High-bandwidth current detection extraction coil sensor

Abstract

The invention provides a high-bandwidth current detection extraction coil sensor, and relates to the technical field of current measurement of wide bandgap semiconductor devices. Comprising a single-turn current extraction coil which is used for generating voltage by using the law of electromagnetic induction according to input current, and the single-turn current extraction coil comprises a single-turn copper coil; the coil terminal matching resistor Rd is connected with the single-turn current extraction coil and is used for carrying out impedance matching on the voltage to generate a matched voltage signal; and the signal processing circuit is respectively connected with the single-turn current extraction coil and the coil terminal matching resistor Rd, and is used for restoring the matched voltage signal and outputting the restored current to realize current detection. The single-turn copper coil reduces parasitic capacitance and parasitic inductance, the current detection bandwidth is improved, and parasitic inductance insertion interference is avoided when current measurement is carried out on the rapid GaN device; a single-turn current extraction coil, a coil terminal matching resistor Rd and a signal processing circuit are adopted, so that the manufacturing cost of the high-bandwidth current detection and extraction coil sensor is low.

Description

Technical Field

[0001] The invention relates to the technical field of current measurement of wide bandgap semiconductor devices, and in particular 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. Switching current is a basic parameter for evaluating switching characteristics and verifying GaN devices. However, for fast GaN devices, switching current measurement is a major challenge. Fast GaN devices have very fast switching speeds due to their low capacitance and low parasitic inductance. The edge time t of fast GaN devices is t r It may be less than 1ns. According to the expression of measurement bandwidth BW, It can be seen that at least 350MHz measurement bandwidth is required. In addition, due to the characteristics of fast GaN devices such as fast switching speed, small threshold voltage safety range and parasitic sensitivity, when measuring the current of fast GaN devices, the conditions of having high bandwidth and not introducing too much parasitic inductance in the power converter loop should be met.

[0003] At present, the current detection of fast GaN devices uses Rogowski coil current sensor, which consists of a coil and an integrator; the coil generally adopts a circular spiral structure, and the coil has the advantages of being little 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 the insertion of large parasitic inductance and parasitic capacitance, which limits the measurement bandwidth, resulting in a low bandwidth, and causing the insertion of parasitic inductance interference when measuring the current of fast GaN devices; the commonly used Rogowski coil current sensor model is TRCP0600, which is expensive, making the manufacturing cost of the Rogowski coil current sensor high. Summary of the invention

[0004] The purpose of the embodiment of the present invention is to provide a high-bandwidth current detection extraction coil sensor to solve the problems of low bandwidth of the Rogowski coil current sensor, insertion of parasitic inductance interference when measuring current on a fast GaN device, and 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, comprising a single-turn current extraction coil, a coil terminal matching resistor Rd and signal processing circuits;

[0007] The single-turn current extraction coil is used to generate 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] Coil terminal matching resistance R d , connected to the single-turn current extraction coil, for performing 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 Connection, 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 measurement port V out2 ;

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

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

[0013] Measurement port V out2 , connected to the signal processing circuit, and 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.

[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 matched with the coil terminal matching resistor R d One end and the measurement port V out1 One end of the voltage follower is connected to a single-turn current extraction coil, the reverse input end of the voltage follower is connected to a passive RC integrator, the output end of the voltage follower is connected to a passive RC integrator, and the voltage follower is used to follow the matched voltage signal and output the followed voltage signal;

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

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

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

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

[0020] One end of the resistor R0 is connected to the output end of the voltage follower and the reverse input end of the voltage follower respectively, and 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 connected to the other end of the resistor R1 and the coil terminal matching resistor R d The other end of the measuring port and the single-turn current extraction coil are connected.

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

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

[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 connected to the output end of the voltage follower and one end of the resistor R0 respectively.

[0025] In some embodiments, 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 ;

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

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

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

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

[0030] In some embodiments, 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.

