Tumor electric field treatment device and tumor electric field treatment system

Abstract

Provided is a tumor electric field treatment device including: an alternating current power supply module configured to output an alternating electric signal; an adjustable filter electrically connected to the alternating current power supply module to output a filtered alternating electric signal; and a controller configured to control a frequency of the alternating electric signal output by the alternating current power supply module, and in response to a change in the frequency of the alternating electric signal, adjust at least a cutoff frequency of the adjustable filter.

Description

Technical Field

[0001] This disclosure relates to a tumor electric field therapy device and a tumor electric field therapy system. Background Technology

[0002] Studies have shown that electric field therapy is effective in treating diseases such as glioblastoma, non-small cell lung cancer, and malignant pleural mesothelioma. The electric field applied by this treatment method can affect the aggregation of microtubules, prevent spindle formation, inhibit the process of mitosis, and induce apoptosis in cancer cells.

[0003] In tumor electric field therapy, cancer cells exhibit varying degrees of sensitivity to electric fields of different frequencies. Therefore, for specific cancer cells, a fixed-frequency electric field is often applied to intervene in their mitotic process. However, in certain situations, researchers may wish to apply electric fields of multiple frequencies to cancer cells. Current tumor electric field therapy devices possess inverter circuits that can output alternating current at different frequencies.

[0004] To reduce the impact of high-order harmonics on patients, tumor electric field therapy devices often use filters after the electric field module to suppress harmonics, such as the 3rd, 5th, and 7th harmonics of the fundamental frequency. When the electric field frequency changes from a previously set fixed frequency to another, the filter's adaptability decreases. For example, when the electric field frequency is adjusted from 150kHz to 200kHz, the harmonic frequencies will change accordingly, and the filter's ability to suppress harmonics will decrease, affecting treatment efficacy and user experience. If the tumor electric field therapy device needs to replace the corresponding filter before switching treatment frequencies to adapt to the filter, replacing the filter will interrupt the electric field, disrupt the continuity of treatment, and affect the treatment effect. Summary of the Invention

[0005] It would be beneficial to provide a mechanism to alleviate, reduce, or even eliminate one or more of the aforementioned problems.

[0006] According to one aspect of this disclosure, a tumor electric field therapy device is provided, comprising: an AC power module configured to output an alternating electrical signal; an adjustable filter electrically connected to the AC power module to output a filtered alternating electrical signal; and a controller configured to control the frequency of the alternating electrical signal output by the AC power module, and to adjust at least the cutoff frequency of the adjustable filter in response to a change in the frequency of the alternating electrical signal.

[0007] According to one embodiment of this disclosure, the tunable filter includes an all-pole filter or a non-all-pole filter.

[0008] According to one embodiment of this disclosure, the all-pole filter includes: an input port, the input port including a first input terminal and a second input terminal; an output port, the output port including a first output terminal and a second output terminal; a first capacitor and a second capacitor, the first capacitor and the second capacitor being connected in parallel between the first output terminal and the second output terminal; a first inductor and a second inductor, the first inductor and the second inductor being connected in series between the first input terminal and the first output terminal; a first switch, the first switch being connected in parallel with the second inductor; and a second switch, the second switch being connected in series with the second capacitor.

[0009] According to one embodiment of this disclosure, the non-full-pole filter includes: an input port, the input port including a first input terminal and a second input terminal; an output port, the output port including a first output terminal and a second output terminal; a first capacitor and a second capacitor, the first capacitor and the second capacitor being connected in parallel between the first output terminal and the second output terminal; a first inductor and a second inductor, the first inductor and the second inductor being connected in series between the first input terminal and the first output terminal; a third inductor and a fourth inductor, the third inductor and the fourth inductor being connected in series between the second input terminal and the second output terminal, wherein the third inductor is differentially symmetrical with the first inductor, and the fourth inductor is differentially symmetrical with the second inductor; and a third capacitor and a fourth capacitor, wherein the third capacitor is connected in parallel with the first inductor and the second inductor. The fourth capacitor is connected in parallel with the third inductor and the fourth inductor, and the third capacitor and the fourth capacitor are differentially symmetrical; a first capacitor group and a second capacitor group, wherein the first capacitor group includes a plurality of capacitors connected in parallel with each other in parallel with the first inductor and the second inductor, and the second capacitor group includes a plurality of capacitors connected in parallel with each other in parallel with the third inductor and the fourth inductor, and the plurality of capacitors in the first capacitor group and the plurality of capacitors in the second capacitor group are differentially symmetrical; and a plurality of switches, wherein the first switch of the plurality of switches is connected in series with the second capacitor, the second switch of the plurality of switches is connected in parallel with the second inductor, the third switch of the plurality of switches is connected in parallel with the fourth inductor, and the remaining switches of the plurality of switches are connected in series with the plurality of capacitors in the first capacitor group and the plurality of capacitors in the second capacitor group respectively.

[0010] According to one embodiment of this disclosure, the first capacitor bank further includes a first adjustable capacitor connected in parallel with the first inductor and the second inductor, and the second capacitor bank further includes a second adjustable capacitor connected in parallel with the third inductor and the fourth inductor, wherein the first adjustable capacitor and the second adjustable capacitor are differentially symmetrical.

[0011] According to one embodiment of this disclosure, the non-full-pole filter includes a dual-frequency non-full-pole filter and a dual-notch non-full-pole filter.

