Rail alternating current power supply energy control method and system based on LCL and RPC

Abstract

The invention discloses a rail alternating current power supply energy control method and system based on LCL and RPC, and can effectively solve the problem that harmonic suppression is difficult to effectively compensate for harmonic waves under the condition that the working conditions of a high-speed train are complex and changeable in the prior art. According to the specific technical scheme, a harmonic change rule and a power compensation state of changes of a harmonic servo-motor train unit and a traction network are obtained through analysis; an LCL type filter is constructed in the multiple RPC structure according to the rule, and the resonant frequency is obtained; receiving production data of a user according to the operation state of the traction power supply system model, and designing the operation state into six types of locomotive working conditions; simulating the locomotive harmonic source models under different working conditions through an LCL type filter to obtain simulation results; according to a simulation result, a parameter algorithm of the LCL type filter is experimented to obtain target parameters, and then the target parameters are embedded into a locomotive harmonic source model; and performing harmonic and compensation power analysis on the traction power supply system model according to the target parameters to obtain a result, and constructing a visual system.

Description

Technical Field

[0001] The present invention relates to the field of high-speed railway electric power technology, and in particular to a rail transit power supply energy control method and system based on LCL and RPC. Background Art

[0002] EMUs are the main traction loads of high-speed railways. During their operation, they generate a large amount of harmonic currents, which seriously affect the power quality of the power grid. Harmonic currents not only cause energy waste, but also have adverse effects on other power equipment and communication systems, and even cause harmonic resonance, threatening the safe and reliable operation of trains. At the same time, they also cause energy waste when the trains brake.

[0003] At present, there are many studies on harmonic current and energy compensation calculation at home and abroad. The simulation program can roughly simulate the actual operation status of the train through the construction and architecture of various electrical components. It can basically reflect the power quality-related data such as harmonic current, power and imbalance during the operation process. However, it has certain imperfections and lacks a complete modeling of all components and equipment of the real train.

[0004] In the prior art, TSC technology is used in RPC devices. Its working principle is simple and the effect is relatively good. However, the working conditions of high-speed trains are very complex and changeable, which makes the harmonic dynamic characteristics of trains very changeable. In addition, the rapid change of harmonic injection position leads to the change of harmonic transmission characteristics of the system. Therefore, it is difficult for general harmonic control systems to effectively compensate for harmonics. Summary of the invention

[0005] The embodiment of the present invention provides a rail transit power supply energy control method and system based on LCL and RPC, which can solve the problem in the prior art that harmonic control is difficult to effectively compensate for harmonics when the working conditions of high-speed trains are complex and changeable. The technical solution is as follows:

[0006] According to a first aspect of an embodiment of the present invention, a method for controlling rail transit power supply energy based on LCL and RPC is provided, the method comprising:

[0007] Analyze the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change;

[0008] According to the harmonic variation law, an LCL filter is constructed in the multiplexed RPC structure, and the resonant frequency is obtained;

[0009] According to the operating state of the traction power supply system model, receiving the production data of the user, and designing the operating state into six types of locomotive operating conditions;

[0010] The locomotive harmonic source model under the six types of locomotive operating conditions is simulated by the LCL filter to obtain simulation results;

[0011] Experimenting on the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, obtaining target parameters through a variable neighborhood search algorithm, verifying the rationality of the target parameters, and if reasonable, embedding the target parameters into the locomotive harmonic source model;

[0012] Performing harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results;

[0013] A visualization system is constructed for the harmonics and compensation power results and the power compensation status under the different locomotive operating conditions.

[0014] The rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention first analyzes the grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtains the harmonic change law and power compensation state of the harmonics changing with the EMU and the traction network; constructs an LCL filter in a multiplexed RPC structure according to the harmonic change law, and obtains the resonant frequency; receives the production data of the user according to the operating state of the traction power supply system model, and designs the operating state as six types of locomotive operating conditions; simulates the locomotive harmonic source model under the six types of locomotive operating conditions through the LCL filter to obtain simulation results; then experiments are conducted on the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, and the target parameters are obtained through a variable neighborhood search algorithm to verify the rationality of the target parameters. If reasonable, the target parameters are embedded in the locomotive harmonic source model; harmonic and compensation power analysis is performed on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain harmonic and compensation power results; finally, a visualization system is constructed for the harmonic and compensation power results and power compensation states under different locomotive operating conditions. The method of the present invention can effectively analyze and control the negative sequence current and harmonic wave problems generated during the operation of high-speed railways, reduce the harm of negative sequence current to the traction power supply system and EMU equipment, extend the service life of the equipment, and reduce maintenance costs; reduce the impact of harmonics on the public power grid and train electrical equipment, reduce power loss, improve power utilization, and save energy; improve the power supply quality and reliability of the traction power supply system, reduce power supply failures, and ensure the normal operation of the high-speed railway.

[0015] As a further solution of the present invention: the problem of grid harmonics and power compensation of the EMU and traction network of the traction power supply system model is analyzed to obtain the harmonic change law and power compensation state of the harmonics as the EMU and traction network change, which specifically includes the following steps:

[0016] When the working condition of the EMU changes, the corresponding harmonic characteristics are obtained to obtain the harmonic change law;

[0017] The active and reactive power compensation of the grid side by the RPC device currently equipped on the EMU is obtained to obtain the power compensation state.

[0018] As a further solution of the present invention: constructing an LCL filter in a multiplexed RPC structure according to the harmonic variation law and obtaining the resonant frequency specifically includes:

[0019] According to the law of harmonic change, a harmonic control solution combined with the RPC device is adopted, and an LCL filter is installed inside the RPC device to perform frequency scanning analysis to obtain the impedance and resonant frequency of the LCL filter; the impedance of the LCL filter includes the impedance of a single-tuned filter and the impedance of a passive damping method LCL filter.

