Energy surgical equipment and active power detection method

Abstract

The invention discloses an energy surgical device and an active power detection method, and the method comprises the steps: calculating the voltage of two ends of a transmission cable according to the distributed resistance of the transmission cable, the distributed inductance of the transmission cable, the angular frequency of frequency energy and the output current; calculating the voltage of the surgical site according to the output voltage and the voltage at the two ends of the transmission cable; and according to the voltage and the output current of the surgical site, the active power of the frequency energy received by the surgical site is calculated. Therefore, in the active power calculation process, the influence of the distributed resistance and the distributed inductance of the transmission cable is fully considered, and the accuracy of active power detection is improved.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and particularly to an energy surgical device and an active power detection method. Background Art

[0002] Most of the medical devices with radio frequency energy function on the market currently do not have a power control function. Even for the devices with a power control function, the power calculation method is relatively simple. For example, the power is obtained by performing a mathematical operation on the sampled voltage and current. The calculation of impedance is also relatively simple. For example, it is only a direct mathematical division operation on the sampled voltage and current, and the calculated value is only the modulus of the impedance of the entire loop of the energy. The parasitic inductance and parasitic capacitance existing in the loop at high frequencies are not considered, especially for the devices containing syringe-like tubes, where a large parasitic capacitance will be formed between the inner and outer knife tubes. These factors result in the inaccurate calculation of the active power of the energy surgical device. Summary of the Invention

[0003] In view of the above technical problems, an embodiment of the present invention provides an energy surgical device and an active power detection method, aiming to improve the accuracy of the active power.

[0004] An embodiment provides an energy surgical device, including: a high-frequency generator, a transmission cable, an output device, a detection device, and a control device; the high-frequency generator is connected to the output device through the transmission cable;

[0005] The high-frequency generator is used to generate frequency-modulated energy;

[0006] The output device is used to output the frequency-modulated energy to the surgical site;

[0007] The detection device is used to detect the output voltage and output current of the frequency-modulated energy generated by the high-frequency generator;

[0008] The control device is used for:

[0009] Calculating the voltage across the transmission cable according to the distributed resistance of the transmission cable, the distributed inductance of the transmission cable, the angular frequency of the frequency-modulated energy, and the output current;

[0010] Calculating the voltage of the surgical site according to the output voltage and the voltage across the transmission cable;

[0011] Calculating the active power of the frequency-modulated energy received by the surgical site according to the voltage of the surgical site and the output current.

[0012] In an energy surgical device provided by an embodiment, the control device calculates the active power of the frequency - converted energy received by the surgical site according to the voltage of the surgical site and the output current, including:

[0013] The output voltage is an output voltage vector, including a first array after analog - to - digital sampling of the output voltage waveform in one period; the output current is an output current vector, including a second array after analog - to - digital sampling of the output current waveform in one period; the voltage of the surgical site is a voltage vector of the surgical site, including a third array calculated based on the first array and the second array; calculate the inner product of the voltage vector of the surgical site and the output current vector according to the third array and the second array; divide the inner product by the length of the second array to obtain the active power; or,

[0014] Calculate the phase difference between the voltage of the surgical site and the output current, the effective value of the voltage of the surgical site, and the effective value of the output current through fast Fourier transform; calculate the product of the effective value of the voltage of the surgical site, the effective value of the output current, and the cosine value of the phase difference to obtain the active power.

[0015] In an energy surgical device provided by an embodiment, the control device is further configured to:

[0016] Compare the magnitude of the active power with a preset power. When the active power is less than the preset power, control the high - frequency generator to increase the frequency - converted energy; when the active power is greater than the preset power, control the high - frequency generator to reduce the frequency - converted energy.

[0017] In an energy surgical device provided by an embodiment, the control device is further configured to:

[0018] Calculate the effective value of the voltage of the surgical site according to the voltage of the surgical site;

[0019] Calculate the effective value of the output current of the output current according to the output current;

[0020] Calculate the impedance of the surgical site according to the active power, the effective value of the voltage of the surgical site, the effective value of the output current, and the angular frequency.

