A method of field control, a field control circuit, and a current sensor

Abstract

The application discloses an excitation control method, an excitation control circuit and a current sensor, and comprises the following steps: a control unit is provided with a preset threshold value, the control unit comprises an excitation signal for controlling the output of an excitation unit; the excitation unit outputs an excitation frequency and applies the excitation frequency to a magnetic core coil; the control unit collects a signal passing through the magnetic core coil, obtains a time when the magnetic core coil enters deep saturation, and the ratio of the time when the magnetic core coil enters deep saturation to a corresponding period is n%; when n% is located in the preset threshold value, the control unit controls the excitation unit to stop frequency conversion; when n% is not located in the preset threshold value, the control unit adjusts the excitation frequency output by the excitation unit until n% is located in the preset threshold value. This method can make each product achieve the best excitation effect, thereby eliminating the influence of residual magnetism, improving the service life of the product, and further making the leakage current detection more accurate.

Description

Technical Field

[0001] This invention relates to the field of electrical technology, specifically to an excitation control method, an excitation control circuit, and a current sensor. Background Technology

[0002] Leakage current detection is a crucial safety measure in electrical systems, used to monitor whether current is flowing through unexpected paths, thereby preventing electric shocks and equipment damage. Leakage current is typically caused by insulation failures, equipment aging, or improper operation; therefore, timely detection and correction of leakage problems are essential for maintaining the safety of electrical systems.

[0003] DC leakage current detection technology has wide applications and promising market prospects in modern electrical systems. Its main application areas include industrial automation, renewable energy systems, electric vehicles, and electrical equipment in special environments. In industrial automation, DC leakage current detection systems can be used to monitor factory equipment and machinery, improving the safety and stability of production lines. In renewable energy systems, such as solar and wind power generation systems, DC leakage current detection helps to promptly detect leakage problems in equipment such as photovoltaic panels and inverters, ensuring efficient system operation. Furthermore, in the field of electric vehicles, DC leakage current detection is a key technology for ensuring the safe operation of battery systems, crucial for the widespread adoption of electric vehicles, electric bicycles, and other similar products. With the continuous development and upgrading of electrical systems, DC leakage current detection technology is expected to see even greater market demand, becoming an important component of the power safety field.

[0004] The mainstream DC leakage current detection method currently uses magnetic modulation technology. Magnetic modulation involves applying an external excitation to a magnetic material, causing it to oscillate during magnetization. If other magnetic fields or currents are present in the surrounding environment, they will affect this oscillating magnetic moment, causing a shift in the magnetic moment oscillation. By measuring this shift, information about the measured magnetic field or current can be obtained.

[0005] The current transformer contains a magnetic core coil. During operation, the magnetic core coil needs external excitation, which provides it with an excitation frequency. Each magnetic core coil has a corresponding optimal excitation frequency. This excitation frequency should bring the magnetism to a state of deep saturation. Using this frequency ensures that the magnetism is fully saturated without remaining in a saturated state for too long. Fully saturated magnetism avoids the influence of residual magnetism on parameter accuracy, while prolonged saturation leads to wasted power.

[0006] However, the mainstream fluxgate solutions on the market specify a fixed frequency excitation signal before leaving the factory. Due to differences in size, weight, and annealing process, some products are not in a deep saturation state, while others are not in a saturation state. The inconsistent state of each product seriously affects the actual use effect and subsequent leakage current detection. Summary of the Invention

[0007] Therefore, the technical problem to be solved by this invention is how to provide the optimal excitation frequency for each product. To this end, an excitation control method is provided, comprising:

[0008] The control unit is equipped with a preset threshold and includes an excitation signal for controlling the output of the excitation unit.

[0009] An excitation unit, wherein the control unit is electrically connected to the excitation unit, and the excitation unit outputs an excitation frequency and applies it to the magnetic core coil;

[0010] The control unit collects the signal passing through the magnetic core coil and obtains the time when the magnetic core coil enters deep saturation. The ratio of the time when the magnetic core coil enters deep saturation to the period corresponding to the current excitation frequency is n%. When n% is within the range of the preset threshold, the control unit controls the excitation unit to stop frequency conversion; when n% is not within the range of the preset threshold, the control unit adjusts the excitation frequency output by the excitation unit until n% is within the range of the preset threshold.

