Parallel multi-topology power quality treatment method based on position tracking LMI

Abstract

The invention relates to a position tracking LMI-based parallel multiple topology power quality treatment method, which comprises the following steps of: establishing an RPC amplitude-phase control model for a locomotive traction power supply system based on a parallel multiple RPC topological structure; stable progressive position tracking is realized by constructing a state space model, designing LMI constraint and feed-forward compensation, and constructing an LMI controller which takes d-axis modulation voltage and q-axis modulation voltage as inputs and direct-current bus voltage and phase synchronization signals as outputs. Compared with the prior art, the method has the advantages of realizing optimal control and multi-target collaborative optimization of the traction power supply system and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a parallel multiple topology power quality management method based on location tracking LMI. Background Art

[0002] Traction power supply technology plays a crucial role in the new era of high-speed rail. With the continuous development of railway transportation and the widespread application of power electronics, the scale and complexity of traction power supply systems are increasing. However, the presence of various types of nonlinear loads in traction substations and various locomotives in rail transit can cause significant power quality issues.

[0003] Harmonic pollution is a major issue. Harmonic currents can cause grid voltage distortion, increase line losses, and affect the normal operation of electrical equipment, potentially even causing equipment failures and malfunctioning of protective devices. Furthermore, the presence of reactive power can negatively impact the traction power supply system, manifesting itself in a reduced system power factor and increased grid losses.

[0004] Traditional methods for addressing these power quality issues include using passive power filters (PPFs). However, these filters have limitations, such as filtering only specific harmonics, being prone to grid resonance, and having limited compensation effectiveness. This is where active power filters (APFs) come in. APFs offer advantages such as fast dynamic response, high compensation accuracy, and the ability to simultaneously compensate for harmonics and reactive power.

[0005] However, the use of active power filters (APFs) alone has inherent drawbacks such as high cost and limited compensation capacity.

[0006] Chinese patent application publication number CN118842015A discloses a power quality management method and system based on multiple RPCs. By implementing negative-sequence and harmonic compensation in high-speed railways, the multiple RPC system addresses energy waste and grid instability caused by harmonic currents during EMU operation, achieving grid current balance and voltage stability, and improving energy utilization and equipment life. However, the amplitude and phase control of constrained LMIs (LMIs) in traction power supply systems suffers from several drawbacks: limited optimization freedom, and a fixed gain structure that cannot dynamically balance multiple conflicting objectives, such as position tracking accuracy (DC voltage / phase error), interference rejection (H∞ performance), and circulating current suppression, leading to tracking overshoot and excessive circulating current under regenerative braking conditions; weak dynamic adaptability, resulting in delayed response to grid voltage fluctuations and sudden load changes, inferior to the real-time optimization capabilities of position-tracking LMIs; and rigid disturbance suppression, with the preset static H∞ constraints unable to adapt to sudden regenerative braking energy changes, resulting in a worse voltage fluctuation rate than position-tracking LMIs. These drawbacks significantly degrade the overall performance of these systems under dynamic high-speed rail conditions.

[0007] In summary, in order to meet the power quality requirements of the traction power supply system, it is of great practical significance to design a power quality management method based on a parallel multiple RPC topology structure. Summary of the Invention

[0008] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a parallel multiple topology power quality management method based on position tracking LMI to solve or partially solve problems such as harmonic amplification and excessive negative sequence imbalance.

[0009] The purpose of the present invention can be achieved by the following technical solutions:

[0010] One aspect of the present invention provides a method for managing power quality in a parallel multiple topology based on location tracking LMI, comprising the following steps:

[0011] For the locomotive traction power supply system, an RPC amplitude and phase control model is established based on the parallel multiple RPC topology structure;

[0012] By constructing a state-space model, designing LMI constraints and feedforward compensation, an LMI controller is constructed with d-axis modulation voltage and q-axis modulation voltage as input and DC bus voltage and phase synchronization signal as output to achieve stable progressive position tracking.

