Current phase correction circuit and current sensor

Abstract

The invention relates to a current phase correction circuit and a current sensor. The current phase correction circuit comprises a first current port, a second current port, a phase detection circuit and a phase adjustment circuit. The input end of the phase detection circuit is connected with the second current port, and the output end of the phase detection circuit is connected with the first input end of the phase adjustment circuit; the second input end of the phase adjusting circuit is connected with the second current port, and the output end of the phase adjusting circuit is connected with the first current port; the phase detection circuit is used for outputting a control signal according to the phase difference between the input current and the standard current; and the phase adjustment circuit comprises an adjustable passive device and is used for adjusting the value of the adjustable passive device according to the control signal so as to realize current phase adjustment and outputting the adjusted current through the first current port. According to the invention, the accuracy of current measurement can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of current measurement, and in particular to a current phase correction circuit and a current sensor. Background Art

[0002] Current sensors are commonly used in power transmission networks. They typically measure transmission line current by sensing the current to be measured using a probe. This sensed current is then fed into an operational amplifier (such as an integrator) for processing, resulting in the measured current. However, this resulting measured current often exhibits phase shifts, leading to inaccurate corrections. Summary of the Invention

[0003] Based on this, it is necessary to provide a current phase correction circuit and a current sensor to improve the accuracy of the correction current.

[0004] In a first aspect, the present application provides a current phase correction circuit. The current phase correction circuit includes a first current port, a second current port, a phase detection circuit, and a phase adjustment circuit; the input end of the phase detection circuit is connected to the second current port, and the output end of the phase detection circuit is connected to the first input end of the phase adjustment circuit; the second input end of the phase adjustment circuit is connected to the second current port, and the output end of the phase adjustment circuit is connected to the first current port;

[0005] a phase detection circuit for outputting a control signal according to a phase difference between an input current and a standard current;

[0006] The phase adjustment circuit includes an adjustable passive device, which is used to adjust the numerical value of the adjustable passive device according to a control signal to achieve current phase adjustment, and output the adjusted current through the first current port; wherein the phase difference between the adjusted current and the standard current is within a preset range.

[0007] In one embodiment, the first current port is connected to a first input terminal of an amplifier outside the circuit, and the second current port is connected to an output terminal of the amplifier;

[0008] The amplifier is used to amplify the induced current or the adjusted current and transmit it to the phase adjustment circuit.

[0009] In one embodiment, the phase detection circuit includes a phase detector; an input end of the phase detector is connected to an output end of the amplifier, and an output end of the phase detector is connected to a first input end of the phase adjustment circuit;

[0010] The phase detector is used to detect the phase difference between the current output by the amplifier and the standard current, and output a control signal according to the phase difference.

[0011] In one embodiment, the phase adjustment circuit includes an RC network, a first end of the RC network is connected to the output end of the phase detector, a second end of the RC network is connected to the first input end of the amplifier, and a third end of the RC network is connected to the output end and the second current port of the amplifier respectively;

[0012] The RC network is used to adjust device parameters according to a control signal output by the phase detector, and to adjust the current phase based on the adjusted device parameters to obtain an adjusted current.

[0013] In one embodiment, the RC network includes a first adjustable capacitor and a first resistor;

[0014] A first end of the first adjustable capacitor is connected to the output end of the phase detector, a second end of the first adjustable capacitor is connected to the first input end of the amplifier, and a third end of the first adjustable capacitor is connected to the first end of the resistor;

[0015] The second end of the resistor is connected to the second current port and the input end of the phase detector respectively.

[0016] In one embodiment, the RC network includes a second adjustable capacitor and a second resistor;

[0017] A first end of the second adjustable capacitor is connected to the output end of the phase detector, a second end of the second adjustable capacitor is connected to the first input end of the amplifier, and a third end of the second adjustable capacitor is connected to the second current port and the input end of the phase detector respectively;

[0018] The first end of the second resistor is connected to the second end of the second adjustable capacitor, and the second end of the second resistor is connected to the third end of the second adjustable capacitor.