[0011] When n% is less than the preset threshold, the excitation frequency output by the excitation unit decreases step by step; when n% is greater than the preset threshold, the excitation frequency output by the excitation unit increases step by step.

[0012] The excitation unit adjusts the output excitation frequency at least once every cycle.

[0013] When n% is within the range of the preset threshold, the control unit shall maintain the acquisition of signals passing through the magnetic core coil for at least one cycle.

[0014] The preset threshold ranges from 3% to 15%.

[0015] The control unit includes an adjustment button, and the control unit generates the excitation signal upon receiving a signal from the adjustment button.

[0016] The control unit includes a communication module, and the control unit generates the excitation signal upon receiving a signal from the communication module.

[0017] The communication module can be wired or wireless.

[0018] The control unit includes a timing detection module, which periodically detects n%.

[0019] The communication module is connected in conjunction with the APP; or the communication module is connected in conjunction with the Internet of Things.

[0020] Therefore, the technical problem to be solved by this invention is how to provide the optimal excitation frequency for each product. To this end, an excitation control circuit employs the above-described excitation control method.

[0021] Therefore, the technical problem to be solved by the present invention is how to provide the optimal excitation frequency for each product. To this end, a current sensor is provided, comprising the aforementioned excitation control circuit.

[0022] The technical solution of this invention has the following advantages:

[0023] 1. This invention provides an excitation control method. This control method first outputs an excitation frequency, then acquires the time it takes for the magnetic core coil to reach deep saturation. The ratio (n%) of this deep saturation time to the period is calculated. By comparing n% with a preset threshold, the excitation frequency is adjusted in real-time, achieving an optimal excitation frequency. Once the optimal excitation frequency is reached, frequency conversion stops, and the output frequency remains optimal to complete the product's operation. This method ensures that each product achieves optimal excitation, eliminating the influence of residual magnetism, improving product lifespan, and making leakage current detection more accurate.

[0024] 2. The excitation control method provided by this invention can quickly adjust the excitation frequency by comparing and analyzing n% in real time, thereby enabling the rapid selection of the optimal excitation frequency.

[0025] 3. The excitation control method provided by the present invention allows one excitation frequency to correspond to one or more cycles. The control unit can better obtain the time when the magnetic core coil enters deep saturation, improve the overall measurement accuracy, and thus select the optimal excitation frequency.

[0026] 4. The excitation control method provided by this invention prevents malfunctions and improves detection accuracy by setting at least one cycle. For example, in the second cycle, if n% changes and falls outside the preset threshold range, the excitation frequency will be readjusted.

[0027] 5. The excitation control method provided by the present invention allows the preset threshold range to be set according to actual needs, thereby obtaining a range that enables all products to achieve the best excitation effect.

[0028] 6. The excitation control method provided by this invention allows operators to adjust the setting of the adjustment button according to actual needs after the product leaves the factory, thereby obtaining the optimal excitation frequency. Secondly, during the use of the product, the current sensor wear may cause the excitation frequency at the factory to no longer be the optimal excitation frequency. This can be re-controlled and adjusted to the optimal excitation frequency by adjusting the button. Alternatively, during transportation or use, if the magnetic core coil is dropped or impacted, it will affect the optimal excitation frequency of the magnetic core coil. Therefore, it can also be re-controlled and adjusted to the optimal excitation frequency by adjusting the button.

[0029] 7. The excitation control method provided by the present invention provides an external control effect through a communication module, which can be wired or wireless control, thereby readjusting the optimal excitation frequency through the control unit to obtain the optimal excitation frequency.

[0030] 8. The excitation control method provided by this invention can be wired via 485 communication or other communication methods, or wirelessly via local area network, WIFI, APP, or IoT, etc., to form a wireless control effect, allowing operators to better achieve control effects and select the optimal excitation frequency.

[0031] 9. The excitation control circuit provided by the present invention has a timing detection module that enables timing detection, which can be performed daily, weekly, monthly, or quarterly, etc. The operator can select the corresponding time according to actual needs, thereby achieving a real-time adjustment effect.

