if (vlt >= 2.053 && vlt<=2.429) {
      pwm = 1120000*vlt - 599091.53*pow(vlt, 2) + 97270.91*pow(vlt, 3) - 555056.01;
    }
    if (vlt > 2.429 && vlt<=2.9044) {
      pwm = - 1946000*vlt - 663917.686*pow(vlt, 2) - 76052.71*pow(vlt, 3) + 1929000;
    }
    if (vlt > 2.9044 && vlt<=3.023) {
      pwm = 698771.83*vlt - 247841.85*pow(vlt, 2) + 28588.47*pow(vlt, 3) - 624255.9;
    }
    if (vlt >3.023 && vlt<=3.6476) {
      pwm = - 164469.48*vlt + 37815.88*pow(vlt, 2) - 2909.79*pow(vlt, 3) + 244994.92;
    }
    if (vlt > 3.6476 && vlt<=4.391) {
      pwm = -150582.39*vlt + 33363.15*pow(vlt, 2) - 2502.88*pow(vlt, 3) + 233835.97;
    }
    if (vlt > 4.391 && vlt<=5.01) {
      pwm = 8570.55*vlt - 2937.04*pow(vlt, 2) + 252.77*pow(vlt, 3) + 1595.3;
    }
    if (vlt > 5.01 && vlt<=6.573) {
      pwm = - 22131.13*vlt + 3196.08*pow(vlt, 2) - 155.29*pow(vlt, 3) + 52782.94;
    }
    if (vlt > 6.573 && vlt<=7.85) {
      pwm = - 4881.61*vlt + 528.11*pow(vlt, 2) - 19.99*pow(vlt, 3) + 16246.81;
    }
    if (vlt > 7.85 && vlt<=8.47) {
      pwm = - 4009.6*vlt + 418.84*pow(vlt, 2) - 15.35*pow(vlt, 3) + 13890.95;
    }
    if (vlt > 8.47 && vlt<=9) {
      pwm = - 259.69*vlt - 22.28*pow(vlt, 2) + 2.01*pow(vlt, 3) + 3226.53;
    }
    if (vlt > 9 && vlt<=9.86) {
      pwm = - 1293.81*vlt + 92.74*pow(vlt, 2) - 2.25*pow(vlt, 3) + 6322.44;
    }
    if (vlt > 9.86 && vlt<=10.82) {
      pwm = - 1814.92*vlt + 145.12*pow(vlt, 2) - 4.02*pow(vlt, 3) + 8065.16;
    }
    if (vlt > 10.82 && vlt<=11.83) {
      pwm = - 957.15*vlt + 65.6*pow(vlt, 2) - 1.57*pow(vlt, 3) + 4995.5;
    }
    if (vlt > 11.83 && vlt<=12.53) {
      pwm = - 1237.45*vlt + 89.39*pow(vlt, 2) - 2.24*pow(vlt, 3) + 6087.75;
    }
    if (vlt > 12.53 && vlt<=13.8) {
      pwm = 219.25*vlt - 26.77*pow(vlt, 2) + 0.85*pow(vlt, 3) - 6.47;
    }
    if (vlt > 13.8 && vlt<=15.32) {
      pwm = - 2148.01*vlt + 144.64*pow(vlt, 2) - 3.29*pow(vlt, 3) + 10898.28;
    }
    if (vlt > 15.32 && vlt<=17.42) {
      pwm = 3802.48*vlt - 245.08*pow(vlt, 2) + 5.22*pow(vlt, 3) - 19393.05;
    }
    if (vlt > 17.42 && vlt<=19.7) {
      pwm = - 16726.31*vlt + 933.37*pow(vlt, 2) - 17.33*pow(vlt, 3) + 99815.81;
    }
    if (vlt > 19.7 && vlt<=20) {
      pwm = 120936.25*vlt - 6054.6*pow(vlt, 2) + 100.91*pow(vlt, 3) - 804165;
    }