[0019] In one embodiment, the phase adjustment circuit includes an LC network, a first end of the LC network is connected to the output end of the phase detector, a second end of the LC network is connected to the first input end of the amplifier, and a third end of the LC network is connected to the output end and the second current port of the amplifier respectively.

[0020] In one embodiment, the current phase correction circuit further includes a filter circuit, wherein an input end of the filter circuit is connected to an output end of the phase detector, and an output end of the filter circuit is connected to a first end of the adjustable passive device;

[0021] The filter circuit is used to filter the control signal and transmit the filtered control signal to the adjustable passive device.

[0022] In a second aspect, an embodiment of the present application provides a current sensor, which includes a detection probe, an amplifier, and a current phase correction circuit as described in any one of the first aspects.

[0023] In one embodiment, the detection probe includes an induction coil and an integrator connected to each other, and the integrator is connected to a first current port of the current phase correction and a first input terminal of the amplifier.

[0024] In the above-mentioned current phase correction circuit and current sensor, the current phase correction circuit includes a first current port, a second current port, a phase detection circuit, and a phase adjustment circuit. The current to be corrected is input into the phase detection circuit, which determines the phase difference between the current and the standard current and outputs a control signal based on the phase difference; the phase adjustment circuit adjusts the current phase according to the control signal and feeds the adjusted current back to the phase detection circuit, which detects the phase difference between the adjusted current and the standard current. Through a closed-loop feedback mechanism, the phase difference between the current adjusted by the phase adjustment circuit and the standard current is gradually reduced to within a preset range. In the embodiment of the present application, the phase detection circuit and the phase adjustment circuit can correct the phase offset of the current, obtain a measured current with accurate phase, and improve the accuracy of current measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the structure of a current phase correction circuit in one embodiment;

[0027] Figure 2 This is a second structural diagram of a current phase correction circuit in one embodiment;

[0028] Figure 3 This is a third structural diagram of a current phase correction circuit in one embodiment;

[0029] Figure 4 This is a fourth structural diagram of a current phase correction circuit in one embodiment;

[0030] Figure 5 This is a fifth structural diagram of a current phase correction circuit in one embodiment;

[0031] Figure 6 This is a sixth structural diagram of a current phase correction circuit in one embodiment;

[0032] Figure 7 This is a seventh structural diagram of a current phase correction circuit in one embodiment;

[0033] Figure 8 This is an eighth structural diagram of a current phase correction circuit in one embodiment;

[0034] Figure 9 This is a schematic diagram of the structure of a current sensor in one embodiment;

[0035] Figure 10 This is a second structural diagram of a current sensor in one embodiment.

[0036] Description of reference numerals:

[0037] I1, first current port; I2, second current port; 10, current phase correction circuit;

[0038] 11. Phase detection circuit; 12. Phase adjustment circuit; 111. Phase detector; 20. Amplifier;

[0039] 121, RC network; 122, LC network; C1, first adjustable capacitor; R1, first resistor;

[0040] C2, second adjustable capacitor; R2, second resistor; 13, filter circuit;

[0041] 30. Detection probe; 301. Induction coil; 302. Integrator. DETAILED DESCRIPTION

[0042] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0044] It will be understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor without departing from the scope of this application. The first resistor and the second resistor are both resistors, but they are not the same resistor.

[0045] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if there is transmission of electrical signals or data between the connected circuits, modules, units, etc.

[0046] It is understood that “at least one” refers to one or more, “a plurality” refers to two or more, and “at least a portion of an element” refers to a portion or all of an element.

[0047] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include," "comprising," "having," and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Furthermore, the term "and / or" as used in this specification includes any and all combinations of the relevant listed items.

[0048] Before specifically introducing the technical solutions of the embodiments of this application, we will first introduce the technical background and technological evolution of the embodiments of this application. Current sensors are commonly used in power transmission networks. Current measurement methods for transmission line current typically involve sensing the current to be measured using a detection probe. This induced current is then fed into an operational amplifier (such as an integrator) for processing to obtain the measured current. However, the resulting measured current often exhibits phase shifts, resulting in inaccurate current measurements.