[0032] 10. The present invention provides a current sensor. The current sensor adopts this circuit so that the magnetic core coil inside the current sensor can obtain the best excitation effect, improve the accuracy of leakage current detection, and at the same time reduce the damage to the magnetic core coil and improve its service life. Attached Figure Description

[0033] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0034] Figure 1 This invention provides excitation frequency and waveform diagrams generated by applying excitation frequency to magnetic core coil;

[0035] Figure 2 This invention provides excitation frequency and waveform diagrams generated by applying excitation frequency to magnetic core coil;

[0036] Figure 3This invention provides excitation frequency and waveform diagrams generated by applying excitation frequency to magnetic core coil;

[0037] Figure 4 A waveform diagram of the excitation frequency is provided for this invention;

[0038] Figure 5 This is a connection block diagram of an excitation control method provided by the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Control unit; 2. Excitation unit; 3. Magnetic core coil. Detailed Implementation

[0041] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0043] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0044] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0045] Example 1

[0046] This embodiment provides an excitation control method, as shown in the attached figure. Figure 1-5 As shown, it includes:

[0047] Control unit 1 has a preset threshold, which can be a fixed value or a range; in this embodiment, a range is preferred. The preset threshold refers to the ratio of the time it takes for the magnetic core coil 3 to enter deep saturation at the optimal excitation frequency to the corresponding period. This preset threshold can be set according to actual needs to ensure that each magnetic core coil 3 can achieve optimal excitation. Control unit 1 includes an excitation signal for controlling the excitation unit. Control unit 1 provides a signal to the excitation unit, causing the excitation unit to output an excitation frequency. In this embodiment, control unit 1 is a chip-based unit that forms the control effect.

[0048] The excitation unit 2 is electrically connected to the control unit 1, enabling the control unit 1 to control the excitation unit 2. The excitation unit 2 outputs an excitation frequency and applies it to the magnetic core coil 3, thus providing external excitation to the magnetic core coil 3. In this embodiment, the excitation unit 2 specifically outputs a square wave, which is applied to the magnetic core coil 3. Simply put, the excitation unit 2 and the magnetic core coil 3 are electrically connected, and the generated square wave interacts with the magnetic core coil 3. The excitation frequency generated by the excitation unit 2 is not limited to one or two frequencies; it is controlled by the control unit 1 and can output an excitation frequency within a range, such as any excitation frequency from 1kHz to 10kHz, or any excitation frequency from 500Hz to 15kHz. How the control unit 1 controls the excitation frequency of the excitation unit 2 is existing technology and will not be described in detail in this embodiment. The excitation unit 2 can be frequency-controlled according to the instructions of the control unit 1, meaning the excitation frequency can be changed at any time. When the magnetic core coil 3 enters deep saturation, the waveform of the magnetic core coil 3 will produce a flat line segment. This line segment is located at the top and bottom of the waveform. The time of this flat line segment is the time when the magnetic core coil 3 enters deep saturation.

[0049] Control unit 1 collects the signal passing through magnetic core coil 3 and obtains the time when magnetic core coil 3 enters deep saturation. The ratio of the time when magnetic core coil 3 enters deep saturation to the period corresponding to the excitation frequency at that time is n%. The period corresponding to this time is specifically the period corresponding to the excitation frequency. The corresponding period length can be obtained from f=1 / T.

[0050] When n% is within the preset threshold range, control unit 1 controls excitation unit 2 to stop frequency conversion. Stopping frequency conversion means stopping the change of excitation frequency and maintaining the output at this excitation frequency. When n% is within the preset threshold range, the obtained excitation frequency is the optimal excitation frequency. It should be noted that in this embodiment, the optimal excitation frequency is a range, not a fixed value under ideal conditions. This optimal excitation frequency is determined through experimental calculation and selection of the preset threshold. Using this frequency ensures that the magnetism of the magnetic core coil 3 is fully saturated and does not remain in a saturated state for too long, eliminating the influence of residual magnetism. Fully saturated magnetism avoids the influence of residual magnetism on parameter accuracy, while remaining in a saturated state for a long time leads to wasted power consumption. The optimal excitation frequency is continuously output and applied to the magnetic core coil 3.

