过调制的原理(1)过调制区判断过调制分两个区分别是过调制一区和过调制二区。下面是过调制的判断从上面的图片可以看出来过调制的判断其实就是去计算电机的调制比M的大小。电机的基准电压Ubase 2*Udc/pi 0.6366UdcUd是母线电压的大小。通过计算出 M |Us| / Ubase去计算调制比M。如果M 1表示内切圆、1 M 1.1547表示调制比1区、1.1547 M 2表示调制比2区。(2)调制算法实现区分过调制1区和过调制2区的主要目的就是为了让电机从矢量圆过度到过调制的时候更加的平滑。不同的过调制区使用的办法不一样比如过调制1区可以通过最小相位误差法。过调制2区使用最小幅值误差法。最小相位误差法原理就是当合成矢量|Us| Udc / sqrt(3)的时候。通过等比例缩放将赋值缩放到六边形上面。在过调制1区里面马鞍波是被削顶最后会变成方波控制。最小幅值误差法原理是将 |Us| 与 六边型做垂直的线求出另外一条边。这条边是最大的。上面图片显示 |Us| |Uref|。做垂直线算出Uy这个Uy就是最小幅值误差计算出来的值。在过调制2区里面需要根据合成矢量 | Us| 的值去计算出黄色区域的角度范围(图片里面值展示扇区1和扇区2的部分内容)。在蓝色区域内使用“六步换相”的方式去控制在黄色区域使用“等比例缩放到六边形”的方式去控制。过调制算法的实现步骤(1)过调制算法并不难其核心就是去计算出电机的 |Us| 的大小然后去判断电机位于那个过调制区。|Us|的大小可以通过 |Us| sqrt(Uα^2 Uβ^2) 计算获取。Us sqrt(Uα^2 Uβ^2)if(Us Udc/sqrt()3)//矢量圆else if (Us 2*Udc/3)//过调制1区else if(Us 2*Udc/sqrt(3))//过调制2区(2) 求取gamma的范围这个角度的求取也是比较简单的使用的是三角函数去求解。arg 2 * Udc / (3 * U) * sin(2 * pi / 3);gamma_base pi - 2 *pi / 3 - asin(arg);然后就可以根据电机位于那个扇区去判断电机的电角度是否位于对于的角度范围之内。来决定是使用六步换相去控制还是通过等比例缩放到六边形的控制。下面是Matlab的m文件仅提供参考function [Ua, Ub, Uc, mode, MI] SVPWM_OverMod(U_alpha, U_beta, Udc) %----符号取反(适配FOC方向) U_alpha -U_alpha; U_beta -U_beta; %----单精度常里---- sqrt3 single(1.7320508075688772); pi_val single(3.141592653589793); two_pi single(6.283185307179586); two_thirds single(0.6666666666666666); %----计算幅值与角度 U sqrt(U_alpha*U_alpha U_beta*U_beta); %----计算调制比MI(核心输出) MI U / (udc / sqrt3); MI single(MI); %确保单精度 if U single(1e-6) Ua single(0.5); Ub single(0.5); Uc single(0.5); mode uint8(0); MI single(0); return; end theta atan2(U_beta, U_alpha); if theta 0 theta theta two_pi; elseif theta two_pi theta theta - two_pi; end % ----扇区判断 if U_beta 0 A 0; else A 1; end if U_beta - sqrt3 * U_alpha 0 B 0; else B 1; end if U_beta sqrt3 * U_alpha 0 C 0; else C 1; end Sector 4*A 2*B C; % ---临时变里统一初始化为single---- T1 single(0); T2 single(0); T0 single(0); scale single(0); gamma single(0) ; HA single(0); HB single(0); HC single(0); mode uint8(0); % 默认线性区 %----调制区域计算 if U Udc / sqrt3 %-线性调制区- mode uint8(0); switch Sector case 1 T1 sqrt3 * U / Udc * sin(pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta); T0 single(1) - T1 - T2; HA T0 / single(2); HB T0 / single(2) T1; HC T0 / single(2) T1 T2; case 2 T1 sqrt3 * U / Udc * sin(pi_val - theta); T2 sqrt3 * U / Udc sin(theta - single(2)*pi_val/3); T0 single(1) - T1 - T2; HA T0 / single(2) T1 T2; HB T0 / single(2); HC T0 / single(2) T1; case 3 T1 sqrt3 * U / Udc sin(single(2)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - pi_val/3); T0 single(1) - T1 - T2; HA T0 / single(2) T2; HB T0 / single(2); HC T0 / single(2) T1 T2; case 4 T1 sqrt3 * U / Udc * sin(single(5)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - single(4)*pi_val/3); T0 single(1) - T1 - T2; HA T0 / single(2) T1; HB T0 / single(2) T1 T2; HC T0 / single(2); case 5 T1 sqrt3 * U / Udc sinl-theta); T2 sqrt3 * U / Udc * sin(theta - single(5)*pi_val/3); T0 single(1) - T1 - T2; HA T0 / single(2); HB T0 / single(2) T1 T2; HC T0 / single(2) T2; case 6 T1 sqrt3 * U / Udc * sin(single(4)*pi_val/3 - theta); T2 sqrt3 * U / Ude * sin(theta - pi_val); T0 single(1) - T1 - T2; HA T0 / single(2) T1 T2; HB T0 / single(2) T2; HC T0 / single(2); end end elseif U (single(2) / single(3)) * Udc mode uint8(1); switch Sector case 1 T1 sqrt3 * U / Udc * sin(pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta); if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end HA T0 / single(2); HB T0 / single(2) T1; HC T0 / single(2) T1 T2; case 2 T1 sqrt3 * U / Udc * sin(pi_val - theta); T2 sqrt3 * U / Udc * sin(theta - single(2)*pi_val/3); if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end HA T0 / single(2) T1 T2; HB T0 / single(2); HC T0 / single(2) T1; case 3 T1 sqrt3 * U / Udc * sin(single(2)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - pi_val/3); if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end HA T0 / single(2) T2; HB T0 / single(2); HC T0 / single(2) T1 T2; case 4 T1 sqrt3 * U / Udc * sin(single(5)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - single(4)*pi_val/3); if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end HA T0 / single(2) T1; HB T0 / single(2) T1 T2; HC T0 / single(2); case 5 T1 sqrt3 * U / Udc * sin(-theta); T2 sqrt3 * U / Udc * sin(theta - single(5)*pi_val/3); if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end HA T0 / single(2); HB T0 / single(2) T1 T2; HC T0 / single(2) T2; case 6 T1 sqrt3 * U / Udc * sin(single(4)*pi_val/3 - theta); T2 sqrt3 * U / Ude * sin(theta - pi_val); if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end