prostep ivip Documentation Referring to PSI 11 V2 SmartSE: Domain-specific Systems Engineering Application Architectures Part 1: Plant Modeling I/F Guidelines for Vehicle Development Model Exchange Status: Adopted prostep ivip Association
Abstract General Introduction The Smart Systems Engineering (SmartSE) project within the prostep ivip Association aims to foster the industrial use of FMI by defining use cases and a process description to ensure a smooth process integration between the engineering disciplines and the collaborating partners. In order to be able to react fast regarding the fast changing state-of-the-art and domain-specific demands, a new series of documents was set up. By this, in addition to the prostep ivip SmartSE Recommendation, domain-specific guidelines for e.g. powertrain, virtual ECUs etc. can be internationally provided in a fast-track process. This series is called Domain-specific Systems Engineering Application Architectures. Document-specific Information This document is the first result of the collaboration between prostep ivip, the French Institute SystemX and the members of the MBD Group of the Japanese Ministry of Economy, Trade and Industry (METI), agreed in September 2018. It was originally specified by the METI MBD Group (Aisin, Azapa, Denso, Hitachi, Honda, Jatco, Mazda, Mitsubishi Electric, Nissan, Panasonic and Toyota). The document can be applied within powertrain development. It aims at expansion of the model distribution, the improvement of quality of reconciliation using models, and the development of human resources who can accomplish model based development in the automotive industry through consolidating model interfaces as a de facto standard at different layers including auto manufacturers, suppliers, and auto industry cluster. Furthermore, the vehicle model which conforms to this guideline is offered to promote this purpose. Thus, this document is applied to systems, which own energy. defines the direction of energy flow. defines physical signals between subsystems and their directions and unit. provides a vehicle model that conforms to itself. Thus, it complements the SmartSE Recommendation PSI 11 V2 and provides domain-specific practical application examples. Referring to PSI 11 V2 ii
Disclaimer This document is a prostep ivip Documentation (PSI Documentation), referring to PSI 11 V2. Those are freely available for all prostep ivip e.v. members. Anyone using these recommendations is responsible for ensuring that they are used correctly. This PSI Documentation gives due consideration to the prevailing state-of-the-art at the time of publication. Anyone using PSI Documentations must assume responsibility for his or her actions and acts at their own risk. The prostep ivip Association and the parties involved in drawing up the PSI Documentation assume no liability whatsoever. We request that anyone encountering an error or the possibility of an incorrect interpretation when using the PSI Documentations contact the prostep ivip Association (psi-issues@prostep.org) immediately so that any errors can be rectified. Copyright I.All rights on this PSI Documentation, in particular the copyright rights of use and sale such as the right to duplicate, distribute or publish the Documentation remain exclusively with the prostep ivip Association and its members. II.The PSI Documentation may be duplicated and distributed unchanged, for instance for use in the context of creating software or services. III.It is not permitted to change or edit this PSI Documentation. IV.A suitable notice indicating the copyright owner and the restrictions on use must always appear. Referring to PSI 11 V2 iii
Contents Table of Contents 1 Terminology... 7 1.1 System/Subsystem... 7 1.2 Control model/plant model... 7 1.3 Scope of plant model I/F (interface) guideline... 7 2 Guideline Principle... 8 2.1 Assumption in the guideline... 8 2.1.1 Assumption... 8 2.1.2 Specified Items... 8 2.2 Basic Principle... 9 2.2.1 First Principle (Variables between Plant Models)... 10 2.2.2 Second Principle (Energy Flow Direction)... 11 2.2.3 Third Principle (Input/output Direction of Variable)... 12 2.2.4 Forth Principle (Positive/Negative of Input/Output)... 13 2.2.5 Fifth Principle (Unit and Quantifier)... 14 3 Example of Guideline for Automobile System... 15 3.1 Examples... 