[0031] Compared with the prior art, the present invention provides a high-bandwidth current detection extraction coil sensor, including a single-turn current extraction coil, a coil terminal matching resistor R dand signal processing circuit; a single-turn current extraction coil, used to generate voltage according to the input current using the law of electromagnetic induction, 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, 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 The connection is used to restore the matched voltage signal and output the restored current to realize 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 insertion of parasitic inductance interference when measuring the current of fast GaN devices; the single-turn current extraction coil and the coil terminal matching resistor R d The low price of the signal processing circuit makes the manufacturing cost of the high bandwidth current sensing extraction coil sensor low. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the detailed description below with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0033] Figure 1 The schematic diagram of the structure of the high bandwidth current detection extraction coil sensor is shown schematically;

[0034] Figure 2 Schematic showing the equivalent circuit of a high bandwidth current sensing pick-up coil sensor Figure 1 ;

[0035] Figure 3 Schematic showing the equivalent circuit of a high bandwidth current sensing pick-up coil sensor Figure 2 ;

[0036] Figure 4 The equivalent circuit diagram of a single-turn current extraction coil is schematically shown;

[0037] Figure 5 Schematic showing the equivalent circuit of a high bandwidth current sensing pick-up coil sensor Figure 3 ;

[0038] Figure 6 The structure diagram of a single-turn current extraction coil is schematically shown;

[0039] Figure 7 The schematic diagram of the theoretical analysis of the amplitude-frequency and phase-frequency responses of a single-turn current extraction coil is schematically shown;

[0040] Figure 8 The schematic diagram of the theoretical analysis of the amplitude-frequency and phase-frequency response of the high-bandwidth current detection extraction coil sensor is schematically shown;

[0041] Fig. 9 The schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency response of a single-turn current extraction coil is schematically shown;

[0042] Fig.10 The schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor is shown schematically. DETAILED DESCRIPTION

[0043] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings 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 and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0044] A high-bandwidth current detection extraction coil sensor in an embodiment of the present invention is described in detail below.

[0045] See also Figure 1 As shown, Figure 1 The schematic diagram of the structure of the high-bandwidth current detection extraction coil sensor is shown schematically. The 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 signal processing circuits;

[0046] The single-turn current extraction coil is used to generate 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;

[0047] Coil terminal matching resistance R d , connected to the single-turn current extraction coil, for performing 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 Connection, 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 end 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 end should be connected to the current output end of the current-carrying conductor to be measured, so that the current can be detected by the connected high-bandwidth current detection extraction coil sensor. The high-bandwidth current detection extraction coil sensor is placed on the surface of the current-carrying conductor to be measured, so that the parasitic inductance generated when measuring the current of the current-carrying conductor to be measured is 0, avoiding the interference of the inserted inductance when measuring the current.

[0051] The single-turn current extraction coil uses a single-turn copper coil to reduce 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, which is set according to the basic principle of Faraday's law of electromagnetic induction, and a signal processing circuit is set to process the current through the single-turn current extraction coil and the coil terminal matching resistor R d The generated matched voltage signal is processed to finally obtain the restored current. 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 large current can be directly measured.

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

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

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

[0056] Measurement port V out2 , connected to the signal processing circuit, and 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 Schematic showing the equivalent circuit of a high bandwidth current sensing pick-up 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 matched with the coil terminal matching resistor R d One end and the measurement port V out1 One end of the voltage follower is connected to a single-turn current extraction coil, the reverse input end of the voltage follower is connected to a passive RC integrator, the output end of the voltage follower is connected to a passive RC integrator, and the voltage follower is used to follow the matched voltage signal and output the followed voltage signal;

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

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

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

[0062] The signal processing circuit includes a passive RC integrator and an active integrator. The passive RC integrator and the active integrator enhance the anti-interference performance of the voltage signal and enable ultra-high bandwidth current detection.

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

[0064] The function of the voltage follower is to follow the matched voltage signal to generate a followed voltage signal. The voltage follower has the characteristics of high input impedance and low output impedance. It can isolate the voltage signal, avoid the loss of the voltage signal, and improve the load 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 connected to the output end of the voltage follower and the reverse input end of the voltage follower respectively, and 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 connected to the other end of the resistor R1 and the coil terminal matching resistor R d The other end and the measurement port V out1 The other end of the single-turn current extraction coil is connected.