[0021] In an energy surgical device provided by an embodiment, the control device calculates the impedance of the surgical site according to the active power, the effective value of the voltage of the surgical site, the effective value of the output current, and the angular frequency, including:

[0022] Based on the active power, the effective value of the voltage of the surgical site, and the effective value of the output current, the real part and the imaginary part of the distributed capacitance of the output device and the equivalent impedance of the surgical site are calculated;

[0023] Based on the effective value of the voltage and a preset relational expression between the distributed capacitance of the output device and the effective value of the voltage, the capacitance value of the distributed capacitance of the output device is calculated;

[0024] Based on the real part and the imaginary part of the equivalent impedance, the capacitance value of the distributed capacitance of the output device, and the angular frequency, the impedance of the surgical site is calculated.

[0025] In an energy surgical device provided by an embodiment, the control device is further configured to:

[0026] Determine whether the impedance of the surgical site exceeds a preset impedance safety range. If so, stop outputting the frequency - converted energy to the surgical site; or,

[0027] Obtain the resistance of the surgical site based on the impedance of the surgical site, and determine whether the resistance of the surgical site exceeds a preset resistance safety range. If so, stop outputting the frequency - converted energy to the surgical site.

[0028] In an energy surgical device provided by an embodiment, the output current is an output current vector; the control device calculates the voltage across the transmission cable based on the distributed resistance of the transmission cable, the distributed inductance of the transmission cable, the angular frequency of the frequency - converted energy, and the output current, including:

[0029] Based on the distributed resistance of the transmission cable, the distributed inductance of the transmission cable, and the angular frequency of the frequency - converted energy, calculate the equivalent impedance of the transmission cable;

[0030] Calculate the product of the equivalent impedance of the transmission cable and the output current vector to obtain the voltage across the transmission cable.

[0031] An embodiment provides a method for detecting the active power of an energy surgical device. The energy surgical device includes: a high - frequency generator, a transmission cable, an output device, and a detection device; the high - frequency generator is connected to the output device through the transmission cable; the method includes:

[0032] Obtain the output voltage and the output current of the frequency - converted energy generated by the high - frequency generator detected by the detection device;

[0033] Based on the distributed resistance of the transmission cable, the distributed inductance of the transmission cable, the angular frequency of the frequency - converted energy, and the output current, calculate the voltage across the transmission cable;

[0034] Calculate the voltage of the surgical site based on the output voltage and the voltages at both ends of the transmission cable;

[0035] Calculate the active power of the frequency-converted energy received at the surgical site based on the voltage of the surgical site and the output current.

[0036] In the method provided by an embodiment, it further includes:

[0037] Calculate the effective value of the voltage of the surgical site based on the voltage of the surgical site;

[0038] Calculate the effective value of the output current of the output current based on the output current;

[0039] Calculate the impedance of the surgical site based on the active power, the effective value of the voltage of the surgical site, the effective value of the output current, and the angular frequency.

[0040] An embodiment provides a computer-readable storage medium, on which a computer program is stored, and the computer program can be executed by a processor to implement the method as described above.

[0041] The energy surgical device and the active power detection method provided by the present invention, wherein, based on the distributed resistance of the transmission cable, the distributed inductance of the transmission cable, the angular frequency of the frequency-converted energy, and the output current, calculate the voltage at both ends of the transmission cable; based on the output voltage and the voltage at both ends of the transmission cable, calculate the voltage of the surgical site; based on the voltage of the surgical site and the output current, calculate the active power of the frequency-converted energy received at the surgical site. It can be seen that during the calculation of the active power, the influence of the distributed resistance and distributed inductance of the transmission cable is fully considered, improving the accuracy of the active power detection. Description of the Drawings

[0042] Figure 1 It is a structural block diagram of an embodiment of the energy surgical device provided by the present invention;

[0043] Figure 2 It is a flowchart of an embodiment of the active power detection method provided by the present invention;

[0044] Figure 3 It is a structural schematic diagram of an embodiment of the output device;

[0045] Figure 4 It is a structural schematic diagram of another embodiment of the output device;

[0046] Figure 5 It is an equivalent circuit of the high-frequency generator, the transmission cable, the output device, and the surgical site;

[0047] Figure 6 The equivalent circuit diagram of the human tissue at the surgical site is equivalent to a series RLC network;

[0048] Figure 7 The waveform diagram of the calculated value of U3 and the actual detected value of U3 obtained by matlab simulation;

[0049] Figure 8 The schematic diagram of the calculated value of the active power P obtained by matlab simulation and the detected value of the active power at both ends of the equivalent resistance of the surgical site;

[0050] Figure 9 The flowchart of the first embodiment of the method for calculating the impedance of the surgical site;

[0051] Figure 10 The schematic diagram of the calculated value of the impedance of the surgical site and the detected value of the impedance of the surgical site obtained by matlab simulation. Detailed implementation manners

[0052] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

[0053] In the process of calculating the active power of the present invention, the influence of the distributed resistance and distributed inductance of the transmission cable is considered. For the device with electrocoagulation function, the influence of the capacitance (parasitic capacitance) generated by its output device is also considered. Therefore, the calculated active power is more accurate. The following will be described in detail through some embodiments.