[0012] According to one embodiment of this disclosure, the dual-frequency non-full-pole filter includes: an input port, the input port including a first input terminal and a second input terminal; an output port, the output port including a first output terminal and a second output terminal; a first capacitor, the first capacitor being connected in parallel between the first output terminal and the second output terminal; a first inductor and a second inductor, the first inductor and the second inductor being connected in series between the first input terminal and the first output terminal; a second capacitor, the second capacitor being connected in parallel with the first inductor; a third capacitor, the third capacitor being connected in parallel with the second inductor; and a first switch, the first switch being connected in parallel with the third capacitor.

[0013] According to one embodiment of this disclosure, the dual notch non-full pole filter includes: an input port, the input port including a first input terminal and a second input terminal; an output port, the output port including a first output terminal and a second output terminal; a first capacitor, the first capacitor being connected in parallel between the first output terminal and the second output terminal; a first inductor, the first inductor being electrically connected between the first input terminal and the first output terminal; a second capacitor, the second capacitor being connected in parallel with the first inductor; a third capacitor, the third capacitor being connected in parallel with the second capacitor; and a first switch, the first switch being connected in series with the third capacitor.

[0014] According to one embodiment of this disclosure, it further includes a conditioning circuit electrically connected to the adjustable filter and configured to condition the filtered alternating signal for output to the electrode array.

[0015] According to one embodiment of this disclosure, the conditioning circuit includes at least one of a protection circuit, a detection circuit, or an electric field one-to-multiple output circuit.

[0016] According to one embodiment of this disclosure, the controller is coupled to the conditioning circuit and configured to control the conditioning circuit.

[0017] According to one embodiment of this disclosure, it further includes: a low-pass filter electrically connected between the AC power module and the adjustable filter, and configured to perform low-pass filtering on the alternating electrical signal output by the AC power module, and output the low-pass filtered alternating electrical signal to the adjustable filter.

[0018] According to another aspect of this disclosure, a tumor electric field therapy system is provided, comprising: a voltage generator as described above; and an electrode array configured to receive alternating electrical signals from the voltage generator to establish a corresponding electric field.

[0019] These and other aspects of this disclosure will be apparent from the embodiments described below, and will be elucidated with reference to the embodiments described below. Attached Figure Description

[0020] Further details, features, and advantages of this disclosure are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0021] Figure 1 This is a schematic block diagram of a tumor electric field therapy system according to exemplary embodiments of the present disclosure;

[0022] Figure 2 It is based on Figure 1 The diagram shows a schematic circuit of the AC power supply module of the tumor electric field therapy system.

[0023] Figure 3 This is a schematic circuit diagram of an all-pole filter according to exemplary embodiments of the present disclosure;

[0024] Figure 4 This is a schematic circuit diagram of a non-all-pole filter according to another exemplary embodiment of the present disclosure;

[0025] Figure 5 This is a schematic circuit diagram of a dual-frequency non-full-pole filter according to yet another exemplary embodiment of the present disclosure;

[0026] Figure 6 This is a schematic circuit diagram of a dual-notch non-full-pole filter according to yet another exemplary embodiment of the present disclosure;

[0027] Figure 7 This is a schematic circuit diagram of a conditioning circuit according to an exemplary embodiment of the present disclosure;

[0028] Figure 8 This is a schematic circuit diagram of a low-pass filter according to an exemplary embodiment of the present disclosure. Detailed Implementation

[0029] Exemplary embodiments of this disclosure will now be described in detail, which can be used for many reasons, such as alleviating or reducing these undesirable side effects.

[0030] Figure 1 This is a schematic block diagram of a tumor electric field therapy system according to exemplary embodiments of the present disclosure. Reference Figure 1The tumor electric field therapy system includes a voltage generator 50 and an electrode array 40. The voltage generator 50 includes an AC power module 10, an adjustable filter 60, and a controller 30. The AC power module 10 is configured to output an alternating electrical signal. The adjustable filter 60 is electrically connected to the AC power module 10 to output a filtered alternating electrical signal. The controller 30 is configured to control the frequency of the alternating electrical signal output by the AC power module 10 and, in response to changes in the frequency of the alternating electrical signal, adjust at least the cutoff frequency of the adjustable filter 60.

[0031] Figure 2 yes Figure 1 A schematic circuit diagram of the AC power module 10 is shown. In some examples, refer to... Figure 2 The AC power module 10 is configured as a full-bridge inverter topology. VCC is a programmable adjustable DC power supply used to power the AC power module 10. S30, S31, S32, and S33 are switching devices. The switching devices S30, S31, S32, and S33 are controlled to turn on and off by the controller 30 or a driver (not shown). When S30 and S33 are closed and S31 and S32 are open, the left side of the transformer L30 is at a high level and the right side is at a low level; conversely, when S30 and S33 are open and S31 and S32 are closed, the left side of the transformer L30 is at a low level and the right side is at a high level, thereby converting the DC signal into an AC signal. The transformer L30 is used to output the AC signal and is electrically connected to the input terminal of the adjustable filter 60.

[0032] Using the voltage generator 50 provided in this disclosure, when the treatment frequency of the tumor electric field therapy system is switched, the filtering characteristics of the adjustable filter 60 can be quickly changed by the program set in the tumor electric field therapy system. This maintains the low distortion rate of the output electric field waveform without interrupting the electric field to maintain the continuity of treatment, thereby maintaining a good treatment effect.

[0033] According to some embodiments, the tunable filter 60 includes an all-pole filter or a non-all-pole filter. For example, the tunable filter 60 can be an all-pole filter such as a Butterworth filter, a Chebyshev filter, or a Bessel filter, or a non-all-pole filter such as an elliptic function filter, an inverse Chebyshev filter, or a notch filter.