15 3.2 Details of guideline for each physical domain... 15 3.2.1 Example of driving system... 15 3.2.2 Electric system... 17 3.2.3 Heat system... 18 4 Subsystem I/F (interface) Definition Document in an Example of Automobile... 19 4.1 Utilization of Subsystem I/F Definition Document... 19 4.2 Format of Subsystem I/F Definition Document... 19 4.3 Example of subsystem definition document... 20 4.3.1 Engine model (a model of power source of mechanical system)... 20 4.3.2 Flywheel model... 21 4.3.3 Transmission model... 22 4.3.4 Differential gear model... 23 4.3.5 Drive shaft model... 24 4.3.6 Brake system model... 25 4.3.7 Tire model... 26 4.3.8 Suspension model... 27 4.3.9 Body rigid-body motion/drive system model... 28 4.3.10 Body (air resistance) model... 29 4.3.11 Alternator model... 30 4.3.12 Low-pressure charging system model... 31 4.3.13 Starter model... 32 Referring to PSI 11 V2 iv
4.3.14 Model of each electric system... 33 4.3.15 Battery temperature control system model... 34 4.3.16 Voltage converter system model... 35 4.3.17 High-pressure charging system model... 36 4.3.18 Voltage converter system (pressurization) model... 37 4.3.19 Motor drive system model... 38 4.3.20 Climate Control System Model... 39 4.3.21 PT Thermal System Model... 40 4.3.22 Power Electronics Cooling System Model... 41 4.3.23 Heat Sink Model... 42 5 Bibliography... 43 Figures Figure 1: Definition of system and subsystem... 7 Figure 2: Positioning of plant model/control model... 7 Figure 3: Scope of plant model I/F (interface) guideline... 7 Figure 4: Input/output direction in plant model... 10 Figure 5: Energy flow direction... 11 Figure 6: Example of model which stores energy (Across variable output)... 12 Figure 7: Example of model which stores energy (Through variable output)... 12 Figure 8: Sign of signal when through variable is output... 13 Figure 9: Sign of signal when through variable is input... 13 Figure 10: Whole guideline for series parallel hybrid vehicle... 15 Figure 11: Example of input/output in a driving subsystem... 16 Figure 12: Example of flywheel... 16 Figure 13: Example of input/output in electric subsystem... 17 Figure 14: Example of input/output in a heat subsystem... 18 Figure 15: Example of subsystem I/F definition document... 19 Tables Table 1: Basic principle of plant model I/F guideline... 9 Table 2: Across variable and through variable in each physical domain... 10 Table 3: Units for across variables and through variables... 14 Referring to PSI 11 V2 v
1 Terminology 1.1 System/Subsystem A system means a vehicle. Subsystems mean parts that compose the vehicle. Figure 1: Definition of system and subsystem 1.2 Control model/plant model Subsystems are categorized into 2 types: control models which control subsystems, and plant models which are controlled by control models. Figure 2: Positioning of plant model/control model 1.3 Scope of plant model I/F (interface) guideline This guideline is applied to interfaces between plant models in subsystem. Figure 3: Scope of plant model I/F (interface) guideline Referring to PSI 11 V2 7
2 Guideline Principle 2.1 Assumption in the guideline 2.1.1 Assumption In vehicle development, for connections between subsystems of plant models, various physics including kinematics, electricity, heat, etc. need to be considered. To this end, interfaces between subsystems of plant models shall be so designed by energy flow. Besides, the following shall be also considered: It should be easy to model. It should not require heavy calculation. Modeling should be feasible. 2.1.2 Specified Items This guideline specifies the following items in plant models: Types of input/output variables Energy flow between subsystems Direction of input/output Positive/negative of through variable Unit/quantifier Referring to PSI 11 V2 8
2.2 Basic Principle The basic principles for connection between plant models are specified as follows: Table 1: Basic principle of plant model I/F guideline Basic principle 1 st Plant models shall be connected using across variables and through variables. Across variable and through variable shall be in the opposite direction. 2 nd The direction of flow from energy source to energy sink shall be considered positive direction of energy flow. 3 rd Based on elements which store the quantity of through variables and across variable, the overall I/F shall be defined. 4 th Through variable shall be regarded as positive when its input/output is in the same direction as positive flow of energy. 5th For input/output, SI unit system and SI derived unit system shall be used. For quantifier, JIS standard shall be applied. In case of deviation from the above, it shall be stated including reasons (using Subsystem I/F Definition Document). Referring to PSI 11 V2 9