[0054] As Figure 1 shown, the energy surgical device provided by the present invention includes: a high-frequency generator 30, a transmission cable 40, an output device 50, a detection device 20, and a control device 10. Among them, the high-frequency generator 30 is connected to the output device 50 through the transmission cable 40.

[0055] The high-frequency generator 30 is used to generate frequency-converted energy, that is, high-frequency energy, usually high-frequency sine waves. For example, the high-frequency generator 30 may include a power supply circuit, a boost circuit, and an inverter circuit. The power supply circuit can be used to convert external alternating current into stable direct current to supply power to the energy surgical device. The power supply circuit can adopt a switching power supply, for example. The boost circuit is used to boost the direct current output by the power supply circuit. The inverter circuit is used to invert the boosted direct current into frequency-converted energy, such as high-frequency sine waves (such as sine waves, cosine waves), etc. The inversion frequencies of different energy surgical devices may be different. For example, energy surgical devices include high-frequency surgical devices, radiofrequency surgical devices, plasma surgical devices, ultrasonic surgical devices, electrocoagulation biopsy devices, electrocoagulation shaving devices, etc. For electrocoagulation biopsy devices, the inversion frequency can be between 100KHz and 4000KHz. For high-frequency surgical devices, such as high-frequency electrosurgical knives, the inversion frequency can be about 1.4MHz. For plasma surgical devices, the inversion frequency can be about 100KHz. For ultrasonic surgical devices, the inversion frequency can be about 20 - 50KHz.

[0056] The transmission cable 40 is used to transmit frequency-converted energy. In this embodiment, specifically, it transmits high-frequency sine waves, and it can adopt a transmission cable.

[0057] The output device 50 is used to output frequency-converted energy to the surgical site, and it can be various tools, such as a rotary cutting electrocoagulation needle tube (see Figure 3 ), an electrocoagulation shaving knife (see Figure 4 ), etc.

[0058] In some embodiments, the energy surgical device further includes an electrode, etc. The electrode is used to attach to the human body. After the high-frequency sine wave passes through the human surgical site, it can form a loop through the electrode.

[0059] The detection device 20 is used to detect the output voltage U1 and output current I1 of the frequency-converted energy generated by the high-frequency generator 30. In this embodiment, the detection device 20 includes a voltage transformer PT and a current transformer CT. The voltage transformer PT is used to collect the output voltage U1 of the frequency-converted energy generated by the high-frequency generator 30. The current transformer CT is used to collect the output current I1 of the frequency-converted energy generated by the high-frequency generator 30.

[0060] The control device 10 is used to calculate the active power P of the frequency-converted energy through the acquired data, that is, the power of the energy applied to the surgical site. The specific process can be as Figure 2 shown, including the following steps:

[0061] Step 1: The control device 10 acquires the output voltage U1 and output current I1 of the frequency-converted energy generated by the high-frequency generator 30 detected by the detection device 20. For example, the output voltage U1 collected by the voltage transformer PT is transmitted to the control device 10. The output current I1 collected by the current transformer CT is also transmitted to the control device 10.

[0062] Step 2: The control device 10 calculates the voltage U2 across the transmission cable 40 based on the distributed resistance R1 of the transmission cable 40, the distributed inductance L1 of the transmission cable 40, the angular frequency w of the frequency-converted energy (the angular frequency of the high-frequency energy on the transmission cable 40), and the output current I1. The reason for calculating the voltage U2 across the transmission cable 40 is to calculate the voltage U3 across the surgical site 60. The distributed resistance R1 and distributed inductance L1 of the transmission cable 40 are preset, that is, known, and can be obtained through an impedance analyzer.

