A high-bandwidth current detection extraction coil sensor

Abstract

The present invention provides a high-bandwidth current detection extraction coil sensor, which relates to the technical field of current measurement of wide-bandgap semiconductor devices. It includes: a single-turn current extraction coil, which is used to generate a voltage according to the input current by using the electromagnetic induction law. The single-turn current extraction coil includes a single-turn copper coil; a coil terminal matching resistor Rd, which is connected to the single-turn current extraction coil and is used to perform impedance matching on the voltage to generate a matched voltage signal; a signal processing circuit, which is respectively connected to the single-turn current extraction coil and the coil terminal matching resistor Rd, and is used to restore the matched voltage signal and output the restored current to achieve current detection. The single-turn copper coil reduces the parasitic capacitance and parasitic inductance, improves the current detection bandwidth, and avoids the interference of inserted parasitic inductance when measuring the current of fast GaN devices; by adopting the single-turn current extraction coil, the coil terminal matching resistor Rd and the signal processing circuit, the manufacturing cost of the high-bandwidth current detection extraction coil sensor is relatively low.

Description

Technical Field

[0001] The present invention relates to the technical field of current measurement of wide-bandgap semiconductor devices, and particularly to a high-bandwidth current detection extraction coil sensor. Background Art

[0002] Gallium nitride (GaN) devices are suitable for high-frequency power converters due to their excellent switching performance. In order to maximize the performance of GaN devices, it is necessary to study the switching characteristics of GaN devices. The switching current is a basic parameter for evaluating the switching characteristics and verifying GaN devices. However, for fast GaN devices, the measurement of the switching current is a major challenge. Since fast GaN devices have low capacitance and low parasitic inductance, fast GaN devices have a very fast switching speed. The edge time t r of a fast GaN device may be less than 1 ns. According to the expression of the measurement bandwidth BW it can be known that a measurement bandwidth of at least 350 MHz is required. In addition, due to the fast switching speed, small threshold voltage safety range, and parasitic sensitivity of fast GaN devices, when measuring the current of fast GaN devices, the conditions of having a high bandwidth and not introducing too much parasitic inductance into the power converter loop should be met.

[0003] Currently, a Rogowski coil current sensor is used to detect the current of fast GaN devices. The Rogowski coil current sensor consists of a coil and an integrator; the coil generally adopts a circular spiral structure, and the coil has advantages such as being less affected by the position of the internal current-carrying conductor and having no magnetic saturation problem. However, in order to improve the sensitivity and accuracy of the Rogowski coil current sensor, a multi-turn coil is generally used, but the multi-turn coil will cause larger inserted parasitic inductance and parasitic capacitance, which limits the measurement bandwidth, resulting in a lower bandwidth, and causing inserted parasitic inductance interference when measuring the current of fast GaN devices; the commonly used model of the Rogowski coil current sensor is TRCP0600, and the price of this model of the Rogowski coil current sensor is relatively expensive, making the manufacturing cost of the Rogowski coil current sensor relatively high. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a high-bandwidth current detection extraction coil sensor to solve the problems of the lower bandwidth of the Rogowski coil current sensor, the inserted parasitic inductance interference generated when measuring the current of fast GaN devices, and the relatively high manufacturing cost of the Rogowski coil current sensor.

[0005] To solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

[0006] The present invention provides a high-bandwidth current detection extraction coil sensor, including a single-turn current extraction coil, a coil terminal matching resistor Rd and a signal processing circuit;

[0007] A single-turn current extraction coil, which is used to generate a voltage according to the input current by using the law of electromagnetic induction. The single-turn current extraction coil includes a single-turn copper coil;

[0008] The coil terminal matching resistor R d , which is connected to the single-turn current extraction coil and is used to perform impedance matching on the voltage to generate a matched voltage signal;

[0009] The signal processing circuit is respectively connected to the single-turn current extraction coil and the coil terminal matching resistor R d and is used to restore the matched voltage signal and output the restored current to achieve current detection.

[0010] In some embodiments, the high-bandwidth current detection extraction coil sensor further includes an output current terminal, a measurement port V out1 and a measurement port V out2 ;

[0011] The output current terminal is respectively connected to the signal processing circuit and the measurement port V out2 and is used to output the restored current;

[0012] The measurement port V out1 , which is respectively connected to the single-turn current extraction coil, the coil terminal matching resistor R d , and the signal processing circuit, and is used to perform a frequency scan on the single-turn current extraction coil to obtain the bandwidth of the single-turn current extraction coil;

[0013] The measurement port V out2 , which is connected to the signal processing circuit and is used to perform a frequency scan on the high-bandwidth current detection extraction coil sensor to obtain the bandwidth of the high-bandwidth current detection extraction coil sensor.