[0051] When n% is not within the preset threshold range, control unit 1 adjusts the excitation frequency output by excitation unit 2 until n% falls within the preset threshold range. The excitation frequency is adjusted in real-time. Based on n% obtained at a given excitation frequency, it is determined whether this excitation frequency makes n% fall within the preset threshold range. If it still does not fall within the preset threshold range, the excitation frequency is adjusted further until n% falls within the preset threshold range. The optimal excitation frequency can be obtained after several adjustments, possibly ten or even dozens of times, depending on the actual situation. Therefore, it can also be considered a frequency converter, adjusting the excitation frequency in real-time to change or modify the excitation frequency.

[0052] This control method first outputs an excitation frequency, then obtains the time it takes for the magnetic core coil 3 to reach deep saturation. The ratio (n%) of this time to the period is calculated. By comparing n% with a preset threshold, the excitation frequency is adjusted in real-time, achieving an optimal excitation effect. Once the optimal excitation frequency is reached, the frequency conversion stops, completing the product's operation. This method ensures that each product achieves optimal excitation, eliminating the influence of residual magnetism, improving product lifespan, and making leakage current detection more accurate. For example, existing technologies use square waves composed of multiple different excitation frequencies. While some of these frequencies may cause the magnetic core coil 3 to reach deep saturation (the optimal excitation frequency in this embodiment), others may be lower or higher, causing the magnetic core coil 3 to remain in saturation for extended periods, resulting in wasted power and affecting lifespan. This application, however, maintains a stable output of the optimal excitation frequency, ensuring normal product operation and improving detection accuracy.

[0053] Specifically, when n% is less than a preset threshold, the excitation frequency output by excitation unit 2 decreases progressively. This progressive decrease can be an arithmetic progression, for example, an initial excitation frequency of 5 kHz, followed by a decrease of 0.1 kHz or 0.2 kHz each time. Those skilled in the art can choose the appropriate setting based on actual needs. It should also be noted that when the preset threshold is a range, if n% is less than the minimum value of the preset threshold, the excitation frequency output by excitation unit 2 decreases progressively. When n% is greater than the preset threshold, the excitation frequency output by excitation unit 2 increases progressively. This progressive decrease can be an arithmetic progression, for example, an initial excitation frequency of 5 kHz, followed by an increase of 0.1 kHz or 0.2 kHz each time. Those skilled in the art can choose the appropriate setting based on actual needs. It should also be noted that when the preset threshold is a range, if n% is greater than the maximum value of the preset threshold, the excitation frequency output by excitation unit 2 increases progressively. By comparing and analyzing n% in real time, the excitation frequency can be quickly adjusted to select the optimal frequency. Alternatively, the excitation frequency can be randomly fluctuating within the range of 1kHz-10kHz to select the best frequency. The excitation frequency can also be divided into several units, with one frequency extracted from each unit for testing.

[0054] Specifically, excitation unit 2 adjusts the output excitation frequency at least once every cycle. When an excitation frequency is applied to the magnetic core coil 3 and the calculated n% is not within the preset threshold range, another excitation frequency is immediately adjusted to form another cycle. Two adjacent cycles are connected until the optimal excitation frequency is reached, at which point excitation unit 2 stops working. When the interval is two cycles, two identical waveforms are formed. One excitation frequency corresponds to one or more cycles. Control unit 1 can better obtain the time when the magnetic core coil 3 enters deep saturation, improving the overall measurement accuracy and thus selecting the optimal excitation frequency. Those skilled in the art can select an appropriate interval according to actual needs. When the chip's computing power is sufficient, the optimal excitation frequency can be quickly obtained even with a one-cycle interval. When the chip's computing power is insufficient or a more accurate optimal excitation frequency is desired, the number of cycles can be increased to achieve precise measurement and obtain the optimal excitation frequency. Here, the chip's computing power is directly proportional to its cost.

