the value 1.

[0051] The cycle memory 325 stores the switch-on signal D output from the switch-on module 323 in the previous cycle Z - 1 and supplies it to the output side as the previous switch-on signal DV in the latest cycle Z. In the second comparison module 322B connected to the cycle memory 325, it is checked whether the previous switch-on signal DV is positive, that is, whether DV = D(Z - 1) = "on". If it is "on", the positive second comparison signal B is output and conducted to the switch-on module 323.

[0052] In the third comparison module 322C, the transmitted energy equalization amount EB is compared with the transmitted energy limit value EBX. If the transmitted energy equalization amount EB is greater than the transmitted energy limit value EBX, (figuratively speaking) the energy accumulator is filled to the determined minimum value. In this case, the positive third comparison signal C is output and conducted to the switch-on module 323.

[0053] The switch-on module 323 outputs a switch-on signal D that can take the value "on" or "off" depending on the comparison signals A, B, and C. Similarly, alternatively or additionally, the switch-on module 323 can output a Boolean form of the switch-on signal, that is, 1 corresponding to "on" and 0 corresponding to "off".

[0054] Figure 4B shows the possible switching states 323.1 to 323.5 of the switch-on module 323. In the first switching state 323.1, the first comparison signal A is negative, i.e., A = 0. From this, regardless of whether the second comparison signal B or the third comparison signal C is positive or negative, a negative switch-on signal D is generated. The negative switch-on signal D, i.e., the switching position "off", causes the transmission power PO not to be transmitted by the high-frequency generator module 120. This switching state 323.1 means that the transmission energy balancing amount EB is equal to zero at the latest point in time, (figuratively speaking) the virtual energy accumulator is empty.

[0055] In the second switching state 323.2, the first comparison signal A and the third comparison signal C are positive, and the second comparison signal B is negative, thereby generating a positive switch-on signal D, i.e., the switching position "on". This switch-on state 323.2 occurs when the transmission energy balancing amount EB in the latest cycle Z is greater than the transmission energy limit value EBX, and in the previous cycle Z - 1, the switch-on module 323 outputs a negative switch-on signal D, so the high-frequency generator module 120 did not transmit the transmission power PO in the previous cycle Z - 1.

[0056] In the third switching state 323.3, all three comparison signals A, B, and C are positive, so a positive switch-on signal D, i.e., the switching position "on", is generated. This switching state 323.3 means that the transmission energy balancing amount EB is greater than the transmission energy limit value EBX at the latest point in time, and in the previous cycle Z - 1, the switch-on module 323 output a positive switch-on signal D. The latter means that the high-frequency generator module 120 transmitted the transmission power PO in the previous cycle Z - 1.

[0057] In the fourth switching state 323.4, the first comparison signal A is positive, and the second comparison signal B and the third comparison signal C are negative, thereby generating a negative switch-on signal D, i.e., the switching position "off". This switching state 323.4 means that at the latest point in time, the transmitted energy balancing amount EB is smaller than the transmitted energy limit value EBX, and in the previous cycle Z-1, the switch-on module 323 output a negative switch-on signal D, i.e., the high-frequency generator module 120 did not transmit the transmitted power PO.

[0058] In the fifth switching state 323.5, the first comparison signal A and the second comparison signal B are positive, and the third comparison signal C is negative, thereby generating a positive switch-on signal D, i.e., the switching position "on". This switching state 323.5 means that at the latest point in time, the transmitted energy balancing amount EB has decreased and become smaller than the transmitted energy limit value EBX, and in the previous cycle Z-1, the switch-on module 323 output a positive switch-on signal D, i.e., the high-frequency generator module 120 transmitted the transmitted power PO.

[0059] In connection with each switching state, in particular, reference is made to the fourth switching state 323.4 and the fifth switching state 323.5. That is, in the two switching states 323.4, 323.5, the transmitted energy balancing amount EB is smaller than the transmitted energy limit value EBX.

[0060] In this case, in the fourth switching state 323.4, the previous switch-on signal DV, i.e., the switch-on signal D in the previous cycle Z-1, is negative, i.e., the transmitted energy PO was not transmitted by the high-frequency generator module 120.

[0061] However, here, as in the fifth switching state 323.5, if the switch-on signal D in the previous cycle Z-1 was positive, that is, if the high-frequency generator module 120 transmitted the transmission energy PO, then the high-frequency generator module 120 further transmits the transmission energy PO (based on the output of the positive switch-on signal D by the switch-on module 323 in the latest cycle Z). That is to say, simply put, (even if the transmission energy balancing amount EB is below the transmission energy limit value EBX), the activated high-frequency generator module 120 remains activated, and it is only when the transmission energy balancing amount EB falls below the minimum transmission energy balancing amount EBMIN, and particularly when it becomes equal to zero, that it is cut off. "Activated" and "cut off" here are particularly related to the transmission of the transmission electrical energy PO via the output terminal 120.2 of the high-frequency generator module 120, and are not related to whether the power supply 110 and / or the entire high-frequency generator 10 is on or off.