[0014] In some embodiments, the signal processing circuit includes a voltage follower, a passive RC integrator, a resistor R1, and an active integrator;

[0015] The positive input terminal of the voltage follower is respectively connected to one end of the coil terminal matching resistor R d , one end of the measurement port V out1 , and the single-turn current extraction coil. The negative input terminal of the voltage follower is connected to the passive RC integrator, and the output terminal of the voltage follower is connected to the passive RC integrator. The voltage follower is used to perform a following operation on the matched voltage signal and output the followed voltage signal;

[0016] The passive RC integrator is respectively connected to the other end of the resistor R1, the other end of the coil terminal matching resistor R d , and the measurement port V out1The other end is connected to a single-turn current extraction coil and an active integrator, which are used to filter and integrate the subsequent voltage signal in sequence and output the integrated current signal;

[0017] The active integrator is respectively connected to one end of the resistor R1, the measurement port V out2 , and the output current terminal, and is used to restore the integrated current signal and output the restored current to achieve current detection;

[0018] The other end of the resistor R1 is respectively connected to the other end of the measurement port V out1 , the other end of the coil terminal matching resistor R d , and the single-turn current extraction coil.

[0019] In some embodiments, the passive RC integrator includes a resistor R0 and a capacitor C0;

[0020] One end of the resistor R0 is respectively connected to the output end of the voltage follower and the inverting input end of the voltage follower. The other end of the resistor R0 is connected to one end of the capacitor C0 and the active integrator. One end of the capacitor C0 is connected to the active integrator. The other end of the capacitor C0 is respectively connected to the other end of the resistor R1, the other end of the coil terminal matching resistor R d , the other end of the measurement port, and the single-turn current extraction coil.

[0021] In some embodiments, the active integrator includes an operational amplifier, a resistor R2, and a capacitor C1;

[0022] The non-inverting input end of the operational amplifier is respectively connected to the other end of the resistor R0 and one end of the capacitor C0. The inverting input end of the operational amplifier is respectively connected to one end of the resistor R1, one end of the resistor R2, and one end of the capacitor C1. The output end of the operational amplifier is respectively connected to the other end of the resistor R2, the other end of the capacitor C1, the other end of the measurement port V out2 , and the output current terminal. One end of the resistor R2 is respectively connected to one end of the capacitor C1 and one end of the resistor R1. The other end of the resistor R2 is respectively connected to the other end of the capacitor C1, the output current terminal, and the other end of the measurement port V out2 . One end of the capacitor C1 is connected to one end of the resistor R1. The other end of the capacitor C1 is connected to the output current terminal and the other end of the measurement port V out2 .

[0023] In some embodiments, the signal processing circuit further includes a resistor R3;

[0024] One end of the resistor R3 is connected to the inverting input end of the voltage follower, and the other end of the resistor R3 is respectively connected to the output end of the voltage follower and one end of the resistor R0.

[0025] In some embodiments, the equivalent circuit of the single-turn current extraction coil includes a mutual inductance M between the single-turn current extraction coil and the current-carrying conductor to be measured. s , a resistor R s , a parasitic inductance L S and a capacitor C s ;

[0026] One end of the mutual inductance M s is connected to one end of the resistor R s . The other end of the mutual inductance M s is respectively connected to the other end of the capacitor C s , the other end of the coil terminal matching resistor R d , the other end of the measurement port V out1 , the other end of the capacitor C0, and the other end of the resistor R1;

[0027] The other end of the resistor R s is connected to one end of the parasitic inductance L S . The other end of the parasitic inductance L S is respectively connected to one end of the capacitor C s , one end of the coil terminal matching resistor R d , one end of the measurement port V out1 , the positive input terminal of the voltage follower. One end of the capacitor C s is respectively connected to one end of the coil terminal matching resistor R d , one end of the measurement port V out1 , the positive input terminal of the voltage follower. The other end of the capacitor C s is respectively connected to the other end of the coil terminal matching resistor R d , the other end of the measurement port V out1 , the other end of the capacitor C0, and the other end of the resistor R1.

[0028] In some embodiments, the power supply port of the voltage follower is grounded.

[0029] In some embodiments, one end of the measurement port V out2 and the power supply port of the operational amplifier are both grounded.

[0030] In some embodiments, the positive output terminal of the single-turn current extraction coil is connected to the current inflow end of the current-carrying conductor to be measured, and the negative output terminal of the single-turn current extraction coil is connected to the current outflow end of the current-carrying conductor to be measured.

[0031] Compared with the prior art, a high-bandwidth current detection and extraction coil sensor provided by the present invention includes a single-turn current extraction coil and a coil terminal matching resistor R dAnd a signal processing circuit; a single-turn current extraction coil, which generates a voltage according to the input current by using the electromagnetic induction law, and the single-turn current extraction coil includes a single-turn copper coil; a coil terminal matching resistor R d , connected to the single-turn current extraction coil, for impedance-matching the voltage to generate a matched voltage signal; a signal processing circuit, respectively connected to the single-turn current extraction coil and the coil terminal matching resistor R d , for restoring the matched voltage signal and outputting the restored current to achieve current detection. In this way, the single-turn copper coil in the single-turn current extraction coil reduces the parasitic capacitance and parasitic inductance, thereby improving the current detection bandwidth and avoiding the interference of inserted parasitic inductance when measuring the current of fast GaN devices; the adopted single-turn current extraction coil, coil terminal matching resistor R d and the signal processing circuit have relatively low prices, making the manufacturing cost of the high-bandwidth current detection extraction coil sensor relatively low. Description of the Drawings

