A magnetic control type reactive power compensation control method based on subsection loss optimization

Abstract

This invention discloses a magnetically controlled reactive power compensation control method based on segmented loss optimization, relating to the field of reactive power compensation technology in power systems. The method includes the following steps: Step S1, grid signal acquisition and reactive power calculation; Step S2, segmented loss mathematical model of the magnetically controlled reactor; Step S3, optimal excitation current solution based on loss minimization; Step S4, fuzzy adaptive PID hybrid control; Step S5, dynamic continuous reactive power compensation; and Step S6, harmonic current feedforward suppression. This invention employs the aforementioned magnetically controlled reactive power compensation control method based on segmented loss optimization. By establishing an accurate segmented loss mathematical model, using an excitation current optimization algorithm based on loss minimization, and combining a fuzzy adaptive PID hybrid control strategy and adaptive gain harmonic current feedforward suppression technology, it achieves low-loss, fast-response, and low-harmonic operation of the magnetically controlled reactive power compensation.

Description

Technical Field

[0001] This invention relates to the field of reactive power compensation technology in power systems, and in particular to a magnetically controlled reactive power compensation control method based on segmented loss optimization. Background Technology

[0002] Magnetic control reactive power compensation technology is a dynamic compensation technology that adjusts reactive power by changing the magnetic saturation of the reactor core. It has the advantages of simple structure, high reliability, convenient maintenance and low cost, and is widely used in 10kV~35kV distribution networks, wind farms, photovoltaic power stations, electrified railways and other occasions.

[0003] However, traditional magnetically controlled reactive power compensation control methods have three main drawbacks: High losses: Traditional methods do not consider a precise segmented loss model for the magnetically controlled reactor. Excitation current adjustment is solely aimed at meeting reactive power demand, resulting in extremely uneven core magnetic flux density distribution, with excessively high flux density in some areas, significantly increasing core losses. Simultaneously, the DC excitation current is too large, leading to high winding copper losses. Under rated load, the total loss of traditional magnetically controlled reactive power compensation devices typically accounts for 1.5% to 2.5% of their capacity, resulting in significant energy waste over long-term operation. Slow response speed: Traditional methods generally employ fixed-parameter PI control strategies, which are difficult to adapt to rapid changes in grid reactive power. Response times are typically above 100ms, failing to meet the rapid reactive power compensation requirements of wind power, photovoltaic, and other new energy sources, as well as impulsive loads. High harmonic content: Traditional methods do not employ effective harmonic suppression measures. During adjustment, the magnetically controlled reactor generates a large number of odd harmonics such as the 3rd, 5th, and 7th orders, with a total harmonic distortion rate typically exceeding 8%, severely polluting the power quality of the grid. Summary of the Invention

[0004] The purpose of this invention is to provide a magnetically controlled reactive power compensation control method based on segmented loss optimization, which achieves low loss, fast response and low harmonic operation of magnetically controlled reactive power compensation.

[0005] This invention provides a magnetically controlled reactive power compensation control method based on segmented loss optimization, comprising the following steps: Step S1: Power grid signal acquisition and reactive power calculation; real-time acquisition of three-phase voltage and three-phase current signals of the power grid, and calculation of instantaneous reactive power and reactive power deviation of the power grid through coordinate transformation; Step S2: Mathematical model of segmented loss of magnetically controlled reactor; Establish a mathematical model of segmented loss of magnetically controlled reactor, and calculate the hysteresis loss, eddy current loss, additional loss, AC winding copper loss and DC excitation winding copper loss of each section of the core under different DC excitation currents. Step S3: Solving for the optimal excitation current based on loss minimization; Based on the principle of loss minimization, an optimization problem with inductance and current constraints is constructed, and the optimal DC excitation current reference value is solved using the improved Newton-Raphson iterative method. Step S4: Fuzzy Adaptive PID Hybrid Control; A fuzzy adaptive PID hybrid control strategy is adopted to adjust the PID control parameters in real time according to the reactive power deviation and the rate of change of the deviation, thereby generating the actual DC excitation current control signal. Step S5: Dynamic and continuous reactive power compensation; Adjust the inductance value of the magnetically controlled reactor according to the actual DC excitation current control signal to achieve dynamic and continuous reactive power compensation. Step S6: Harmonic current feedforward suppression; Real-time detection of each harmonic current generated during the compensation process, and the generation of harmonic compensation current using an adaptive gain harmonic current feedforward suppression algorithm to reduce the harmonic content of the power grid.

