摘要:
A three-phase power supply with a three-phase three-level DC/DC converter includes a full-bridge thyristor converter with three-set four in-series power switch elements, a three-phase isolated transformer, a full-bridge rectifier, a rectifying circuit, and a low-pass filtering circuit. The three-phase power supply is used to deliver power energy from the AC input voltage to the load. The power switch elements, which separated to each other at 120-degree phase differences, are controlled through a phase shift scheme. Therefore, the three-level circuit structure is provided to reduce withstanding voltage of the power switch elements, further the zero-voltage switching (ZVS) is achieved by the isolated transformer and the power switch elements to increase the efficiency of the DC/DC converter.
摘要:
A three-phase power supply with a three-phase three-level DC/DC converter includes a full-bridge thyristor converter with three-set four in-series power switch elements, a three-phase isolated transformer, a full-bridge rectifier, a rectifying circuit, and a low-pass filtering circuit. The three-phase power supply is used to deliver power energy from the AC input voltage to the load. The power switch elements, which separated to each other at 120-degree phase differences, are controlled through a phase shift scheme. Therefore, the three-level circuit structure is provided to reduce withstanding voltage of the power switch elements, further the zero-voltage switching (ZVS) is achieved by the isolated transformer and the power switch elements to increase the efficiency of the DC/DC converter.
摘要:
A photovoltaic powered system and an alternating current (AC) module thereof are disclosed. The photovoltaic powered system provides a direct current (DC) power through a photovoltaic module and converts the DC power into an AC power, which is grid-connected to an AC utility power. The AC module of the photovoltaic powered system produces a continuous quasi-sinusoidal current and the quasi-sinusoidal current is converted into a sinusoidal current. The high-frequency harmonic components of the sinusoidal current are filtered to produce a sinusoidal output current in phase with the AC utility power, thus realizing the maximum power point tracking (MPPT) of the photovoltaic module and feeding unity-power-factor power into the AC utility power.
摘要:
A high-efficiency high step-up ratio direct current converter with an interleaved soft-switching mechanism is provided. The direct current converter includes a voltage-multiplier circuit and an active clamping circuit. The voltage-multiplier circuit includes two isolating transformers, two main switches disposed on a primary side of the two isolating transformers, four diodes disposed on a secondary side of the two isolating transformers and four capacitors disposed on the secondary side of two isolating transformers, configured to boost a voltage of a direct-current power to a desired voltage value. The active clamping circuit, electrically connected to the voltage-multiplier circuit, includes two active clamp switches and a clamp capacitor to lower a voltage surge of the two main switches so that the two main switches and the two active clamp switches can be soft switched on.
摘要:
A photovoltaic powered system and an alternating current (AC) module thereof are disclosed. The photovoltaic powered system provides a direct current (DC) power through a photovoltaic module and converts the DC power into an AC power, which is grid-connected to an AC utility power. The AC module of the photovoltaic powered system produces a continuous quasi-sinusoidal current and the quasi-sinusoidal current is converted into a sinusoidal current. The high-frequency harmonic components of the sinusoidal current are filtered to produce a sinusoidal output current in phase with the AC utility power, thus realizing the maximum power point tracking (MPPT) of the photovoltaic module and feeding unity-power-factor power into the AC utility power.
摘要:
A high-efficiency high step-up ratio direct current converter with an interleaved soft-switching mechanism is provided. The direct current converter includes a voltage-multiplier circuit and an active clamping circuit. The voltage-multiplier circuit includes two isolating transformers, two main switches disposed on a primary side of the two isolating transformers, four diodes disposed on a secondary side of the two isolating transformers and four capacitors disposed on the secondary side of two isolating transformers, configured to boost a voltage of a direct-current power to a desired voltage value. The active clamping circuit, electrically connected to the voltage-multiplier circuit, includes two active clamp switches and a clamp capacitor to lower a voltage surge of the two main switches so that the two main switches and the two active clamp switches can be soft switched on.