[0013] As a preferred technical solution, the construction process of the RPC amplitude-phase control model includes the following steps:

[0014] Establish the steady-state mathematical model of the single-side voltage source converter of the railway power conditioner RPC;

[0015] Calculate the detected load current of the two arms;

[0016] Calculate the compensated bilateral traction current;

[0017] Get the total compensation current of the RPC system.

[0018] As a preferred technical solution, the steady-state mathematical model is:

[0019]

[0020] Among them, i d 、i q 、u dc are the d-axis and q-axis currents and DC voltages of the single-side voltage source converter of the railway power conditioner RPC, R, L, and C are resistance, inductance, and capacitance, respectively. ω is the angular frequency, and k c is the voltage u c The amplitude adjustment coefficient, δ is the inverter output u s The phase angle, Us is the reference vector u s Valid values.

[0021] As a preferred technical solution, the load current of the two arms is:

[0022]

[0023] Among them, i αr 、i βr are the load currents of the two arms, I αrf and I βrf is the fundamental current amplitude, I αrn and I βrn is the nth harmonic current amplitude, θ α and θ β is the phase difference, which is positive when the load is capacitive and negative when the load is inductive. αn ,θ βn is the initial phase on both sides of the nth harmonic, ω is the angular frequency, and t represents time.

[0024] As a preferred technical solution, the compensated bilateral traction current is:

[0025]

[0026] Among them, i′ α , i′ β They are the compensated bilateral traction currents, I p ′ represents the active current amplitude after active power transfer balance, ω is the angular frequency, and t represents time.

[0027] As a preferred technical solution, the total compensation current of the RPC system is:

[0028]

[0029] in, are the compensation currents on both sides of the RPC system, i′ α , i′ β They are the compensated bilateral traction currents, i αr 、i βr are the load currents of the two arms respectively.

[0030] As a preferred technical solution, the state space model is modeled as follows:

[0031]

[0032] Where x(t)∈R n is the system state vector, including d-axis current, q-axis current, DC voltage error and DC voltage integral compensation term; u(t)∈Rm is the control input, including the d-axis modulation voltage and the q-axis modulation voltage, d(t) is the external disturbance, including the train power step, grid voltage amplitude change and braking feedback power; y(t) is the output, including the DC link voltage and the grid phase angle obtained by position tracking; A, B, C, D are the system parameter matrices.

[0033] As a preferred technical solution, the LMI controller is in the form of:

[0034] u(t)=Kx(t)+K r r(t)

[0035] Among them, K is the feedback gain matrix, K r is the feedforward gain matrix, r(t) is the reference signal, including the set voltage and ideal phase.

[0036] As a preferred technical solution, the feedback gain matrix is ​​solved under stability constraints and H∞ performance constraints, and the feedforward gain matrix is ​​solved by feedforward compensation, wherein,

[0037] The stability constraints are:

[0038]

[0039] Where T represents transpose, P is a symmetric positive definite matrix;

[0040] The H∞ performance constraint is:

[0041]

[0042] Where γ is the disturbance suppression level, I is the unit matrix,

[0043] The feedforward gain matrix is ​​solved using the following formula:

[0044] K r =(C[-(A+BK)] -1 B) -1

[0045] Where, () -1 Indicates inversion.

[0046] Another aspect of the present invention provides an electronic device comprising one or more processors, a memory and one or more programs stored in the memory, wherein the one or more programs include instructions for executing the aforementioned parallel multiple topology power quality management method based on location tracking LMI.

[0047] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0048] (1) Optimizing control of the traction power supply system: The present invention adds a parallel multiplexed RPC topology to the locomotive traction power supply system. The RPC is connected in parallel to the traction power supply network, and each converter independently undertakes the compensation task of the corresponding power supply area. When the system is in operation, each traction line is equivalent to a single-phase load. The efficient transmission and conversion of active / reactive power between the two-phase loads ensures the safe and reliable operation of the train. By designing an LMI controller to adjust the DC bus voltage and phase synchronization signal, the overall efficiency and stability of the power supply system are improved, providing strong support for the high-performance operation of the traction power supply network.