[0063] For the case where the output device 50 is a rotary cutting and electrocoagulation needle tube, as Figure 3 shown, usually the rotary cutting and electrocoagulation needle tube (handle) includes an inner needle tube and an outer needle tube sleeved together, and the surface of the needle tube is coated with an insulating material, just forming a capacitance model. For the case where the output device 50 is an electrocoagulation shaver, as Figure 4 shown, the shaver is also composed of an inner needle tube and an outer needle tube sleeved together, and the surface of the needle tube is coated with an insulating material, which will also form a capacitance model.

[0064] Since there is radio frequency energy on the needle tube, it will be found by actual oscilloscope testing that at a fixed frequency, this capacitance changes with the change of the radio frequency energy voltage. Therefore, the influence of the parasitic capacitance of the output device 50 needs to be considered.

[0065] The equivalent circuit of the high-frequency generator 30, the transmission cable 40, the output device 50 and the surgical site 60 is as Figure 5 shown, including: an equivalent power supply (the output terminal of the high-frequency generator 30), the distributed resistance R1 of the transmission cable 40, the distributed inductance L1 of the transmission cable 40, the distributed capacitance C2 of the output device, and the impedance Z of the surgical site 60. The positive pole of the equivalent power supply is connected to one end of the distributed inductance L1 through the distributed resistance R1, the other end of the distributed inductance L1 is connected to one end of the distributed capacitance C2 and one end of the impedance Z, and the other ends of the distributed capacitance C2 and the impedance Z are both connected to the negative pole of the equivalent power supply. It can be seen that this embodiment also considers the influence of the distributed capacitance of the output device 50 on the calculation of the active power, improving the accuracy.

[0066] Since the frequency-converted energy is usually output in the form of a sine wave, the output voltage U1 and output current I1 collected by the detection device 20 are both sine wave waveforms. In this embodiment, the active power P is calculated in the form of a vector. Specifically, the output voltage U1 is an output voltage vector, including a first array after analog-to-digital sampling of the output voltage waveform in one period. For example, after the voltage transformer collects the output voltage U1 and then performs analog-to-digital conversion, a first array is obtained. The first array contains instantaneous output voltages (array elements) corresponding to multiple different moments in one cycle. The sampling of these instantaneous output voltages conforms to the Nyquist sampling theorem. The output current I1 is an output current vector, including a second array after analog-to-digital sampling of the output current waveform in one period. For example, after the current transformer collects the output current I1 and then performs analog-to-digital conversion, a second array is obtained. The second array contains instantaneous output currents (array elements) corresponding to multiple different moments in one cycle. The sampling of these instantaneous output currents conforms to the Nyquist sampling theorem.

[0067] In the frequency-converted energy, the frequency f is known, so the angular frequency w is also known, w = 2πf. In this step 2, the control device 10 can specifically calculate the equivalent impedance Z_line of the transmission cable according to the distributed resistance R1 of the transmission cable, the distributed inductance L1 of the transmission cable, and the angular frequency w of the frequency-converted energy. The equivalent impedance Z_line can be specifically calculated using the following formula: Z_line = R1 + i×w×L1. Where i is the imaginary unit.

[0068] Furthermore, the control device 10 calculates the product of the equivalent impedance Z_line of the transmission cable and the output current vector to obtain the voltage U2 at both ends of the transmission cable. That is, according to KCL, the current passing through R1 and L1 is also I1. Then the voltage U2 at both ends of R1 and L1 is:

[0069]

[0070] Specifically, the equivalent impedance Z_line is a complex number. Therefore, when calculating the product of the equivalent impedance Z_line and the output current vector , the modulus of this array can be specifically multiplied by each array element of the second array, and then each array element of the second array is delayed by the included angle of the impedance complex number to obtain U2.

[0071] Step 3: The control device 10 calculates the voltage U3 at the surgical site according to the output voltage U1 and the voltage U2 at both ends of the transmission cable. That is, according to KVL, the voltage U3 at both ends of the impedance (impedance of human tissue) Z at the surgical site is:

[0072] U3 = U1 - U2, that is,

[0073] It can be built with MATLAB Figure 5Simulate the equivalent circuit model shown to verify the accuracy of U3. As Figure 6 shown, assume that the human tissue at the surgical site is a series RLC network; the frequency-converted energy is a sine wave with an amplitude of 200V, a frequency of 5MHz, and an initial phase of 0; R1 is 2Ω, L1 is 3.3e-9H; C2 is 100e-12F; Z is a network composed of 50e-6F, 50Ω, and 1e-6H; use MATLAB to build this circuit model for simulation. The waveforms of U3 obtained by simulation calculation and the actual detected U3 are as Figure 7 shown.