[0020] As a further solution of the present invention: the impedance of the single tuned filter is calculated by the following formula:

[0021]

[0022] w=2πf

[0023]

[0024] Among them, Z s The impedance of a single tuned filter, R s is the resistance of the single tuned filter, w is the angular frequency, L is the inductance of the single tuned filter, C s is the capacitance of the single tuned filter, j is the imaginary part;

[0025] The impedance of the passive damping method LCL filter is calculated by the following formula:

[0026]

[0027] X1=R+jwL1

[0028]

[0029] X3=jwL2

[0030] Among them, Z lcl is the impedance of the passive damping method LCL filter, L1 is the first capacitor of the LCL filter, L2 is the second capacitor of the LCL filter, R is the resistance of the LCL filter, C is the capacitance of the LCL filter, X1 is the impedance of the resistor in series with the inductor L1, X2 is the impedance of the capacitor C in the LCL filter, X3 is the impedance of the inductor L2, and w is the angular frequency;

[0031] The resonant frequency is calculated by the following formula:

[0032]

[0033] Among them, f res is the resonant frequency, L1 is the first capacitor of the LCL filter, L2 is the second capacitor of the LCL filter, and C is the capacitance of the LCL filter.

[0034] As a further solution of the present invention: the production data includes: the three-phase system voltage is 220kV, the traction substation capacity is 40MW, the traction substation transformer ratio is 220:27.5, the AT capacity is 40MW, and the total simulation time is 2s; the traction substation wiring mode is V / v, connected to the three-phase side and the ground respectively, the traction network is AT power supply, the traction network voltage is 27.5kV, the access time under the regenerative braking condition is 1.00s, and the voltage is rated 3000V;

[0035] The six types of locomotive operating conditions include: operating condition 1 is single left-side traction and right-side braking; operating condition 2 is double traction, with both power supply arms on both sides in traction operation; operating condition 3 is left-side braking and right-side traction; operating condition 4 is double-row braking, with both power supply arms on both sides in braking; operating condition 5 is single traction on the left side and no car on the right side; operating condition 6 is single braking on the left side and no car on the right side.

[0036] As a further solution of the present invention: the locomotive harmonic source model under the six types of locomotive working conditions is simulated by the LCL filter to obtain simulation results, which specifically includes the following steps:

[0037] The CRH2 traction power supply simulation model and the RPC energy compensation device model are used to simulate the locomotive grid-side current, voltage and phase relationship under six types of locomotive operating conditions. The total harmonic content THD of the grid-side current is analyzed through the simulated structure and the double FFT harmonic analysis method of the simulation system.

[0038] As a further solution of the present invention: performing harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results specifically includes the following steps:

[0039] By controlling the simulation of the locomotive running state, the stable harmonic at 0.08s is taken, the harmonic content of each locomotive working condition is horizontally compared, the harmonic data is analyzed, the compensation power, negative sequence imbalance, power factor, etc. are calculated, and the harmonic and compensation power results are obtained;

[0040] The LCL filter parameter system is used for filtering. The parameter setting is calculated and assigned by the VNS algorithm. The external single-tuned filter uses ordinary parameters, which are C s =1.014uF, L1=18.4Mh, R=80Ω.

[0041] As a further solution of the present invention: the harmonics and compensation power results are calculated by the following calculation equation:

[0042]

[0043]

[0044] Among them, the three-phase voltage on the high-voltage side of the traction transformer is u A 、u B 、u C , the secondary traction conductor voltage is u α and u β , assuming phase A is the reference voltage, then the reference vector is u A (t) = sin(ωt), the load current of the two arms is i α_l 、i β_l , I α_lf with I β_lf is the fundamental amplitude, I α_lh with I β_lh is the hth harmonic amplitude, θ α and θ β is the phase difference, inductive is negative, capacitive is positive, θ α_h ,θ β_h is the initial phase angle of the corresponding harmonics on both sides of α and β, I′ p , I' α_p , I' β_p is the active current amplitude after active power transfer balance, i' α 、i' β To compensate the current on both sides, is the current compensation signal on both sides, P is the active power, Q is the reactive power, U α and U β is the voltage amplitude of the power supply arm, and is the current reference amplitude, ψ α and ψ β is the phase angle of the corresponding power supply arm.

[0045] As a further solution of the present invention: the visualization system for the harmonics and compensation power results and the power compensation status under the different locomotive working conditions includes:

[0046] The parameter algorithm is combined with the locomotive harmonic source model through a GUI, so that the target parameters and the power compensation state obtained by the parameter algorithm are given to the locomotive harmonic source model through an interface to build a visualization system.

[0047] On this basis, a sub-interface is set up to calculate energy compensation using theoretical algorithms. The data of the simulation results can be input into the sub-interface to obtain the corresponding theoretical compensation results for users to compare and understand in the main interface.

[0048] This application reflects the specific figures of active and reactive compensation power in the interface through the layout of interface design, and visualizes the voltage and current imbalance and grid-side current in the interface. Users can intuitively see the three-phase current waveform of the traction network and understand the real-time changes of power factor and voltage imbalance as the train runs in simulation, without relying on separate experimental operations.

[0049] According to a second aspect of an embodiment of the present invention, a rail transit power supply energy control system based on LCL and RPC is provided, comprising: a first analysis module, a construction module, a design module, a simulation module, a calculation module, a second analysis module, and a display module;

[0050] The first analysis module is used to analyze the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change;

[0051] The construction module is used to construct an LCL filter in the multiplexed RPC structure according to the harmonic change rule and obtain the resonant frequency;

[0052] The design module is used to receive the production data of the user according to the operating state of the traction power supply system model, and design the operating state into six types of locomotive operating conditions;

[0053] The simulation module is used to simulate the locomotive harmonic source model under the six types of locomotive working conditions through the LCL filter to obtain simulation results;

[0054] The calculation module is used to experiment the parameter algorithm of the LCL filter according to the simulation result and the resonant frequency, obtain the target parameter by a variable neighborhood search algorithm, verify the rationality of the target parameter, and if it is reasonable, embed the target parameter into the locomotive harmonic source model;

[0055] The second analysis module is used to perform harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results;

[0056] The display module is used to construct a visualization system for the harmonics and compensation power results and the power compensation status under the different locomotive operating conditions.