HA T0 / single(2) T1 T2; HB T0 / single(2) T2; HC T0 / single(2); end end elseif U (single(2) / sqrt3) * Udc mode uint8(2); mode uint8(2); arg single(2) * Udc / (single(3) * U) * sin(single(2)*pi_val/3); if arg single(1) arg single(1); end if arg -single(1) arg -single(1); end gamma_base pi_val - single(2)*pi_val/3 - asin(arg); switch Sector case 1 T1 sqrt3 * U / Udc * sin(pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta); gamma gamma_base; if (theta gamma) || (theta pi_val/3 - gamma) if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end else if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end end HA T0 / single(2); HB T0 / single(2) T1; HC T0 / single(2) T1 T2; case 2 T1 sqrt3 * U / Udc * sin(pi_val - theta); T2 sqrt3 * U / Udc * sin(theta - single(2)*pi_val/3); gamma gamma_base single(2)*pi_val/3; if (theta gamma) || (theta single(5)*pi_val/3 - gamma) if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end else if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T11 - T2; end end HA T0 / single(2) T1 T2; HB T0 / single(2); HC - T0 / single(2) T1; case 3 T1 sqrt3 * U / Udc * sin(single(2)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - pi_val/3); gamma gamma_base pi_val/3; if (theta gamma) || (theta single(3)*pi_val/3 - gamma) if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 - single(0); end else if T1 T2 single(1) scale - single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end end HA T0 / single(2) T2; HB T0 / single(2); HC T0 / single(2) T1 T2; case 4 T1 sqrt3 * U / Udc * sin(singleT5)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - single(4)*pi_val/3); gamma - gamma_base single(4)*pi_val/3; if (theta gamma) || (theta single(9)*pi_val/3 - gamma) if T1_ratio T2_ratio T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 - single(0); end else if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end end HA T0 / single(2) T1; HB T0 / single(2) T1 T2; HC T0 / single(2); case 5 T1 sqrt3 * U / Udc * sin(-theta); T2 sqrt3 * U / Udc * sin(theta - single(5)*pi_val/3); gamma gamma_base single(5)*pi_val/3; if (theta gamma) || (theta single(11)*pi_val/3 - gamma) if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end else if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end end HA T0 / single(2); HB T0 / single(2) T1 T2; HC T0 / single(2) T2; case 6 T1 sqrt3 * U / Udc * sin(single(4)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - pi_val); gamma gamma_base single(3)*pi_val/3; if (theta gamma) || (theta single(7)*pi_val/3 - gamma) if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end else if T1 T2 single(1) scale single(1) / (T1 T2); T1 T1 * scale; T2 T2 * scale; T0 single(0); else T0 single(1) - T1 - T2; end end HA T0 / single(2) T1 T2; HB T0 / single(2) T2; HC T0 / single(2); end end else mode uint8(2); switch Sector case 1 T1 sqrt3 * U / Udc * sin(pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta); if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end HA T0 / single(2); HB T0 / single(2) T1; HC T0 / single(2) T1 T2; case 2 T1 sqrt3 * U / Udc * sin(pi_val - theta); T2 sqrt3 * U / Udc * sin(theta - single(2)*pi_val/3); if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end HA T0 / single(2) T1 T2; HB T0 / single(2); HC T0 / single(2) T1; case 3 T1 sqrt3 * U / Udc * sin(single(2)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - pi_val/3); if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end HA T0 / single(2) T2; HB - T0 / single(2); HC - T0 / single(2) T1 T2; case 4 T1 sqrt3 * U / Udc * sin(single(5)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - single(4)*pi_val/3); if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end HA T0 / single(2) T1; HB T0 / single(2) T1 T2; HC T0 / single(2); case 5 T1 sqrt3 * U / Udc * sin(-theta); T2 sqrt3 * U / Udc * sin(theta - single(5)*pi_val/3); if T1 T2 T1 single(1); T2 single(0); T0 single(0) ; else T1 single(0); T2 single(1); T0 single(0); end HA T0 / single(2); HB T0 / single(2) T1 T2; HC T0 / single(2) T2; case 6 T1 sqrt3 * U / Udc * sin(single(4)*pi_val/3 - theta); T2 sqrt3 * U / Udc * sin(theta - pi_val); if T1 T2 T1 single(1); T2 single(0); T0 single(0); else T1 single(0); T2 single(1); T0 single(0); end HA T0 / single(2) T1 T2; HB T0 / single(2) T2; HC T0 / single(2); end end % ----输出占空比限幅并转为single---- Ua min(max(HA, single(0)), single(1)); Ub min(max(HB, single(0)), single(1)); Uc min(max(HC, single(0)), single(1)); Ua single(Ua); Ub single(Ub); Uc single(Uc); end