[0074] Among them, the blue waveform is the actually detected U3, and the yellow waveform is the U3 calculated by formula 1. It can be seen from the figure that the calculated U3 is exactly the same as the actually detected U3. Changing the values of R1 and L1, the simulation results are still consistent. Therefore, the voltage U3 at the surgical site calculated by the above method is very accurate.

[0075] It can be seen from formula 1 that the voltage U3 at the surgical site is calculated from the output voltage U1, the output voltage I1, and several other parameters. The vectors of the output voltage U1 and the output voltage I1 are represented in the form of an array. Then the voltage U3 at the surgical site is also a vector, which can be called the voltage vector at the surgical site. This voltage vector can also be represented by an array, that is, the voltage vector at the surgical site includes a third array calculated based on the first array and the second array.

[0076] Step 4: The control device 10 calculates the active power P of the frequency-converted energy received at the surgical site according to the voltage U3 at the surgical site and the output current I1, that is, the active power of the energy actually received at the surgical site is obtained. It can be seen that during the calculation of the active power, the influence of the distributed resistance and distributed inductance of the transmission cable is fully considered, improving the accuracy of the active power detection.

[0077] There are various ways to specifically calculate the active power P. Two examples are given below for illustration.

[0078] In the first method, the control device 10 uses the relatively conventional fast Fourier transform to calculate the active power P. Specifically, the control device 10 calculates the phase difference θ between the voltage U3 at the surgical site and the output current I1 (that is, the angle between the vector U3 and the vector I1), the root mean square value rms(U3matrix) of the voltage of the voltage U3 at the surgical site, and the root mean square value rms(I1matrix) of the output current through the fast Fourier transform (FFT); calculate the product of the root mean square value rms(U3matrix) of the voltage of the voltage U3 at the surgical site, the root mean square value rms of the output current, and the cosine value cos(θ) of the phase difference to obtain the active power P.

[0079] In other embodiments, the wavelet algorithm can be used to replace the FFT algorithm. The specific process is the same as above and will not be elaborated here.

[0080] The fast Fourier transform involves complex number operations. The complex calculation process results in a slow calculation speed, and it requires the number of sampling points to be 2^N points. Therefore, the second, simpler and faster method is adopted in this embodiment.

[0081] Second method: The control device 10 calculates the active power P using the principle of the inner product of vectors. Specifically, the control device 10 calculates the inner product of the voltage vector U3 and the output current vector I1 at the surgical site according to the third array and the second array; divides this inner product by the length N of the second array to obtain the active power P. That is, the active power P is calculated according to the following formula.

[0082]

[0083] The length of each array (the number of array elements) is known. In this embodiment, the lengths of the first array, the second array, and the third array are the same, all N.

[0084] The specific derivation process of Formula 2 is elaborated in detail below. According to the vector inner product formula, the following formula 3 can be obtained.

[0085] Formula 3.

[0086]

[0087] Among them, the result output by the sum function is the sum of the products of the corresponding elements of the third array and the second array. The result output by the norm function is the result of first squaring the array elements, then summing them up, and finally taking the square root. θ represents the angle between the vector and the vector That is, the phase difference between the voltage and the current.

[0088] The calculation method of the effective value of the array is to first square and sum the array elements, then calculate the average value, and then take the square root. Based on this, the relationship between the calculation method of the norm function and the calculation method of the effective value is shown in the following Formulas 4 and 5.

[0089] norm(U3matrix) = rms(U3matrix) × sqrt(N) …… Formula 4.

[0090] norm(I1matrix) = rms(I1matrix) × sqrt(N) …… Formula 5.

[0091] Among them, the rms function represents the calculation of the effective value. rms(U3matrix) is the effective value of the voltage of the surgical site voltage U3, and rms(I1matrix) is the effective value of the output current. The Sqrt function represents the square root operation.

[0092] Combining formulas 3, 4, and 5 gives formula 6.

[0093] sum(U3matrix×I1matrix) = rms(U3matrix)×sqrt(N)×rms(I1matrix)×sqrt(N)×cos(θ) …… formula 6.

[0094] The calculation method of the active power P is as follows:

[0095] P = rms(U3matrix)×rms(I1matrix)×cos(θ) …… formula 7.