[0006] Preferably, in step S1, the method for calculating the instantaneous reactive power of the power grid first converts the voltage and current signals in the three-phase stationary coordinate system into components in the α-β stationary coordinate system through Clark transformation, as shown in the following formula: ; ; in, , The voltage component is in the α-β coordinate system; , The current component is in the α-β coordinate system; Then, the instantaneous reactive power of the power grid is calculated based on the instantaneous reactive power theory, as shown in the following formula: ; in, The instantaneous reactive power of the power grid; The instantaneous reactive power is low-pass filtered to obtain the average reactive power. The reactive power deviation is calculated as shown in the following formula: ; in, This refers to reactive power deviation.

[0007] Preferably, in step S2, the mathematical model for the segmented loss of the magnetically controlled reactor is as follows: ; in, The total loss of the magnetically controlled reactor is the DC excitation current. The function; For the first k Losses in the iron core section; For AC winding copper loss; This refers to the copper loss of the DC excitation winding.

[0008] Preferred, the first k The loss calculation for the iron core section is shown in the following formula: ; in, This is the hysteresis loss coefficient; This is the eddy current loss coefficient; This is the additional loss factor; For the first k The magnetic flux density of the iron core.

[0009] Preferably, the calculation of copper loss in the DC excitation winding is as follows: ; in, The resistance of the DC excitation winding; For the first k Number of turns in the excitation winding; For the first k Average turn length of the winding segment.

[0010] Preferably, in step S3, the optimal DC excitation current is solved based on minimizing losses, with the objective function being the minimization of the total losses of the magnetically controlled reactor, as shown in the following equation: ; in, This is the minimize operator; This represents the total loss of the magnetically controlled reactor. For the first k Iron loss in the core section; For copper losses in AC windings; For the copper loss of the DC excitation winding; The solution process requires satisfying two constraints simultaneously: the inductance value of the magnetically controlled reactor must be equal to the reference inductance value that meets the reactive power compensation requirements. DC excitation current From 0 to the maximum permissible DC excitation current Within the range.

[0011] Preferably, the reference inductance value The calculation is shown in the following formula: ; in, This represents the effective value of the phase voltage of the power grid.

[0012] Preferably, in step S3, the iterative formula of the improved Newton-Raphson iterative method is as follows: ; in, For the first k The DC excitation current value for the next iteration; and These are the first and second derivatives of the total loss with respect to the DC excitation current, respectively; and These are the first and second derivatives of the inductance value with respect to the DC excitation current, respectively; For Lagrange multipliers; This is the iteration step size factor.

[0013] Therefore, the present invention adopts the above-mentioned magnetically controlled reactive power compensation control method based on segmented loss optimization, which realizes low loss, fast response and low harmonic operation of magnetically controlled reactive power compensation.

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall process of a magnetically controlled reactive power compensation control method based on segmented loss optimization according to the present invention. Figure 2 The total loss comparison curves of two control methods under different load rates in the magnetically controlled reactive power compensation control method based on segmented loss optimization of the present invention are shown. Figure 3 The image shows a comparison curve of response time and steady-state error between two control methods in a magnetically controlled reactive power compensation control method based on segmented loss optimization, as presented in this invention. Figure 4 This is a bar chart comparing the harmonic content of two control methods under rated load in a magnetically controlled reactive power compensation control method based on segmented loss optimization according to the present invention. Detailed Implementation

[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0018] The terms "first," "second," and similar words used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0019] Example 1 like Figures 1-4 As shown, the present invention provides a magnetically controlled reactive power compensation control method based on segmented loss optimization, comprising the following steps: Step S1: Grid signal acquisition and reactive power calculation; real-time acquisition of instantaneous three-phase voltage values ​​of the grid. , , and three-phase current signal , , The signal, with a sampling frequency of 10kHz, is used to calculate the instantaneous reactive power and reactive power deviation of the power grid through coordinate transformation.

[0020] In step S1, the instantaneous reactive power of the power grid is calculated by first converting the voltage and current signals in the three-phase stationary coordinate system into components in the α-β stationary coordinate system using Clark transformation, as shown in the following equation: .