[0049] (2) Multi-objective collaborative optimization: This invention designs an LMI controller to simultaneously process stability P and tracking accuracy K r , and interference immunity γ. Energy mutations are modeled using Dd(t), and H∞ constraints γ suppress their impact on DC voltage. The dynamic robustness of K and the static accuracy of Kr are solved uniformly within a convex optimization framework, overcoming the inherent contradiction between rapidity, stability, and accuracy in traditional amplitude and phase control. Its gain matrix is ​​essentially the optimal solution under multi-objective constraints, enabling true adaptive control in the highly disturbed and nonlinear conditions of high-speed rail traction networks. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 Flowchart of a parallel multiple topology power quality management method based on location tracking LMI in an embodiment;

[0051] Figure 2 This is the main circuit diagram of the train in the embodiment;

[0052] Figure 3 The simulink circuit diagram of the HAPF in the embodiment;

[0053] Figure 4 : is a current waveform diagram of the traction grid side in the embodiment;

[0054] Figure 5 3. The figure shows the comparison of the 1st to 100th harmonic components of the traction network side current before and after RPC and HAPF filtering under four working conditions when there is a locomotive on each of the α side and the β side in the embodiment;

[0055] Figure 6 : is the FFT diagram of the traction network current before and after HAPF+lmi modulation when there are two locomotives on the α side and one locomotive on the β side pulling simultaneously in the embodiment;

[0056] Figure 7 3. The figure shows the comparison of the 1st to 100th harmonic components of the traction network side current before and after RPC and HAPF filtering under four working conditions when there are two locomotives on the α side and the β side in the embodiment;

[0057] Figure 8 Comparison of harmonic components 1-100th of the traction network side current after RPC and HAPF filtering under four working conditions with one locomotive on the α side and two locomotives on the β side

[0058] Figure 9 The following is a comparison of the 1st to 100th harmonic components of the traction network side current before and after RPC and HAPF filtering under four working conditions when there are two locomotives on the α side and one locomotive on the β side;

[0059] Figure 10 Schematic diagram of the harmonic content of the traction network side current under four working conditions before and after HAPF+LMI modulation when there is one locomotive on the α side and one locomotive on the β side;

[0060] Figure 11 Schematic diagram of the harmonic content of the traction grid current under four working conditions before and after HAPF+LMI modulation when there are two locomotives on the α side and one locomotive on the β side;

[0061] Figure 12 Schematic diagram of an electronic device in an embodiment. DETAILED DESCRIPTION

[0062] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0063] Example 1

[0064] To address the problems of harmonic amplification and excessive negative sequence imbalance in the aforementioned existing technologies, this embodiment provides a parallel multiple topology power quality management method based on position tracking LMI. By building a self-built regenerative braking model for the traction power supply system, a richer range of train operating conditions is obtained. The harmonics and negative sequence problems caused by locomotive traction braking on the grid side under various operating conditions are analyzed in detail. Harmonic control is performed using HAPF from a multi-operating condition perspective, which is more in line with the engineering practice of the traction power supply system.

[0065] In this method, the system power quality issues are first analyzed; then an engineering model including the traction power supply system and related key equipment is built; a quadruple railway power conditioner (RPC) model based on the LMI algorithm is designed; an EMU operation model is constructed and multiple operating conditions are designed; an adaptive adjustment strategy for the hybrid active power filter (HAPF) parameters is developed; and finally, the comprehensive system management effect is verified through multi-operating condition simulation.

[0066] See also Figure 1 , this method comprises the following steps:

[0067] Step S1: Analyze the power quality issues of the system.

[0068] As a key component of the traction power supply network, the traction transformer primarily performs voltage regulation and energy distribution. In railway power supply systems, the power system transmits three-phase AC power, while traction equipment such as EMUs require single-phase AC power to operate. The traction transformer acts as an "energy translator," converting three-phase AC power into single-phase AC power, enabling the energy to be transmitted to the EMUs in a suitable form. The operating parameters of the traction power supply model are shown in Table 1.

[0069] Table 1 Traction power supply system operating parameters

[0070]

[0071] Step S2: Build an engineering model including the traction power supply system and related key equipment.

[0072] Step S3: Innovatively design a quadruple railway power conditioner (RPC) model based on the LMI algorithm.

