Abstract: A DC-AC inverter system using a state observer and a control method thereof are provided. The control method of the DC-AC inverter system includes the following steps. The state observer outputs a filter-capacitor-current estimation value at a next sampling time according to a DC link voltage at a current sampling time and a filter-capacitor-voltage actual value at the current sampling time. The filter-inductor-current estimation value at the next sampling time is compared with the filter-capacitor-current estimation value at the next sampling time to obtain a load current estimation value at the next sampling time. An inductor voltage estimator outputs a filter-inductor-voltage estimation value at the next sampling time according to the load current estimation value at the next sampling time. A feed-forward control is performed according to the filter-inductor-voltage estimation value at the next sampling time.

Abstract: A DC-AC inverter system using a state observer and a control method thereof are provided. The control method of the DC-AC inverter system includes the following steps. The state observer outputs a filter-capacitor-current estimation value at a next sampling time according to a DC link voltage at a current sampling time and a filter-capacitor-voltage actual value at the current sampling time. The filter-inductor-current estimation value at the next sampling time is compared with the filter-capacitor-current estimation value at the next sampling time to obtain a load current estimation value at the next sampling time. An inductor voltage estimator outputs a filter-inductor-voltage estimation value at the next sampling time according to the load current estimation value at the next sampling time. A feed-forward control is performed according to the filter-inductor-voltage estimation value at the next sampling time.

Abstract: A dead-time voltage compensation apparatus and a dead-time voltage compensation method are provided. The method includes: converting a DC voltage of an input end of a single-phase DC-AC inverter into a unipolar AC voltage; calculating first to third current values based on a first inductor current value of a inductor, calculating first voltage compensation amounts of a first dead-time and a third dead-time of an AC voltage and a second inductor current value of the AC voltage based on polarities of the first to third current values, calculating fourth to sixth current values based on the second inductor current value, calculating second voltage compensation amounts of a second dead-time and a fourth dead-time of the AC voltage based on polarities of the fourth to sixth current values, and compensating a control reference signal of a processor based on the first and second voltage compensation amounts.

Abstract: A dead-time voltage compensation apparatus and a dead-time voltage compensation method are provided. The method includes: converting a DC voltage of an input end of a single-phase DC-AC inverter into a unipolar AC voltage; calculating first to third current values based on a first inductor current value of a inductor, calculating first voltage compensation amounts of a first dead-time and a third dead-time of an AC voltage and a second inductor current value of the AC voltage based on polarities of the first to third current values, calculating fourth to sixth current values based on the second inductor current value, calculating second voltage compensation amounts of a second dead-time and a fourth dead-time of the AC voltage based on polarities of the fourth to sixth current values, and compensating a control reference signal of a processor based on the first and second voltage compensation amounts.

Abstract: A DC-AC converter is provided. The DC-AC converter includes a time-varying DC power generating circuit, an AC power generating circuit and a transmission capacitor. The time-varying DC power generating circuit is controlled by a pulse width modulation (PWM) signal to transform a DC source into a time-varying DC power. With reference to the time-varying DC power, the AC power generating circuit is controlled by a first polarity switching and a second polarity switching signal to generate an AC power. The transmission capacitor, coupled to the time-varying DC power generating circuit and the AC power generating circuit, transmits the time-varying DC power from the time-varying DC generating circuit to the AC power generating circuit.

Abstract: A DC-AC converter is provided. The DC-AC converter includes a time-varying DC power generating circuit, an AC power generating circuit and a transmission capacitor. The time-varying DC power generating circuit is controlled by a pulse width modulation (PWM) signal to transform a DC source into a time-varying DC power. With reference to the time-varying DC power, the AC power generating circuit is controlled by a first polarity switching and a second polarity switching signal to generate an AC power. The transmission capacitor, coupled to the time-varying DC power generating circuit and the AC power generating circuit, transmits the time-varying DC power from the time-varying DC generating circuit to the AC power generating circuit.

Abstract: The AC power generated by AC utility has been successfully transferred from AC-to-DC by means of an AC-to-DC converting circuit. This disclosure provides an AC-to-DC converting circuit applicable to a power-charging module, and the AC-to-DC converting circuit comprises two parts such as a first stage being a low-frequency AC to high-frequency AC converter comprising an input full-bridge rectifier, a full-bridge inverter and an immittance conversion circuit and a second stage being an AC-to-DC converter comprising a single-phase transformer and a full-bridge rectifier, where the inverter in the first stage is switched at high frequencies so as to reduce the size of the transformer in the second stage. Additionally, the immittance conversion circuit is further characterized in voltage to current conversion so as to simplify the control mechanism of the power-charging module, reduce the number of current measuring elements and the cost thereof.