6 9 22 9 ELECTRI C MACHINES AND CONTROL Vol. 6 No. 9 Sep. 22 EPS 2. 23 2. 23 EPS PID 76% 7% 4 km /h 28% ~ 32% 4% PID TP 29 U 463. 4 A 7-449X 22 9-3- 6 Reverse assistance control and tests of electric vehicle EPS system under anti-wind interference condition ZHAO Jing-bo ZHOU Bing 2 BEI Shao-yi. School of Mechanical and Automotive Engineering Jiangsu Teachers University of Technology Changzhou 23 China 2. School of Computer Engineering Jiangsu Teachers University of Technology Changzhou 23 China Abstract The offset along the anti-wind direction is caused under anti-wind interference condition. And the steering wheel being passively deflected to the same direction of wheel influences the vehicle stability. The electric power steering EPS dynamic model and full-vehicle two degree-of-freedom DOF model with the lateral wind interference were established. The reverse assistance strategy and flexible-pid control method were designed. The reverse assistance control was adopted to avoid excessive side driving with no driver input. The real vehicle test system was designed by simulating crosswind with high-speed flow. The results show that the average lateral displacement of the reference base to vehicle axis were respectively reduced by 76% and 7% than the forward assistance control and no assistance control. Under 4 km / h condition the peak and average value of yaw rate and lateral acceleration were reduced by 28% ~ 32% and the lateral displacement was reduced by 4% compared with no control condition. The stability attitude was significantly improved and showed better handling and stability performance. Key words electric vehicle electric power steering reverse assistance control control strategy flexible-pid control lateral wind interference condition 2 - - 5 58752 BK22586 KJD58 25 BM2826 CM23 98 968 968
4 6 ω m = θ m T m T L = K r θ m - Gθ e K r G - electric power steering EPS ECU 转矩 转矩传感器电压 车速 2 减速机构 EPS EPS 3 T h 兹 s T sen I T m PID a 兹 e T w EPS EPS a EPS Fig. Dynamics analysis of EPS system EPS J e θ e + B e θ e = T sen + GT L - T w 3 J e B e T w EPS b 4 EPS m r ẍ r + B r x r = T w - F r TR 4 p - - J s θ s + B s θ s = T h - T sen θ m 电流电动机离合器 齿轮齿条 (a)eps 系统构成 扭矩传感器 J s B s θ s θ e K s T h x r T sen = K s θ s - θ e J s θ s + B s θ s + K s θ s = T h + K s x r EPS J m θ m + B m θ m + K mr θ m = T m + GK mr U ECU 电动机减速机构 X 齿轮齿条机构 (b)eps 系统动力学分析 m r B r x r F TR J m θ m + B m θ m = T m - T L 2 θ m θ s M J m B m r ẍ r + B r x r + K r x r = GK mr + K r s - F δ p 5
9 EPS 5 X = θ s θ [ s x r x r θ m θ m ] U = [ T h T m F ] T Y = [ T sen T L θ s θ s θ m xr ] A = X = A X + B U Y = C X + D U } δ T T EPS - K s J s - B s J s K s J s K s M r - K r M r - B r M r K r G M r B = K r G J m - K r J m J s - M r J m 6 - B m J - K s K s - K rg K r r p C = D = 2 m e M zw A c M c v F yw 3 Fig. 3 Full vehicle dynamics under anti-wind v interference condition w v r τ 2 5 2 Fig. 2 w F yw V r 子 Anti-wind effect F yw A c M c e M zw 8 F yw = 2 C yρa v 2 + w 2 = 2 C yρav 2 r } M zw = ef yw 7 M zw A ρ C y 6 km /h 6 km /h C y 45 =. 9 ρ =. 225 kg /m 3 A = 5. 355 m 2 { t < F yw = 2 C y 45 ρa v 2 + w 2 t 8 3 b y V x M c M zw V y e a V A c x 啄 f