[0073] By introducing equipment such as the Railway Power Conditioner (RPC), optimized control of the traction power supply system is achieved. In practice, the RPC is connected in parallel to the traction power supply network, with each converter independently responsible for compensation within its corresponding power supply area. During system operation, each traction line is equivalent to a single-phase load. Efficient transmission and conversion of active and reactive power between the two-phase loads ensures safe and reliable train operation. Furthermore, this solution significantly improves the overall efficiency and stability of the power supply system, providing strong support for the high-performance operation of the traction power supply network.

[0074] The steady-state mathematical model of the single-side voltage source converter of the railway power conditioner RPC can be expressed as:

[0075]

[0076] Set the detected load current of the two arms to i αr 、i βr , then:

[0077]

[0078] In formula 3-2, I αrf and I βrf is the fundamental current amplitude, I αrn and I βrn is the nth harmonic current amplitude, θ α and θ βis the phase difference, which is positive when the load is capacitive and negative when the load is inductive. αn ,θ βn is the initial phase on both sides of the nth harmonic. Combining the trigonometric formula, we can expand 2-2 to obtain:

[0079]

[0080] The load current i of the α and β arms is deduced from the principle of phase detection method. αrp and i βrp , further simplifying it, we can get:

[0081]

[0082] The compensated bilateral traction current is:

[0083]

[0084] Among them, I′ p It represents the active current amplitude after active power transfer balance, ω is the angular frequency, and t represents time.

[0085] Therefore, the total compensation current instruction of the RPC system is:

[0086] In actual rail transit control systems, there are usually some interference factors that are difficult to avoid. In order to meet the stability and robustness of the system, the control strategy adopted by RPC amplitude and phase control is based on the LMI algorithm control of the position tracking system. Its characteristics are:

[0087] Optimizing the RPC amplitude and phase control to an LMI-based algorithm design can realize the control algorithm design of position tracking.

[0088] Its state equation can be expressed as:

[0089] Where: x(t)∈R n is the system state vector; u(t)∈R m is the control input; d(t) is the external disturbance; y(t) is the output (including the position tracking signal); A, B, C, D are the system parameter matrices.

[0090] Position tracking accuracy: Make the output y(t) accurately track the reference signal r(t), that is, lim t→∞ (y(t)-r(t))=0

[0091] Anti-interference: Suppresses the impact of external disturbance d(t) on tracking performance.

[0092] Robust stability: Keeping the closed-loop system stable under parameter perturbations or input constraints.

[0093] State feedback controller design: The controller form is: u(t)=Kx(t)+K r r(t)

[0094] Where K is the feedback gain matrix, K r is the feedforward gain matrix.

[0095] Design LMI: Through Lyapunov function V(x) = x T Px design LMI ensures system stability:

[0096]

[0097] The H∞ performance index is defined as:

[0098]

[0099] It is used to suppress the influence of disturbances, where γ is the disturbance suppression level.

[0100] Solve LMI to get the gain matrices K and K r .

[0101] Error definition: Tracking error e(t) = y(t) - r(t). The error dynamics are incorporated into the system equation through state expansion:

[0102] From u(t)=Kx+K r The closed-loop system equation becomes:

[0103] The LMI constraint is used to ensure that the eigenvalues ​​of the closed-loop system matrix A+BK are all located in the left half complex plane, thereby achieving asymptotic tracking and ensuring the stability of the closed-loop system.

[0104] In this embodiment, the definitions of some abstract symbols are shown in Table 2:

[0105] Table 2 Definition of abstract symbols

[0106]

[0107] Specifically, the steps for implementing LMI-based amplitude and phase control are as follows:

[0108] Step S301: Establish a state space model matching the Simulink structure and construct parameter matrices A, B, C, and D:

[0109]

[0110]

[0111] Among them, the four rows of A represent the dynamics of active current, reactive current, voltage error, and integral link (corresponding to 1 / Period of Mean module). B, C, and D represent the control input matrix and output matrix (U dc and θ), the feedforward matrix.

[0112] Step S302: Design LMI constraints.

[0113] Including stability constraints and H∞ performance constraints.