[0067] Specifically, the following voltage signal passes through the resistor R0 and the capacitor C0 in sequence to be filtered and integrated, and an integrated current signal is output.

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

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

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

[0071] Figure 3 Schematic showing the equivalent circuit of a high bandwidth current sensing pick-up coil sensor Figure 2 , in this embodiment, the signal processing circuit further includes a resistor R3;

[0072] 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.

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

[0074] Figure 4 The equivalent circuit diagram of a single-turn current extraction coil is schematically shown, Figure 5 Schematic showing the equivalent circuit of a high bandwidth current sensing pick-up coil sensor 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] Mutual Inductance s One end of the resistor R s One end is connected, the mutual inductance M s The other end of the capacitor C s The other end of the coil terminal matching resistor R d The other end, measurement port V out1 The other end of the capacitor C0 and the other end of the resistor R1 are connected;

[0076] Resistor R s The other end of the parasitic inductance L S One end is connected to the parasitic inductance L S The other end of the capacitor C s One end of the coil terminal matching resistor R d One end of the measuring port V out1 One end of the voltage follower is connected to the positive input terminal, and the capacitor C s One end of the coil terminal matching resistor R d One end of the measuring port V out1 One end of the voltage follower is connected to the positive input terminal, and the capacitor C s The other end is matched with the coil terminal matching resistor R d The other end, measurement port V out1 The other end of , the other end of capacitor C0, and the other end of resistor R1 are connected.

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

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

[0079] according to Calculate the upper bandwidth f of the single-turn current extraction coil H , usually R d >>R s , the expression of the upper bandwidth of the above single-turn current extraction coil can be simplified to: The finite element parasitic parameter extraction tool is used to extract the parameters of the single-turn current extraction coil, which includes the parasitic inductance L S and capacitor C s The expression of the upper bandwidth of the coil is extracted by simplifying the single-turn current, and the parasitic inductance and capacitance C are extracted. s The upper bandwidth of the single-turn current extraction coil is calculated based on the parameters. The lower bandwidth f of the single-turn current extraction coil can be obtained L By adjusting R0C0=R1C1, the passive integrator and the active integrator can transition smoothly.

[0080] Figure 6 The structure diagram of a 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 board (PCB) 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. The third single-turn copper coil and the fourth single-turn copper coil are both square ring-shaped single-turn coils with openings.

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

[0083] The fourth single-turn copper coil is arranged 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 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;

[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 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.

[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 terminal of the single-turn current extraction coil, namely in+, to the negative input terminal, namely in-, and a voltage is generated at both ends of the single-turn current extraction coil, namely out+ and out-.

[0087] The single-turn current extraction coil uses a single-turn copper coil setup to achieve up to 884MHz bandwidth.

[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 loop width is 0.4 mm, and the size of the entire single-turn current extraction coil is small, which makes the single-turn current extraction coil easy to install, and makes the parasitic capacitance and parasitic inductance both low, thereby improving the current detection bandwidth.