[0034] According to some embodiments, the tunable filter 60 is an all-pole filter, including an input port, which includes a first input terminal and a second input terminal; an output port, which includes a first output terminal and a second output terminal; a first capacitor and a second capacitor, which are connected in parallel between the first output terminal and the second output terminal; a first inductor and a second inductor, which are connected in series between the first input terminal and the first output terminal; a first switch, which is connected in parallel with the second inductor; and a second switch, which is connected in series with the second capacitor.

[0035] Figure 3 This is a schematic circuit diagram of an all-pole filter 100 according to an exemplary embodiment of the present disclosure. Figure 3 As shown, the all-pole filter 100 includes input ports (input terminals IN+ and IN-), output ports (output terminals OUT+ and OUT-), inductors L1 and L2, capacitors C1 and C2, and switches S1 and S2. Input terminals IN+ and IN- are electrically connected to the AC power supply module 10; capacitors C1 and C2 are connected in parallel between output terminals OUT+ and OUT-; inductors L1 and L2 are connected in series between input terminal IN+ and output terminal OUT+; switch S2 is connected in series with capacitor C2; switch S1 is connected in parallel with inductor L2; and output terminals OUT+ and OUT- output the filtered alternating current signal.

[0036] In some examples, the all-pole filter 100, controlled by the controller 30, can obtain the following three states through switches S1 and S2:

[0037] State 1: S1 is on, S2 is off, and the effective components of the full-pole filter 100 are L1 and C1.

[0038] State 2: With S1 and S2 disconnected, the effective components of the full-pole filter 100 are L1, L2, and C1.

[0039] State 3: S1 is open, S2 is on, and the effective components of the full-pole filter 100 are L1, L2, C1, and C2.

[0040] In some examples, for alternating signals with fundamental frequencies of 150kHz, 200kHz, and 300kHz output by the AC power module 10, L1, L2, C1, and C2 in the full-pole filter 100 can be configured as 28uH, 14uH, 5.7nF, and 2.8nF, respectively. When the controller 30 controls the alternating signal output by the AC power module 10 to be 300kHz, in response to the frequency change of the alternating signal, the controller 30 controls switches S1 and S2 to switch to state 1, adjusting the cutoff frequency of the adjustable filter 60 to approximately 400kHz, which can effectively attenuate the harmonics (900kHz, 1500kHz, etc.) corresponding to the 300kHz fundamental frequency. When the controller 30 controls the alternating signal output by the AC power module 10 to be 200kHz, in response to the frequency change of the alternating signal, the controller 30 controls switches S1 and S2 to switch to state 1, adjusting the cutoff frequency of the adjustable filter 60 to approximately 400kHz, which can effectively attenuate the harmonics (900kHz, 1500kHz, etc.) corresponding to the 300kHz fundamental frequency. In state 2, the cutoff frequency of the adjustable filter 60 is adjusted to approximately 325kHz, which can effectively attenuate the harmonics (600kHz, 1000kHz, etc.) corresponding to the 200kHz fundamental frequency. When the alternating current signal output by the AC power module 10 controlled by the controller 30 is 150kHz, in response to the frequency change of the alternating current signal, the controller 30 controls the switches S1 and S2 to switch to state 3 above, adjusting the cutoff frequency of the adjustable filter 60 to approximately 266kHz, which can effectively attenuate the harmonics (450kHz, 750kHz, etc.) corresponding to the 150kHz fundamental frequency.

[0041] In some examples, the state switching of the full-pole filter 100 is completed within 1 ms.

[0042] In some examples, the all-pole filter 100 can be controlled to switch between two or three states.

[0043] In some examples, a switch can be used to control an inductor with a smaller inductance value, thereby reducing the operating voltage of the switching device. Similarly, a switch can be used to control a capacitor with a smaller capacitance value, thereby reducing the conduction current of the switching device and saving design costs and space.

[0044] In some examples, smaller solid-state relays can be selected as switches to save on design costs and space.

[0045] In some examples, the capacitor can have a low equivalent series resistance, such as an MMKP82 capacitor.

[0046] In some examples, the inductor can be a vertical inductor with an iron-silicon-aluminum core.

[0047] In some examples, inductors L1 and L2 can be replaced by a single center-tapped inductor instead of two inductors to reduce the size of the tunable filter 60.

[0048] In some examples, when the alternating current signal received at the input terminals IN+ and IN- of the full-pole filter 100 has undergone preprocessing (e.g., filtering by the low-pass filter 70) and the low-frequency harmonic components are significantly attenuated, the -3dB point frequency of the full-pole filter 100 can be increased, reducing the size and cost of the adjustable filter 60. For example, when the 3rd and 5th harmonic components of the alternating current signal are small, the -3dB point of the full-pole filter 100 can be shifted to after the 5th harmonic.

[0049] In some examples, capacitors, inductors, and switches can be added accordingly to enable the all-pole filter 100 to obtain more filter states or to form a 3rd, 4th, or higher order filter to obtain better frequency selection characteristics.

[0050] In some examples, the calculated result can be approximated by combining multiple devices (capacitors, inductors, and switches) in parallel or series, so that the capacitance or inductance value of the actual device is as close as possible to or the same as the calculated result.