[0021] .

[0022] in, , The voltage component is in the α-β coordinate system; , The current component is in the α-β coordinate system.

[0023] Then, the instantaneous reactive power of the power grid is calculated based on the instantaneous reactive power theory, as shown in the following formula: .

[0024] in, This refers to the instantaneous reactive power of the power grid.

[0025] The instantaneous reactive power is low-pass filtered with a cutoff frequency of 50Hz to obtain the average reactive power. , =-700 kvar (Inductive reactive power), setting the reference reactive power required by the power grid. =700 kvar (Capacitive) and calculate the reactive power deviation as shown in the following formula: .

[0026] in, This refers to reactive power deviation.

[0027] =700 - (-700) = 1400 kvar.

[0028] Step S2: Mathematical model of segmented loss of magnetically controlled reactor; Establish a mathematical model of segmented loss of magnetically controlled reactor, and calculate the hysteresis loss, eddy current loss, additional loss, AC winding copper loss and DC excitation winding copper loss of each section of the core under different DC excitation currents.

[0029] The parameters of the magnetically controlled reactor are: number of core segments. n =2, number of segments in the excitation winding m =2, cross-sectional area of ​​iron core S =0.04m2, number of turns in AC winding N =800 turns, total length of iron core magnetic circuit l =2.5m, total length of non-magnetic air gap δ =0.002m, number of turns of the upper excitation winding N 1 = 300 turns, number of turns in the lower excitation winding N 2 = 200 turns, average turn length of the upper winding l 1=1.2m, average turn length of the lower winding l 2 = 1.0m, conductor cross-sectional area S w =10mm 2 resistivity of copper wire ρ =1.75×10 -8 Ω·m, power grid frequency f =50Hz.

[0030] In step S2, the mathematical model for the segmented loss of the magnetically controlled reactor is shown in the following equation: .

[0031] in, The total loss of the magnetically controlled reactor is the DC excitation current. The function; For the first k Losses in the iron core section; For AC winding copper loss; This refers to the copper loss of the DC excitation winding.

[0032] No. k The loss calculation for the iron core section is shown in the following formula: .

[0033] in, This is the hysteresis loss coefficient. =0.023 W / ( T 2 · H z). The eddy current loss coefficient is... =1.2×10 -5 3 W / ( T 2 · H z 2 ), For additional loss coefficient, =0.007 W / ( T 1.5 · H z 1.5 ), For the first k The magnetic flux density of the iron core.

[0034] The calculation of copper loss in DC excitation winding is shown in the following formula: .

[0035] in, The resistance of the DC excitation winding; For the first k Number of turns in the excitation winding; For the first k Average turn length of the winding segment.

[0036] Substitute the parameters to calculate the DC excitation winding resistance, as shown in the following formula: .

[0037] The copper loss of the AC winding is shown in the following formula: .

[0038] in, For AC winding current; For AC winding resistance, =0.12 .

[0039] Step S3: Solving for the optimal excitation current based on loss minimization; Based on the principle of loss minimization, construct an optimization problem with inductance and current constraints, and use the improved Newton-Raphson iterative method to solve for the optimal DC excitation current reference value.

[0040] The relationship between the inductance of a magnetically controlled reactor and the DC excitation current is shown in the following formula: .

[0041] in, The permeability of free space, =4π×10⁻⁷H / m, The relative permeability of the iron core is denoted by , and the DC excitation current is denoted by . The nonlinear function can be obtained by fitting the magnetization curve of the iron core.

[0042] Based on reactive power demand, refer to the inductance value. The calculation is shown in the following formula: .

[0043] in, This represents the effective value of the phase voltage of the power grid. =10000 / V. Substituting the numerical values, we get ≈47.62 mH .

[0044] The objective of minimizing losses is established as follows: the objective function is to minimize the total loss of the magnetically controlled reactor, as shown in the following equation: .

[0045] in, This is the minimize operator; This represents the total loss of the magnetically controlled reactor. For the first k Iron loss in the core section; For copper losses in AC windings; This refers to the copper loss of the DC excitation winding.

[0046] The solution process requires satisfying two constraints simultaneously: the inductance value of the magnetically controlled reactor must be equal to the reference inductance value that meets the reactive power compensation requirements. =47.62 mH DC excitation current From 0 to the maximum permissible DC excitation current =5A range.