[0049] Currently, a common calibration method involves phase adjustment of the resistor, capacitor, or inductor network structure and size, and observation using an oscilloscope. However, this method relies on manual labor and suffers from limited calibration flexibility. Another common calibration method involves phase adjustment of the measured signal in the digital domain based on algorithm-driven or other hybrid calibration methods. However, this method relies on complex processing algorithms and high-cost digital components.

[0050] In response to the above-mentioned problems, an embodiment of the present application provides a current phase correction circuit, which includes a first current port, a second current port, a phase detection circuit, and a phase adjustment circuit. The induced current of the current to be corrected is input into the phase detection circuit, which determines the phase difference between the current and the standard current and outputs a control signal according to the phase difference; the phase adjustment circuit adjusts the current phase according to the control signal and feeds the adjusted current back to the phase detection circuit, which detects the phase difference between the adjusted current and the standard current. Through a closed-loop feedback mechanism, the phase difference between the current adjusted by the phase adjustment circuit and the standard current is gradually reduced to within a preset range. The embodiment of the present application can correct the phase offset of the current through the phase detection circuit and the phase adjustment circuit, obtain a measured current with accurate phase, and improve the accuracy of current measurement.

[0051] According to some embodiments of the present application, Figure 1 As shown, a current phase correction circuit 10 includes a first current port I1, a second current port I2, a phase detection circuit 11, and a phase adjustment circuit 12. The input end of the phase detection circuit 11 is connected to the second current port I2, and the output end of the phase detection circuit 11 is connected to the first input end of the phase adjustment circuit 12. The second input end of the phase adjustment circuit 12 is connected to the second current port I2, and the output end of the phase adjustment circuit 12 is connected to the first current port I1. The phase detection circuit 11 is configured to output a control signal based on the phase difference between the input current and the standard current. The phase adjustment circuit 12 includes an adjustable passive device, configured to adjust the value of the adjustable passive device according to the control signal to achieve current phase adjustment, and output the adjusted current through the first current port I1. The phase difference between the adjusted current and the standard current is within a preset range.

[0052] In the embodiment of the present application, the current phase correction circuit includes a first current port I1, a second current port I2, a phase detection circuit 11, and a phase adjustment circuit 12. The second current port I2 is connected to the input of the phase detection circuit 11, and the output of the phase detection circuit 11 is connected to the first input of the phase adjustment circuit 12. The second input of the phase adjustment circuit 12 is connected to the second current port I2, and the output of the phase adjustment circuit 12 is connected to the first current port I1.

[0053] The detection probe senses the current to be measured to obtain an induced current. The induced current is processed to have a phase shift, and the phase-shifted current is input into the phase detection circuit 11 through the second current port I2.

[0054] The phase of the standard current can be pre-set in the phase detection circuit 11, or an external standard power supply can be connected to receive the standard current transmitted by the standard power supply. After receiving the input current, the phase detection circuit 11 compares the phase of the input current with the phase of the standard current to obtain the phase difference between the input current and the standard current. Thereafter, the phase detection circuit 11 generates a control signal based on the phase difference. In some embodiments, the control signal includes a control voltage, and the magnitude of the control voltage is positively correlated with the phase difference, that is, the larger the phase difference, the larger the control voltage; the smaller the phase difference, the smaller the control voltage. In other embodiments, the control signal includes a control current, and the magnitude of the control current is positively correlated with the phase difference, that is, the larger the phase difference, the larger the control current; the smaller the phase difference, the smaller the control current.

[0055] The control signal generated by the phase detection circuit 11 is input to the phase adjustment circuit 12. The phase adjustment circuit 12 adjusts the phase of the phase-shifted current according to the control signal and outputs the adjusted current through the first current port I1. The adjusted current is re-input into the phase detection circuit 11 through the second current port I2. The phase detection circuit 11 compares the phase of the adjusted current with the phase of the standard current to obtain a new phase difference, and generates a new control signal based on the new phase difference. The new control signal is input to the phase adjustment circuit 12. The phase adjustment circuit 12 adjusts the phase of the last adjusted current according to the new control signal. Similarly, through the closed-loop feedback mechanism, the phase adjustment circuit 12 performs at least one phase adjustment until the phase difference between the adjusted current and the standard current gradually decreases to within a preset range. The adjusted current is output through the first current port I1.