[0051] According to some embodiments, the adjustable filter 60 is a non-all-pole filter, including an input port comprising a first input terminal and a second input terminal; an output port comprising a first output terminal and a second output terminal; a first capacitor and a second capacitor connected in parallel between the first and second output terminals; a first inductor and a second inductor connected in series between the first input terminal and the first output terminal; a third inductor and a fourth inductor connected in series between the second input terminal and the second output terminal, wherein the third inductor is differentially symmetrical with the first inductor, and the fourth inductor is differentially symmetrical with the second inductor; and a third capacitor and a fourth capacitor, wherein the third capacitor is connected in parallel with the first and second inductors. The fourth capacitor is connected in parallel with the third and fourth inductors, and the third and fourth capacitors are differentially symmetrical; a first capacitor group and a second capacitor group, wherein the first capacitor group includes multiple capacitors connected in parallel with the first and second inductors, and the second capacitor group includes multiple capacitors connected in parallel with the third and fourth inductors, and the multiple capacitors of the first capacitor group and the multiple capacitors of the second capacitor group are differentially symmetrical; and a plurality of switches, wherein the first switch of the plurality of switches is connected in series with the second capacitor, the second switch of the plurality of switches is connected in parallel with the second inductor, the third switch of the plurality of switches is connected in parallel with the fourth inductor, and the remaining switches of the plurality of switches are connected in series with the multiple capacitors of the first capacitor group and the multiple capacitors of the second capacitor group respectively.

[0052] Figure 4 This is a schematic circuit diagram of a non-all-pole filter 200 according to another exemplary embodiment of this disclosure. Figure 4As shown, the non-full-pole filter 200 includes input ports (input terminals IN+ and IN-), output ports (output terminals OUT+ and OUT-), inductors L3+, L3-, L4+, L4-, capacitors C7, C8, C3+, C3-, a capacitor bank including capacitors C4+ to Cn+, a capacitor bank including capacitors C4- to Cn+, and multiple switches (S3+ to Sn+ and S3- to Sn-). The input terminals IN+ and IN- are electrically connected to the AC power module 10; capacitors C7 and C8 are connected in parallel between the output terminals OUT+ and OUT-; inductors L3+ and L4+ are connected in series between the input terminal IN+ and the output terminal OUT+, and inductors L3- and L4- are connected in series between the input terminal IN- and the output terminal OUT-. Inductors L3+ and L3- are differentially symmetrical, and inductors L4+ and L4- are differentially symmetrical; capacitor C3+ is connected in parallel with inductors L3+ and L4+, and capacitor C3- is connected in parallel with inductors L3- and L4-, and capacitors C3+ and C3- are differentially symmetrical; including capacitors C4+ to C4+... The capacitor bank Cn+ is connected in parallel with inductors L3+ and L4+, and capacitors C4+ to Cn+ are connected in parallel with each other; the capacitor bank including capacitors C4- to Cn- is connected in parallel with inductors L3- and L4-, and capacitors C4- to Cn- are connected in parallel with each other; capacitors C4+ to Cn+ and C3- to Cn- are differentially symmetrical; switch S6 is connected in series with capacitor C8; switch S3+ is connected in parallel with inductor L4+; switch S3- is connected in parallel with inductor L4-; the remaining switches are connected in series with capacitors C4+ to Cn+ and C4- to Cn- respectively; the output terminals OUT+ and OUT- output filtered alternating electrical signals.

[0053] According to some embodiments, the first capacitor bank in the non-full-pole filter further includes a first adjustable capacitor connected in parallel with the first inductor and the second inductor, and the second capacitor bank further includes a second adjustable capacitor connected in parallel with the third inductor and the fourth inductor, wherein the first adjustable capacitor and the second adjustable capacitor are differentially symmetrical.

[0054] like Figure 4 As shown, the first capacitor bank in the non-full-pole filter 200 also includes an adjustable capacitor C6+ connected in parallel with inductors L3+ and L4+, and the second capacitor bank also includes an adjustable capacitor C6- connected in parallel with inductors L3- and L4-.

[0055] In some examples, the adjustable capacitor C6+ can be connected to the circuit to fine-tune the circuit's harmonic suppression capability. For instance, when the output terminals OUT+ and OUT- of the non-full-pole filter 200 are connected to a harmonic detection module, a closed loop can be formed by adjusting the capacitance value of C6+ and harmonic detection. C6+ is configured with appropriate parameters to minimize the additional harmonic components caused by filter device errors and load deviations, achieving real-time adjustable low-distortion AC output. It is worth noting that the capacitance value of the adjustable capacitor is generally between 10pF and 200pF, and the voltage rating is generally within 100Vpp.

[0056] In some examples, the differentially symmetrical devices have the same specifications, such as L3+ and L3-, thus forming a differential filter. Simultaneously, the differentially symmetrical switches can share the same control circuit; that is, the controller 30 can simultaneously control the differentially symmetrical switches, such as simultaneously controlling the conduction and disconnection of S3+ and S3-, or simultaneously controlling the conduction and disconnection of S4+ and S4-, achieving synchronous control and reducing circuit complexity. For example, the input pins of S3+ and S3- can be short-circuited through conductive traces. There can be multiple circuits consisting of capacitors and switches between C5+ and Cn+, and between C5- and Cn-. In the non-full-pole filter 200, L3+, L3-, L4+, L4-, S3+, S3-, C7, C8, and S6 constitute the basic filter components, and the inductance value is half that of a single-ended filter to form a differential filter. C3+ to Cn+ are all devices that form a zero. By controlling the on and off states of the corresponding switches S4+ to Sn+, the capacitors connected in series with them are connected to the filter, thus forming a zero at a specific frequency. The basic logic for the values ​​of C3+ to Cn+ is as follows:

[0057]

[0058] Where C is the required equivalent capacitance value under a certain state, f is the frequency at which significant attenuation is expected (hereinafter referred to as the notch point frequency), and L is the equivalent inductance value connected in parallel with C under the same state. For example, L3+ is configured as 5uH, L4+ is configured as 3uH, and when S3+ is off, the equivalent inductance value of L is 8uH. If significant attenuation is desired at 500kHz, then C is approximately 12.67nF, meaning the equivalent capacitance value of the circuits related to C3+ to Cn+ reaches 12.67nF. The value logic for C3- to Cn- is consistent with the value logic for C3+ to Cn+ described above.