[0047] In step S3, the iterative formula of the improved Newton-Raphson iterative method is shown in the following equation: ; in, For the first k The DC excitation current value for the next iteration; and These are the first and second derivatives of the total loss with respect to the DC excitation current, respectively; and These are the first and second derivatives of the inductance value with respect to the DC excitation current, respectively; For Lagrange multipliers; This is the iteration step size factor. =0.8.

[0048] The iterative convergence condition is shown in the following equation: .

[0049] .

[0050] in, For the first k The DC excitation current value obtained from +1 iterations; For the first k The DC excitation current value obtained from the next iteration.

[0051] After three iterations, the algorithm converges, yielding a DC excitation current reference value based on loss minimization. At this point, the total loss of the magnetically controlled reactor is as follows: .

[0052] When using the traditional control method, under the same reactive power compensation capacity, the DC excitation current is 4.1A, and the total loss using the traditional control method is... As shown in the following formula: .

[0053] The total loss is reduced, as shown in the following formula: .

[0054] in, This represents the rate of reduction in losses.

[0055] Step S4: Fuzzy Adaptive PID Hybrid Control; A fuzzy adaptive PID hybrid control strategy is adopted to adjust the PID control parameters in real time according to the reactive power deviation and the rate of change of the deviation, thereby generating the actual DC excitation current control signal.

[0056] The initial values ​​for the PID parameters are set as follows: K p0 =0.6; K i0 =0.12, Kd0 =0.06. Based on reactive power deviation e (t) and rate of change of deviation ec (t), the PID parameters are adjusted in real time using the fuzzy rule base, as shown in the following formula: .

[0057] .

[0058] .

[0059] in, , , PID parameters are adjusted in real time; , , This is the parameter correction amount output by the fuzzy controller.

[0060] Input variables of fuzzy controller and and output variables , , All use 7 fuzzy subsets: {NB, NM, NS, ZO, PS, PM, PB}.

[0061] In step S4, the output of the fuzzy adaptive PID hybrid control strategy is shown in the following equation: .

[0062] .

[0063] in, This is the output correction value of the fuzzy adaptive PID controller; This refers to reactive power deviation. This is a reference value for the DC excitation current obtained based on minimizing losses; This is the integral operation of the error signal.

[0064] .

[0065] in, This refers to reactive power deviation.

[0066] The final DC excitation current control signal is shown in the following formula: .

[0067] in, This is the final output DC excitation current control signal; =3.2A.

[0068] When the reactive power deviation is large, increase the proportional coefficient and the derivative coefficient to improve the response speed; when the reactive power deviation is small, increase the integral coefficient to eliminate steady-state error.

[0069] Step S5: Dynamic continuous compensation of reactive power; adjust the inductance value of the magnetically controlled reactor according to the actual DC excitation current control signal to achieve dynamic continuous compensation of reactive power.

[0070] The DC excitation current control signal is input to the PWM rectifier to generate an actual DC excitation current of 3.2A. The inductance value of the magnetically controlled reactor is adjusted to 47.62mH to absorb inductive reactive power, as shown in the following formula: .

[0071] in, This represents the effective value of the phase voltage of the power grid. This is the inductance value of the magnetically controlled reactor.

[0072] Fixed capacitive reactive power The total compensated reactive power is shown in the following formula: .

[0073] in, For total reactive power compensation; The inductive reactive power absorbed by the magnetically controlled reactor.

[0074] Step S6: Harmonic current feedforward suppression; Real-time detection of each harmonic current generated during the compensation process, and the generation of harmonic compensation current using an adaptive gain harmonic current feedforward suppression algorithm to reduce the harmonic content of the power grid.

[0075] Harmonic currents generated by a magnetically controlled reactor are detected using Fast Fourier Transform (FFT). In step S6, the adaptive gain harmonic current feedforward suppression algorithm is shown in the following equation: .

[0076] .

[0077] in, For harmonic compensation current; The adaptive gain coefficient for the nth harmonic; The nth harmonic current detected on the side of the magnetically controlled reactor; G represents the initial gain coefficient of the nth harmonic; 30 =0.95, G 50 =0.92, G 70 =0.88, The integral coefficient is... =0.01; This refers to the nth harmonic current on the power grid side. This is the reference value for the nth harmonic current. =0.