[0057] The rail transit power supply energy control system based on LCL and RPC provided by the embodiment of the present invention includes a first analysis module, a construction module, a design module, a simulation module, a calculation module, a second analysis module, and a display module; the first analysis module analyzes the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtains the harmonic change law and power compensation state of the harmonics changing with the EMU and the traction network; the construction module constructs an LCL filter in a multiple RPC structure according to the harmonic change law, and obtains the resonant frequency; the design module receives the user's production data according to the operating state of the traction power supply system model, and designs the operating state Six types of locomotive working conditions; the simulation module simulates the locomotive harmonic source model under six types of locomotive working conditions through the LCL filter to obtain the simulation results; the calculation module experiments the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, obtains the target parameters through the variable neighborhood search algorithm, verifies the rationality of the target parameters, and if reasonable, embeds the target parameters into the locomotive harmonic source model; the second analysis module performs harmonic and compensation power analysis on different locomotive working conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results; the display module constructs a visualization system for the harmonic and compensation power results under different locomotive working conditions and the power compensation state. The system of the present invention can effectively analyze and control the negative sequence current and harmonic wave problems generated during the operation of high-speed railways, reduce the harm of negative sequence current to the traction power supply system and EMU equipment, extend the service life of the equipment, and reduce the maintenance cost; reduce the impact of harmonics on the public power grid and train electrical equipment, reduce power loss, improve power utilization, and save energy; improve the power supply quality and reliability of the traction power supply system, reduce power supply failures, and ensure the normal operation of the high-speed railway.

[0058] According to a third aspect of an embodiment of the present invention, a rail transit power supply energy control device based on LCL and RPC is provided, and the rail transit power supply energy control device based on LCL and RPC includes a processor and a memory, and the memory stores at least one computer instruction, and the instruction is loaded and executed by the processor to implement the steps performed in any of the above-mentioned rail transit power supply energy control methods based on LCL and RPC.

[0059] According to a fourth aspect of an embodiment of the present invention, a computer-readable storage medium is provided, wherein at least one computer instruction is stored in the storage medium, and the instruction is loaded and executed by a processor to implement the steps performed in any of the above-mentioned methods for controlling rail transit power supply energy based on LCL and RPC.

[0060] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0062] Figure 1 A flow chart of a rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0063] Figure 2 The grid-side three-phase harmonic distribution of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0064] Figure 3 An equivalent circuit diagram of a rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention with a filter added;

[0065] Figure 4 The grid-side voltage harmonic level under traction conditions of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0066] Figure 5 Current harmonic distribution under dual traction conditions of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0067] Figure 6 Current harmonic distribution under regenerative braking conditions of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0068] Figure 7 The grid-side voltage harmonic level under braking conditions of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0069] Figure 8 An algorithm flow chart of the VNS algorithm for automatically optimizing LCL filter parameters in the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0070] Fig. 9 The multi-operating-state current harmonic content rate of the traction network side of the rail transit power supply energy control method based on LCL and RPC provided in the embodiment of the present invention;

[0071] Fig.10 The voltage harmonic content rate of multiple working conditions on the traction network side of the rail transit power supply energy control method based on LCL and RPC provided in the embodiment of the present invention;

[0072] Fig.11 Current harmonic distribution over time of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0073] Fig.12 Voltage harmonic distribution over time of the rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0074] Fig.13 A data analysis diagram of system construction of a rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0075] Fig.14 A GUI interface diagram of a rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0076] Fig.15 A GUI interface diagram of a rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0077] Fig.16 A GUI interface diagram of a rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention;

[0078] Fig.17 The result interface of common optimization compensation in the GUI of the rail transit power supply energy control method based on LCL and RPC provided in the embodiment of the present invention;

[0079] Fig.18 Description of the RPC energy compensation principle in the rail transit power supply energy control method GUI based on LCL and RPC provided in an embodiment of the present invention;

[0080] Fig.19 A structural diagram of a rail transit power supply energy control system based on LCL and RPC provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0081] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of systems and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0082] The embodiment of the present invention provides a rail transit power supply energy control method based on LCL and RPC, such as Figure 1 As shown, the following steps are included:

[0083] Step 101: Analyze the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model to obtain the harmonic change law and power compensation status of the harmonics as the EMU and the traction network change.

[0084] Generally speaking, locomotives are the main source of harmonics, and the traction network is a complex power supply network composed of multiple irregular conductors such as contact wires, load-bearing cables, positive feed lines, rails, etc. There are large distributed capacitance and inductance between the power supply lines. When the distributed capacitance and inductance match the impedance of other equipment in the system at a certain frequency, a system resonance point will be formed, and the RPC will also resonate when performing energy compensation. When the harmonic current generated during the operation of the EMU is basically consistent with the resonance point, high-frequency resonance will occur, causing unstable operation of the train and energy loss.

[0085] In one embodiment, the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model are analyzed to obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change, which specifically includes the following steps:

[0086] When the working condition of the EMU changes, the corresponding harmonic characteristics are obtained to obtain the harmonic change law;

[0087] Obtain the active and reactive power compensation of the RPC device currently equipped on the EMU for the grid side and obtain the power compensation status.

[0088] Specifically, the present embodiment analyzes and obtains the power compensation state, which is in accordance with the industrial needs of users and is conducive to the subsequent construction of a visualization system for convenient and quick use by users.

[0089] according to Figure 2 Analysis shows that high-frequency harmonics are mainly distributed around the 53rd and 94th harmonics. In the double-row traction condition, the high-frequency harmonic current amplification phenomenon near the 90th harmonic is particularly obvious. This is because the converter carrier modulation signal is 90*50=4500HZ at this time, and the resonance formed by the similar frequency during operation. In the full-load traction and full-load regenerative braking conditions on both sides, the load current measurement content is most obviously different near the 8th harmonic. This phenomenon shows that when in the regenerative braking condition, the impact on the load current is greater. When the working conditions on both sides of the load are different, when in working conditions 1 and 3, according to the current harmonic distribution, it can be seen that when the α side is traction, the 52nd harmonic will be amplified, and in comparison, the β side traction has a lower harmonic content near the 50th. The above harmonic characteristics can serve as the basis for the subsequent study of the differences between different working conditions, and also prove the positive role of regenerative braking energy in energy compensation.