[0056] In the above embodiment, the current phase correction circuit includes a first current port, a second current port, a phase detection circuit, and a phase adjustment circuit. The current to be corrected is input into the phase detection circuit, which determines the phase difference between the current and the standard current and outputs a control signal based on the phase difference. The phase adjustment circuit adjusts the current phase based on the control signal and feeds the adjusted current back to the phase detection circuit, which detects the phase difference between the adjusted current and the standard current. Through a closed-loop feedback mechanism, the phase difference between the current adjusted by the phase adjustment circuit and the standard current is gradually reduced to within a preset range. In the embodiment of the present application, the phase detection circuit and the phase adjustment circuit can correct the phase offset of the current to obtain a measured current with accurate phase, thereby improving the accuracy of the current measurement. In addition, the measurement method of the embodiment of the present application does not rely on manual labor or complex processing algorithms, which not only improves calibration flexibility but also has a relatively low implementation cost.

[0057] According to some embodiments of the present application, Figure 2As shown, the first current port I1 is connected to the first input terminal of the amplifier 20 outside the circuit, and the second current port I2 is connected to the output terminal of the amplifier 20; the amplifier 20 is used to amplify the induced current or the adjusted current and transmit it to the phase adjustment circuit.

[0058] In the embodiment of the present application, the detection probe can sense the current to be measured to obtain an induced current. This induced current is transmitted to the first input terminal of the amplifier 20, which amplifies the induced current and transmits it to the phase detection circuit 11. It should be noted that the amplifier 20 can transmit the amplified induced current to the phase detection circuit 11 according to a preset proportionality factor.

[0059] Phase detection circuit 11 compares the phase of the amplifier output current with the phase of the reference current to determine the phase difference between the two. Phase detection circuit 11 then generates a control signal based on the phase difference and inputs the generated control signal to phase adjustment circuit 12. Phase adjustment circuit 12 adjusts the phase of the amplifier output current based on the control signal and outputs the adjusted current through first current port I1. The adjusted current is input to amplifier 20, which amplifies the adjusted current and outputs it to phase detection circuit 11.

[0060] Phase detection circuit 11 compares the phase of the adjusted current with the phase of the standard current to obtain a new phase difference, and generates a new control signal based on the new phase difference. The new control signal is input to phase adjustment circuit 12, which adjusts the phase of the previously adjusted current based on the new control signal.

[0061] Similarly, through the closed-loop feedback mechanism, the phase adjustment circuit 12 performs at least one phase adjustment until the phase difference between the adjusted current and the standard current gradually decreases to within a preset range. Finally, the measured current is output through the second current port I2.

[0062] In the above embodiment, the first current port is connected to the output of an amplifier external to the circuit, and the second current port is connected to the first input of the amplifier; the amplifier amplifies the induced current or the adjusted current and transmits it to the phase adjustment circuit. In the embodiment of the present application, the phase adjustment circuit and the amplifier form a closed-loop control loop, which can achieve closed-loop current correction and obtain a more accurate correction current.

[0063] According to some embodiments of the present application, Figure 3As shown, the phase detection circuit 11 includes a phase detector 111; the input end of the phase detector 111 is connected to the output end of the amplifier 20, and the output end of the phase detector 111 is connected to the first input end of the phase adjustment circuit 12; the phase detector 111 is used to detect the phase difference between the current output by the amplifier and the standard current, and output a control signal according to the phase difference.

[0064] In the embodiment of the present application, the phase detection circuit 11 includes a phase detector 111 , an input end of the phase detector 111 is connected to the output end of the amplifier 20 , and an output end of the phase detector 111 is connected to the first input end of the phase adjustment circuit 12 .