[0096] Combining formulas 6 and 7 gives:

[0097]

[0098] Similarly, Matlab can be used to simulate the calculation of the active power P to judge its accuracy. Specifically, through the POWER module of Matlab, the active power P of U3 and I1 can be calculated, and through the RMS module of Matlab, the power at both ends of the equivalent resistance of Z can be calculated, as Figure 8 shown. It can be seen that the active power P (270.7) of U3 and I1 is the same as the active power (270.7) directly monitored at both ends of the equivalent resistance of Z. The active power P calculated by the second method is very accurate. Moreover, this calculation method excludes the influence of the parasitic capacitance of the output device 50. The calculation formula and process are simple, without complex operations, and the calculation process is fast, which is suitable for real-time calculation of the active power P during the operation of the energy surgical device. That is, in this embodiment, Figure 2 the process shown can be carried out in real time, so as to obtain the real-time active power P.

[0099] The obtained active power P is equivalent to the true heating power of the surgical site. The control device 10 can perform a control adjustment similar to PID on the calculated active power P and the set power, that is, calculate the true heating power of the human tissue and then achieve constant power control, so as to effectively coagulate blood without damaging the tissue. Specifically, the control device 10 can compare the magnitude of the active power P with the preset power. When the active power P is less than the preset power, the control device 10 controls the high-frequency generator 30 to increase the frequency-based energy; when the active power P is greater than the preset power, the control device 10 controls the high-frequency generator 30 to reduce the frequency-based energy; in this way, the heating power of the surgical site can be maintained at the preset power to achieve constant power control. The preset power can be set by the system or by the user, such as the power set in the UI interface. Taking the latter as an example, the energy surgical device can further include a human-computer interaction device, and the human-computer interaction device can receive the power input or selected by the user, and this power is the preset power.

[0100] The control device 10 can also calculate the impedance Z of the surgical site. Specifically, as Figure 9 shown, the following steps can be included:

[0101] Step 5: The control device 10 calculates the root mean square value rms(U3matrix) of the voltage of the surgical site according to the voltage U3 of the surgical site. Specifically, it first sums the squares of the array elements of the third array, then calculates the average value, and then takes the square root. The control device 10 calculates the root mean square value rms(I1matrix) of the output current according to the output current I1. Specifically, it first sums the squares of the array elements of the second array, then calculates the average value, and then takes the square root.

[0102] Step 6: The control device 10 calculates the impedance Z of the surgical site according to the active power P, the root mean square value rms(U3matrix) of the voltage of the surgical site, the root mean square value rms(I1matrix) of the output current, and the angular frequency w. Specifically, the control device 10 can calculate the real part R and the imaginary part x of the equivalent impedance of the distributed capacitance C2 of the output device and the surgical site according to the active power P, the root mean square value rms(U3matrix) of the voltage of the surgical site, and the root mean square value rms(I1matrix) of the output current. For example, first calculate the cosine value cos(θ) of the phase difference according to Formula 7:

[0103] cos(θ) = P / (rms(U3matrix) × rms(I1matrix))... Formula 8.

[0104] According to the cosine value cos(θ) of the phase difference, the sine value sin(θ) of the phase difference can be calculated. Furthermore, according to the network impedance calculation method, the real part R and the imaginary part x of the equivalent impedance of the distributed capacitance C2 and the surgical site can be calculated:

[0105] R = rms(U3 matrix ) / rms(I1 matrix ) × cos(θ)

[0106] x = rms(U3 matrix ) / rms(I1 matrix ) × sin(θ) …… Equation 9.

[0107] According to Figure 6 it is known that to calculate the impedance Z of the surgical site, the value of the capacitance C2 needs to be known. Since it is actually found that the value of C2 changes with the voltage of the energy varying with frequency, this can be used to fit the relationship between the capacitance C2 and the voltage magnitude through the material curve of the output device (such as the needle tube material curve), that is, the relationship between the distributed capacitance C2 of the output device and the rms voltage value rms(U3matrix) is known and can be preset in the energy surgical device. In one embodiment, the preset relationship is as follows:

[0108] C2 = K1 * rms(U3 matrix ) 2 + K2 * rms(U3 matrix ) + b …… Equation 10.

[0109] That is, the control device 10 can calculate the capacitance value of the distributed capacitance C2 of the output device according to the rms voltage value rms(U3matrix) and the preset relationship between the distributed capacitance C2 of the output device and the rms voltage value rms(U3matrix).