[0090] During the simulation operation, the harmonic fluctuations generated by harmonic impedance during filtering cannot be ignored. Therefore, when designing the harmonic control solution, this application comprehensively considers the influence of multiple aspects and multiple working conditions, and defines the filtering effect in combination with the harmonic standards of the power grid in Table 1.

[0091] Table 1 Harmonic standards for power grid

[0092]

[0093] Step 102: construct an LCL filter in the multiplexed RPC structure according to the harmonic variation rule, and obtain the resonant frequency.

[0094] Specifically, when the LCL filter is installed on the RPC and the single tuner is installed on the grid side for frequency scanning, the traction power supply system can be equivalent to the following: Figure 3 The equivalent circuit is shown.

[0095] In one embodiment, an LCL filter is constructed in a multiplexed RPC structure according to a harmonic variation rule, and a resonant frequency is obtained, specifically including:

[0096] According to the law of harmonic change, a harmonic control solution combined with the RPC device is adopted. The LCL filter is installed inside the RPC device for frequency scanning analysis to obtain the impedance and resonant frequency of the LCL filter; the impedance of the LCL filter includes the impedance of the single-tuned filter and the impedance of the passive damping method LCL filter.

[0097] In one embodiment, the impedance of a single tuned filter is calculated by the following formula:

[0098]

[0099] w=2πf

[0100]

[0101] Among them, Z s The impedance of a single tuned filter, R s is the resistance of the single tuned filter, w is the angular frequency, L is the inductance of the single tuned filter, C s is the capacitance of the single tuned filter, j is the imaginary part;

[0102] The impedance of the passive damping LCL filter is calculated by the following formula:

[0103]

[0104] X1=R+jwL1

[0105]

[0106] X3=jwL2

[0107] Among them, Z lcl is the impedance of the passive damping method LCL filter, L1 is the first capacitor of the LCL filter, L2 is the second capacitor of the LCL filter, R is the resistance of the LCL filter, C is the capacitance of the LCL filter, X1 is the impedance of the resistor in series with the inductor L1, X2 is the impedance of the capacitor C in the LCL filter, X3 is the impedance of the inductor L2, and w is the angular frequency;

[0108] The resonant frequency is calculated using the following formula:

[0109]

[0110] Among them, f res is the resonant frequency, L1 is the first capacitor of the LCL filter, L2 is the second capacitor of the LCL filter, and C is the capacitance of the LCL filter.

[0111] Step 103: Receive the production data of the user according to the operating status of the traction power supply system model, and design the operating status into six types of locomotive operating conditions.

[0112] In one embodiment, the production data includes: the three-phase system voltage is 220kV, the traction substation capacity is 40MW, the traction substation transformer ratio is 220:27.5, the AT capacity is 40MW, and the total simulation time is 2s; the traction substation wiring mode is V / v, connected to the three-phase side and the ground respectively, the traction network is powered by AT, the traction network voltage is 27.5kV, the access time under the regenerative braking condition is 1.00s, and the voltage is rated 3000V;

[0113] The six types of locomotive operating conditions include: operating condition 1 is single traction on the left side and braking on the right side; operating condition 2 is double traction, with both power supply arms on both sides in traction operation; operating condition 3 is braking on the left side and traction on the right side; operating condition 4 is double-row braking, with both power supply arms on both sides braking; operating condition 5 is single traction on the left side and no car on the right side; operating condition 6 is single braking on the left side and no car on the right side.

[0114] In general, considering the line loss on the low-voltage side of the traction network when the locomotive is running, the locomotive power supply voltage will be increased by 10% to compensate for the voltage level, that is, 25x(1+10%)=27.5kV. Combined with the equipment electrical parameters of a domestic traction substation, the simulation parameters are configured as shown in Table 2.

[0115] Table 2 Simulation parameter configuration table

[0116] System Parameters value Three-phase system voltage / kV 220 Traction substation capacity / MW 40 Transformer ratio of traction substation 220:27.5 RPC side voltage / kV 3.88 AT capacity MW 40 Simulation duration / s 2

[0117] The traction substation adopts V / v connection, that is, the primary side is connected to AB and BC phases, and the neutral point of the secondary side is grounded. The traction network is powered by AT. By setting the circuit breaker to open and close, the train passing is simulated. Ensure that the traction network voltage is at the 27.5kV level and the train runs normally in the traction power supply system.

[0118] Combining the locomotive model and traction power supply system, six locomotive operating conditions are designed to carry out negative sequence and harmonic analysis on the grid side. The operating condition description can be found in Table 3.

[0119] Table 3 Working Conditions

[0120] Working conditions Simulation time Working conditions Condition 1 0.2s-0.5s α traction-β braking, traction on the left, braking on the right Condition 2 0.5s-0.7s Double row traction Condition 3 0.7s-1.0s α braking-β traction, braking on the left, traction on the right Condition 4 1.0s-1.2s Double row brake Condition 5 1.2s-1.5s Left side towing, right side unloaded Condition 6 1.5s-2.0s Left side braked, right side unloaded

[0121] Step 104: simulate the locomotive harmonic source model under six types of locomotive operating conditions through an LCL filter to obtain simulation results.

[0122] In one embodiment, a locomotive harmonic source model under six types of locomotive operating conditions is simulated by an LCL filter to obtain simulation results, which specifically includes the following steps:

[0123] The CRH2 traction power supply simulation model and the RPC energy compensation device model are used to simulate the locomotive grid-side current, voltage and phase relationship under six types of locomotive operating conditions. The total harmonic content THD of the grid-side current is analyzed through the simulated structure and the double FFT harmonic analysis method of the simulation system.

[0124] Specifically, the CRH2 (CRH380AL) traction power supply simulation model and the RPC energy compensation device model are used to verify the correctness and adaptability of the model. The locomotive grid-side voltage and current and their phase relationship under traction conditions and regenerative braking conditions are simulated respectively. The double FFT harmonic analysis method is used to analyze the total harmonic content THD of the grid-side current and the harmonic content of the control voltage. Figure 4 , Figure 5 , Figure 6 , Figure 7 . Figure 5 , Figure 6 The current harmonic distribution and Figure 4 and Figure 7 The distribution trend of voltage harmonics of CRH2 EMU is basically the same. The higher harmonics are mainly distributed around 55th, which means that most of the resonance points near the system are around 55th, which leads to the amplification of voltage harmonics.