[0032] By referring to the accompanying drawings and reading the detailed description below, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become easily understandable. In the drawings, several embodiments of the present invention are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0033] Figure 1 Schematically shows the structural diagram of the high-bandwidth current detection extraction coil sensor;

[0034] Figure 2 Schematically shows the equivalent circuit of the high-bandwidth current detection extraction coil sensor Figure 1 ;

[0035] Figure 3 Schematically shows the equivalent circuit of the high-bandwidth current detection extraction coil sensor Figure 2 ;

[0036] Figure 4 Schematically shows the equivalent circuit diagram of the single-turn current extraction coil;

[0037] Figure 5 Schematically shows the equivalent circuit of the high-bandwidth current detection extraction coil sensor Figure 3 ;

[0038] Figure 6 Schematically shows the structural diagram of the single-turn current extraction coil;

[0039] Figure 7 Schematically shows the theoretical analysis diagram of the amplitude-frequency and phase-frequency responses of the single-turn current extraction coil;

[0040] Figure 8 Schematically shows a schematic diagram of the theoretical analysis of the amplitude-frequency and phase-frequency responses of a high-bandwidth current detection extraction coil sensor;

[0041] Figure 9 Schematically shows a schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency responses of a single-turn current extraction coil;

[0042] Figure 10 Schematically shows a schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency responses of a high-bandwidth current detection extraction coil sensor. Detailed implementation manners

[0043] The following further describes in detail the implementation manners of the present invention in conjunction with the accompanying drawings and embodiments. The detailed descriptions and drawings of the following embodiments are used to exemplarily illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention. The present invention can be implemented in many different forms, is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

[0044] The following details a high-bandwidth current detection extraction coil sensor in an embodiment of the present invention.

[0045] See Figure 1 as shown, Figure 1 Schematically shows a structural schematic diagram of a high-bandwidth current detection extraction coil sensor. An embodiment of the present invention proposes a high-bandwidth current detection extraction coil sensor, including a single-turn current extraction coil, a coil terminal matching resistor R d and a signal processing circuit;

[0046] The single-turn current extraction coil is used to generate a voltage according to the input current by using the electromagnetic induction law. The single-turn current extraction coil includes a single-turn copper coil;

[0047] The coil terminal matching resistor R d , connected to the single-turn current extraction coil, is used to perform impedance matching on the voltage to generate a matched voltage signal;

[0048] The signal processing circuit is respectively connected to the single-turn current extraction coil and the coil terminal matching resistor R d and is used to restore the matched voltage signal and output the restored current to achieve current detection.

[0049] In this embodiment, the positive output end of the single-turn current extraction coil is connected to the current inflow end of the current-carrying conductor to be measured, and the negative output end of the single-turn current extraction coil is connected to the current output end of the current-carrying conductor to be measured.

[0050] Specifically, before using the high-bandwidth current detection extraction coil sensor to detect current, the positive output terminal of the single-turn current extraction coil in the high-bandwidth current detection extraction coil sensor should be connected to the current inflow end of the current-carrying conductor to be measured, and the negative output terminal should be connected to the current output end of the current-carrying conductor to be measured, so as to detect the current through the connected high-bandwidth current detection extraction coil sensor. Place the high-bandwidth current detection extraction coil sensor on the surface of the current-carrying conductor to be measured, so that the parasitic inductance generated during the current measurement of the current-carrying conductor to be measured is 0, and avoid the interference of the inserted inductance during the current measurement.

[0051] The single-turn current extraction coil uses a single-turn copper coil, which reduces the parasitic capacitance and parasitic inductance, thereby increasing the bandwidth of current detection.

[0052] The high-bandwidth current detection extraction coil sensor of the present invention is a single-turn current extraction coil with high bandwidth and zero insertion inductance set according to the basic principle of Faraday's law of electromagnetic induction, and a signal processing circuit is set. The signal processing circuit processes the matched voltage signal generated by passing through the single-turn current extraction coil and the coil terminal matching resistor R d Finally, the restored current can be obtained. The single-turn copper coil in the single-turn current extraction coil has no iron core, so there is no magnetic saturation phenomenon, and a very large current can be directly measured.

[0053] In this embodiment, the high-bandwidth current detection extraction coil sensor further includes an output current terminal, measurement port V out1 and measurement port V out2 ;

[0054] The output current terminal is respectively connected to the signal processing circuit and measurement port V out2 and is used to output the restored current;

[0055] Measurement port V out1 , which is respectively connected to the single-turn current extraction coil, the coil terminal matching resistor R d , and the signal processing circuit, and is used to perform frequency scanning on the single-turn current extraction coil to obtain the bandwidth of the single-turn current extraction coil;

[0056] Measurement port V out2 , which is connected to the signal processing circuit, and is used to perform frequency scanning on the high-bandwidth current detection extraction coil sensor to obtain the bandwidth of the high-bandwidth current detection extraction coil sensor.

