In a parallel DC/DC converter system, Droop Control is a common method to achieve power balance among different modules. In the droop control strategy, the output voltage of each converter will decrease as the load increases, which can ensure that all converters work under the same load, thereby achieving power balance.
The basic principle of droop control can be expressed as: by associating the output voltage of the converter with the load current, when the load increases, the corresponding output voltage drops. In this way, when the load on one converter increases, its output voltage decreases, while other converters connected in parallel with it take on more load due to their higher voltage, thereby achieving a current sharing effect.
When implementing the C language code for droop control, it should be noted that the code here is only a simplified version of the implementation, and the implementation in the real environment may need to consider more complexities, such as ADC (analog-to-digital conversion) reading, PWM (pulse width modulation) control, fault protection, etc. The following is the corresponding C language code:
#include <stdint.h>
// 定义转换器参数
#define K_DROOP 0.05 // 下垂控制系数
#define V_REF 48.0 // 参考电压
// 全局变量
float v_output; // 输出电压
float i_load; // 负载电流
// 读取ADC的函数，用于获取输出电压和负载电流
void read_adc_values() {
// 此处应添加读取ADC的代码，获取v_output和i_load的值
// v_output = ...
// i_load = ...
}
// 控制PWM的函数，用于控制输出电压
void control_pwm(float v_target) {
// 此处应添加控制PWM的代码，调整输出电压至v_target
}
// 下垂控制的主函数
void droop_control() {
while(1) {
// 读取ADC值
read_adc_values();
// 计算目标输出电压
float v_target = V_REF - i_load * K_DROOP;
// 控制PWM以达到目标输出电压
control_pwm(v_target);
}
}
In this code, the parameters of the converter are defined first, and then the functions for reading the ADC value and controlling the PWM are defined. In the main function of the droop control, the ADC value is first read, then the target output voltage is calculated, and finally the target output voltage is reached through PWM control to complete the droop control.
This is just a basic droop control implementation, and various protection mechanisms and fault detection may need to be added in practical applications to ensure the stability and safety of the system.