[0065] The detection probe senses the current to be measured, generating an induced current. This induced current is transmitted to the first input terminal of amplifier 20, which amplifies the induced current and transmits it to phase detection circuit 11. After receiving the current output by the amplifier, phase detector 111 detects the phase difference between the current and the standard current and generates a control signal based on the phase difference. Phase detector 111 then transmits the control signal to phase adjustment circuit 12. Phase adjustment circuit 12 adjusts the value of the adjustable passive component based on the control signal to achieve phase adjustment of the current output by the amplifier, and transmits the adjusted current to amplifier 20 through first current port I1.

[0066] Amplifier 20 transmits the adjusted current to phase adjustment circuit 12 and phase detector 111. Phase detector 111 receives the adjusted current, detects the phase difference between the adjusted current and the standard current, and generates a new control signal based on the new phase difference. Phase detector 111 then transmits the new control signal to phase adjustment circuit 12. Phase adjustment circuit 12 receives the adjusted current and the new control signal, adjusts the value of the adjustable passive component based on the new control signal, and achieves phase adjustment of the adjusted current. It then transmits the adjusted current to amplifier 20.

[0067] Similarly, through the closed-loop feedback mechanism, the phase adjustment circuit 12 performs at least one phase adjustment until the phase difference between the adjusted current and the standard current gradually decreases to within a preset range.

[0068] In some embodiments, phase detector 111 detects the phase difference between two input signals by performing specific processing on them. This detection method can be based on either an analog multiplier or a digital logic circuit. Phase detector 111 based on an analog multiplier multiplies the two input signals and then filters out high-frequency components using a low-pass filter. The resulting DC component is proportional to the phase difference between the two signals. Phase detector 111 based on a digital logic circuit uses a counter and a clock signal to measure the phase difference between the two signals.

[0069] It should be noted that the structure of the phase detector 111 is not limited to the above example, and in practical applications, other structures may also be adopted.

[0070] In the above-mentioned embodiment, the phase detection circuit includes a phase detector; the phase detector detects the phase difference between the current output by the amplifier and the standard current and outputs a control signal based on the phase difference. In the present embodiment, the phase detector determines the phase difference between the current output by the amplifier and the standard current, facilitating subsequent phase correction, thereby reducing current phase offset and improving current measurement accuracy.

[0071] According to some embodiments of the present application, Figure 4 As shown, the phase adjustment circuit 12 includes an RC network 121. A first end of the RC network 121 is connected to the output end of the phase detector 111, a second end of the RC network 121 is connected to the first input end of the amplifier 20, and a third end of the RC network 121 is connected to the output end and the second current port I2 of the amplifier 20 respectively. The RC network 121 is used to adjust device parameters according to the control signal output by the phase detector 111, and perform current phase adjustment based on the adjusted device parameters to obtain an adjusted current.

[0072] In an embodiment of the present application, the phase adjustment circuit 12 includes an RC network 121, which includes an adjustable passive device. The first end of the RC network 121 is connected to the output end of the phase detector 111, the second end of the RC network 121 is connected to the first input end of the amplifier 20, and the third end of the RC network 121 is respectively connected to the output end and the second current port I2 of the amplifier 20.

[0073] In the first phase, phase detector 111 outputs a control signal based on the phase difference between the input current and the reference current. This control signal is transmitted to the first terminal of RC network 121, which then adjusts the device parameters based on the control signal. As the device parameters are adjusted, the phase of the current passing through RC network 121 changes, achieving the effect of current phase adjustment.

[0074] In the second phase, phase detector 111 outputs a new control signal based on the phase difference between the adjusted current and the standard current. This new control signal is transmitted to the first end of RC network 121, which then adjusts the device parameters again based on the new control signal. Due to the adjustment of the device parameters, the phase of the adjusted current passing through RC network 121 changes, achieving a phase adjustment effect on the adjusted current.

[0075] The adjustment process of the second stage is repeated subsequently. During each adjustment process, the device parameters of the RC network 121 are adjusted according to the control signal until the phase difference between the adjusted current and the standard current is within a preset range.