[0057] Figure 2 Schematically shows the equivalent circuit of the high-bandwidth current detection extraction coil sensor Figure 1 , in this embodiment, the signal processing circuit includes a voltage follower, a passive RC integrator, a resistor R1, and an active integrator;

[0058] The positive input terminal of the voltage follower is respectively connected to one end of the coil terminal matching resistor R d and one end of the measurement port V out1 and the single-turn current extraction coil. The negative input terminal of the voltage follower is connected to the passive RC integrator, and the output terminal of the voltage follower is connected to the passive RC integrator. The voltage follower is used to perform a following operation on the matched voltage signal and output the followed voltage signal;

[0059] The passive RC integrator is respectively connected to the other end of the resistor R1, the other end of the coil terminal matching resistor R d and the other end of the measurement port V out1 and the single-turn current extraction coil and the active integrator, and is used to filter and integrate the followed voltage signal in sequence and output the integrated current signal;

[0060] The active integrator is respectively connected to one end of the resistor R1, the measurement port V out2 and the output current terminal, and is used to restore the integrated current signal and output the restored current to achieve current detection;

[0061] The other end of the resistor R1 is respectively connected to the other end of the measurement port V out1 and the other end of the coil terminal matching resistor R d and the single-turn current extraction coil.

[0062] The signal processing circuit includes a passive RC integrator and an active integrator. The anti-interference ability of the voltage signal is enhanced through the passive RC integrator and the active integrator, and ultra-high bandwidth current detection can be achieved.

[0063] Specifically, when the high-bandwidth current detection extraction coil sensor is working, the input current flows from the positive input terminal (i.e., in+) of the single-turn current extraction coil to the negative input terminal (i.e., in-). At this time, according to the electromagnetic induction law, the single-turn current extraction coil generates a voltage at both ends of the positive output terminal (i.e., out+) and the negative output terminal (i.e., out-) of the single-turn current extraction coil. The generated voltage is impedance-matched through the coil terminal matching resistor R d , and then the matched voltage signal generated by the coil terminal matching resistor R d passes through the voltage follower. The voltage follower follows the matched voltage signal to generate a followed voltage signal. The followed voltage signal is filtered and integrated through the passive RC integrator to output an integrated current signal; the integrated current signal passes through the resistor R1 and the active integrator to restore the integrated current signal, and finally the restored current is obtained to achieve complete current detection.

[0064] The function of the voltage follower is to generate a following voltage signal by following the matched voltage signal. The voltage follower has the characteristics of high input impedance and low output impedance, which can isolate the voltage signal, avoid the loss of the voltage signal, and improve the load-carrying capacity of the high-bandwidth current detection extraction coil sensor.

[0065] In this embodiment, the passive RC integrator includes a resistor R0 and a capacitor C0;

[0066] One end of the resistor R0 is respectively connected to the output end of the voltage follower and the inverting input end of the voltage follower. The other end of the resistor R0 is connected to one end of the capacitor C0 and the active integrator. One end of the capacitor C0 is connected to the active integrator. The other end of the capacitor C0 is respectively connected to the other end of the resistor R1, the other end of the coil terminal matching resistor R d and the other end of the measurement port V out1 and the other end of the single-turn current extraction coil.

[0067] Specifically, the following voltage signal passes through the resistor R0 and the capacitor C0 in sequence for filtering and integration, and outputs the integrated current signal.

[0068] In this embodiment, the active integrator includes an operational amplifier, a resistor R2, and a capacitor C1;

[0069] The non-inverting input end of the operational amplifier is respectively connected to the other end of the resistor R0 and one end of the capacitor C0. The inverting input end of the operational amplifier is respectively connected to one end of the resistor R1, one end of the resistor R2, and one end of the capacitor C1. The output end of the operational amplifier is respectively connected to the other end of the resistor R2, the other end of the capacitor C1, and the other end of the measurement port V out2 and the other end of the output current terminal. One end of the resistor R2 is respectively connected to one end of the capacitor C1 and one end of the resistor R1. The other end of the resistor R2 is respectively connected to the other end of the capacitor C1, the output current terminal, and the other end of the measurement port V out2 and the other end. One end of the capacitor C1 is connected to one end of the resistor R1. The other end of the capacitor C1 is connected to the output current terminal and the other end of the measurement port V out2 and the other end.

[0070] Specifically, the current signal after integration through the resistor R1 passes through the operational amplifier, the resistor R2, and the capacitor C1 to restore the integrated current signal, and finally obtains the restored current to achieve complete current detection.

[0071] Figure 3 Schematically shows the equivalent circuit of the high-bandwidth current detection extraction coil sensor Figure 2 , in this embodiment, the signal processing circuit further includes a resistor R3;

[0072] One end of resistor R3 is connected to the inverting input terminal of the voltage follower, and the other end of resistor R3 is respectively connected to the output terminal of the voltage follower and one end of resistor R0.

