Charging pile characteristic simulation system and method based on power-in-the-loop simulation

Abstract

The embodiments of this specification provide a charging pile feature simulation system and method based on power-in-the-loop simulation, wherein the system includes: a charging pile operating condition simulation device, which is used to simulate the charging signals under normal charging and abnormal charging conditions of a real electric vehicle; a charging pile feature acquisition device, which is used to automatically acquire the charging gun head signal of the charging pile, acquire the charging signals under normal charging and abnormal charging conditions of a real electric vehicle, and simulate the dynamic characteristics of the battery voltage at the vehicle end, so as to realize charging control feature acquisition, charging fault feature acquisition, electrical performance acquisition and communication protocol acquisition; a charging pile feature modeling host, which is used to extract the features of the charging pile and build a model based on the charging gun head signal, and generate various types of charging pile feature simulation models; a charging pile feature simulation device, which is used to realize charging control feature simulation, charging fault feature simulation, electrical performance simulation and communication protocol simulation.

Description

Technical Field

[0001] This document relates to the field of computer technology, and in particular to a charging pile characteristic simulation system and method based on power-in-the-loop simulation. Background Art

[0002] Electric vehicles have many advantages such as high torque, zero pollution and low noise. The development of electric vehicles will help alleviate the dual pressure of energy and environment. Research on the compatibility between electric vehicles and charging piles has important practical significance.

[0003] Newly produced electric vehicles have passed the national charging standard test before being put on the market. However, because they are all tested under standard test cases, the standard test case verification of electric vehicles cannot cover most of the charging characteristics of charging piles. Automakers generally conduct additional on-site real-pile and real-vehicle charging pile compatibility tests as standard supplementary verification tests to address the limitations of test case-based verification in the standards. Summary of the invention

[0004] The purpose of the present invention is to provide a charging pile characteristic simulation system and method based on power-in-the-loop simulation, aiming to solve the above-mentioned problems in the prior art.

[0005] The present invention provides a charging pile characteristic simulation system based on power-in-the-loop simulation, comprising:

[0006] A charging pile working condition simulation device, connected to the charging pile feature acquisition device, is used to simulate the charging signals under normal charging and abnormal charging conditions of a real electric vehicle;

[0007] Charging pile feature acquisition equipment is connected to the charging pile working condition simulation equipment and the charging pile feature modeling host, and is used to automatically acquire the charging gun head signal of the charging pile, acquire the charging signal under normal charging and abnormal charging conditions of the real electric vehicle, and simulate the dynamic characteristics of the battery voltage at the vehicle end, so as to realize the acquisition of charging control characteristics, charging fault characteristics, electrical performance and communication protocol;

[0008] A charging pile feature modeling host, connected to the charging pile feature simulation device, is used to extract the features of the charging pile and build a model based on the charging gun head signal, and generate various types of charging pile feature simulation models;

[0009] The charging pile characteristic simulation device is connected to the electric vehicle and is used to perform real-time simulation of the charging and guidance characteristics of the charging pile based on the charging pile characteristic simulation model, simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current, and realize charging control characteristic simulation, charging fault characteristic simulation, electrical performance simulation and communication protocol simulation.

[0010] The present invention provides a charging pile feature simulation method based on power-in-the-loop simulation, which is used in the above-mentioned charging pile feature simulation system based on power-in-the-loop simulation, and the method comprises:

[0011] The charging pile working condition simulation device is used to simulate the charging signals of real electric vehicles under normal charging and abnormal charging conditions;

[0012] The charging pile feature acquisition device automatically collects the charging gun head signal of the charging pile, collects the charging signal of the real electric vehicle under normal charging and abnormal charging conditions, and simulates the dynamic characteristics of the battery voltage at the vehicle end to realize the collection of charging control characteristics, charging fault characteristics, electrical performance and communication protocol;

[0013] The charging pile feature modeling host extracts the features of the charging pile and builds a model based on the charging gun head signal to generate various types of charging pile feature simulation models;

[0014] The charging pile characteristic simulation device is used to simulate the charging and guidance characteristics of the charging pile in real time based on the charging pile characteristic simulation model, and simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current to achieve charging control characteristic simulation, charging fault characteristic simulation, electrical performance simulation and communication protocol simulation.