[0125] The harmonic distribution of the two different working conditions, traction and regenerative braking, has certain similarities. The low-order harmonics are mainly concentrated in odd-numbered orders, such as the lower 3rd, 5th, and 7th orders. During the operation of the locomotive, some nonlinear devices in the locomotive will generate harmonics, which will lead to the generation and distribution of harmonics. When the load is under rated conditions, the harmonic distortion rate is within the normal range. However, in the regenerative braking stage, the grid-side voltage is opposite to the current direction. At this time, the converter acts as an inverter and outputs negative power in the reverse direction. After verification, it can be found that the harmonic content and voltage level are consistent with the theoretical analysis results, and the model meets the requirements.

[0126] Step 105: Experiment on the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, obtain the target parameters through the variable neighborhood search algorithm, verify the rationality of the target parameters, and if reasonable, embed the target parameters into the locomotive harmonic source model.

[0127] Specifically, LCL filter is used to improve harmonics for harmonic problems, and parameter setting relies on variable neighborhood search algorithm (VNS) for intelligent calculation and assignment to simulation program. The full name of VNS intelligent algorithm is variable neighborhood search algorithm. Its algorithm flow chart is used in this method. Figure 8 As shown in Figure 2, the single-tuned filter is assigned with common parameters.

[0128] Common parameters of single tuned filter: C1=1.014uF; L1=18.4mh; R=80Ω.

[0129] The results show that the filtering scheme eliminates most of the harmonics, and the THDu of the traction network is reduced from 4.39% to 2.11%. Although most of the high-frequency components are filtered out after LCL filtering, the harmonic components of the 23rd and 25th harmonics are still prominent. Next, the filtering of the voltage waveform on the traction side is shown. Fig.10 . Fig. 9 It reflects the harmonic distribution under different working conditions. The main difference is that low-order harmonics are concentrated in 1-10th order, and high-order harmonics are concentrated in 50-60th order. It can be found that when in double braking condition, the distribution of harmonics is obviously different from other conditions.

[0130] The waveform results show that the voltage waveform is smoother and the harmonic content is lower after the filter is put into use. Next, the voltage level and harmonic situation on the traction network side are compared. Finally, the filtering results of all working conditions are summarized in Table 4 as follows:

[0131] Table 4 Summary of filtering results for all working conditions

[0132]

[0133]

[0134] It can be found from the table that the filtering efficiency of this scheme is better than the existing scheme without filtering, and the filtering efficiency also has good effect when the working conditions change. It can be seen that the filtering effect of this scheme is highly adaptable and has good application prospects in harmonic control in high voltage and high current situations. Step 106: According to the target parameters, the harmonic and compensation power analysis of different locomotive working conditions of the traction power supply system model is performed to obtain the harmonic and compensation power results.

[0135] In one embodiment, harmonic and compensation power analysis is performed on different locomotive operating conditions of the traction power supply system model according to target parameters to obtain harmonic and compensation power results, which specifically includes the following steps:

[0136] Through the simulation of the locomotive running state, the stable harmonic at 0.08s is taken, the harmonic content of each locomotive working condition is compared horizontally, the harmonic data is analyzed, the compensation power, negative sequence imbalance, power factor, etc. are calculated, and the harmonic and compensation power results are obtained;

[0137] The LCL filter parameter system is used for filtering. The parameter setting is calculated and assigned by the VNS algorithm. The external single-tuned filter uses ordinary parameters, which are C s =1.014uF, L1=18.4mh, R=80Ω.

[0138] In this embodiment, combined with the working conditions, by controlling the locomotive running state simulation, take working condition 1 as an example: α traction-β braking, left traction, right braking, the upward α power supply arm has a train passing, and the downward β power supply arm has a train braking. The generated current and voltage harmonic distribution can be referred to Fig.11 , Fig.12 It can be concluded that as the simulation time increases, the harmonics within the 10th order of current gradually decrease and tend to be stable. The number of high-frequency harmonics of voltage will also basically maintain a stable trend and will not fluctuate dramatically over time.

[0139] In order to describe the harmonic data under various working conditions more specifically, the stable harmonic at 0.08s is taken. Under all working conditions, the harmonic characteristics of the two-phase voltage side are generally the same as Figure 2 The harmonic distribution of the traction network coupled with the harmonic source of the locomotive is consistent, and the high-frequency harmonics under most working conditions are concentrated around 58. In the single-train braking condition, the high-frequency harmonic current near the 56-62 harmonics increases significantly. The biggest difference between the double-row traction condition and the double-row braking condition is the 4-11 harmonics, which is higher than the double traction condition during double braking, indicating that the braking condition has a stronger impact on the traction network. The above harmonic characteristics can lay the foundation for subsequent research on the differences between different working conditions, and the results are shown in Table 5.

[0140] Table 5 Harmonic characteristics comparison table

[0141]

[0142]

[0143] It can be seen from Table 5 that under the left-traction and right-braking condition, since the train state has just changed, the harmonic content at the time of connection is relatively large. Overall, it shows the characteristic of large harmonics during simultaneous traction and braking conditions. In particular, the left-traction and right-braking condition produces a slightly larger harmonic fluctuation, with a drop of 54.2%. There are also significant differences in the harmonic content rate. For example, when the α power supply arm is in the traction condition, the harmonic content is significantly higher than other conditions, and the harmonic content is highest during double-row braking. The experimental results show that the harmonic content under various conditions has a good degree of distinction, and when the braking condition is dominant, the THDi / THDu harmonic content is significantly increased compared to the traction condition. This result meets the requirements of feature classification and can be used for classification analysis of different data. In one embodiment, the harmonic and compensation power results are calculated by the following calculation equations:

[0144]

[0145]

[0146] Among them, the three-phase voltage on the high-voltage side of the traction transformer is u A 、u B 、u C , the secondary traction conductor voltage is u α and u β , assuming phase A is the reference voltage, then the reference vector is u A (t) = sin(ωt), the load current of the two arms is i α_l 、i β_l , I α_lf with I β_lf is the fundamental amplitude, I α_lh with I β_lh is the hth harmonic amplitude, θ α and θ β is the phase difference, inductive is negative, capacitive is positive, θ α_h ,θ β_h is the initial phase angle of the corresponding harmonics on both sides of α and β, I′ p , I' α_p , I' β_p is the active current amplitude after active power transfer balance, i' α 、i' β To compensate the current on both sides, is the current compensation signal on both sides, P is the active power, Q is the reactive power, U α and U βis the voltage amplitude of the power supply arm, and is the current reference amplitude, ψ α and ψ β is the phase angle of the corresponding power supply arm.