[0073] Specifically, in a signal processing circuit including a voltage follower, a passive RC integrator, resistor R1, and an active integrator, adding resistor R3 can make the subsequent voltage signal more stable.

[0074] Figure 4 The equivalent circuit diagram of the single-turn current extraction coil is schematically shown. Figure 5 The equivalent circuit of the high-bandwidth current detection extraction coil sensor is schematically shown Figure 3 , see Figure 4 and Figure 5 As shown, in this embodiment, the equivalent circuit of the single-turn current extraction coil includes the mutual inductance M between the single-turn current extraction coil and the current-carrying conductor to be measured s , resistor R s , parasitic inductance L S and capacitor C s ;

[0075] One end of the mutual inductance M s is connected to one end of resistor R s , and the other end of the mutual inductance M s is respectively connected to the other end of capacitor C s , the other end of the coil terminal matching resistor R d , the other end of the measurement port V out1 , the other end of capacitor C0, and the other end of resistor R1;

[0076] The other end of resistor R s is connected to one end of parasitic inductance L S , and the other end of parasitic inductance L S is respectively connected to one end of capacitor C s , the other end of the coil terminal matching resistor R d , the other end of the measurement port V out1 , and the non-inverting input terminal of the voltage follower. One end of capacitor C s is respectively connected to the other end of the coil terminal matching resistor R d , the other end of the measurement port V out1 , and the non-inverting input terminal of the voltage follower. The other end of capacitor C s is respectively connected to the other end of the coil terminal matching resistor R d , the other end of the measurement port V out1 , the other end of capacitor C0, and the other end of resistor R1.

[0077] Specifically, the other end of capacitor C s and the mutual inductance M sThe other ends are all grounded.

[0078] The positive input terminal, i.e., in+, and the negative input terminal, i.e., in-, are used as the inputs of the input current. The input current flows from the positive input terminal, i.e., in+, of the single-turn current extraction coil, through the mutual inductance M s to the negative input terminal, i.e., in-, the resistor R s , the parasitic inductance L S and the capacitor C s , and a voltage is generated across the two ends of the positive output terminal, i.e., out+, and the negative output terminal, i.e., out-, of the single-turn current extraction coil.

[0079] According to the upper limit bandwidth f of the single-turn current extraction coil is calculated H , usually R d >> R s , the expression of the upper limit bandwidth of the above single-turn current extraction coil can be simplified to: The parameters of the single-turn current extraction coil are extracted by using a finite element parasitic parameter extraction tool, and the parameters include the parasitic inductance L S and the capacitor C s . Through the simplified expression of the upper limit bandwidth of the single-turn current extraction coil and the extracted parasitic inductance and capacitor C s parameters, the upper limit bandwidth of the single-turn current extraction coil is calculated. According to the lower limit bandwidth f of the single-turn current extraction coil can be obtained L , and by adjusting R0C0 = R1C1, the passive integrator and the active integrator can be smoothly transitioned.

[0080] Figure 6 The structural diagram of the single-turn current extraction coil is schematically shown. In addition to the single-turn copper coil, the single-turn current extraction coil also includes a printed circuit (Printed Circuit Board, PCB) board and copper vias. The single-turn copper coil includes a first single-turn copper coil, a second single-turn copper coil, a third single-turn copper coil, a fourth single-turn copper coil, a first connecting part single-turn copper coil, a second connecting part single-turn copper coil, and a third connecting part single-turn copper coil. Both the third single-turn copper coil and the fourth single-turn copper coil are square-ring-shaped single-turn coils with openings;

[0081] Two symmetrically arranged circular openings are provided on the PCB board, and the first single-turn copper coil and the second single-turn copper coil are respectively arranged around the two circular openings;

[0082] The third single-turn copper coil is arranged on the PCB board, and the third single-turn copper coil is located to the left of the first single-turn copper coil. The lower surface of the first single-turn copper coil and one end of the opening of the third single-turn copper coil are on the same horizontal plane, and the lower surface of the first single-turn copper coil and one end of the opening of the third single-turn copper coil are connected by the first connecting part single-turn copper coil;

[0083] The fourth single-turn copper coil is disposed on the printed circuit board, and the fourth single-turn copper coil is located to the right of the second single-turn copper coil. The upper surface of the second single-turn copper coil and one end of the opening of the fourth single-turn copper coil are on the same horizontal plane. The upper surface of the second single-turn copper coil and one end of the opening of the fourth single-turn copper coil are connected by the second connecting part single-turn copper coil. The third single-turn copper coil and the fourth single-turn copper coil are symmetrically arranged along the center;

[0084] The other end of the opening of the third single-turn copper coil and the other end of the opening of the fourth single-turn copper coil are connected by the third connecting part single-turn copper coil. The third connecting part single-turn copper coil is located in the middle of the first single-turn copper coil and the second single-turn copper coil.

