Means and associated methods for digitally controlling converter systems

A method for digitally controlling a converter system, comprising:

• generating a digital error signal according to an output voltage of the converter system and a reference voltage;
• generating a duty-cycle signal according to a digital reference signal and the digital error signal;
• and
• generating a PWM signal according to the digital duty-cycle signal in order to control the output voltage of the converter system;
• wherein generating a digital duty-cycle signal further comprises:
• detecting the system status and generating a system status signal according to the digital error signal and the digital reference signal;
• generating a system error signal according to the system status signal and the digital error signal;
• and
• generating the digital duty-cycle signal according to the system error signal;
• wherein detecting the system status and generating a system status signal comprises:
• generating a steady state signal if the system is at a first condition;
• and
• generating a dynamic state signal if an absolute difference between two digital error signals at two latest successive moments is larger than a second predetermined value.

A converter system, comprising:

• a converter circuit, comprising a switch, wherein the converter circuit is configured to generate an output voltage;
• a controller, comprising:
• a digital error signal generator, configured to generator a digital error signal according to the output voltage and a reference voltage;
• a digital control signal generator, configured to generate a digital control signal according to the digital error signal and a digital reference signal;
• and
• a digital modulation module, configured to generate a modulation signal to the switch to regulate the output voltage;
• wherein the digital control signal generator further comprises:
• a system status detector;
• a system error generator, configured to output the digital error signal when the system status signal is in the first status and output zero when the system status signal is in the second status;
• and
• a digital duty-cycle generator, configured to output real-time duty cycle signal and a constant duty-cycle signal according to the output of the system error generator;
• wherein the system status detector is configured to generate:
• a steady state signal as the system status signal at a first status;
• and
• a dynamic state signal as the system status signal at a second status;
• wherein the second status is that an absolute difference between two digital error signals at two latest successive moments is larger than a second predetermined value.