[0059] In some examples, the non-full-pole filter 200 has multiple states, the number of which depends on the number of lines between C5+ and Cn+, and between C5- and Cn-. However, the filter has three basic states:

[0060] State 1: S3+ and S3- are on, S6 is off. The effective components in the basic elements of the non-full pole filter 200 are L3+, L3- and C7.

[0061] State 2: With S3+ and S3- disconnected, and S6 disconnected, the effective components in the basic elements of the non-full-pole filter 200 are L3+, L3-, L4+, L4-, and C7.

[0062] State 3: S3+ and S3- are disconnected, and S6 is turned on. The effective components in the basic elements of the non-full pole filter 200 are L3+, L3-, L4+, L4-, C7, and C8.

[0063] In some examples, for alternating signals with fundamental frequencies of 150kHz, 200kHz, and 300kHz output by AC power module 10, the basic components L3+, L3-, L4+, L4-, C7, and C8 in the non-full-pole filter 200 can be configured as 14uH, 14uH, 7uH, 7uH, 5.7nF, and 2.8nF, respectively. When the controller 30 controls the alternating signal output by AC power module 10 to be 300kHz, in response to the frequency change of the alternating signal, the controller 30 controls switches S3+, S3-, and S6 to switch to state 1 above, adjusting the cutoff frequency of the adjustable filter 60 to approximately 400kHz, which can effectively attenuate the harmonics (900kHz, 1500kHz, etc.) corresponding to the 300kHz fundamental frequency; when the controller 30 controls the alternating signal output by AC power module 10 to be 200kHz, in response to the frequency change of the alternating signal, the controller 30 controls switches S3+, S3-, and S6 to switch to state 1 above, adjusting the cutoff frequency of the adjustable filter 60 to approximately 400kHz, which can effectively attenuate the harmonics (900kHz, 1500kHz, etc.) corresponding to the 300kHz fundamental frequency. In state 2, adjusting the cutoff frequency of the adjustable filter 60 to approximately 325kHz can effectively attenuate the harmonics (600kHz, 1000kHz, etc.) corresponding to the 200kHz fundamental frequency. When the controller 30 controls the alternating signal output by the AC power module 10 to be 150kHz, in response to the frequency change of the alternating signal, the controller 30 controls switches S3+, S3-, and S6 to switch to state 3, adjusting the cutoff frequency of the adjustable filter 60 to approximately 266kHz, which can effectively attenuate the harmonics (450kHz, 750kHz, etc.) corresponding to the 150kHz fundamental frequency.

[0064] Furthermore, for the third harmonics output by the AC power module 10 with fundamental frequencies of 150kHz, 200kHz, and 300kHz, according to the above formula (1), C3+ and C3- can be configured as 2.23nF, C4+ and C4- can be configured as 1.12nF, C5+ and C5- can be configured as 2.6nF, C7+ to Cn+ can be configured as no device, C7- to Cn- can be configured as no device, and C6+ and C6- are configured as not connected to the circuit. When the alternating current signal output by the AC power module 10 controlled by the controller 30 is 300kHz, in response to the frequency change of the alternating current signal, the controller 30 controls switches S3+, S3-, and S6 to switch to state 1 above, and opens switches S4+, S4-, S5+, and S5-, so that the equivalent capacitance in parallel with the inductor is 2.23nF, and adjusts the notch point frequency of the adjustable filter 60 to about 900kHz, which can effectively attenuate the third harmonic (900kHz) corresponding to the 300kHz fundamental frequency; when the controller... When the alternating current signal output by the AC power module 10 controlled by the controller 30 is 200kHz, in response to the frequency change of the alternating current signal, the controller 30 controls switches S3+, S3-, and S6 to switch to state 2 above, and turns on switches S4+ and S4-, and turns off switches S5+ and S5-, so that the equivalent capacitance in parallel with the inductor is 3.35nF. The notch point frequency of the adjustable filter 60 is adjusted to about 600kHz, which can effectively attenuate the third harmonic (600kHz) corresponding to the 200kHz fundamental frequency. When the alternating current signal output by the AC power module 10 controlled by the controller 30 is 150kHz, in response to the frequency change of the alternating current signal, the controller 30 controls the switches S3+, S3- and S6 to switch to the above state 3, and turns on the switches S4+, S4-, S5+ and S5-, so that the equivalent capacitance in parallel with the inductor is 5.95nF, and adjusts the notch point frequency of the adjustable filter 60 to about 450kHz, which can effectively attenuate the third harmonic (450kHz) corresponding to the 150kHz fundamental wave.

[0065] In some examples, capacitors, inductors, and switches can be added accordingly to fine-tune the cutoff frequency of the non-full-pole filter 200. For instance, if the fundamental frequency of the alternating signal is 145kHz, which is close to the fundamental frequency of the alternating signal (150kHz) when the controller 30 switches S3+, S3-, and S6 are switched to state 3, a set of capacitors and switches can be added between C5+ and Cn+ and between C5- and Cn-. If the capacitor is 0.42nF, then when the switch is turned on, the total equivalent capacitance is 6.37nF, and the cutoff frequency of the non-full-pole filter 200 is approximately 435kHz. It is worth noting that the addition or removal of capacitors, inductors, and switches in the non-full-pole filter 200 is not limited to this. Figure 3 The device combination shown.