[0085] The length of the PCB board is 9 mm, the width of the PCB board is 4.5 mm, the diameters of the two copper holes are both 0.9 mm, and the ring widths of the third single-turn copper coil and the fourth single-turn copper coil are both 0.4 mm.

[0086] The input current flows from the positive input end, i.e., in+, of the single-turn current extraction coil to the negative input end, i.e., in-. Voltages are generated at both ends of O+ and O- of the single-turn current extraction coil, i.e., both ends of out+ and out-.

[0087] The single-turn current extraction coil is set with a single-turn copper coil, achieving a bandwidth of up to 884 MHz.

[0088] The length of the PCB board of the single-turn current extraction coil is 9 mm, the width of the PCB board is 4.5 mm, the line width of the single-turn copper coil, i.e., the ring width, is 0.4 mm. The size of the entire single-turn current extraction coil is small, making the installation of the single-turn current extraction coil easy and the parasitic capacitance and parasitic inductance both low, thereby improving the current detection bandwidth.

[0089] Using a PCB board and the signal integration circuit being low-cost components such as resistors, capacitors, and operational amplifiers greatly reduces the cost of the high-bandwidth current detection extraction coil sensor.

[0090] In this embodiment, the power supply port of the voltage follower is grounded.

[0091] In this embodiment, one end of the measurement port V out2 and the power supply port of the operational amplifier are both grounded.

[0092] Figure 7 Schematically shows a schematic diagram of the theoretical analysis of the amplitude-frequency and phase-frequency responses of the single-turn current extraction coil, Figure 8 Schematically shows a schematic diagram of the theoretical analysis of the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor. See Figure 7 and Figure 8As shown, a single-turn current extraction coil is introduced into a finite element parasitic parameter extraction tool, and the parameters of the single-turn current extraction coil are extracted by the finite element parasitic parameter extraction tool. The parameters include parasitic inductance L S , capacitance C s , mutual inductance M s , and resistance R s . The specific parameter values extracted are: the parasitic inductance L S is 9.4 nH, the capacitance C s is 3.5 pF, the resistance R s is 0.338 Ω, and the mutual inductance M s is 0.29 nH. According to the specific parameter values extracted, theoretical analysis is carried out using MATLAB software to obtain the amplitude-frequency response and phase-frequency response of the single-turn current extraction coil. Figure 7 The upper graph in is the theoretical analysis curve of the amplitude-frequency response of the single-turn current extraction coil. The abscissa is the frequency, and the ordinate is the amplitude. Figure 7 The lower graph in is the theoretical analysis curve of the phase-frequency response of the single-turn current extraction coil. The abscissa is the frequency, and the ordinate is the phase. It can be seen that the upper limit bandwidth of the single-turn current extraction coil is as high as 884 MHz. Compared with traditional sensors, the high-bandwidth current detection extraction coil sensor of the present invention has increased the detection bandwidth by 3 times. Refer to Figure 8 As shown, by setting the integration parameters of the passive RC integrator and the active integrator, namely the resistance R0, capacitance C0, capacitance C1, and resistance R2, theoretical analysis is carried out using MATLAB software to obtain the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor. Figure 8 The upper graph in is the theoretical analysis curve of the amplitude-frequency response of the high-bandwidth current detection extraction coil sensor. The abscissa is the frequency, and the ordinate is the amplitude. Figure 8 The lower graph in is the theoretical analysis curve of the phase-frequency response of the high-bandwidth current detection extraction coil sensor. The abscissa is the frequency, and the ordinate is the phase. It can be seen that the amplitude-frequency remains stable in the range of 79 Hz to 884 MHz. Therefore, the high-bandwidth current detection extraction coil sensor of the present invention can achieve current detection with a bandwidth in the ultra-wide range of 79 Hz to 884 MHz.

[0093] Figure 9 Schematically shows a schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency responses of the single-turn current extraction coil. Figure 10 Schematically shows a schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor. On the basis of the above Figure 7 and Figure 8 theoretical analysis, frequency scanning is carried out on the high-bandwidth current detection extraction coil sensor of the present invention using circuit simulation software, and the simulation results are as shown in Figure 9 and Figure 10 . Figure 9The upper graph shows the amplitude-frequency response simulation analysis curve of the single-turn current extraction coil, where the horizontal axis is the frequency and the vertical axis is the amplitude. Figure 9 The lower graph shows the phase-frequency response simulation analysis curve of the single-turn current extraction coil, where the horizontal axis is the frequency and the vertical axis is the phase. Figure 10 The upper graph shows the amplitude-frequency response simulation analysis curve of the high-bandwidth current detection extraction coil sensor, where the horizontal axis is the frequency and the vertical axis is the amplitude. Figure 10 The lower graph shows the phase-frequency response simulation analysis curve of the high-bandwidth current detection extraction coil sensor, where the horizontal axis is the frequency and the vertical axis is the phase. Figure 7 and Figure 8 with Figure 9 and Figure 10 are compared. It can be seen that Figure 7 the amplitude-frequency response and phase-frequency response of the single-turn current extraction coil in the theoretical analysis in Figure 9 are consistent with the amplitude-frequency and phase-frequency responses of the single-turn current extraction coil in the simulation analysis in Figure 8 the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor in the theoretical analysis in Figure 10 are consistent with the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor in the simulation analysis in