[0114] The stability constraints are:

[0115]

[0116] The H∞ performance constraint is:

[0117]

[0118] The feedback gain K is obtained by solving the LMI system.

[0119] Step S303: feedforward compensation design to improve tracking performance.

[0120] The feedforward gain K is calculated by the following formula r , so that y(t) accurately tracks r(t):

[0121] K r =(C[-(A+BK)] -1 B) -1

[0122] Step S304: construct an LMI controller.

[0123] Input: state vector x = [Δi p ,Δi q ,∫U dc ,ΔU dc ]. Where Δi p is the active current tracking error, Δi q is the reactive current tracking error, which reflects the power control accuracy.

[0124] Output: Modulation signal u=[v α ;v β ]. Where v α 、v β is the modulation voltage instruction in the α and β coordinate systems.

[0125] Implementation formula: u(t)=Kx(t)+K r r(t).

[0126] Step S305: Anti-disturbance verification.

[0127] The tests were conducted under three disturbance types: train regenerative braking, grid voltage drop (20%), and load step (1MW to 5MW). Under train regenerative braking, the test index is U dc <±5%, with the LMI control objective ensuring H∞ performance with a γ constraint. Under grid voltage drops, the test indicator is phase synchronization recovery time <10ns, with the LMI control objective ensuring stability in the left half plane of the eigenvalue. Under load steps, the test indicator is dynamic response time <15ms, with the LMI control objective optimizing the closed-loop poles.

[0128] By designing the LMI controller, it is possible to simultaneously handle stability (P>0), tracking accuracy (K r ), immunity (γ), energy mutation is modeled by Dd(t), and H∞ constraint γ suppresses its effect on U dc In order to eliminate the influence of the system parameters, the mean calculation module is retained, but the integral control is replaced by LMI, which improves the dynamic response speed. When the system parameters are perturbed, such as the filter inductance L±20%, the LMI solution set remains stable, avoiding the risk of loss of control.

[0129] Step S4: Construct an EMU operation model and design multiple operating conditions.

[0130] The main circuit of the train usually adopts a bidirectional four-quadrant converter structure, which can be simplified by an equivalent model. The equation is:

[0131]

[0132] in is the voltage phasor on the low voltage side, is the fundamental current phasor on the low voltage side, This is the fundamental phasor of the PWM modulated voltage. The EMU utilizes pulse width modulation technology, combined with a dual closed-loop proportional-integral control mechanism for voltage and current, to precisely regulate the phase, ensuring that the AC side meets the specified power factor standard. The voltage loop adjusts the amplitude of the modulated wave signal, combined with the current loop's dynamic phase adjustment to ultimately maintain the stability of the intermediate DC bus voltage.

[0133] Combined with the locomotive model and traction power supply system, various locomotive operating conditions are designed to perform grid-side negative sequence and harmonic analysis. For operating condition descriptions, refer to Table 3.

[0134] Table 3 Working conditions description

[0135]

[0136] Step S5: Developing a hybrid active power filter (HAPF) parameter adaptation strategy.

[0137] This embodiment adopts a power quality control method with a parallel multiple RPC topology structure, where the HAPF is composed of a modular combination of a passive power filter (PPF) and an active power filter (APF). Figure 3 , is the Simulink diagram of HAPF, which is used to suppress harmonics in the traction system and improve the power quality. Although the comprehensive performance of the passive filter is not as good as that of the active filter, it is effective in eliminating fixed-order harmonics. The specific design adopts a fixed single-resonance filter in parallel with a wide-band attenuation module, and selective filtering is achieved by matching the inductor and capacitor parameters corresponding to the 5th, 7th, and 11th harmonics. The additional high-pass network is constructed with a resistor-capacitor combination structure, focusing on weakening the fast harmonic components generated by high-frequency switching disturbances, further improving the system's harmonic control capabilities. From the circuit foundation, it can be seen that the nth-order PPF at frequency ω n = ω1 when the impedance Z fn for:

[0138] Among them, R n represents the nth order passive filter resistance, ω a Represents the frequency of the passive filter of order a (a is a positive integer), ω n Indicates the n-th PPF frequency, L n Indicates the n-th PPF inductance, C n Indicates the no-PPF capacitor of n times;

[0139] The capacitive reactive power compensated by the DC side capacitor of the active filter APF is:

[0140] ΔE(t)=Sk

[0141]

[0142] Among them, ΔE(t) represents the change value of the capacitance within one cycle, S represents the compensation size, k represents the transformation ratio, C represents the DC side capacitance, and ΔU m Indicates the voltage fluctuation range, U * m Indicates the voltage regulation value. The equivalent impedance of the output filter capacitor is

[0143] This embodiment adopts the i based on instantaneous reactive power theory. p -i q Improvement method. i p 、i q Corresponding to active and reactive currents, we have the definition Then we have:

[0144]

[0145] To address the harmonic problem in the above working conditions, HAPF filter is used for filtering. The parameter settings are shown in Table 4:

[0146] Table 4 HAPF filter filtering parameters

[0147]

[0148] Step S6: Verify the comprehensive treatment effect of the system through multi-operating condition simulation.

[0149] In the experiment, the power of the two traction transformers in this embodiment is 8×10 6 VA and 12.5×10 6 VA. This traction power supply system converts the input voltage into a voltage suitable for the load through two transformers with different turns ratios, and transmits the electrical energy to the load through V / V wiring. This system design can effectively meet the power supply needs of traction motors in rail transportation. Figure 2 This is the main circuit diagram of the train.

[0150] See also Figure 4 The grid-side current waveform of this embodiment from 0s to 1s is shown. The three-phase current fluctuates when the locomotive operating conditions change. Figure 5 It can be seen that the current harmonics on the traction grid side have decreased at 0-10 and 50-60 times, see Figure 6 It can be seen that the THD of the traction grid current harmonics is significantly reduced before and after modulation, from 5.49% to 2.51%. Figure 7 It can be seen that after filtering by RPC and HAPF, the traction network current harmonics are significantly reduced in low-order harmonics and harmonics around 50-60 and 90-100. Figure 8 It can be seen that after filtering by RPC and HAPF, the current harmonics on the traction grid side have significantly decreased in both low-order harmonics and 50-60th harmonics. Figure 9 It can be seen that after RPC and HAPF filtering, the current harmonics on the traction grid side have decreased in both low-order harmonics and 50-60 harmonics, see Figure 10 The figure shows the relationship between harmonic content and harmonic order of traction grid current under different working conditions. It can be seen from the figure that after HAPF+LMI modulation, the 0-50 harmonic content of each working condition is reduced. Figure 11 The figure shows the relationship between the harmonic content and harmonic order of the traction grid current under different working conditions. It can be seen from the figure that after HAPF+LMI modulation, the 0-10th and 50-60th harmonic contents are significantly reduced.

[0151] In summary, this embodiment achieves comprehensive compensation for active power, reactive power, and harmonics by connecting four RPCs in parallel to the traction power supply system, employing a position-tracking LMI amplitude-phase control strategy, and combining a hybrid energy storage device consisting of lithium batteries and flywheels. This simultaneously stores and recycles electrical energy, significantly improving energy efficiency. Targeted to the actual locomotive circuit, the system employs PWM control technology and a dual closed-loop PI control strategy to precisely adjust the phase, ensuring stable and efficient system operation.

[0152] Example 2

[0153] Based on Example 1, this embodiment provides an electronic device, including: one or more processors and a memory, wherein the memory stores one or more programs, and the one or more programs include instructions for executing the parallel multiple topology power quality management method based on location tracking LMI as described in Example 1.

[0154] like Figure 12 As mentioned above, at the hardware level, the electronic device includes a processor, an internal bus, a network interface, a memory and a non-volatile memory, and may also include other hardware required for the business. The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it to achieve the above Figure 1 Of course, in addition to software implementation, the present invention does not exclude other implementation methods, such as logic devices or a combination of software and hardware, etc., that is, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic devices.