2.2.1 First Principle (Variables between Plant Models) As shown in Figure 4, plant models shall be connected with across variables and through variables. The direction of through variable s signal and across variable s signal shall be opposite each other. Figure 4: Input/output direction in plant model Across variable shall be physical quantity which indicates energy potential while through variable shall be physical quantity which indicates energy flow. The following equation shall hold: Power (W) = Across variable Through variable Across variables and through variables in each physical domain are shown in Table 2. Table 2: Across variable and through variable in each physical domain Physical Across variable Through variable Domain Electrical Potential/voltage Current Translational Velocity Force Rotational Angular Velocity Torque Heat Temperature Heat flow Physical domains which are not shown in Table 2 shall be discussed and determined in the future. Referring to PSI 11 V2 10
2.2.2 Second Principle (Energy Flow Direction) The direction of flow from energy source to energy sink shall be regarded as positive. An example of mechanical system of automobile is shown below: Figure 5: Energy flow direction Energy source and sink shall be defined considering a whole system. In the plant model of powertrain system used to study fuel economy or engine performance, the engine is the energy source and the body is the energy sink. Referring to PSI 11 V2 11
2.2.3 Third Principle (Input/output Direction of Variable) The subsystems shown in Figure 6 receive through variables from adjacent subsystems while sending across variables to them. Figure 6: Example of model which stores energy (Across variable output) The subsystems shown in Figure 7 receive across variables from adjacent subsystems while sending through variables to them. Figure 7: Example of model which stores energy (Through variable output) For other subsystems, whether they receive through variables or across variables shall be determined depending on the flow of signals of through variables/across variables. Referring to PSI 11 V2 12
2.2.4 Forth Principle (Positive/Negative of Input/Output) Through variable shall be regarded as positive when it flows in the direction of positive energy flow and regarded as negative when it flows in the opposite direction of energy flow. (Figure 8 and Figure 9). Figure 8: Sign of signal when through variable is output Figure 9: Sign of signal when through variable is input Referring to PSI 11 V2 13
2.2.5 Fifth Principle (Unit and Quantifier) Units and quantifiers for each physical domain are shown in Table 3. Table 3: Units for across variables and through variables Domain Across variable Quantifier Unit Through variable Quantifier Unit Electrical Voltage V V Current I A Translational Velocity V m/s Force F N Rotational Heat Angular Velocity Temperature ω rad/s Torque M, T Nm T K Heat flow φ W Physical domains which are not shown in Table 3 shall be discussed and determined in the future. Referring to PSI 11 V2 14
3 Example of Guideline for Automobile System 3.1 Examples Figure 10 shows an example of application of the guideline to a series parallel hybrid vehicle. Figure 10: Whole guideline for series parallel hybrid vehicle 3.2 Details of guideline for each physical domain 3.2.1 Example of driving system Since tires are rotated by energy generated by the engine, defining the engine as the energy source and the Body as the energy sink, energy flow is determined. (See yellow arrows in Figure 11) In a flywheel, in accordance with the third principle, through variables are sent from adjacent subsystems (engine and transmission) while across variables are sent to them. In a drive shaft as well, in accordance with the third principle, across variables are sent from adjacent subsystems (engine and transmission) while through variables are sent to them. For other subsystems, the direction of through/across variables is determined based on the flow of these subsystems. In accordance with the first principle, across variables are connected in the opposite direction to through variables. Figure 11 illustrates this. Referring to PSI 11 V2 15