[0094] That is, the theoretical analysis and the simulation analysis have the same trends of phase-frequency response curves and amplitude-frequency response curves. Therefore, the high-bandwidth current detection extraction coil sensor of the present invention can achieve current detection in an ultra-wide bandwidth range of 79 Hz to 884 MHz, indicating that the high-bandwidth current detection extraction coil sensor of the present invention can achieve current detection of fast GaN devices. d The high-bandwidth current detection extraction coil sensor according to an embodiment of the present invention includes a single-turn current extraction coil, a coil terminal matching resistor R d and a signal processing circuit; the single-turn current extraction coil is used to generate a voltage according to the input current by using the electromagnetic induction law, and the single-turn current extraction coil includes a single-turn copper coil; the coil terminal matching resistor R d is connected to the single-turn current extraction coil and is used to perform impedance matching on the voltage to generate a matched voltage signal; the signal processing circuit is respectively connected to the single-turn current extraction coil and the coil terminal matching resistor R d and is used to restore the matched voltage signal and output the restored current to achieve current detection. In this way, the single-turn copper coil in the single-turn current extraction coil reduces the parasitic capacitance and parasitic inductance, thereby improving the current detection bandwidth and avoiding the interference of inserted parasitic inductance when measuring the current of fast GaN devices; the single-turn current extraction coil, the coil terminal matching resistor R

[0095] and the signal processing circuit adopted have low prices, making the manufacturing cost of the high-bandwidth current detection extraction coil sensor low.Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified or equivalent substitutions can be made for some technical features without departing from the scope and spirit of the present invention. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way.

[0096] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A high bandwidth current detection extraction coil sensor, characterized in that: It includes a single-turn current extraction coil, a coil terminal matching resistor Rd and a signal processing circuit; The single-turn current extraction coil is used to generate voltage according to the input current by using the law of electromagnetic induction, and the single-turn current extraction coil includes a single-turn copper coil; The coil terminal matching resistor Rd is connected to the single-turn current extraction coil and is used to perform impedance matching on the voltage to generate a matched voltage signal; The signal processing circuit is connected to the single-turn current extraction coil and the coil terminal matching resistor Rd respectively, and is used to restore the matched voltage signal and output the restored current to realize current detection; The single-turn current extraction coil also includes a PCB board and a copper hole, the single-turn copper coil includes a first single-turn copper coil, a second single-turn copper coil, a third single-turn copper coil, a fourth single-turn copper coil, a first connection portion single-turn copper coil, a second connection portion single-turn copper coil, and a third connection portion single-turn copper coil, and the third single-turn copper coil and the fourth single-turn copper coil are both square ring-shaped single-turn coils with openings; Two symmetrically arranged circular openings are provided on the PCB board, and the first single-turn copper coil and the second single-turn copper coil are respectively arranged around the two circular openings; The third single-turn copper coil is arranged on the PCB board, and the third single-turn copper coil is located to the left of the first single-turn copper coil, the lower surface of the first single-turn copper coil and one end of the opening of the third single-turn copper coil are located in the same horizontal plane, and the lower surface of the first single-turn copper coil and one end of the opening of the third single-turn copper coil are connected through the first connecting portion single-turn copper coil; The fourth single-turn copper coil is arranged on the PCB board, and the fourth single-turn copper coil is located to the right of the second single-turn copper coil, the upper surface of the second single-turn copper coil and the open end of the fourth single-turn copper coil are located in the same horizontal plane, the upper surface of the second single-turn copper coil and the open end of the fourth single-turn copper coil are connected through the second connecting portion single-turn copper coil, and the third single-turn copper coil and the fourth single-turn copper coil are symmetrically arranged along the center; The other end of the opening of the third single-turn copper coil and the other end of the opening of the fourth single-turn copper coil are connected through the third connecting portion single-turn copper coil, and the third connecting portion single-turn copper coil is located between the first single-turn copper coil and the second single-turn copper coil; The length of the PCB board is 9 mm, the width of the PCB board is 4.5 mm, the diameters of the two copper holes are both 0.9 mm, and the ring widths of the third single-turn copper coil and the fourth single-turn copper coil are both 0.4 mm.

2. The high bandwidth current detection extraction coil sensor according to claim 1, characterized in that: The high bandwidth current detection extraction coil sensor also includes an output current terminal, a measurement port Vout1 and a measurement port Vout2; The output current terminal is connected to the signal processing circuit and the measurement port Vout2 respectively, and is used to output the restored current; The measurement port Vout1 is connected to the single-turn current extraction coil, the coil terminal matching resistor Rd, and the signal processing circuit respectively, and is used to perform frequency scanning on the single-turn current extraction coil to obtain the bandwidth of the single-turn current extraction coil; The measurement port Vout2 is connected to the signal processing circuit and is used to perform a frequency scan on the high-bandwidth current detection extraction coil sensor to obtain the bandwidth of the high-bandwidth current detection extraction coil sensor.