[0015] The use of the embodiment of the present invention and the use of power-in-the-loop simulation are beneficial to shortening the development cycle of the system. In addition to using mathematical models to describe objective things, some physical hardware is also connected to the simulation system to make the simulation system closer to the real system. A complete set of charging pile power-in-the-loop simulation systems has the advantages of saving development costs, rapid prototyping, reproducible states, comprehensive simulation, and high safety. The charging pile model is built in the simulation host, and the output characteristics of charging piles from various manufacturers can be reproduced by using the charging pile feature simulation device to connect with the electric vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate one or more embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 is a schematic diagram of a charging pile characteristic simulation system based on power-in-the-loop simulation according to an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of a charging pile characteristic model according to an embodiment of the present invention;

[0019] Figure 3 is a schematic diagram of an electrical model of a charging pile according to an embodiment of the present invention;

[0020] Figure 4 is a schematic diagram of a charging pile communication model according to an embodiment of the present invention;

[0021] Figure 5 It is a flow chart of a charging pile characteristic simulation method based on power-in-the-loop simulation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the following will be combined with the drawings in one or more embodiments of this specification to clearly and completely describe the technical solutions in one or more embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this document.

[0023] System Example

[0024] According to an embodiment of the present invention, a charging pile characteristic simulation system based on power-in-the-loop simulation is provided. Figure 1 is a schematic diagram of a charging pile characteristic simulation system based on power-in-the-loop simulation according to an embodiment of the present invention. Figure 1 As shown, the charging pile characteristic simulation system based on power-in-the-loop simulation according to an embodiment of the present invention specifically includes:

[0025] The charging pile operating condition simulation device 10 is connected to the charging pile feature acquisition device, and is used to simulate the charging signals under normal charging and abnormal charging conditions of a real electric vehicle; the abnormal charging conditions of a real electric vehicle simulated by the charging pile operating condition simulation device 10 specifically include: insulation failure, communication interruption, charging interface disconnection, abnormal single battery voltage, abnormal SOC of the whole vehicle power battery, abnormal power battery charging current, abnormal power battery temperature, abnormal power battery insulation state, abnormal power battery output connector connection state, and output connector overtemperature failure.

[0026] The charging pile feature acquisition device 12 is connected to the charging pile working condition simulation device and the charging pile feature modeling host, and is used to automatically acquire the charging gun head signal of the charging pile, acquire the charging signal under normal charging and abnormal charging conditions of the real electric vehicle, and simulate the dynamic characteristics of the battery voltage at the vehicle end, so as to realize the charging control characteristic acquisition, charging fault characteristic acquisition, electrical performance acquisition and communication protocol acquisition; wherein, the charging gun head signal includes at least one of the following: output voltage, output current, control guide voltage, communication message and auxiliary power supply signal. The charging signal includes at least one of the following: power characteristics, electrical characteristics and BMS message.

[0027] The charging pile feature modeling host 14 is connected to the charging pile feature simulation device and is used to extract the features of the charging pile and build a model based on the charging gun head signal to generate multiple types of charging pile feature simulation models; the types of charging piles simulated by the charging pile feature simulation model specifically include: national standard charging piles, V2G charging piles and high-power charging piles. The charging pile feature modeling host 14 is specifically used to:

[0028] Perform numerical simulation of charging of charging piles, generate charging pile electrical model, charging pile interoperability function model, charging pile communication model and CAN communication fault model, and perform hardware driver simulation of charging piles, wherein the hardware driver specifically includes: AI board, AO board, DI board, DO board, and CAN board. Specifically,