[0147] Step 107: construct a visualization system for the harmonics and compensation power results and power compensation status under different locomotive operating conditions.

[0148] In one embodiment, building a visualization system for harmonics and compensation power results and power compensation status under different locomotive operating conditions includes:

[0149] The parameter algorithm is combined with the locomotive harmonic source model through the GUI, so that the target parameters and power compensation status obtained by the parameter algorithm are given to the locomotive harmonic source model through the interface to build a visualization system. The power compensation results can help users obtain better visualization effects for RPC power management.

[0150] In actual use, with the increasing evolution of big data storage and analysis technology, the power quality analysis technology based on this has created a favorable technical environment for the control and exploration of the measured data of electrified railways. As far as the measured data of electric power quality of electrified railways is concerned, a robust, diverse and open data management and analysis system can be constructed to put the theoretical model proposed in this article into practical use, effectively assisting staff in the actual operation to quickly and efficiently organize the measured data of electric power quality of electrified railways, and carry out multi-dimensional data analysis and statistics, reduce human resource costs, and promote the efficient development of power quality supervision, analysis and governance. Traditional power compensation requires professional equipment such as power analyzers for measurement, which is costly and cumbersome to operate. Through the system and platform, users can obtain more intuitive and visual system results.

[0151] In order to better assign filter parameters according to different working conditions, and to make energy compensation and current more visual, a GUI interface is designed to provide users with intuitive data. Fig.13 This is the design flow chart of the power control data analysis system. This system includes modules for database analysis, waveform analysis, and power quality analysis. Database analysis includes three-phase data analysis, power factor analysis, and harmonic current analysis. The analysis of the three data and power factor can be referred to Fig.14 The interface diagram shows that users can directly view text and digital descriptions to understand the system data. Waveform analysis includes three-phase voltage and current waveform analysis, voltage imbalance waveform analysis, and power factor waveform analysis. The results can be directly viewed through the waveform module of the interface. Power quality analysis includes analysis of active and reactive compensation power, which can be directly obtained through the interface system.

[0152] The database is the core of the interconnected information of massive measured data of electrified railways. The construction of its architecture needs to meet the specific needs of power quality analysis and evaluation. At the same time, appropriate methods should be used to plan the conceptual model and logical model of the database. Fig.14 It is the ER model of the database. From the above functional architecture analysis, we can know that the electrified railway measurement database needs to contain the following basic data:

[0153] Electric energy data: load voltage value, load current value, three-phase voltage value, negative sequence current, three-phase current value, negative sequence unbalance, voltage unbalance and current unbalance.

[0154] Harmonic data: harmonic content rate, harmonic THD, harmonic amplitude, DC component, current harmonics under different working conditions, voltage harmonics under different working conditions, and three-phase current harmonic values.

[0155] The above data are stored in the workspace in real time through the operation of the simulation model, and then the workspace data are extracted and reflected in the database.

[0156] Data visualization is a key application method in big data analysis. It is a form of analysis that helps people understand complex information conveniently and quickly. This patent describes some data visualization methods and visualization design planning in the website development process. Conventional visualization methods include line charts, bar charts, column charts, pie charts, scatter charts, area charts, geographic bubble charts, pivot tables and tree diagrams, etc. In actual application, data visualization operations should be carried out according to different data requirements. For example, bar charts and vertical waterfall charts are suitable for comparing different categories of data; bar charts and curve charts are conducive to presenting the changes of key indicators over time. Therefore, choosing the right visualization method will play an extremely subtle role in website construction. The visualization arrangement of the functional modules of each part of this method is as follows. Fig.15 shown.

[0157] The logical model shows the logical structure of the data, which plays a key role in the construction process of the data warehouse. During the construction of the database, the "two-dimensional table" is generally used to show the relationship between the data. The so-called "two-dimensional table" is composed of a series of attributes. Table 6 and Table 7 are the information of the database.

[0158] Table 6 Fundamental wave data table

[0159]

[0160]

[0161] Table 7 Fundamental wave data table

[0162]

[0163] according to Fig.16 , 17 , 18, we can see the interface design appearance, as well as the traditional algorithm results of the sub-interface. By clicking on the compensation principle diagram, we can understand the compensation principle of RPC. Fig.16 There are function modules of guide module, simulation module and traditional algorithm entry. In the guide module, click Return to the previous level to return to the main interface, click Notes to understand the operation process of the simulation software, and click Working Principle to display the principle process of the RPC device. In the simulation module, first click the "Calculate LCL parameters" button to calculate the LCL filter parameters of the simulation file, and output the results to the L1, L2, C1, Rd columns, then click Start Simulation, and the results will be displayed in the editor below. The running results are shown in the figure below. Fig.17 Click the Compensation Calculation button in the function module to enter the following Fig.18 The non-simulation calculation interface shown can be used to make a simple comparison with the simulation algorithm, allowing users to initially understand the difference. Fig.18 It is embedded in the system interface and will be displayed when clicking on the compensation principle, so that users can directly understand the compensation mechanism of RPC.