3. The high bandwidth current detection extraction coil sensor according to claim 2, characterized in that: The signal processing circuit includes a voltage follower, a passive RC integrator, a resistor R1 and an active integrator; The positive input end of the voltage follower is respectively connected to one end of the coil terminal matching resistor Rd, one end of the measuring port Vout1, and the single-turn current extraction coil, the reverse input end of the voltage follower is connected to the passive RC integrator, and the output end of the voltage follower is connected to the passive RC integrator. The voltage follower is used to follow the matched voltage signal and output the followed voltage signal; The passive RC integrator is respectively connected to the other end of the resistor R1, the other end of the coil terminal matching resistor Rd and the other end of the measurement port Vout1, the single-turn current extraction coil, and the active integrator, and is used to filter and integrate the following voltage signal in sequence, and output the integrated current signal; The active integrator is connected to one end of the resistor R1, the measurement port Vout2, and the output current end, respectively, and is used to restore the integrated current signal and output the restored current to achieve current detection; The other end of the resistor R1 is respectively connected to the other end of the measurement port Vout1 , the other end of the coil terminal matching resistor Rd, and the single-turn current extraction coil.

4. The high bandwidth current detection extraction coil sensor according to claim 3, characterized in that: The passive RC integrator includes a resistor R0 and a capacitor C0; One end of the resistor R0 is respectively connected to the output end of the voltage follower and the reverse input end of the voltage follower, the other end of the resistor R0 is connected to one end of the capacitor C0 and the active integrator, one end of the capacitor C0 is connected to the active integrator, and the other end of the capacitor C0 is respectively connected to the other end of the resistor R1, the other end of the coil terminal matching resistor Rd, the other end of the measurement port Vout1, and the single-turn current extraction coil.

5. The high bandwidth current detection extraction coil sensor according to claim 4, characterized in that: The active integrator comprises an operational amplifier, a resistor R2 and a capacitor C1; The positive input terminal of the operational amplifier is respectively connected to the other end of the resistor R0 and one end of the capacitor C0, the reverse input terminal of the operational amplifier is respectively connected to one end of the resistor R1, one end of the resistor R2, and one end of the capacitor C1, the output terminal of the operational amplifier is respectively connected to the other end of the resistor R2, the other end of the capacitor C1, the other end of the measuring port Vout2, and the output current terminal, one end of the resistor R2 is respectively connected to one end of the capacitor C1 and one end of the resistor R1, the other end of the resistor R2 is respectively connected to the other end of the capacitor C1, the output current terminal, and the other end of the measuring port Vout2, one end of the capacitor C1 is connected to one end of the resistor R1, and the other end of the capacitor C1 is connected to the output current terminal and the other end of the measuring port Vout2.

6. The high bandwidth current detection extraction coil sensor according to claim 4, characterized in that: The signal processing circuit also includes a resistor R3; One end of the resistor R3 is connected to the inverting input end of the voltage follower, and the other end of the resistor R3 is connected to the output end of the voltage follower and one end of the resistor R0 respectively.

7. The high bandwidth current detection extraction coil sensor according to claim 5, characterized in that: The equivalent circuit of the single-turn current extraction coil includes the mutual inductance Ms, the resistance Rs, the parasitic inductance LS and the capacitance Cs between the single-turn current extraction coil and the current-carrying conductor to be measured; One end of the mutual inductance Ms is connected to one end of the resistor Rs, and the other end of the mutual inductance Ms is respectively connected to the other end of the capacitor Cs, the other end of the coil terminal matching resistor Rd, the other end of the measurement port Vout1, the other end of the capacitor C0, and the other end of the resistor R1; The other end of the resistor Rs is connected to one end of the parasitic inductance LS, and the other end of the parasitic inductance LS is respectively connected to one end of the capacitor Cs, one end of the coil terminal matching resistor Rd, one end of the measuring port Vout1, and the positive input end of the voltage follower, one end of the capacitor Cs is respectively connected to one end of the coil terminal matching resistor Rd, one end of the measuring port Vout1, and the positive input end of the voltage follower, and the other end of the capacitor Cs is respectively connected to the other end of the coil terminal matching resistor Rd, the other end of the measuring port Vout1, the other end of the capacitor C0, and the other end of the resistor R1.

8. The high bandwidth current detection extraction coil sensor according to claim 3, characterized in that: The power supply port of the voltage follower is grounded.

9. The high bandwidth current detection extraction coil sensor according to claim 5, characterized in that: One end of the measurement port Vout2 and a power supply port of the operational amplifier are both grounded.

10. The high bandwidth current detection extraction coil sensor according to claim 1, characterized in that: The positive output end of the single-turn current extraction coil is connected to the current inflow end of the current-carrying conductor to be measured, and the negative output end of the single-turn current extraction coil is connected to the current output end of the current-carrying conductor to be measured.

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