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

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

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

[0092] Figure 7 The schematic diagram of the theoretical analysis of the amplitude-frequency and phase-frequency response of a single-turn current extraction coil is shown schematically. Figure 8 The schematic diagram shows the theoretical analysis of the amplitude-frequency and phase-frequency response of the high-bandwidth current detection extraction coil sensor, see Figure 7 and Figure 8As shown, the single-turn current extraction coil is imported into the finite element parasitic parameter extraction tool, and the parameters of the single-turn current extraction coil are extracted using the finite element parasitic parameter extraction tool. The parameters include the parasitic inductance L S , capacitor C s 、M s And the resistor R s The specific parameter values ​​extracted are: parasitic inductance L S is 9.4 nanohenries, the capacitance C s is 3.5 pF, the resistance R s is 0.338 ohms, mutual inductance M s The amplitude-frequency response and phase-frequency response of the single-turn current extraction coil are obtained by theoretical analysis using MATLAB software according to the specific parameter values ​​extracted. Figure 7 The figure above is the theoretical analysis curve of the amplitude-frequency response of a single-turn current extraction coil. The horizontal axis is the frequency and the vertical axis is the amplitude. Figure 7 The figure below is the phase-frequency response theoretical analysis curve of the single-turn current extraction coil, with the horizontal axis being the frequency and the vertical axis being the phase. It can be seen that the upper bandwidth of the single-turn current extraction coil is as high as 884MHz. Compared with the traditional sensor, the high-bandwidth current detection extraction coil sensor of the present invention increases the detection bandwidth by 3 times. Figure 8 As shown, by setting the integration parameters of the passive RC integrator and the active integrator, namely the resistor R0, the capacitor C0, the capacitor C1 and the resistor R2, the MATLAB software is used for theoretical analysis to obtain the amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor. Figure 8 The figure above is the theoretical analysis curve of the amplitude-frequency response of the high-bandwidth current detection extraction coil sensor. The horizontal axis is the frequency and the vertical axis is the amplitude. Figure 8 The figure below is a phase-frequency response theoretical analysis curve of the high-bandwidth current detection extraction coil sensor, with the horizontal axis being the frequency and the vertical axis being the phase. It can be seen that the amplitude-frequency remains stable within the range of 79Hz to 884MHz, so the high-bandwidth current detection extraction coil sensor of the present invention can realize current detection within the ultra-wide bandwidth range of 79Hz to 884MHz.

[0093] Fig. 9 The schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency response of a single-turn current extraction coil is shown schematically. Fig.10 The schematic diagram of the simulation analysis of the amplitude-frequency and phase-frequency response of the high-bandwidth current detection extraction coil sensor is shown schematically. Figure 7 and Figure 8 Based on the theoretical analysis, the high bandwidth current detection extraction coil sensor of the present invention is frequency scanned using circuit simulation software. The simulation results are as follows: Fig. 9 and Fig.10 shown. Fig. 9The figure above is the amplitude-frequency response simulation analysis curve of a single-turn current extraction coil. The horizontal axis is the frequency and the vertical axis is the amplitude. Fig. 9 The figure below is the phase-frequency response simulation analysis curve of the single-turn current extraction coil, with the horizontal axis being the frequency and the vertical axis being the phase; Fig.10 The figure above is the amplitude-frequency response simulation curve of the high-bandwidth current detection extraction coil sensor. The horizontal axis is the frequency and the vertical axis is the amplitude. Fig.10 The figure below is the phase-frequency response simulation analysis curve of the high-bandwidth current detection extraction coil sensor, with the horizontal axis being the frequency and the vertical axis being the phase. Figure 7 and Figure 8 and Fig. 9 and Fig.10 By comparison, it can be seen that Figure 7 The amplitude-frequency response and phase-frequency response of the single-turn current extraction coil are theoretically analyzed in Fig. 9 The amplitude-frequency and phase-frequency responses of the single-turn current extraction coil in the simulation analysis are consistent. Figure 8 Theoretical analysis of the high bandwidth current detection extraction coil sensor amplitude frequency and phase frequency response, and Fig.10 The amplitude-frequency and phase-frequency responses of the high-bandwidth current detection extraction coil sensor in the simulation analysis are consistent, that is, the theoretical analysis and the simulation analysis have the same phase-frequency response curve trend and amplitude-frequency response curve trend. Therefore, the high-bandwidth current detection extraction coil sensor of the present invention can realize current detection with a bandwidth in an ultra-wide range of 79Hz to 884MHz, which shows that the high-bandwidth current detection extraction coil sensor of the present invention can realize current detection of fast GaN devices.

[0094] The high-bandwidth current detection extraction coil sensor of the embodiment of the present invention comprises a single-turn current extraction coil, a coil terminal matching resistor R d and signal processing circuit; a single-turn current extraction coil, used to generate voltage according to the input current using the law of electromagnetic induction, 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, 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 The connection is used to restore the matched voltage signal and output the restored current to realize 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 insertion of parasitic inductance interference when measuring the current of fast GaN devices; the single-turn current extraction coil and the coil terminal matching resistor R d The low price of the signal processing circuit makes the manufacturing cost of the high bandwidth current sensing extraction coil sensor low.

[0095] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict.

[0096] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on 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.

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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