[0076] In the above embodiment, the phase adjustment circuit includes an RC network. The embodiment of the present application uses the RC network to perform phase adjustment, has a simple circuit structure, does not rely on complex processing algorithms, and has a relatively low implementation cost.

[0077] According to some embodiments of the present application, Figure 5 As shown, the RC network 121 includes a first adjustable capacitor C1 and a first resistor R1; a first end of the first adjustable capacitor C1 is connected to the output end of the phase detector 111, a second end of the first adjustable capacitor C1 is connected to the second input end of the amplifier 20, and a third end of the first adjustable capacitor C1 is connected to the first end of the first resistor R1; a second end of the first resistor R1 is connected to the second current port I2 and the output end of the amplifier 20, respectively.

[0078] In the embodiment of the present application, the parameter adjustable device 201 uses a first adjustable capacitor C1, and the phase adjustment circuit 12 also includes a first resistor R1. The first adjustable capacitor C1 and the first resistor R1 form an RC network. The first end of the first adjustable capacitor C1 is connected to the output end of the phase detector 111, the second end of the first adjustable capacitor C1 is connected to the first input end of the amplifier 20, and the third end of the first adjustable capacitor C1 is connected to the first end of the first resistor R1; the second end of the first resistor R1 is respectively connected to the second current port I2 and the output end of the amplifier 20.

[0079] In the first stage, the phase detector 111 outputs a control signal based on the phase difference between the input current and the standard current. The control signal is transmitted to the first terminal of the first adjustable capacitor C1. The first adjustable capacitor C1 adjusts the capacitance parameters according to the control signal, such as adjusting the capacitance value, adjusting the distance between the capacitor plates, adjusting the dielectric constant of the capacitor, etc. As the capacitance parameters are adjusted, the phase of the current passing through the first adjustable capacitor C1 changes, achieving the effect of phase adjustment of the current.

[0080] In the second phase, the phase detector 111 outputs a new control signal based on the phase difference between the adjusted current and the standard current. The new control signal is transmitted to the first terminal of the first adjustable capacitor C1, and the first adjustable capacitor C1 adjusts its capacitance parameters again based on the new control signal. Due to the adjustment of the capacitance parameters, the phase of the adjusted current passing through the first adjustable capacitor C1 changes, achieving the effect of phase adjustment of the adjusted current.

[0081] The second stage adjustment process is then repeated. During each adjustment process, the capacitance parameter of the first adjustable capacitor C1 is adjusted according to the control signal until the phase difference between the adjusted current and the standard current is within a preset range. The phase adjustment circuit 12 outputs the correction current through the first current port I1. The amplifier 20 outputs the measurement current through the second current port I2 according to the correction circuit.

[0082] In some embodiments, the first adjustable capacitor C1 may be a GaN or AlGaN variable capacitor.

[0083] In the above embodiment, the parameter adjustable device includes a first adjustable capacitor and a first resistor. The embodiment of the present application constructs a phase adjustment circuit through an RC network. The circuit structure is simple and does not rely on complex processing algorithms, so the implementation cost is relatively low.

[0084] According to some embodiments of the present application, Figure 6 As shown, the RC network includes a second adjustable capacitor C2 and a second resistor R2; a first end of the second adjustable capacitor C2 is connected to the output end of the phase detector 111, a second end of the second adjustable capacitor C2 is connected to the first input end of the amplifier 20, and a third end of the second adjustable capacitor C2 is connected to the second current port I2 and the input end of the phase detector 111 respectively; a first end of the second resistor R2 is connected to the second end of the second adjustable capacitor C2, and a second end of the second resistor R2 is connected to the third end of the second adjustable capacitor C2.

[0085] In the embodiment of the present application, the RC network may further include a second adjustable capacitor C2 and a second resistor R2 connected in parallel. By constructing a phase adjustment circuit through the RC network, the circuit structure is simple, and does not rely on complex processing algorithms, so the implementation cost is relatively low.

[0086] According to some embodiments of the present application, Figure 7 As shown, the phase adjustment circuit 12 includes an LC network 122, a first end of the LC network 122 is connected to the output end of the phase detector 111, a second end of the LC network 122 is connected to the first input end of the amplifier 20, and a third end of the LC network 122 is connected to the output end and the second current port of the amplifier 20 respectively.