6 6 v e EPS 4 k f + k r β + v ak f - bk r ω r - mv β + ω r + F yw = k f δ } ak f - bk r β + v a2 k f + b 2 k r ωr - I z ω r + M zw = ak f δ 9 m a b I z z β EPS 模型 δ ω r X 2 = β ω r T U 2 = F yw δ Y 2 = β ω r T X2 = A 2 X 2 + B 2 U 2 Y 2 = C 2 X 2 + D 2 U 2 } K f + K r mv 3 5 5 反方助力策略 柔性 PID 控制 电流检测 整车二自指标 K f K r V 由度模型 F yw M zw 4 EPS M c Fig. 4 Reverse assistance control strategy of EPS system 8km/h 6km/h 4km/h ak f - bk r - mv 2 A 2 = 5 ak f - bk r a 2 K f + b 2 K r Fig. 5 Characteristic of reverse assistance control strategy I z I z V 5 - K f mv mv B 2 = e - ak C 2 = [ ] f D 2 = [ ] { - I max T d - T d max I T d v = - K v v T d - T d max < T d < T d max I I z I max T d T d max z M = 9 kg M s = 33 kg a = 36 mm b = 355 mm z I z = 59. 2 kg m 2 x I x =293 kg m 2 2k =35 N/rad - I max I/A PWM 控制 T dmax T d%/(n m) 4km/h 6km/h 8km/h 2k 2 = 35 N /rad h =. 5 m C T =. 2 N m /A 6-4 ~ 8 km /h 7 K b =. 2 Vs /rad PID G = 6. 5 R =. Ω L =. H J s =. 2 kg m 2 B s =. 26 N m s /rad PID K s = 9 N m /rad =. 7 8 m J m =. 47 kg m 2 PID B m =. 3 34 N m s /rad K p K d K i PID a K m = 9 N m /rad e = b c m. 4 m m < b 电动机
9 EPS 7 Table PID Parameter rules of flexible-pid control e a K p K i K d e a > 2A K p = K p /a K d = K d /c A < e a < 2A K p K i K d. 5A < e a < A K p 2 = K p /a K i 2 = K i /b K d 2 = K d c e a <. 5A K p 3 = K p /a 2 K i 3 = mk i b 2 K d 3 = K d c 2 EPS - 3 4 km /h 6 km /h 62 N 6 2 3 横摆角速度 /(rad s - ).6.5.4.3.2. 正向助力无助力 质心侧偏度 /rad..8.6.4.2 正向助力无助力.5.5 2 2.5 3 (a) 横摆角速度响应.5.5 2 2.5 3 (b) 质心侧偏角响应 侧向加速度 /(m s -2 ).4.2.8.6 正向助力.4 无助力.2.5.5 2 2.5 3 (c) 侧向加速度响应 侧向位移 /m.4.2.8.6.4.2.5.5 2 2.5 3 (d) 侧向位移 正向助力无助力 Fig. 6 6 Simulation analysis of vehicle response 2 Table 2 Peak response analysis of simulation 4 6% / rad /s. 48. 3. 24 6. % / - 2. % /rad. 9 5. 6. 4 7 58. 3% / - 2. 7% / m /s 2. 2. 692. 55 59. 2% / - 2. 4% /m. 7. 67. 532 59. 6% / - 2. 7% 3 Table 3 Average response analysis of simulation 7 4 km /h / rad /s. 24 9. 6. 3 55. 6% / - 8. 8% /rad. 4. 2 7. 2 5. 9% / - 22. 2% / m /s 2. 372. 232. 82 6. 3% / - 2. 6% /m. 23. 3. 55. % / - 22. 9% 2% 4 6 m 5 m 2 s 3 m 4 km /h 8-9
8 6 Fig. 7 3%m 实验车 试验道路 实验车 松开方向盘汽车自由行驶高压水枪 7 侧向位移参考基准 Tests under anti-wind interference condition 8 4 5. 38 m 2 EPS. 85 m. 5 m EPS 28% ~ 32% 4%. J. 2 3 59-74. 横摆角速度 /(rad s - ) 侧向加速度 /(m s -2 ).7 正向助力.6.5.4 无助力.3.2. -..5.5 2 2.5 3 (a) 横摆角速度.8.7 正向助力.6.5 无助力.4.3.2. -..5.5 2 2.5 3 (b) 侧向加速度 6 ZHAO Jingbo BEI Shaoyi ZHANG Lanchun. On reverse control strategy and anti-wind disturbance analysis of automotive EPS system J. Applied Mechanics and Materials 2 39 529-534. 8 7. EPS Bang- Fig. 8 Body response under anti-wind Bang-PID J. 2 5 96 -. interference condition ZHAO Jingbo ZHOU Bing BEI Shaoyi. Bang-Bang-PID control of automotive EPS system under damping condition J. Electric 4 Machines and Control 2 5 96 -. Table 4 Peak response analysis of tests 8. 27976. 5 P. 27 - - 6. 9. M. / rad /s. 63 7. 35. 25 8. 5% / - 28. 5% 2 252-277. / m /s 2. 759. 42. 292 8. 2% / - 3. 6% 5 Table 5 Average response analysis of tests / rad /s. 46 3. 28. 9 4 65. 4% / - 3. 7% / m /s 2. 585. 324. 29 8. 6% / - 32. 4% 5 GUAN Xin ZONG Changfu WANG Huaji. Current situation and prospect of research on subjective evaluation of vehicle chassis dynamics performance J. Chinese Journal of Automotive Engineering 2 3 59-74. 2 NAGAI Masao. Perspectives of research for enhancing active safety based on advanced control technology J. Journal of Automotive Safety and Engergy 2 4-22. 3. EPS D. 29 5-7. 4. EPS J. 2 5 2 96-2. ZHAO Jingbo ZHOU Bing LI Xiulian et al. Design and test of curved assist characteristic for electric vehicle EPS system J. E- lectric Machines and Control 2 5 2 96-2. 5. J. 2 6 6 46-49. LU Di LI Jiafeng WANG Jianxin. A highly reliable brushless DC motor speed control device J. Journal of Harbin University of Science and Technology 2 6 6 46-49.