[0029] The front-stage Vienna rectifier uses a three-level rectifier, and the back-stage DC / DC uses a Buck-Boost circuit. Based on the mathematical model of the Vienna rectifier in the dq coordinate system, the PI controllers of the current inner loop and voltage outer loop of the Vienna rectifier are designed to achieve dual closed-loop control of the rectifier system. The Buck-Boost circuit is controlled by the dual closed-loop PI control of the current inner loop and the voltage outer loop to achieve constant voltage and constant current output functions, and generate the electrical model of the charging pile;

[0030] According to the four stages of CAN communication between the off-board charger and the battery BMS during the charging process: handshake identification stage, charging parameter configuration stage, charging process stage, and charging end stage, the entire communication process is monitored and controlled. At each stage, the state machine is used to describe the jump branch, message cycle, content, delay and jitter, which are used as configuration model parameters to generate the charging pile communication model.

[0031] The simulation of the guide signals CC1, CC2, the low-voltage auxiliary sources A+, A-, and the on-off of the high-voltage switches K1, K2, and the low-voltage auxiliary source switches K3, K4 are simulated, and the charging control state, charging connection timing, and abnormal charging state of the charging pile are simulated to generate a charging pile interoperability functional model.

[0032] The charging pile characteristic simulation device 16 is connected to the electric vehicle and is used to simulate the charging and guiding characteristics of the charging pile in real time based on the charging pile characteristic simulation model, simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current, and realize charging control characteristic simulation, charging fault characteristic simulation, electrical performance simulation and communication protocol simulation. The charging pile characteristic simulation device 16 is specifically used to: use the FPGA-based detailed model small step length scheme to build the model, simulate the characteristics of the V2G charging pile and the high-power charging pile in detail, and simulate the electromagnetic transient characteristics under faults or special working conditions.

[0033] The charging pile characteristic simulation device 16 specifically includes:

[0034] The chassis includes a backplane control component, and the controller and the multi-function card communicate through the control signal bus and clock signal bus of the backplane control component to realize various functions; the controller includes a multi-core CPU for decoupling and high-speed computing of the model; the multi-function card is used for performing signal digital-to-analog conversion, collection of various physical and electrical quantities, multi-channel switching, and fault injection.

[0035] From the above description, it can be seen that the charging pile feature acquisition device is used to automatically collect all the charging gun head signals such as the output voltage, output current, control guide voltage, communication message, auxiliary power signal of the tested charging device, and complete the feature extraction and model building in the charging pile feature modeling host. The DC charging pile feature simulation device is used to connect with the electric vehicle to reproduce the output characteristics of each device. The charging pile model building mainly includes: national standard charging pile, V2G charging pile, and high-power charging pile. The model building adopts a small step length scheme of the detailed model based on FPGA, which can simulate the characteristics of V2G charging piles, high-power charging piles, etc. in detail, and can simulate the electromagnetic transient characteristics under faults or special working conditions. Use simulation software to build the DC charging pile model, and then use the model interface tool to convert the offline model into a real-time model and download it to the hardware for real-time simulation.

[0036] Power-in-the-loop simulation is an important step in system development and design, which is conducive to shortening the system development cycle. In addition to using mathematical models to describe objective things, some physical hardware is also connected to the simulation system to make the simulation system closer to the real system. A complete set of charging pile power-in-the-loop simulation system has the advantages of saving development costs, rapid prototyping, reproducible state, comprehensive simulation, and high safety.

[0037] The traditional method of charging compatibility testing of electric vehicles requires matching a large number of charging piles from mainstream manufacturers, which is inefficient and time-consuming. The charging pile characteristic simulation system based on hardware-in-the-loop simulation in the embodiment of the present invention completes the construction of the charging pile model in the simulation host, and uses the charging pile characteristic simulation device to connect with the electric vehicle to reproduce the output characteristics of the charging piles of various manufacturers.

[0038] The above technical solution of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings.