[0155] Memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

[0156] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

[0157] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A parallel multiple topology power quality management method based on location tracking LMI, characterized in that: The steps include: For the locomotive traction power supply system, an RPC amplitude and phase control model is established based on the parallel multiple RPC topology structure; By constructing a state-space model, designing LMI constraints and feedforward compensation, an LMI controller is constructed with d-axis modulation voltage and q-axis modulation voltage as input and DC bus voltage and phase synchronization signal as output to achieve stable progressive position tracking.

2. The method for managing power quality of a parallel multiple topology based on location tracking LMI according to claim 1 is characterized in that: The construction process of the RPC amplitude-phase control model includes the following steps: Establish the steady-state mathematical model of the single-side voltage source converter of the railway power conditioner RPC; Calculate the detected load current of the two arms; Calculate the compensated bilateral traction current; Get the total compensation current of the RPC system.

3. The method for managing power quality of parallel multiple topology based on location tracking LMI according to claim 2 is characterized in that: The steady-state mathematical model is: Among them, i d 、i q 、u dc are the d-axis and q-axis currents and DC voltages of the single-side voltage source converter of the railway power conditioner RPC, R, L, and C are resistance, inductance, and capacitance, respectively. ω is the angular frequency, and k c is the voltage u c The amplitude adjustment coefficient, δ is the inverter output u s The phase angle, U s is the reference vector u s Valid values.

4. The method for managing power quality of a parallel multiple topology based on location tracking LMI according to claim 2 is characterized in that: The load current of the two arms is: Among them, i αr 、i βr are the load currents of the two arms, I αrf and I βrf is the fundamental current amplitude, I αrn and I βrn is the nth harmonic current amplitude, θ α and θ β is the phase difference, which is positive when the load is capacitive and negative when the load is inductive. αn ,θ βn is the initial phase on both sides of the nth harmonic, ω is the angular frequency, and t represents time.

5. The method for managing power quality of parallel multiple topology based on location tracking LMI according to claim 2 is characterized in that: The compensated bilateral traction current is: Among them, i′ α , i′ β They are the compensated bilateral traction currents, I′ p It represents the active current amplitude after active power transfer balance, ω is the angular frequency, and t represents time.

6. The method for managing power quality in a parallel multiple topology based on location tracking LMI according to claim 2, characterized in that: The total compensation current of the RPC system is: in, are the compensation currents on both sides of the RPC system, i′ α , i′ β are the compensated bilateral traction currents, i αr 、i βr are the load currents of the two arms respectively.

7. The method for managing power quality in a parallel multiple topology based on location tracking LMI according to claim 1, characterized in that: The state space model is modeled as: Where x(t)∈R n is the system state vector, including d-axis current, q-axis current, DC voltage error and DC voltage integral compensation term; u(t)∈R m is the control input, including the d-axis modulation voltage and the q-axis modulation voltage, d(t) is the external disturbance, including the train power step, grid voltage amplitude change and braking feedback power; y(t) is the output, including the DC link voltage and the grid phase angle obtained by position tracking; A, B, C, D are the system parameter matrices.

8. The method for managing power quality in a parallel multiple topology based on location tracking LMI according to claim 7 is characterized in that: The LMI controller is in the form of: u(t)=Kx(t)+K r r(t) Among them, K is the feedback gain matrix, K r is the feedforward gain matrix, r(t) is the reference signal, including the set voltage and ideal phase.

9. The method for managing power quality of parallel multiple topology based on location tracking LMI according to claim 8, characterized in that: The feedback gain matrix is ​​solved under stability constraints and H∞ performance constraints, and the feedforward gain matrix is ​​solved by feedforward compensation, wherein, The stability constraints are: Where T represents transpose, P is a symmetric positive definite matrix; The H∞ performance constraint is: Where γ is the disturbance suppression level, I is the unit matrix, The feedforward gain matrix is ​​solved using the following formula: K r =(C[-(A+BK)] -1 B) -1 Where, () -1 Indicates inversion.

10. An electronic device, characterized in that: It includes one or more processors, a memory and one or more programs stored in the memory, and the one or more programs include instructions for executing the parallel multiple topology power quality management method based on location tracking LMI as described in any one of claims 1-9.

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