Explanation of Signs

[0062] 10 High-frequency generator 110 Power supply, clock-controllable power supply 110.1 Input terminal of the power supply 110.2 Output terminal of the power supply 120 High-frequency generator module 122 Current-blocking capacitor 125 Output terminal, output pole of the high-frequency generator 125.1 First output pole 125.2 Second output pole 205 Electrosurgical instrument 210 Resecting electrode, bipolar electrode of the electrosurgical instrument 212 Grip part of the electrosurgical instrument 230 Tissue 232 Sodium chloride solution, physiological saline 234 Plasma 240 Foot switch 300 Power control device 320 Balancing unit 322 Operating circuit 322A First comparison module 322B Second comparison module 322C Third comparison module 323 Switch-on module 323.1~323.5 First switching state~Fifth switching state 325 Cycle memory 330 Power detection unit 332 First integrator 334 Second integrator 336 Sum former 338 Difference former 342 Generator power setting module 344 Initial energy setting module 346 Limit value setting module 348 Multiplier 356 Point arc voltage 610 Virtual energy accumulator 630 True energy amount A,B,C First comparison signal~Third comparison signal D Switch-on signal DV Previous switch-on signal EA Allowable energy amount EAV Sent energy amount EB Sent energy balancing amount EBMAX Maximum sent energy balancing amount EBMIN Minimum sent energy balancing amount, minimum value EBX Sent energy limit value EO Sent energy amount ES Initial energy HFOFF High-frequency generator cut-off state HFON High-frequency generator operating state PAV Generator set power PC Cut-off power PI Point arc power PO Sent power, electricity T Time TA Decision period TB Balancing period TI Point arc time TZ cycle time Z cycle, calculation cycle

Claims

1. A high-frequency generator (10) for connecting an electrosurgical instrument (205), an electrical output terminal (125) for the electrosurgical instrument (205), a power supply (110) indirectly connected to the output terminal (125) at least via a high-frequency generator module (120), and a power control device (300) for controlling the transmitted power (PO) sent from the high-frequency generator module (120) via the output terminal (125). It has, The power control device (300), when the transmitted energy balancing amount (EB) is greater than the transmitted energy limit value (EBX), starts transmitting the transmitted power (PO), and when the transmitted energy balancing amount (EB) falls below the minimum value (EBMIN), ends the transmission of the transmitted power (PO). It is configured as such, The transmitted energy balancing amount (EB) is obtained by subtracting the transmitted energy amount (EO) from the set energy amount (EAV) over a sliding determination period (TA), The transmitted energy amount (EO) is obtained by integrating the transmitted power (PO) over the determination period, and is further updated at a cycle time (TZ). The set energy amount (EAV) is obtained by adding a value obtained by integrating the supplied generator set power (PAV) over the determination period to the initial energy (ES) set as the initial value of the energy amount of the high-frequency generator module (120). The transmitted energy balancing amount (EB) in the sliding determination period (TA) is recalculated at each cycle (Z) with the cycle time (TZ) using the updated values of the transmitted energy amount (EO) and the set energy amount (EAV), and is updated in a cycle (Z) having the cycle time (TZ). For each cycle, the set energy amount (EAV) is recalculated from the generator set power (PAV) present during the cycle, and further the transmitted energy balancing amount (EB) is recalculated from the transmitted power (PO) transmitted during the cycle. Here, the cycle time (TZ) is shorter than the sliding determination period (TA). A high-frequency generator (10), characterized by this.

2. The high-frequency generator (10) according to Claim 1, wherein the generator set power (PAV) is adjustable.

3. The high-frequency generator (10) according to claim 1 or 2, wherein the transmitted energy equalization amount (EB) does not exceed the maximum transmitted energy equalization amount (EBMAX).

4. The high-frequency generator (10) according to at least one of claims 1 to 3, wherein the transmitted energy limit value (EBX) is adjustable.

5. The high-frequency generator (10) according to at least one of claims 1 to 4, wherein the power control device (300) has an equalization unit (320) configured to periodically determine the transmitted energy equalization amount (EB).

6. A power control device (300) for the high-frequency generator (10) according to any one of claims 1 to 5, wherein the high-frequency generator (10) has an electrical output terminal (125) for an electrosurgical instrument (205), a current source or voltage source (110) indirectly connected to the output terminal (125) at least via a high-frequency generator module (120), and a power control device (300) for controlling the transmitted power (PO) sent from the high-frequency generator module (120) via the output terminal (125), and the power control device (300) is configured to start transmitting the transmitted power (PO) when the transmitted energy equalization amount (EB) is greater than the transmitted energy limit value (EBX) or has an initial energy (ES), and to end the transmission of the transmitted power (PO) when the transmitted energy equalization amount (EB) falls below the minimum value (EBMIN). The power control device (300) is characterized in that the transmitted energy equalization amount (EB) is determined over a sliding determination period (TA), and the transmitted energy equalization amount (EB) is obtained by subtracting the transmitted energy amount (EO) obtained by integrating the transmitted power (PO) from the set energy amount (EAV) obtained by adding the integral of the generator set power (PAv) and the initial energy (ES) set as the initial value of the energy amount of the high-frequency generator module (120). determined as a value.

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