[0039] 1. DC charging pile feature collection equipment

[0040] The DC charging pile feature acquisition equipment includes an analog input conditioning module and a 16-channel analog recording module. The analog input conditioning module performs differential sampling on the voltage and current signals and amplifies the amplitude to within the range of ±10V; the 16-channel analog recording module performs AD sampling on the signals conditioned by the upper level and uploads the acquired data to the CPU through a parallel bus. With the cooperation of the DC charging pile working condition simulation equipment, charging signals under normal charging and abnormal charging conditions are collected, and the dynamic characteristics of the battery voltage at the vehicle end are simulated. Communicate with the DC charging pile working condition simulation equipment via RS485. The charging characteristics and acquisition content are shown in Table 1.

[0041] Table 1

[0042]

[0043] 2. DC charging pile working condition simulation equipment

[0044] The DC charging pile operating condition simulation equipment can simulate the power characteristics, electrical characteristics and BMS messages under normal and abnormal charging conditions of the real vehicle.

[0045] The states of abnormal DC charging conditions include: insulation failure, communication interruption, charging port disconnection, abnormal single battery voltage, abnormal vehicle power battery SOC, abnormal power battery charging current, abnormal power battery temperature, abnormal power battery insulation state, abnormal power battery output connector connection state, and output connector overtemperature failure.

[0046] 3. DC charging pile characteristic simulation equipment

[0047] The DC charging pile characteristic simulation device simulates the charging and guidance characteristics of the charging pile in real time. It is a key device in the PHIL simulation system. Its maximum power is 120kW and the maximum voltage is 1000VDC. The DC charging pile characteristic simulation device includes an interoperability simulation module, an electrical performance simulation module, and a communication protocol simulation module. It can simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current. The charging performance and characteristic simulation items are shown in Table 2.

[0048] Table 2

[0049]

[0050] 4. Charging pile feature modeling host

[0051] The host of charging pile feature modeling mainly includes the following important parts: chassis, controller, and multi-function card. The chassis mainly has a backplane control component. The controller and its multi-function card communicate through the backplane control signal bus and the clock signal bus to realize various functions; the controller is composed of a multi-core CPU, which mainly performs model decoupling and high-speed calculation; the multi-function card is mainly responsible for signal digital-to-analog conversion, the collection of various physical and electrical quantities, multi-channel switching, fault injection and other functions.

[0052] The charging pile feature modeling host adopts a high-speed bus structure and a modular design. The backplane uses a standard high-speed communication interface to facilitate the upgrade and expansion of the test card.

[0053] Charging pile modeling method:

[0054] The characteristic power-in-the-loop simulation system of the charging pile not only tests the signal level of the pilot circuit and CAN communication message, but also needs to simulate the working state of the charging pile in the real pile environment. Therefore, it is necessary to build a real-time simulation model for the charging pile. The accuracy of the simulation model is crucial to the entire PHIL test system. Its rationality, accuracy, and functionality directly affect the use of the entire system. The test model established in this paper is as follows Figure 2 The charging pile model types are shown in Table 3.

[0055] Table 3

[0056]

[0057] Charging pile electrical model construction:

[0058] The core of the charging pile electrical model is the power module modeling. The power module uses a two-stage circuit. The front-stage Vienna rectifier is a three-level rectifier, and the rear-stage DC / DC part uses a Buck-Boost circuit. The overall electrical model is as follows: Figure 3 shown.

[0059] Based on the mathematical model of Vienna rectifier in dq coordinate system, the PI controller of the inner current loop and the outer voltage loop of Vienna rectifier is designed, so as to realize the dual closed-loop control of rectifier system, improve the working stability of the system, and accelerate the dynamic response speed of the system [3]. The control of Buck-Boost circuit also adopts the dual closed-loop PI control of the inner current loop and the outer voltage loop to realize the constant voltage and constant current output function.