3.2.1.1 Figure 11: Example of input/output in a driving subsystem 3.2.1.2 Flywheel Depending on the types of transmission (MT, AT, CVT, HEV, etc.), the system that has jurisdiction over flywheel varies. (In case of MT, it should be the engine. In other cases, it is likely to be the transmission.) In this guideline, I/F is determined regarding the flywheel as a single model. Figure 12: Example of flywheel Referring to PSI 11 V2 16
3.2.2 Electric system For electric systems, I/F is determined, defining systems which generate electric energy (such as generator) as the energy source and parts which consume electric energy as the energy sink respectively. In this case, two MGs, which are motor drive systems, are the energy source. Starter and each electric system are the energy sink because they consume electricity. The alternator is defined as the energy source as it generates electric energy like MG s. Figure 13 illustrates this. Figure 13: Example of input/output in electric subsystem Referring to PSI 11 V2 17
3.2.3 Heat system For heat systems, individual driving systems and electric systems are the heat sources. Thus, they are defined as the energy sources while heat sinks such as engine compartment are defined as the energy sink. In the actual physical phenomenon, heat is transferred from the energy source through PT/thermal system to the energy sink. Figure 14 illustrates this. Figure 14: Example of input/output in a heat subsystem Referring to PSI 11 V2 18
4 Subsystem I/F (interface) Definition Document in an Example of Automobile 4.1 Utilization of Subsystem I/F Definition Document When models are distributed, I/F shall be confirmed in accordance with the Subsystem I/F Definition Document. This definition document may be used to describe I/Fs such as control models and monitors. 4.2 Format of Subsystem I/F Definition Document Figure 15 shows the contents of Subsystem I/F Definition Document. Figure 15: Example of subsystem I/F definition document Examples of initial the version of subsystem I/F definition document are given in the following. Referring to PSI 11 V2 19
4.3 Example of subsystem definition document 4.3.1 Engine model (a model of power source of mechanical system) Referring to PSI 11 V2 20
4.3.2 Flywheel model Referring to PSI 11 V2 21
4.3.3 Transmission model Referring to PSI 11 V2 22
4.3.4 Differential gear model Referring to PSI 11 V2 23
4.3.5 Drive shaft model Referring to PSI 11 V2 24
4.3.6 Brake system model Referring to PSI 11 V2 25
4.3.7 Tire model Referring to PSI 11 V2 26
4.3.8 Suspension model Referring to PSI 11 V2 27
4.3.9 Body rigid-body motion/drive system model Referring to PSI 11 V2 28
4.3.10 Body (air resistance) model Referring to PSI 11 V2 29
4.3.11 Alternator model Referring to PSI 11 V2 30
4.3.12 Low-pressure charging system model Referring to PSI 11 V2 31
4.3.13 Starter model Referring to PSI 11 V2 32
4.3.14 Model of each electric system Referring to PSI 11 V2 33
4.3.15 Battery temperature control system model Referring to PSI 11 V2 34
4.3.16 Voltage converter system model Referring to PSI 11 V2 35
4.3.17 High-pressure charging system model Referring to PSI 11 V2 36
4.3.18 Voltage converter system (pressurization) model Referring to PSI 11 V2 37
4.3.19 Motor drive system model Referring to PSI 11 V2 38
4.3.20 Climate Control System Model Referring to PSI 11 V2 39
4.3.21 PT Thermal System Model Referring to PSI 11 V2 40
4.3.22 Power Electronics Cooling System Model Referring to PSI 11 V2 41
4.3.23 Heat Sink Model Referring to PSI 11 V2 42
5 Bibliography NN: Guideline for FMI Model Connection using Noncausal Modeling Tool, V1.0, http://tech.jsae.or.jp/katsudou/view.aspx?id=1410, Joint Research Center, Society of Automotive Engineers of Japan, Committee of Model Development and Distribution by International Standard Description, Model Connection Technique WG, March 2015 NN: Smart Systems Engineering, Simulation Model Exchange, V2.0, https://www.prostep.org/, prostep ivip Assiocation, SmartSE Project Group, ISBN 978-3-9812689-6-6, April 2018 Referring to PSI 11 V2 43