Abstract: A bypass seamless switching apparatus and a method thereof are provided, in which a controller sends a first control signal to control or switch a first relay to on/off state, sends a second control signal to control or switch a second relay to on/off state, and sends a switch signal to control or switch a bypass switch module to on/off state. When the controller is in failure mode or is disconnected, a driving power supply of a bypass circuit provides a driving signal to the bypass switch module to maintain or switch a switch of the bypass switch module to on state, so that the bypass switch module is in short-circuit state or short-circuit protection state, and a bypass side voltage of the bypass switch module is equal to or close to zero voltage, so as to execute bypass function or bypass seamless switching function of the bypass switch module.

Abstract: A sensorless measurement device for filter capacitor current by using a state observer is provided. The sensorless measurement device comprises a chip, wherein the chip comprises the state observer. The state observer is configured to retrieve a filter-capacitor-voltage actual value and a direct current link (dc-link) voltage of a present sampling time. According to the filter-capacitor-voltage actual value and the dc-link voltage, the state observer is configured to output a filter-capacitor-voltage state variable value, a filter-capacitor-current state variable value, and a disturbance-voltage state variable value of a next sampling time. The filter-capacitor-current state variable value is an average current value without ripples.

Abstract: A ripple-compensation control method and electrical energy conversion device utilizing the same are provided. The ripple-compensation control method is disclosed, adopted by an electrical energy conversion device including a converter configured to perform electrical energy conversion, a controller coupled to control terminals of the converter and controlling a first voltage of a DC node of the converter according to a command value, and a ripple-compensation unit configured to generate a ripple-component voltage of the first voltage and provide the command value generated based on the ripple-component voltage to the controller.

Abstract: A sensorless measurement device for filter capacitor current by using a state observer is provided. The sensorless measurement device comprises a chip, wherein the chip comprises the state observer. The state observer is configured to retrieve a filter-capacitor-voltage actual value and a direct current link (dc-link) voltage of a present sampling time. According to the filter-capacitor-voltage actual value and the dc-link voltage, the state observer is configured to output a filter-capacitor-voltage state variable value, a filter-capacitor-current state variable value, and a disturbance-voltage state variable value of a next sampling time. The filter-capacitor-current state variable value is an average current value without ripples.

Abstract: A voltage compensating method is applied to a converter for converting a DC voltage into an AC voltage. The converter includes a first switch module, a second switch module, and an inductor. In a first dead time period, detect a first current value related to the inductor. According to the first current value, calculate a second current value and a third current value related to the inductor. According to polarities of the first, second and third current values, determine an output mode of the converter indicating a voltage compensation model after the first dead time period. According to the voltage compensation model, the first current value, and the second current value or the third current value, calculate a voltage compensation value. In a second dead time period, adjust a switching time for the first switch module and the second switch module according to the voltage compensation value.

Abstract: A ripple-compensation control method and electrical energy conversion device utilizing the same are provided. The ripple-compensation control method is disclosed, adopted by an electrical energy conversion device including a converter configured to perform electrical energy conversion, a controller coupled to control terminals of the converter and controlling a first voltage of a DC node of the converter according to a command value, and a ripple-compensation unit configured to generate a ripple-component voltage of the first voltage and provide the command value generated based on the ripple-component voltage to the controller.

Abstract: A voltage compensating method is applied to a converter for converting a DC voltage into an AC voltage. The converter includes a first switch module, a second switch module, and an inductor. In a first dead time period, detect a first current value related to the inductor. According to the first current value, calculate a second current value and a third current value related to the inductor. According to polarities of the first, second and third current values, determine an output mode of the converter indicating a voltage compensation model after the first dead time period. According to the voltage compensation model, the first current value, and the second current value or the third current value, calculate a voltage compensation value. In a second dead time period, adjust a switching time for the first switch module and the second switch module according to the voltage compensation value.

Abstract: A full-bridge quasi-resonant DC-DC converter is provided, including a transformer having a primary winding and a secondary winding, a full-bridge converting circuit electrically connected with the primary winding of the transformer, a resonant capacitor provided between the full-bridge converting circuit and the primary winding, a rectifier circuit electrically connected with the secondary winding of the transformer, and a resonant inductor connected in series with the rectifier circuit. Therefore, the full-bridge quasi-resonant DC-DC converter reduces the switching losses of the switching elements and effectively reduces the size of the converter, while increases the conversion efficiency.

Abstract: The disclosure provides an interlocking device and a three-phase interlocking device for a DC to AC converter (DAC). The interlocking device includes a first interlocking circuit and a second interlocking circuit. The first interlocking circuit couples with a first switch and a second switch, controls whether to conduct the first switch according to the logic levels of a first signal, a second signal and a third signal, and controls whether to conduct the second switch according to the logic levels of the first signal and the second signal. The second interlocking circuit couples with a third switch and a fourth switch, controls whether to conduct the third switch according to the logic levels of the first signal, the third signal and a fourth signal, and controls whether to turn on the fourth switch according to the logic levels of the third signal and the fourth signal.

Abstract: The disclosure provides an interlocking device and a three-phase interlocking device for a DC to AC converter (DAC). The interlocking device includes a first interlocking circuit and a second interlocking circuit. The first interlocking circuit couples with a first switch and a second switch, controls whether to conduct the first switch according to the logic levels of a first signal, a second signal and a third signal, and controls whether to conduct the second switch according to the logic levels of the first signal and the second signal. The second interlocking circuit couples with a third switch and a fourth switch, controls whether to conduct the third switch according to the logic levels of the first signal, the third signal and a fourth signal, and controls whether to turn on the fourth switch according to the logic levels of the third signal and the fourth signal.

Abstract: A full-bridge quasi-resonant DC-DC converter is provided, including a transformer having a primary winding and a secondary winding, a full-bridge converting circuit electrically connected with the primary winding of the transformer, a resonant capacitor provided between the full-bridge converting circuit and the primary winding, a rectifier circuit electrically connected with the secondary winding of the transformer, and a resonant inductor connected in series with the rectifier circuit. Therefore, the full-bridge quasi-resonant DC-DC converter reduces the switching losses of the switching elements and effectively reduces the size of the converter, while increases the conversion efficiency.