GRPE/HDH-03-04 -Base Emissions Regulation using HILS for Commercial Hybrid Vehicles JASIC 1
Regulation of Emissions from Commercial Vehicles--- Needs for -Base Compared to passenger cars, heavy commercial vehicles have much wider variety of configurations. In addition, different engines, transmissions, gear ratios, tyres and equipments are selected based on each user s needs. Separate engine performance standards are an important part of a successful regulatory program for commercial vehicles. This is beneficial not only for emissions certification, but also for the whole engine and vehicle development process. In the current Japanese exhaust emission regulatory framework, both engine dynamo testing and chassis dynamo testing are available, and none of Japanese heavy-duty manufacturer request chassis approach. 2
Regulation of Emissions from Commercial Vehicles--- Needs for -Base (continued) WHTC adopt micro-transient engine operation, and includes frequent small accelerations and decelerations. The operation can be obtained only through preprogramming of electronically controlled engine dynamometer operation. In the case of chassis dynamo testing with driver s manual operation, the accuracy of micro-transient operation will not be acquired. Dynamometer-based certification of engines using micro-transient test cycle has proven to be successful in achieving the desired reductions of criteria emissions output for a wide range of vehicles and applications in Japan. In principle, the engine should be the regulated entity for heavy commercial vehicle emissions performance regulation. 3
Japanese hybrid commercial engine emissions certification using HILS Japan introduced engine-base certification procedure for commercial hybrid vehicles by applying HILS. Criteria emissions output are measured by engine only, the operation is simulated by HILS. Performances of the engine and the hybrid components are measured and certified as a set. The accuracy of simulated interactions between engine and hybrid components is certified by comparing measured and simulated results. Total fuel consumption etc. are the criteria for determining the accuracy. For the measurement, so-called system in bench method,chassis dynamo testing or actual driving on test course are applied. 4
Comparison of Chassis Dyno,HILS and Bench Test Methods Chassis Dyno Method HD-HEVs (many types) Measurement on chassis dyno SOC 0 3~5 number of test n types 5
Comparison of Chassis Dyno,HILS and Bench Test Methods (continued) HILS Method HILS Vehicle speed Time SOC 0 simulation ED dynamometer test: only Test Cycle Bench Test Method for Hybrid Systems HEV Conversion Algorithm Inverter RESS Test Vehicle MG ED dynamometer test: + HEV system SOC 0 3~5 number of test 6
Comparison of Chassis Dyno,HILS and Bench Test Methods (continued) Examination accuracy Chassis dyno Bench test HILS Certification efficiency Chassis dyno < Bench test < HILS The examination accuracy of HILS method can be put in the tolerance. The maximum advantage of the HILS method is a time and cost efficiency improvements of the certification. 7
Appendix 8
Why HILS Method? Vehicle type Fuel economy Exhaust emissions LDVs (not many types) Measurement on chassis dyno HD-CVs (many types) Nm rpm sec sec Nm FC Map rpm Fuel economy Simulation with FC map Exhaust emissions are tested on engine dyno in the world. Dyno Measurement with an engine unit HD-HEVs Although there aren't many HD-HEVs at the moment, but many types of HD-HEVs (Ex. 4WD, In-wheel motor, multi wheels) will appear in the future. Therefore the easy and efficient test method using simulation is demanded (HILS method is preferable). 9
Flow-chart of certification-test performance test 1 Tests of components in hybrid system for getting input data of component models in HILS Electric motor & inverter performance test Electric generator & inverter performance test Battery performance test 2 3 4 Test of real hybrid system for sampling time-history data to compare with simulated result by HILS HILS test Exhaust emission test Vehicle test on chassis dynamometer or engine test with hybrid system on engine dynamometer Certification of the verification of HILS by comparing HILS result with real system result Getting time-history data of engine speed and torque, 2 patterns for exhaust emission test and for fuel economy calculation. 10
Correlation Between test course driving and HILS for pre-transmission parallel hybrid architectures Reference Vehicle Speed and HILS Simulation Speed FC Reproducibility 11
Simulation Method for HD Conventional Vehicles Vehicle Speed <Vehicle Basis> Time JE05 Driving Cycles Conversion Algorithm Vehicle Data - Vehicle Mass - Road Load - Speed - Torque -Gear Ratio - Gear Efficiency Speed Load Fuel Consumption < Basis> Time T/M E/D Exhaust Emission Measuring 12
Bench Test Method for Heavy-Duty HEVs Vehicle Speed <Vehicle Basis> Inverter M/G Time JE05 Driving Cycles Energy Storage System T/M HEV Conversion Algorithm Input Items (1) Same Items with Conventional Vehicles - Vehicle Mass - Road Load - Speed - Torque -Gear Ratio - Gear Efficiency (2) Special Items Max. Regeneration Torque or Ratio of Regenerative Brake/ Mechanical Brake Hybrid System Speed Hybrid System Load <Hybrid System Basis> Control Minus Torque Inverter M/G Energy Storage System E/D Time Exhaust Emission Measuring 13
HILS Method for Heavy-Duty HEVs <Vehicle Basis> <Conversion with HILS> < Basis> Vehicle Speed JE05 Driving Cycles Time Acceleration & Braking Acceleration & Braking Driver Model Hybrid ECU Vehicle Speed JE05 Driving Cycles Energy Storage System (ESS) Inverter Speed Load Fuel Consumption MG T/M Time E/D Real HEV HEV Model HIL Simulator Exhaust Emission Measuring 14