[0066] In some examples, the effect of switches with large equivalent output capacitance can be eliminated by adjusting the capacitor values. For instance, if the switch's equivalent output capacitance is approximately 200pF, and it needs to be equivalent to a 200pF capacitor when the switch is open, then for the three fundamental frequencies of 150kHz, 200kHz, and 300kHz, C3+ and C3- can be adjusted to 1.87nF, C4+ and C4- to 1.293nF, and C5+ and C5- to 2.787nF. When the switch is open, the equivalent capacitances of C4+ and S4+ are 0.173nF, C4- and S4- are 0.173nF, C5+ and S5+ are 0.187nF, and C5- and S5- are 0.187nF. In state 1, controller 30 disconnects switches S4+, S4-, S5+, and S5-, and the equivalent capacitance in parallel with the inductor is (1.87 + 0.173 + 0.187) nF, or 2.23 nF. Similarly, in state 2, controller 30 turns on switches S4+ and S4- and disconnects switches S5+ and S5-, and the equivalent capacitance in parallel with the inductor is (1.87 + 1.293 + 0.187) nF, or 3.35 nF. In state 3, controller 30 turns on switches S4+, S4-, S5+, and S5-, and the equivalent capacitance in parallel with the inductor is (1.87 + 1.293 + 2.787) nF, or 5.95 nF. This method of adjusting the capacitance is also applicable to other embodiments.

[0067] According to some embodiments, the non-full-pole filter includes a dual-frequency non-full-pole filter and a dual-notch non-full-pole filter. For example, when the alternating signal output by the controller 30 from the AC power module 10 has only two different frequencies, the adjustable filter 60 can be a dual-frequency non-full-pole filter or a dual-notch non-full-pole filter.

[0068] According to some embodiments, a dual-frequency non-full-pole filter includes an input port, which includes a first input terminal and a second input terminal; an output port, which includes a first output terminal and a second output terminal; a first capacitor connected in parallel between the first output terminal and the second output terminal; a first inductor and a second inductor connected in series between the first input terminal and the first output terminal; a second capacitor connected in parallel with the first inductor; a third capacitor connected in parallel with the second inductor; and a first switch connected in parallel with the third capacitor.

[0069] Figure 5 This is a schematic circuit diagram of a dual-frequency non-full-pole filter 300 according to yet another exemplary embodiment of this disclosure. Figure 5As shown, the dual-frequency non-full-pole filter 300 includes input ports (input terminals IN+ and IN-), output ports (output terminals OUT+ and OUT-), inductors L10 and L11, capacitors C10, C11, and C12, and switch S11. Input terminals IN+ and IN- are electrically connected to the AC power module 10; output terminals OUT+ and OUT- output the filtered alternating current signal; capacitor C12 is connected in parallel between output terminals OUT+ and OUT-; inductors L10 and L11 are connected in series between input terminal IN+ and output terminal OUT+; capacitor C10 is connected in parallel with inductor L10; capacitor C11 is connected in parallel with inductor L11; and switch S11 is connected in parallel with capacitor C11.

[0070] In some examples, for alternating signals output by AC power module 10 with only two fundamental frequencies and a frequency ratio close to an odd ratio (e.g., f1:f2 = 3:5, 5:7, or 3:7, etc.), the dual-frequency non-full-pole filter 300 can have two states:

[0071] State 1, S11 is turned on, the effective devices in the dual-frequency non-full pole filter 300 are L10, C10 and C12;

[0072] State 2, S11 is disconnected, and the effective devices in the dual-frequency non-full pole filter 300 are L10, L11, C10, C11 and C12.

[0073] In some examples, for alternating signals with fundamental frequencies of 150kHz and 250kHz and a frequency ratio of 3:5 output by AC power module 10, L10, L11, C10, C11 and C12 in dual-frequency non-full-pole filter 300 can be configured as 25uH, 17uH, 1.8nF, 7.36nF and 8.5nF respectively. When the alternating signal output by the AC power module 10 controlled by the controller 30 is 250kHz, in response to the frequency change of the alternating signal, the controller 30 controls the switch S11 to switch to state 1 above to adjust the cutoff frequency of the adjustable filter 60 to about 345kHz and the notch frequency to 750kHz, which can effectively attenuate the third harmonic (750kHz) corresponding to the 250kHz fundamental wave; when the alternating signal output by the AC power module 10 controlled by the controller 30 is 150kHz, in response to the frequency change of the alternating signal, the controller 30 controls the switch S11 to switch to state 2 above to adjust the cutoff frequency of the adjustable filter 60 to about 266kHz and the notch frequencies to 450kHz and 750kHz, which can effectively attenuate the third harmonic (450kHz) and fifth harmonic (750kHz) corresponding to the 150kHz fundamental wave.

[0074] In some examples, for the frequency ratio f1:f2 of the two fundamental frequencies output by AC power module 10 is 5:7, the input AC power can be pre-processed (e.g., filtered by low-pass filter 70) to attenuate the 3rd harmonic, and then the method in the above example can be applied to attenuate the 5th and 7th harmonics.