[0110] Furthermore, the control device 10 calculates the impedance Z of the surgical site according to the real part R, the imaginary part x of the equivalent impedance, the capacitance value of the distributed capacitance C2 of the output device, and the angular frequency w. Specifically, according to Equations 9 and 10 and the parallel impedance calculation, it can be obtained that:

[0111] i × w × C2 + 1 / Z = 1 / (R + i × x) …… Equation 11.

[0112] The impedance Z of the surgical site can be obtained from Equation 11.

[0113] Similarly, the impedance Z of the surgical site can be calculated through matlab simulation and compared with the actual impedance as Figure 10 shown. According to Figure 10 it is known that the magnitudes of the two are the same (both are 50), so the impedance Z of the surgical site calculated by the present invention is very accurate.

[0114] According to analog electronics knowledge, circuit loads are divided into three types: resistors, inductors, and capacitors. Inductors and capacitors constitute the imaginary part x of impedance, and resistors constitute the real part R of impedance. The impedance formula is Z = R + i×x. According to this formula, the control device 10 can obtain the resistance of the surgical site, that is, the resistance of the surgical site can be obtained based on the impedance Z of the surgical site.

[0115] It can be seen that the present invention can accurately monitor the impedance and / or resistance of human tissue (surgical site) under high-frequency energy output, so as to control whether energy is output. Continuous output of high-frequency energy may cause excessive charring, excessive adhesion or even carbonization of the surgical site. Therefore, certain safety measures are required. The control device 10 can determine whether the impedance Z of the surgical site exceeds the preset impedance safety range. If so, it stops outputting frequency-modulated energy to the surgical site. The impedance safety range can be set according to actual needs or experience, etc. Of course, the impedance Z of the surgical site can also be used for safety protection. The control device 10 obtains the resistance of the surgical site based on the impedance Z of the surgical site, and determines whether the resistance of the surgical site exceeds the preset resistance safety range. If so, it stops outputting frequency-modulated energy to the surgical site. Similarly, the resistance safety range can be set according to actual needs or experience, etc. The control device 10 controls the energy surgical device to stop outputting frequency-modulated energy to the surgical site. For example, it can make the high-frequency generator 30 stop generating frequency-modulated energy, and / or disconnect the circuit between the high-frequency generator 30 and the output device 50, etc.

[0116] The control device 10 may include a processor, and the method shown may be mainly executed by the processor Figure 2 and 9 or rather, the various functions of the above-mentioned control device 10 are mainly executed by the processor. The processor can implement these functions by executing a computer program, and the computer program can be stored on a computer-readable storage medium. The present invention also provides a computer-readable storage medium, on which a computer program is stored, and the computer program can be executed by the processor to implement the various functions of the foregoing control device 10.

[0117] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An energy surgery device, characterized in that: include: High frequency generator, transmission cable, output device, detection device and control device; The high frequency generator is connected to the output device via the transmission cable; The high frequency generator is used to generate frequency energy; The output device is used to output the frequencyized energy to the surgical site; The detection device is used to detect the output voltage U1 and output current I1 of the frequency-converted energy generated by the high-frequency generator; The control device is used for: The voltage U2 at both ends of the transmission cable is calculated based on the distributed resistance R1 of the transmission cable, the distributed inductance L1 of the transmission cable, the angular frequency w of the frequency-converted energy, and the output current I1; Calculate the voltage U3 of the surgical site according to the output voltage U1 and the voltage U2 at both ends of the transmission cable; The active power P of the frequency-converted energy received by the surgical site is calculated based on the voltage U3 of the surgical site and the output current I1.

2. The energy surgery device according to claim 1, characterized in that: The control device calculates the active power P of the frequency-converted energy received by the surgical site according to the voltage U3 of the surgical site and the output current I1, including: The output voltage U1 is an output voltage vector, including a first array of an output voltage waveform of one cycle after analog-to-digital sampling; the output current I1 is an output current vector, including a second array of an output current waveform of one cycle after analog-to-digital sampling; the voltage U3 of the surgical site is a voltage vector of the surgical site, including a third array calculated based on the first array and the second array; the inner product of the voltage vector U3 of the surgical site and the output current vector I1 is calculated based on the third array and the second array; the inner product is divided by the length N of the second array to obtain the active power P; or, The phase difference θ between the voltage U3 at the surgical site and the output current I1, the voltage effective value rms (U3matrix) of the surgical site voltage U3 and the output current effective value rms (I1matrix) are calculated by fast Fourier transform; the product of the voltage effective value rms (U3matrix) of the surgical site voltage U3, the output current effective value rms and the cosine value cos(θ) of the phase difference is calculated to obtain the active power P.