[0164] The rail transit power supply energy control method based on LCL and RPC provided in an embodiment of the present invention first analyzes the grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtains the harmonic change law and power compensation state of the harmonics changing with the EMU and the traction network; constructs an LCL filter in a multiplexed RPC structure according to the harmonic change law, and obtains the resonant frequency; receives the production data of the user according to the operating state of the traction power supply system model, and designs the operating state as six types of locomotive operating conditions; simulates the locomotive harmonic source model under the six types of locomotive operating conditions through the LCL filter to obtain simulation results; then experiments are conducted on the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, and the target parameters are obtained through a variable neighborhood search algorithm to verify the rationality of the target parameters. If reasonable, the target parameters are embedded in the locomotive harmonic source model; harmonic and compensation power analysis is performed on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain harmonic and compensation power results; finally, a visualization system is constructed for the harmonic and compensation power results and power compensation states under different locomotive operating conditions. The method of the present invention can effectively analyze and control the negative sequence current and harmonic wave problems generated during the operation of high-speed railways, reduce the harm of negative sequence current to the traction power supply system and EMU equipment, extend the service life of the equipment, and reduce maintenance costs; reduce the impact of harmonics on the public power grid and train electrical equipment, reduce power loss, improve power utilization, and save energy; improve the power supply quality and reliability of the traction power supply system, reduce power supply failures, and ensure the normal operation of the high-speed railway.

[0165] The present invention combines a self-built traction power supply system model with a multiple RPC structure to obtain richer train operating conditions, analyzes in detail the harmonic current and energy compensation problems caused by locomotive traction braking on the power grid side under various operating conditions, and optimizes LCL filter parameters from a multi-operating condition perspective to perform harmonic control. The present invention can effectively control harmonic problems, reduce hidden dangers in the safe and stable operation of public power grids and trains, and improve energy utilization.

[0166] Based on the above Figure 1 The rail transit power supply energy control method based on LCL and RPC described in the corresponding embodiment is the following system embodiment of the present invention, which can be used to execute the method embodiment of the present invention.

[0167] The embodiment of the present invention provides a rail transit power supply energy control system based on LCL and RPC, such as Fig.19 As shown, the system includes: a first analysis module 201, a construction module 202, a design module 203, a simulation module 204, a calculation module 205, a second analysis module 206, and a display module 207;

[0168] The first analysis module 201 is used to analyze the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change;

[0169] A construction module 202 is used to construct an LCL filter in a multiplexed RPC structure according to a harmonic variation rule and obtain a resonant frequency;

[0170] The design module 203 is used to receive the production data of the user according to the operating state of the traction power supply system model, and design the operating state into six types of locomotive operating conditions;

[0171] The simulation module 204 is used to simulate the locomotive harmonic source model under six types of locomotive working conditions through an LCL filter to obtain simulation results;

[0172] The calculation module 205 is used to experiment the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, obtain the target parameters through the variable neighborhood search algorithm, verify the rationality of the target parameters, and if reasonable, embed the target parameters into the locomotive harmonic source model;

[0173] The second analysis module 206 is used to perform harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain harmonic and compensation power results;

[0174] The display module 207 is used to construct a visualization system for the harmonics and compensation power results and power compensation status under different locomotive operating conditions.

[0175] The rail transit power supply energy control system based on LCL and RPC provided in an embodiment of the present invention includes a first analysis module 201, a construction module 202, a design module 203, a simulation module 204, a calculation module 205, a second analysis module 206, and a display module 207; the first analysis module 201 analyzes the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtains the harmonic change law and power compensation state of the harmonics changing with the EMU and the traction network; the construction module 202 constructs an LCL filter in a multiple RPC structure according to the harmonic change law, and obtains the resonant frequency; the design module 203 receives the user's production data according to the operating state of the traction power supply system model. , and the operating state is designed as six types of locomotive operating conditions; the simulation module 204 simulates the locomotive harmonic source model under the six types of locomotive operating conditions through the LCL filter to obtain the simulation results; the calculation module 205 experiments with the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, obtains the target parameters through the variable neighborhood search algorithm, verifies the rationality of the target parameters, and if reasonable, embeds the target parameters into the locomotive harmonic source model; the second analysis module 206 performs harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results; the display module 207 constructs a visualization system for the harmonic and compensation power results under different locomotive operating conditions and the power compensation status. The system of the present invention can effectively analyze and control the negative sequence current and harmonic wave problems generated during the operation of high-speed railways, reduce the harm of negative sequence current to the traction power supply system and EMU equipment, extend the service life of the equipment, and reduce maintenance costs; reduce the impact of harmonics on the public power grid and train electrical equipment, reduce power loss, improve power utilization, and save energy; improve the power supply quality and reliability of the traction power supply system, reduce power supply failures, and ensure the normal operation of the high-speed railway.

[0176] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the system described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., various media that can store program codes.

[0177] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0178] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0179] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or systems can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

Claims

1. A rail transit power supply energy control method based on LCL and RPC, characterized in that: The method comprises: Analyze the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change; According to the harmonic variation law, an LCL filter is constructed in the multiplexed RPC structure, and the resonant frequency is obtained; According to the operating state of the traction power supply system model, receiving the production data of the user, and designing the operating state into six types of locomotive operating conditions; The locomotive harmonic source model under the six types of locomotive operating conditions is simulated by the LCL filter to obtain simulation results; Experimenting on the parameter algorithm of the LCL filter according to the simulation results and the resonant frequency, obtaining target parameters through a variable neighborhood search algorithm, verifying the rationality of the target parameters, and if reasonable, embedding the target parameters into the locomotive harmonic source model; Performing harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results; A visualization system is constructed for the harmonics and compensation power results and the power compensation status under the different locomotive operating conditions.

2. The rail transit power supply energy control method based on LCL and RPC according to claim 1 is characterized in that: The analysis of the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model to obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change specifically includes the following steps: When the working condition of the EMU changes, the corresponding harmonic characteristics are obtained to obtain the harmonic change law; The active and reactive power compensation of the grid side by the RPC device currently equipped on the EMU is obtained to obtain the power compensation state.

3. The rail transit power supply energy control method based on LCL and RPC according to claim 2 is characterized in that: The step of constructing an LCL filter in a multiplexed RPC structure according to the harmonic variation rule and obtaining a resonant frequency specifically includes: According to the law of harmonic change, a harmonic control solution combined with the RPC device is adopted, and an LCL filter is installed inside the RPC device to perform frequency scanning analysis to obtain the impedance and resonant frequency of the LCL filter; the impedance of the LCL filter includes the impedance of a single-tuned filter and the impedance of a passive damping method LCL filter.