[0055] Specifically, when n% is within a preset threshold range, the control unit 1 maintains signal acquisition for at least one cycle through the magnetic core coil 3. Setting at least one cycle prevents erroneous operations and improves detection accuracy. In this embodiment, taking three cycles of acquisition as an example, if n% is within the preset threshold range in the first cycle, and then changes in the second cycle, causing n% to fall outside the preset threshold range, the excitation frequency will be readjusted to prevent interference and ensure the optimal excitation frequency. Alternatively, acquisition can be maintained for five cycles or longer. When the control unit 1 continuously acquires signals, real-time detection and permanent detection are achieved, maintaining the optimal excitation frequency at all times. The time interval for this permanent detection is at the microsecond level, and its detection accuracy is far greater than that of timed detection.

[0056] Specifically, the preset threshold range is 3%-15%. The preset threshold range can be set according to actual needs, thus obtaining a range that allows all products to achieve optimal excitation. Those skilled in the art can determine the preset threshold range based on experimental data or practical experience; other ranges are also possible.

[0057] Specifically, the control unit 1 includes an adjustment button. The control unit 1 generates an excitation signal upon receiving a signal from the adjustment button. The adjustment button can be set so that, after the product leaves the factory, the operator can adjust it according to actual needs to obtain the optimal excitation frequency. Secondly, during product use, the current sensor may experience wear and tear (e.g., parameter changes due to core oxidation) causing the factory-set excitation frequency to no longer be optimal. This can be corrected by adjusting the button to restore the optimal excitation frequency. Furthermore, during transportation or use, if the core coil 3 is dropped or impacted, it will affect the optimal excitation frequency of the core coil 3. Therefore, this can also be corrected by adjusting the button to restore the optimal excitation frequency.

[0058] Specifically, control unit 1 includes a communication module. Control unit 1 receives signals from the communication module and generates an excitation signal. Both the communication module and the adjustment button serve an adjustment function, achieving real-time adjustment of the optimal excitation frequency. The communication module provides external control, which can be wired or wireless, allowing control unit 1 to readjust the optimal excitation frequency and obtain the desired frequency.

[0059] Specifically, the communication module can be wired or wireless. Wired connections can be via RS-485 or other communication methods, while wireless connections can be via local area network, Wi-Fi, an app, or the Internet of Things, etc. Operators can use wired or wireless methods to achieve control, allowing the magnetic core coil 3 to regain an optimal excitation frequency, thereby improving the leakage current detection capability of the magnetic core coil 3.

[0060] Specifically, control unit 1 includes a timed detection module, which performs timed detection of n%. The timed detection module achieves the effect of timed detection, which can be performed daily, weekly, monthly, or quarterly, etc. The operator can select the corresponding time according to actual needs, thereby achieving a real-time adjustment effect.

[0061] Specifically, if the saturation time obtained at the optimal excitation frequency deviates from the time set by the manufacturer, the excitation frequency is adjusted until the saturation time matches the time set by the manufacturer.

[0062] Specifically, the optimal excitation frequency has been adjusted by the excitation control method before leaving the factory, and the excitation frequency is adjusted in real time to obtain an optimal excitation frequency. This control and adjustment method has been described in detail in Example 1, so it will not be described in this example.

[0063] After the current sensor leaves the factory, due to losses (such as changes in parameters caused by core oxidation), the excitation frequency may no longer be the optimal frequency. In this case, the excitation frequency needs to be changed. This can be achieved by sending an adjustment signal to control unit 1 via an adjustment button or communication module, thereby obtaining a new optimal excitation frequency. The communication module can work with an app or the Internet of Things (IoT) to achieve wireless control, allowing operators to better control the device and select the optimal excitation frequency. Furthermore, integration with the IoT enables big data control, achieving real-time monitoring.

[0064] In addition, when the current sensor is dropped or impacted, it will also affect the parameters of the magnetic core coil 3, which will also cause the excitation frequency at the factory to no longer be the optimal excitation frequency. This can also be adjusted through the above operation methods.

[0065] Compared to existing technologies, current sensors are manufactured with a fixed excitation frequency that remains unchanged until the end of their lifespan. In this embodiment, the current sensor is monitored and adjusted in real time, ensuring that the magnetic core coil 3 within the current sensor always maintains the optimal excitation frequency, thereby improving the accuracy of leakage current detection. Furthermore, this design also extends the lifespan of the current sensor.