3. The energy surgery device according to claim 1 or 2, characterized in that: The control device is also used for: comparing the active power P with the preset power, and when the active power P is less than the preset power, controlling the high frequency generator to increase the frequencyized energy; When the active power P is greater than the preset power, the high frequency generator is controlled to reduce the frequency-converted energy.

4. The energy surgery device according to claim 1, characterized in that: The control device is also used for: The voltage effective value rms (U3matrix) of the voltage at the surgical site is calculated according to the voltage U3 at the surgical site; An output current effective value rms (I1matrix) of the output current is calculated according to the output current I1; The impedance Z of the surgical site is calculated based on the active power P, the voltage effective value rms (U3matrix) of the surgical site voltage, the output current effective value rms (I1matrix) and the angular frequency w.

5. The energy surgery device according to claim 4, characterized in that: The control device calculates the impedance Z of the surgical site according to the active power P, the voltage rms value (U3matrix) of the surgical site voltage, the output current rms value (I1matrix) and the angular frequency w, including: According to the active power P, the voltage effective value rms (U3matrix) of the voltage at the surgical site, and the output current effective value rms (I1matrix), the real part R and the imaginary part x of the equivalent impedance between the distributed capacitance C2 of the output device and the surgical site are calculated; According to the voltage effective value rms (U3matrix) and a preset relationship between the distributed capacitance C2 of the output device and the voltage effective value rms (U3matrix), the capacitance value of the distributed capacitance C2 of the output device is calculated; The impedance Z of the surgical site is calculated based on the real part R, the imaginary part x of the equivalent impedance, the capacitance value of the distributed capacitance C2 of the output device, and the angular frequency w.

6. The energy surgery device according to claim 4 or 5, characterized in that: The control device is also used for: Determine whether the impedance Z of the surgical site exceeds a preset impedance safety range, and if so, stop outputting the frequencyized energy to the surgical site; or, The resistance of the surgical site is obtained according to the impedance Z of the surgical site, and it is determined whether the resistance of the surgical site exceeds a preset resistance safety range. If so, the output of the frequencyized energy to the surgical site is stopped.

7. The energy surgery device according to claim 1, characterized in that: The output current I1 is an output current vector; the control device calculates the voltage U2 at both ends of the transmission cable according to the distributed resistance R1 of the transmission cable, the distributed inductance L1 of the transmission cable, the angular frequency w of the frequency-converted energy, and the output current I1, including: The equivalent impedance of the transmission cable is calculated based on the distributed resistance R1 of the transmission cable, the distributed inductance L1 of the transmission cable and the angular frequency w of the frequency-converted energy; The product of the equivalent impedance of the transmission cable and the output current vector is calculated to obtain the voltage U2 at both ends of the transmission cable.

8. A method for detecting active power of an energy surgery device, the energy surgery device comprising: High frequency generator, transmission cable, output device and detection device; The high frequency generator is connected to the output device via the transmission cable; the method comprising: Acquire the output voltage U1 and output current I1 of the frequencyized energy generated by the high frequency generator detected by the detection device; The voltage U2 at both ends of the transmission cable is calculated based on the distributed resistance R1 of the transmission cable, the distributed inductance L1 of the transmission cable, the angular frequency w of the frequency-converted energy, and the output current I1; Calculate the voltage U3 of the surgical site according to the output voltage U1 and the voltage U2 at both ends of the transmission cable; The active power P of the frequency-converted energy received by the surgical site is calculated based on the voltage U3 of the surgical site and the output current I1.

9. The method according to claim 8, characterized in that Also includes: The voltage effective value rms (U3matrix) of the voltage at the surgical site is calculated according to the voltage U3 at the surgical site; An output current effective value rms (I1matrix) of the output current is calculated according to the output current I1; The impedance z of the surgical site is calculated based on the active power P, the voltage effective value rms (U3matrix) of the surgical site voltage, the output current effective value rms (I1matrix) and the angular frequency w.

10. A computer-readable storage medium, characterized in that: A computer program is stored on the medium, and the computer program can be executed by a processor to implement the method according to claim 8 or 9.

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