[0087] In the embodiment of the present application, the resistor in the RC network can be replaced with an inductor to obtain an LC network. The phase adjustment circuit constructed by the LC network has a simple circuit structure and does not rely on complex processing algorithms, resulting in a relatively low implementation cost.

[0088] According to some embodiments of the present application, Figure 8 As shown, the current phase correction circuit also includes a filter circuit 13, the input end of the filter circuit 13 is connected to the output end of the phase detector 111, and the output end of the filter circuit 13 is connected to the first end of the adjustable passive device; the filter circuit 13 is used to filter the control signal and transmit the filtered control signal to the adjustable passive device.

[0089] In the embodiment of the present application, the current phase correction circuit further includes a filter circuit 13, which is disposed between the phase detector 111 and the adjustable passive component. For example, if the adjustable passive component is the first adjustable capacitor C1, the input end of the filter circuit 13 is connected to the output end of the phase detector 111, and the output end of the filter circuit 13 is connected to the first end of the first adjustable capacitor C1.

[0090] The control signal output by phase detector 111 is transmitted to filter circuit 13, which performs spurious filtering and signal smoothing on the control signal. Filter circuit 13 then transmits the processed control signal to the first terminal of first adjustable capacitor C1. First adjustable capacitor C1 adjusts its capacitance parameters based on the processed control signal, thereby adjusting the current phase.

[0091] In the above-described embodiment, the current phase correction circuit further includes a filtering circuit that filters the control signal and transmits the filtered control signal to the adjustable passive device. The present embodiment of the present application reduces interference and improves the accuracy of the control signal by processing the control signal through the filtering circuit, thereby improving the parameter adjustment accuracy of the adjustable passive device, thereby improving the accuracy of current adjustment and reducing the phase offset of the correction current.

[0092] According to some embodiments of the present application, Figure 9 As shown, a current sensor is provided, which includes a detection probe 30, an amplifier 20 and a current phase correction circuit 10 according to any one of the above embodiments.

[0093] In this embodiment of the present application, the current sensor includes a detection probe 30, an amplifier 20, and a current phase correction circuit 10. The detection probe 30 is connected to a first input terminal of the amplifier 20. The detection probe 40 senses the current to be measured and transmits the resulting induced current to the amplifier 20. The amplifier 20 amplifies the induced current and transmits it to the current phase correction circuit 10. The current phase correction circuit 10 adjusts the phase of the amplified induced current and ultimately outputs a measured current with an accurate phase.

[0094] In the above embodiment, the current sensor includes a detection probe, an amplifier, and a current phase correction circuit. In the embodiment of the present application, the current phase correction circuit adjusts the phase of the phase-shifted current to obtain a measured current with accurate phase, thereby improving the accuracy of current measurement.

[0095] According to some embodiments of the present application, Figure 10 As shown, the detection probe 30 includes an induction coil 301 and an integrator 302 connected to each other. The integrator 302 is connected to the first current port I1 of the current phase correction circuit 10 and the first input terminal of the amplifier 20 .

[0096] In the embodiment of the present application, the detection probe 30 includes an induction coil 301 and an integrator 302. The induction coil 301 senses the current to be measured and transmits the obtained induced voltage to the integrator 302; the integrator 302 integrates the induced voltage to obtain the induced current and transmits the induced current to the amplifier 20.

[0097] In some embodiments, the induction coil 301 can be a Rogowski coil. A Rogowski coil, also known as a Rogowski coil or hollow coil, is a contactless AC current sensor based on the principle of electromagnetic induction. Its core feature is its hollow ring structure, enabling flexible measurement. It is particularly suitable for high-frequency, high-current scenarios.

[0098] In some embodiments, a Hall sensor, a current transformer or an optical fiber sensor may be used to sense the current to be measured. The embodiment of the present application does not limit the sensing method and may be set according to actual conditions.