[0066] Example 2

[0067] This invention provides an excitation control circuit that employs the excitation control method described in Embodiment 1. The excitation control circuit is located on a circuit board and, through the cooperation of chips and other components, forms an integrated circuit. Simultaneously, a control program is programmed into the chip, enabling the search for the optimal excitation frequency through software and hardware collaboration. Those skilled in the art can easily conceive of the relevant hardware layout and program writing based on this embodiment; therefore, it will not be described in detail here.

[0068] Example 3

[0069] This invention provides a current sensor, including an excitation control circuit. The excitation control circuit is located on a circuit board, which can be housed inside the current sensor or located outside the current sensor as a relatively independent unit. The current sensor is electrically connected to the circuit board. This circuit design allows the magnetic core coil 3 inside the current sensor to achieve optimal excitation, improving the accuracy of leakage current detection, while also reducing damage to the magnetic core coil 3 and extending its service life.

[0070] Specifically, the magnetic core coil 3 is also located inside the current sensor, which is existing technology; therefore, the connection and fixing relationship between the magnetic core coil 3 and the current sensor will not be described in detail in this embodiment. The current sensor here may include a current transformer, or it may be a current detection structure of other types.

[0071] Specifically, in addition to the components in this embodiment, the circuit board also includes a leakage current detection unit, an alarm unit, etc., which are existing technologies and therefore will not be described in detail in this embodiment. Furthermore, the circuit board for detecting leakage current and the circuit board containing the excitation control circuit are two independent circuit boards, electrically connected by conductive components.

[0072] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An excitation control method, characterized in that, include: Control unit (1), the control unit (1) is provided with a preset threshold, the control unit (1) includes an excitation signal for controlling the output of the excitation unit (2); The excitation unit (2) is electrically connected to the control unit (1), and the excitation unit (2) outputs an excitation frequency and applies it to the magnetic core coil (3); The control unit (1) collects the signal passing through the magnetic core coil (3) and obtains the time when the magnetic core coil (3) enters deep saturation. When the magnetic core coil (3) enters deep saturation, the waveform of the magnetic core coil (3) produces a flat line segment. The time of this flat line segment is the time when the magnetic core coil (3) enters deep saturation. The ratio of the time when the magnetic core coil (3) enters deep saturation to the period corresponding to the excitation frequency at that time is n%. When n% is within the range of the preset threshold, the control unit (1) controls the excitation unit (2) to stop frequency conversion. When n% is not within the range of the preset threshold, the control unit (1) adjusts the excitation frequency output by the excitation unit (2) until n% is within the range of the preset threshold.

2. The excitation control method according to claim 1, characterized in that, When n% is less than the preset threshold, the excitation frequency output by the excitation unit (2) decreases step by step; when n% is greater than the preset threshold, the excitation frequency output by the excitation unit (2) increases step by step.

3. The excitation control method according to claim 1, characterized in that, The excitation unit (2) adjusts the output excitation frequency at least once every cycle.

4. The excitation control method according to claim 1, characterized in that, When n% is within the range of the preset threshold, the control unit (1) shall at least maintain the acquisition of a signal passing through the magnetic core coil (3) for one cycle.

5. The excitation control method according to claim 1, characterized in that, The preset threshold ranges from 3% to 15%.

6. The excitation control method according to claim 1, characterized in that, The control unit (1) includes an adjustment button, and the control unit (1) generates the excitation signal upon receiving a signal from the adjustment button.

7. The excitation control method according to claim 1, characterized in that, The control unit (1) includes a communication module, and the control unit (1) generates the excitation signal upon receiving a signal from the communication module.

8. The excitation control method according to claim 7, characterized in that, The communication module is connected in conjunction with the APP; or the communication module is connected in conjunction with the Internet of Things.

9. An excitation control circuit, characterized in that, The excitation control method described in any one of claims 1-8 is adopted.

10. A current sensor, characterized in that, Includes the excitation control circuit as described in claim 9.

Images