[0078] The detected 3rd harmonic current from the magnetically controlled reactor was 14A, the 5th harmonic current was 7A, and the 7th harmonic current was 3.5A. Harmonic compensation currents were generated using an adaptive gain harmonic current feedforward suppression algorithm. After compensation, the 3rd harmonic current decreased to 0.56A, the 5th harmonic current decreased to 0.42A, and the 7th harmonic current decreased to 0.28A. The total harmonic distortion rate decreased from 9.2% to 1.8%.

[0079] To fully verify its effectiveness, a 10kV / 1000kvar magnetically controlled reactive power compensation experimental platform was built, and multiple sets of comparative experiments were conducted using both traditional control methods and segmented loss optimization control methods.

[0080] The main parameters of the experimental platform are as follows: mains voltage: 10kV, 50Hz; rated capacity of magnetically controlled reactor: 1000kvar; fixed capacitor compensation capacity: 1000kvar; sampling frequency: 10kHz; controller: DSP TMS320F28335.

[0081] Loss Comparison Experiment: The total loss of the traditional control method and the segmented loss optimization control method was measured at load rates of 20%, 50%, 80%, and 100%, respectively. The experimental results are shown in the table below: Table 1. Comparison of total losses between the two control methods under different load rates.

[0082] As can be seen from Table 1, the total loss of the segmented loss optimization control method is significantly lower than that of the traditional control method throughout the entire load range, and the lower the load rate, the more obvious the loss reduction effect.

[0083] Under low load conditions, the DC excitation current of traditional control methods is too large, which leads to a significant increase in winding copper losses and core losses. However, the segmented loss optimization control method can minimize the total loss while meeting reactive power requirements by optimizing the excitation current.

[0084] Response time comparison experiment: Under the condition of a sudden change of 700 kvar in the reactive power of the power grid, the response time of the traditional control method and the segmented loss optimization control method were measured respectively. The experimental results are shown in the table below: Table 2 Comparison of Response Time and Steady-State Error between the Two Control Methods

[0085] As can be seen from Table 2, the response time of the segmented loss optimization control method is only 14ms, which is 87.8% shorter than that of the traditional control method. At the same time, the steady-state error is reduced from ±25kvar to ±5kvar, and the control accuracy is significantly improved.

[0086] Harmonic contrast experiment: Under rated load, the amplitude of each harmonic current and the total harmonic distortion rate were measured for both the traditional control method and the segmented loss optimization control method.

[0087] The experimental results are shown in the table below: Table 3. Comparison of Harmonic Content between Two Control Methods under Rated Load

[0088] As can be seen from Table 3, the segmented loss optimization control method has a good suppression effect on all harmonics, especially the 3rd and 5th harmonics, with suppression rates of 96.0% and 94.0% respectively. The total harmonic distortion rate was reduced from 9.2% to 1.8%, which greatly improved the power quality of the power grid.

[0089] Therefore, the present invention adopts the above-mentioned magnetically controlled reactive power compensation control method based on segmented loss optimization. By establishing an accurate mathematical model of segmented loss, adopting an excitation current optimization algorithm based on loss minimization, and combining a fuzzy adaptive PID hybrid control strategy and adaptive gain harmonic current feedforward suppression technology, the low-loss, fast-response and low-harmonic operation of magnetically controlled reactive power compensation is realized.

[0090] The above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention; and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A magnetic control type reactive power compensation control method based on segment loss optimization, characterized by, Includes the following steps: Step S1: Power grid signal acquisition and reactive power calculation; real-time acquisition of three-phase voltage and three-phase current signals of the power grid, and calculation of instantaneous reactive power and reactive power deviation of the power grid through coordinate transformation; Step S2: Mathematical model of segmented loss of magnetically controlled reactor; Establish a mathematical model of segmented loss of magnetically controlled reactor, and calculate the hysteresis loss, eddy current loss, additional loss, AC winding copper loss and DC excitation winding copper loss of each section of the core under different DC excitation currents. Step S3: Solve for the optimal excitation current based on minimizing losses; Based on the principle of minimizing losses, an optimization problem with inductance and current constraints is constructed, and the optimal DC excitation current reference value is solved by an improved Newton-Raphson iterative method. Step S4: Fuzzy Adaptive PID Hybrid Control; A fuzzy adaptive PID hybrid control strategy is adopted to adjust the PID control parameters in real time according to the reactive power deviation and the rate of change of the deviation, thereby generating the actual DC excitation current control signal. Step S5: Dynamic and continuous reactive power compensation; Adjust the inductance value of the magnetically controlled reactor according to the actual DC excitation current control signal to achieve dynamic and continuous reactive power compensation. Step S6: Harmonic current feedforward suppression; Real-time detection of each harmonic current generated during the compensation process, and the generation of harmonic compensation current using an adaptive gain harmonic current feedforward suppression algorithm to reduce the harmonic content of the power grid.