[0099] In the above embodiment, the detection probe includes an induction coil and an integrator connected to each other. In the embodiment of the present application, the induction coil and the integrator are used to obtain the induced current, thereby measuring and correcting the induced current to obtain a corrected current with accurate phase, thereby improving the accuracy of the current measurement.

[0100] In the description of this specification, reference to the terms "some embodiments" or "other embodiments" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0101] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0102] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A current phase correction circuit, characterized in that: The current phase correction circuit includes a first current port, a second current port, a phase detection circuit, and a phase adjustment circuit; the input end of the phase detection circuit is connected to the second current port, and the output end of the phase detection circuit is connected to the first input end of the phase adjustment circuit; the second input end of the phase adjustment circuit is connected to the second current port, and the output end of the phase adjustment circuit is connected to the first current port; The phase detection circuit is used to output a control signal according to the phase difference between the input current and the standard current; The phase adjustment circuit includes an adjustable passive device, which is used to adjust the numerical value of the adjustable passive device according to the control signal to achieve current phase adjustment, and output the adjusted current through the first current port; wherein the phase difference between the adjusted current and the standard current is within a preset range.

2. The current phase correction circuit according to claim 1, wherein: The first current port is connected to a first input terminal of an amplifier outside the circuit, and the second current port is connected to an output terminal of the amplifier; The amplifier is used to amplify the induced current or the adjusted current and transmit it to the phase adjustment circuit.

3. The current phase correction circuit according to claim 2, characterized in that: The phase detection circuit includes a phase detector; the input end of the phase detector is connected to the output end of the amplifier, and the output end of the phase detector is connected to the first input end of the phase adjustment circuit; The phase detector is used to detect the phase difference between the current output by the amplifier and the standard current, and output the control signal according to the phase difference.

4. The current phase correction circuit according to claim 3, characterized in that: The phase adjustment circuit includes an RC network, a first end of the RC network is connected to the output end of the phase detector, a second end of the RC network is connected to the first input end of the amplifier, and a third end of the RC network is connected to the output end of the amplifier and the second current port respectively; The RC network is used to adjust device parameters according to the control signal output by the phase detector, and perform current phase adjustment based on the adjusted device parameters to obtain the adjusted current.

5. The current phase correction circuit according to claim 4, characterized in that: The RC network includes a first adjustable capacitor and a first resistor; The first end of the first adjustable capacitor is connected to the output end of the phase detector, the second end of the first adjustable capacitor is connected to the first input end of the amplifier, and the third end of the first adjustable capacitor is connected to the first end of the resistor; The second end of the resistor is connected to the second current port and the input end of the phase detector respectively.

6. The current phase correction circuit according to claim 4, characterized in that: The RC network includes a second adjustable capacitor and a second resistor; The first end of the second adjustable capacitor is connected to the output end of the phase detector, the second end of the second adjustable capacitor is connected to the first input end of the amplifier, and the third end of the second adjustable capacitor is connected to the second current port and the input end of the phase detector respectively; The first end of the second resistor is connected to the second end of the second adjustable capacitor, and the second end of the second resistor is connected to the third end of the second adjustable capacitor.

7. The current phase correction circuit according to claim 4, characterized in that: The phase adjustment circuit includes an LC network, a first end of the LC network is connected to the output end of the phase detector, a second end of the LC network is connected to the first input end of the amplifier, and a third end of the LC network is connected to the output end of the amplifier and the second current port respectively.

8. The current phase correction circuit according to any one of claims 3 to 7, characterized in that: The current phase correction circuit further includes a filter circuit, wherein an input end of the filter circuit is connected to an output end of the phase detector, and an output end of the filter circuit is connected to a first end of the adjustable passive device; The filtering circuit is used to filter the control signal and transmit the filtered control signal to the adjustable passive device.

9. A current sensor, characterized in that: The current sensor includes a detection probe, an amplifier, and a current phase correction circuit according to any one of claims 1 to 8.

10. The current sensor according to claim 9, characterized in that The detection probe includes an induction coil and an integrator connected to each other. The integrator is connected to the first current port of the current phase correction and the first input end of the amplifier.

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