[0075] According to some embodiments, a dual-notch non-full-pole filter includes an input port, which includes a first input terminal and a second input terminal; an output port, which includes a first output terminal and a second output terminal; a first capacitor connected in parallel between the first output terminal and the second output terminal; a first inductor electrically connected between the first input terminal and the first output terminal; a second capacitor connected in parallel with the first inductor; a third capacitor connected in parallel with the second capacitor; and a first switch connected in series with the third capacitor.

[0076] Figure 6 This is a schematic circuit diagram of a dual-notch non-all-pole filter 400 according to yet another exemplary embodiment of the present disclosure. Figure 6 As shown, the dual-frequency non-full-pole filter 400 includes input ports (input terminals IN+ and IN-), output ports (output terminals OUT+ and OUT-), inductor L20, capacitors C20, C21, and C22, and switch S21. Input terminals IN+ and IN- are electrically connected to the AC power module 10; output terminals OUT+ and OUT- output the filtered alternating current signal; capacitor C22 is connected in parallel between output terminals OUT+ and OUT-; inductor L20 is electrically connected between input terminal IN+ and output terminal OUT+; capacitor C20 is connected in parallel with inductor L20; capacitor C21 is connected in parallel with capacitor C20; and switch S21 is connected in series with capacitor C21.

[0077] In some examples, for alternating signals output by AC power module 10 with two fundamental frequencies that are close in frequency (e.g., 240kHz and 260kHz), the dual-notch non-full-pole filter 400 can have two states:

[0078] State 1, S21 is on, the effective devices in the dual notch non-full pole filter 400 are L20, C20, C21 and C22;

[0079] State 2, S21 is disconnected, and the effective devices in the double notch non-full pole filter 400 are L20, C20 and C22.

[0080] In some examples, for the fundamental frequencies output by the AC power module 10, which are 240kHz and 260kHz, L20, C20, C21 and C22 in the dual notch non-full pole filter 400 can be configured as 25uH, 1.665nF, 0.289nF and 8.5nF, respectively. When the alternating signal output by the AC power module 10 controlled by the controller 30 is 260kHz, in response to the frequency change of the alternating signal, the controller 30 controls the switch S21 to switch to state 1 above to adjust the cutoff frequency of the adjustable filter 60 to about 345kHz and the notch frequency to 780kHz, which can effectively attenuate the third harmonic (780kHz) corresponding to the 260kHz fundamental wave; when the alternating signal output by the AC power module 10 controlled by the controller 30 is 240kHz, in response to the frequency change of the alternating signal, the controller 30 controls the switch S21 to switch to state 2 above to adjust the cutoff frequency of the adjustable filter 60 to about 345kHz and the notch frequency to 720kHz, which can effectively attenuate the third harmonic (720kHz) corresponding to the 240kHz fundamental wave.

[0081] Similar to the embodiments described above, in some examples, the influence of switches with large equivalent output capacitance can be eliminated by adjusting the capacitance value of the dual notch filter 400. For example, if the equivalent output capacitance of switch S21 is large, such as 200pF, C20 and C21 can be adjusted appropriately; C20 can be adjusted to 1.53nF, and C21 can be adjusted to 0.424nF. In state 1, the equivalent capacitance in parallel with the inductor is 1.665nF, and the notch frequency of the dual notch filter 400 is 760kHz; in state 2, the equivalent capacitance in parallel with the inductor is 1.954nF, and the notch frequency of the dual notch filter 400 is 720kHz.

[0082] According to some embodiments, the voltage generator 50 also includes a conditioning circuit 20 electrically connected to the adjustable filter 60 and configured to condition the filtered alternating electrical signal for output to the electrode array 40. Figure 1 As shown, the voltage generator 50 also includes a conditioning circuit 20 electrically connected to the adjustable filter 60 and configured to condition the filtered alternating electrical signal for output to the electrode array 40. In some examples, the conditioning circuit 20 includes functional circuitry to make the output of the adjustable filter 60 more suitable for the tumor electric field of the subject.

[0083] According to some embodiments, the conditioning circuit 20 includes at least one of a protection circuit, a detection circuit, or a one-to-many electric field output circuit. For example, the conditioning circuit 20 may be a protection circuit, a detection circuit, or a one-to-many electric field output circuit, or it may be a combination of a protection circuit and a detection circuit, or a combination of a detection circuit and a one-to-many electric field output circuit, etc.

[0084] Figure 7 This is a schematic circuit diagram of a conditioning circuit 20 according to an exemplary embodiment of the present disclosure. Figure 7 As shown, the conditioning circuit 20 includes a protection circuit and a detection circuit. L40 is a current transformer, connected in series in the circuit for isolation and current detection. Connecting a current detection module 21 to the secondary side of L40 enables isolated current monitoring. L41 is a transformer, connected in parallel in the circuit for isolation and voltage detection. Connecting a voltage detection module 22 to the secondary side of L41 enables isolated voltage monitoring. The current detection module 21 and voltage detection module 22 can use a peak detection circuit composed of operational amplifiers, followed by an analog-to-digital converter to provide this information to the controller 30. This method is commonly used in the field and will not be elaborated further. D1 and F1 combine to form a hardware protection circuit. D1 can be configured as a bidirectional TVS to protect against external electrical pulse interference. F1 is a fuse used to disconnect the circuit in the event of a short circuit fault, protecting the load.

[0085] According to some embodiments, controller 30 is coupled to conditioning circuit 20 and configured to control conditioning circuit 20. For example... Figure 1 As shown, controller 30 is coupled to conditioning circuit 20 and configured to control conditioning circuit 20.