4. The rail transit power supply energy control method based on LCL and RPC according to claim 3 is characterized in that: The impedance of the single tuned filter is calculated by the following formula: w=2πf Among them, Z s The impedance of a single tuned filter, R s is the resistance of the single tuned filter, w is the angular frequency, L is the inductance of the single tuned filter, C s is the capacitance of the single tuned filter, j is the imaginary part; The impedance of the passive damping method LCL filter is calculated by the following formula: X1=R+jwL1 Among them, Z lcl is the impedance of the passive damping method LCL filter, L1 is the first capacitor of the LCL filter, L2 is the second capacitor of the LCL filter, R is the resistance of the LCL filter, C is the capacitance of the LCL filter, X1 is the impedance of the resistor in series with the inductor L1, X2 is the impedance of the capacitor C in the LCL filter, X3 is the impedance of the inductor L2, and w is the angular frequency; The resonant frequency is calculated by the following formula: Among them, f res is the resonant frequency, L1 is the first capacitor of the LCL filter, L2 is the second capacitor of the LCL filter, and C is the capacitance of the LCL filter.

5. The rail transit power supply energy control method based on LCL and RPC according to claim 1 is characterized in that: The production data include: the three-phase system voltage is 220kV, the traction substation capacity is 40MW, the traction substation transformer ratio is 220:27.5, the AT capacity is 40MW, and the total simulation time is 2s; the traction substation wiring mode is V / v, connected to the three-phase side and the ground respectively, the traction network is powered by AT, the traction network voltage is 27.5kV, the access time under regenerative braking conditions is 1.00s, and the voltage is rated 3000V; The six types of locomotive operating conditions include: operating condition 1 is single left-side traction and right-side braking; operating condition 2 is double traction, with both power supply arms on both sides in traction operation; operating condition 3 is left-side braking and right-side traction; operating condition 4 is double-row braking, with both power supply arms on both sides in braking; operating condition 5 is single traction on the left side and no car on the right side; operating condition 6 is single braking on the left side and no car on the right side.

6. The rail transit power supply energy control method based on LCL and RPC according to claim 5 is characterized in that: The simulating of the locomotive harmonic source model under the six types of locomotive working conditions by the LCL filter to obtain the simulation results specifically includes the following steps: The CRH2 traction power supply simulation model and the RPC energy compensation device model are used to simulate the locomotive grid-side current, voltage and phase relationship under six types of locomotive operating conditions. The total harmonic content THD of the grid-side current is analyzed through the simulated structure and the double FFT harmonic analysis method of the simulation system.

7. The rail transit power supply energy control method based on LCL and RPC according to claim 1 is characterized in that: The harmonic and compensation power analysis is performed on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results, specifically comprising the following steps: By controlling the simulation of the locomotive running state, the stable harmonic at 0.08s is taken, the harmonic content of each locomotive working condition is horizontally compared, the harmonic data is analyzed, the compensation power, negative sequence imbalance, power factor, etc. are calculated, and the harmonic and compensation power results are obtained; The LCL filter parameter system is used for filtering. The parameter setting is calculated and assigned by the VNS algorithm. The external single-tuned filter uses ordinary parameters, which are C s =1.014uF, L1=18.4Mh, R=80Ω.

8. The rail transit power supply energy control method based on LCL and RPC according to claim 5, characterized in that: The harmonics and compensation power results are calculated using the following equations: Among them, the three-phase voltage on the high-voltage side of the traction transformer is u A 、u B 、u C , the secondary traction conductor voltage is u α and u β , assuming phase A is the reference voltage, then the reference vector is u A (t) = sin(ωt), the load current of the two arms is i α_l 、i β_l , I α_lf with I β_lf is the fundamental amplitude, I α_lh with I β_lh is the hth harmonic amplitude, θ α and θ β is the phase difference, inductive is negative, capacitive is positive, θ α_h ,θ β_h is the initial phase angle of the corresponding harmonics on both sides of α and β, I' p , I' α_p , I' β_p is the active current amplitude after active power transfer balance, i' α 、i' β To compensate the current on both sides, is the current compensation signal on both sides, P is the active power, Q is the reactive power, U α and U β is the voltage amplitude of the power supply arm, and is the current reference amplitude, ψ α and ψ β is the phase angle of the corresponding power supply arm.

9. The rail transit power supply energy control method based on LCL and RPC according to claim 5, characterized in that: The visualization system for constructing the harmonic and compensation power results and the power compensation status under the different locomotive operating conditions includes: The parameter algorithm is combined with the locomotive harmonic source model through a GUI, so that the target parameters and the power compensation state obtained by the parameter algorithm are given to the locomotive harmonic source model through an interface to build a visualization system.

10. A system using the rail transit power supply energy control method based on LCL and RPC as claimed in any one of claims 1 to 9, characterized in that: include: A first analysis module, a construction module, a design module, a simulation module, a calculation module, a second analysis module, and a display module; The first analysis module is used to analyze the power grid harmonics and power compensation problems of the EMU and the traction network of the traction power supply system model, and obtain the harmonic change law and power compensation state of the harmonics as the EMU and the traction network change; The construction module is used to construct an LCL filter in the multiplexed RPC structure according to the harmonic change rule and obtain the resonant frequency; The design module is used to receive the production data of the user according to the operating state of the traction power supply system model, and design the operating state into six types of locomotive operating conditions; The simulation module is used to simulate the locomotive harmonic source model under the six types of locomotive working conditions through the LCL filter to obtain simulation results; The calculation module is used to experiment the parameter algorithm of the LCL filter according to the simulation result and the resonant frequency, obtain the target parameter by a variable neighborhood search algorithm, verify the rationality of the target parameter, and if it is reasonable, embed the target parameter into the locomotive harmonic source model; The second analysis module is used to perform harmonic and compensation power analysis on different locomotive operating conditions of the traction power supply system model according to the target parameters to obtain the harmonic and compensation power results; The display module is used to construct a visualization system for the harmonics and compensation power results and the power compensation status under the different locomotive operating conditions.

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