2. The magnetic control type reactive power compensation control method based on segment loss optimization according to claim 1, characterized in that, In step S1, the instantaneous reactive power of the power grid is calculated by first converting the voltage and current signals in the three-phase stationary coordinate system into components in the α-β stationary coordinate system using Clark transformation, as shown in the following equation: ； ； wherein , are voltage components in an α-β coordinate system; , are current components in an α-β coordinate system; Then, the instantaneous reactive power of the power grid is calculated based on the instantaneous reactive power theory, as shown in the following formula: ； in, The instantaneous reactive power of the power grid; The instantaneous reactive power is low-pass filtered to obtain the average reactive power. The reactive power deviation is calculated as shown in the following formula: ； in, This refers to reactive power deviation.

3. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 2, characterized in that, In step S2, the mathematical model for the segmented loss of the magnetically controlled reactor is shown in the following equation: ； in, The total loss of the magnetically controlled reactor is the DC excitation current. The function; For the first k Loss in the iron core section; For AC winding copper loss; This refers to the copper loss of the DC excitation winding.

4. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 3, characterized in that, No. k The loss calculation for the iron core section is shown in the following formula: ； in, This is the hysteresis loss coefficient; The eddy current loss coefficient is used. This is the additional loss factor; For the first k The magnetic flux density of the iron core.

5. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 4, characterized in that, The calculation of copper loss in DC excitation winding is shown in the following formula: ； in, The resistance of the DC excitation winding; For the first k Number of turns in the excitation winding; For the first k Average turn length of the winding segment.

6. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 5, characterized in that, In step S3, the optimal DC excitation current is solved based on minimizing losses, with the objective function being the minimization of the total losses of the magnetically controlled reactor, as shown in the following equation: ； in, This is the minimize operator; This represents the total loss of the magnetically controlled reactor. For the first k Iron loss in the core section; For copper losses in AC windings; For the copper loss of the DC excitation winding; The solution process requires satisfying two constraints simultaneously: the inductance value of the magnetically controlled reactor must be equal to the reference inductance value that meets the reactive power compensation requirements. DC excitation current From 0 to the maximum permissible DC excitation current Within the range.

7. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 6, characterized in that, Reference inductance value The calculation is shown in the following formula: ； in, This represents the effective value of the phase voltage of the power grid.

8. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 7, characterized in that, In step S3, the iterative formula of the improved Newton-Raphson iterative method is shown in the following equation: ； in, For the first k The DC excitation current value for the next iteration; and These are the first and second derivatives of the total loss with respect to the DC excitation current, respectively; and These are the first and second derivatives of the inductance value with respect to the DC excitation current, respectively; For Lagrange multipliers; This is the iteration step size factor.

9. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 8, characterized in that, In step S4, the output of the fuzzy adaptive PID hybrid control strategy is shown in the following equation: ； ； in, This is the output correction value of the fuzzy adaptive PID controller; This refers to reactive power deviation. This is the reference value for DC excitation current obtained based on minimizing losses.

10. The magnetically controlled reactive power compensation control method based on segmented loss optimization according to claim 9, characterized in that, In step S6, the adaptive gain harmonic current feedforward suppression algorithm is shown in the following equation: ； ； in, For harmonic compensation current; The adaptive gain coefficient for the nth harmonic; The nth harmonic current detected on the side of the magnetically controlled reactor; is the initial gain coefficient for the nth harmonic; The integral coefficient; This refers to the nth harmonic current on the power grid side. This is the reference value for the nth harmonic current.

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