[0086] According to some embodiments, the voltage generator 50 further includes a low-pass filter electrically connected between the AC power module 10 and the adjustable filter 60, and configured to perform low-pass filtering on the alternating signal output from the AC power module 10, and output the low-pass filtered alternating signal to the adjustable filter 60. Figure 1 As shown, the low-pass filter 70 is electrically connected between the AC power module 10 and the adjustable filter 60, and is configured to perform low-pass filtering on the alternating signal output by the AC power module 10, and output the low-pass filtered alternating signal to the adjustable filter 60.

[0087] Figure 8 This is a schematic circuit diagram of a low-pass filter 70 according to an exemplary embodiment of the present disclosure. Figure 8 As shown, the low-pass filter 70 is a second-order differential low-pass filter, including input terminal IN, output terminal OUT, capacitor C23, inductor L21 and inductor L22.

[0088] In some examples, the low-pass filter 70 can be a low-pass filter with an inductor at its input IN. Using a low-pass filter with an inductor at its input IN achieves two effects: 1. Compared to a single programmable filter, adding a low-pass filter in the pre-stage increases the filter's frequency selectivity, resulting in lower sinusoidal distortion in the output stage. 2. In a filter with an inductor at its input, the capacitor experiences less high-order harmonic energy, and the heat generated by the equivalent series resistance esr is less, resulting in higher efficiency.

[0089] According to another aspect of this disclosure, a tumor electric field therapy system is provided, including the voltage generator 50 described above; and an electrode array 40 configured to receive alternating electrical signals from the voltage generator 50 to establish a corresponding electric field.

[0090] Although this disclosure has been described and illustrated in detail in the accompanying drawings and the foregoing description, such description and illustration should be considered illustrative and suggestive, not restrictive; this disclosure is not limited to the disclosed embodiments. By studying the drawings, the disclosure, and the appended claims, those skilled in the art will be able to understand and implement variations of the disclosed embodiments in practice with respect to the claimed subject matter. In the claims, the word "comprising" does not exclude other elements or steps not listed, the indefinite article "a" or "an" does not exclude a plurality, the term "a plurality" means two or more, and the term "based on" should be interpreted as "at least partially based on". The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be beneficial.

Claims

1. A tumor electric field therapy device, comprising: The AC power module is configured to output alternating electrical signals; An adjustable filter, electrically connected to the AC power module, outputs a filtered alternating signal; as well as A controller configured to control the frequency of the alternating electrical signal output by the AC power module, and in response to frequency changes of the alternating electrical signal, to adjust at least the cutoff frequency of the adjustable filter by controlling the on / off states of one or more switches in the adjustable filter, wherein the adjustable filter includes a non-all-pole filter, the non-all-pole filter comprising: An input port, wherein the input port includes a first input terminal and a second input terminal; The output port includes a first output terminal and a second output terminal. A first capacitor and a second capacitor are connected in parallel between the first output terminal and the second output terminal. A first inductor and a second inductor are connected in series between the first input terminal and the first output terminal; A third inductor and a fourth inductor are connected in series between the second input terminal and the second output terminal, wherein the third inductor is differentially symmetrical with the first inductor and the fourth inductor is differentially symmetrical with the second inductor; A third capacitor and a fourth capacitor, wherein the third capacitor is connected in parallel with the first inductor and the second inductor, and the fourth capacitor is connected in parallel with the third inductor and the fourth inductor, and the third capacitor and the fourth capacitor are differentially symmetrical; A first capacitor bank and a second capacitor bank, wherein the first capacitor bank includes a plurality of capacitors connected in parallel with each other and in parallel with the first inductor and the second inductor, and the second capacitor bank includes a plurality of capacitors connected in parallel with each other and in parallel with the third inductor and the fourth inductor, and the plurality of capacitors in the first capacitor bank and the plurality of capacitors in the second capacitor bank are differentially symmetrical; and Multiple switches are provided, wherein a first switch is connected in series with a second capacitor, a second switch is connected in parallel with a second inductor, a third switch is connected in parallel with a fourth inductor, and the remaining switches are connected in series with corresponding capacitors in the first capacitor group and the second capacitor group.

2. The tumor electric field therapy device as described in claim 1, wherein, The first capacitor bank further includes a first adjustable capacitor connected in parallel with the first inductor and the second inductor, and the second capacitor bank further includes a second adjustable capacitor connected in parallel with the third inductor and the fourth inductor. The first adjustable capacitor and the second adjustable capacitor are differentially symmetrical.

3. The tumor electric field therapy device as described in any one of claims 1 to 2, further comprising: A conditioning circuit electrically connected to the adjustable filter and configured to condition the filtered alternating signal for output to the electrode array.

4. The tumor electric field therapy device as described in claim 3, wherein, The conditioning circuit includes at least one of the following: a protection circuit, a detection circuit, or an electric field one-to-multiple output circuit.

5. The tumor electric field therapy device as described in claim 3, wherein, The controller is coupled to the conditioning circuit and configured to control the conditioning circuit.

6. The tumor electric field therapy device as described in any one of claims 1 to 2, further comprising: A low-pass filter is electrically connected between the AC power module and the adjustable filter, and is configured to perform low-pass filtering on the alternating electrical signal output by the AC power module, and output the low-pass filtered alternating electrical signal to the adjustable filter.

7. A tumor electric field therapy system, comprising: The tumor electric field therapy device as described in any one of claims 1 to 6; as well as An electrode array is configured to receive the alternating electrical signal from the tumor electric field therapy device to establish a corresponding electric field.

Images