[0060] Charging pile communication model construction:

[0061] During the charging process, the off-board charger and the battery BMS communicate via CAN to exchange the charging status and requirements of both parties. The communication process can be divided into four stages: handshake identification stage, charging parameter configuration stage, charging process to charging end stage, and the entire process is monitored and controlled. Figure 4 As shown, a state machine is used to describe jump branches at each stage, and the message cycle, content, delay, and jitter can all be configured as model parameters.

[0062] Charging pile interoperability functional model construction:

[0063] The charging pile interoperability functional model completes the simulation of the guidance signals CC1, CC2, low-voltage auxiliary sources A+, A-, and the on-off of high-voltage switches K1, K2, and low-voltage auxiliary source switches K3, K4, and is used to simulate the charging control status, charging connection timing, and abnormal charging status of the charging pile.

[0064] The interoperability functional model is synchronized with the electrical model and the communication model, which together constitute the characteristics of the charging pile.

[0065] Method Embodiment

[0066] According to an embodiment of the present invention, a charging pile feature simulation method based on power-in-the-loop simulation is provided, which is used in the charging pile feature simulation system based on power-in-the-loop simulation in the above system embodiment. Figure 5 is a flow chart of a charging pile characteristic simulation method based on power-in-the-loop simulation according to an embodiment of the present invention. Figure 5 As shown, the charging pile characteristic simulation method based on power-in-the-loop simulation according to an embodiment of the present invention specifically includes:

[0067] Step 501, simulating charging signals under normal charging and abnormal charging conditions of a real electric vehicle through a charging pile working condition simulation device;

[0068] Step 502, automatically collecting the charging gun head signal of the charging pile through the charging pile feature collection device, collecting the charging signal under normal charging and abnormal charging conditions of the real electric vehicle, and simulating the dynamic characteristics of the battery voltage at the vehicle end, realizing the collection of charging control characteristics, charging fault characteristics, electrical performance and communication protocol;

[0069] Step 503, extracting the characteristics of the charging pile and building a model based on the charging gun head signal through the charging pile characteristic modeling host, and generating multiple types of charging pile characteristic simulation models;

[0070] Step 504, based on the charging pile characteristic simulation model, a charging pile characteristic simulation device is used to perform real-time simulation of the charging and guidance characteristics of the charging pile, simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current, and realize charging control characteristic simulation, charging fault characteristic simulation, electrical performance simulation and communication protocol simulation.

