占空比与有效电流的关系
The relationship between duty cycle and effective current is primarily manifested in pulse width modulation (PWM) technology. By altering the duty cycle of the RWM signal, the effective value of the output voltage can be controlled. For instance, when the duty cycle is 50%, the effective value of the output voltage is 50% of the input voltage; when the duty cycle is 100%, the effective value of the output voltage equals the input voltage. 

For 24V system，The calculation method for the current of a proportional valve coil with an internal resistance of 20 ohms under different duty cycles can be equivalent to: when the duty cycle is 20%, the coil current = 24.2 * 20% (duty cycle) / 20 (coil internal resistance) = 0.24A = 240ma; (rough calculation)

When the duty cycle is 50%, the coil current = 24.2 * 50% (duty cycle) / 20 (coil internal resistance) = 0.6A = 600ma; (rough calculation)

When the duty cycle is 99%, the coil current = 24.2 * 99% (duty cycle) / 20 (coil internal resistance) = 1.197A = 1197ma; (rough calculation)