Current Hysteresis Comparison Method

The Current Hysteresis Comparison Method is a widely used current regulation technique in motor drives and power electronics control systems. Its core principle involves setting upper and lower current thresholds (hysteresis band) to compare actual current with target current, thereby controlling the switching states of power semiconductor devices to achieve fast current tracking and regulation.

In implementation, the method requires real-time current signal sampling and comparison with the reference current value. When the actual current exceeds the target current plus the upper hysteresis limit, the controller turns off the power switching devices; when the actual current falls below the target current minus the lower hysteresis limit, the controller reactivates the switches. This control strategy effectively minimizes current ripple and enhances system dynamic response, making it suitable for high-performance current control applications like inverters and motor drives.

The method is typically combined with PWM (Pulse Width Modulation) technology, where switching frequency and hysteresis band adjustments can optimize current tracking accuracy and efficiency. In practical applications, hysteresis bandwidth selection is critical—too wide a band increases current ripple, while too narrow a band may cause excessive switching frequency and higher system losses. Code implementation often involves ADC (Analog-to-Digital Converter) interrupts for current sampling and comparator functions with dead-time management to prevent shoot-through.

For development environments like version 7.0, ensure high current sampling accuracy and real-time performance, with proper configuration of hysteresis parameters to maintain stable closed-loop current control. Key programming considerations include implementing anti-aliasing filters for analog signals and using timer-based PWM generation with hysteresis comparators in the control algorithm.