[0071] The embodiment of the present invention is a method embodiment corresponding to the above-mentioned system embodiment. The specific operation of each step can be understood by referring to the description of the system embodiment, which will not be repeated here.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A charging pile characteristic simulation system based on power-in-the-loop simulation, characterized in that: include: A charging pile working condition simulation device, connected to the charging pile feature acquisition device, is used to simulate the charging signals under normal charging and abnormal charging conditions of a real electric vehicle; Charging pile feature acquisition equipment is connected to the charging pile working condition simulation equipment and the charging pile feature modeling host, and is used to automatically acquire the charging gun head signal of the charging pile, acquire the charging signal under normal charging and abnormal charging conditions of the real electric vehicle, and simulate the dynamic characteristics of the battery voltage at the vehicle end, so as to realize the acquisition of charging control characteristics, charging fault characteristics, electrical performance and communication protocol; A charging pile feature modeling host, connected to the charging pile feature simulation device, is used to extract the features of the charging pile and build a model based on the charging gun head signal, and generate various types of charging pile feature simulation models; A charging pile characteristic simulation device is connected to the electric vehicle and is used to perform real-time simulation of the charging and guiding characteristics of the charging pile based on the charging pile characteristic simulation model, simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current, and realize charging control characteristic simulation, charging fault characteristic simulation, electrical performance simulation and communication protocol simulation; the charging pile characteristic simulation device is specifically used to: adopt a detailed model small step length scheme based on FPGA to build a model, simulate the characteristics of V2G charging piles and high-power charging piles in detail, and simulate electromagnetic transient characteristics under faults or special working conditions; The charging pile characteristic simulation device specifically includes: The chassis includes a backplane control component, and the controller and the multi-function card communicate through the control signal bus and clock signal bus of the backplane control component to realize various functions; the controller includes a multi-core CPU for decoupling and high-speed computing of the model; the multi-function card is used for signal digital-to-analog conversion, acquisition of various physical and electrical quantities, multi-channel switching, and fault injection; The charging pile feature modeling host is specifically used for: Perform numerical simulation of charging of charging piles, generate charging pile electrical model, charging pile interoperability function model, charging pile communication model and CAN communication fault model, and perform hardware driver simulation of charging piles, wherein the hardware driver specifically includes: AI board, AO board, DI board, DO board, and CAN board; The front-stage Vienna rectifier uses a three-level rectifier, and the back-stage DC / DC uses a Buck-Boost circuit. Based on the mathematical model of the Vienna rectifier in the dq coordinate system, the PI controllers of the current inner loop and voltage outer loop of the Vienna rectifier are designed to achieve dual closed-loop control of the rectifier system. The Buck-Boost circuit is controlled by the dual closed-loop PI control of the current inner loop and the voltage outer loop to achieve constant voltage and constant current output functions, and generate the electrical model of the charging pile; According to the four stages of CAN communication between the off-board charger and the battery BMS during the charging process: handshake identification stage, charging parameter configuration stage, charging process stage, and charging end stage, the entire communication process is monitored and controlled. At each stage, the state machine is used to describe the jump branch, message cycle, content, delay and jitter, which are used as configuration model parameters to generate the charging pile communication model. The simulation of the guide signals CC1, CC2, the low-voltage auxiliary sources A+, A-, and the on-off of the high-voltage switches K1, K2, and the low-voltage auxiliary source switches K3, K4 are simulated, and the charging control state, charging connection timing, and abnormal charging state of the charging pile are simulated to generate a charging pile interoperability functional model.

2. The system according to claim 1, characterized in that The charging gun head signal includes at least one of the following: output voltage, output current, control guide voltage, communication message and auxiliary power supply signal.

3. The system according to claim 1, characterized in that The charging signal includes at least one of the following: power characteristics, electrical characteristics and BMS message.

4. The system according to claim 1, characterized in that The types of charging piles simulated by the charging pile characteristic simulation model specifically include: national standard charging piles, V2G charging piles and high-power charging piles.

5. The system according to claim 1, characterized in that The abnormal charging conditions of a real electric vehicle simulated by the charging pile operating condition simulation device specifically include: insulation failure, communication interruption, disconnection of the charging interface, abnormal voltage of a single battery, abnormal SOC of the power battery of the whole vehicle, abnormal charging current of the power battery, abnormal temperature of the power battery, abnormal insulation state of the power battery, abnormal connection state of the power battery output connector, and over-temperature failure of the output connector.

6. A charging pile characteristic simulation method based on power-in-the-loop simulation, characterized in that: A charging pile characteristic simulation system based on power-in-the-loop simulation for use in any one of claims 1 to 5, wherein the method specifically comprises: The charging pile working condition simulation device is used to simulate the charging signals of real electric vehicles under normal charging and abnormal charging conditions; The charging pile feature acquisition device automatically collects the charging gun head signal of the charging pile, collects the charging signal of the real electric vehicle under normal charging and abnormal charging conditions, and simulates the dynamic characteristics of the battery voltage at the vehicle end to realize the collection of charging control characteristics, charging fault characteristics, electrical performance and communication protocol; The charging pile feature modeling host extracts the features of the charging pile and builds a model based on the charging gun head signal to generate various types of charging pile feature simulation models; The charging pile characteristic simulation device is used to simulate the charging and guidance characteristics of the charging pile in real time based on the charging pile characteristic simulation model, and simulate the output characteristics of the charging pile CC1, CC2, auxiliary power supply, CAN message, DC voltage and current to achieve charging control characteristic simulation, charging fault characteristic simulation, electrical performance simulation and communication protocol simulation.

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