Delta Electronics, Inc.

Yi-Ping Hsieh

Hung-Chieh Lin

Jin-Zhong Huang

Chao-Li Kao

Chao-Lung Kuo

Hung-Yu Huang

Hsin-Chih Chen

Chih-Hsien Li

Po-Hsin Tseng

Ciao-Yin Pan

Li-Hung Wang

Yuan-Fang Lai

Jen-Chuan Liao

Hong-Wen Chen

Meng-Jiang Tsai

Chang-Ye Li

Chien-Shien Lee

A dual power switching system selects a first power source or a second power source to supply power to a load coupled to an inductive device. The dual power switching system includes a first thyristor, a second thyristor, a third thyristor, a fourth thyristor, and a controller. The controller calculates a total magnetic flux according to a current magnetic flux of the inductive device and an expected magnetic flux of the second power source. When the power-supplying source is switched, the controller turns off the first thyristor and the second thyristor, and determines whether a commutable time is reached according to a power parameter of the first static transfer switch and the second static transfer switch. When the commutable time is reached, the controller correspondingly turns on at least one of the third thyristor and the fourth thyristor according to the total magnetic flux being less than a threshold.

Dual power switching system and method of operating the same

A circulating current suppression method of a power system having a plurality of power modules is provided. Each power module includes a high-voltage bus, a low-voltage bus and a balance circuit having a neutral voltage. The circulating current suppression method includes: in each balance circuit, disposing a first capacitor electrically coupled between the high-voltage bus and the neutral voltage, and disposing a second capacitor electrically coupled between the neutral voltage and the low-voltage bus; acquiring a current effective value of an input of each power module; if detecting that the current effective value of at least one power module doesn't remain at a current reference value, determining that a circulating current occurs in the at least one power module; and operating the balance circuit of the at least one power module to charge the first capacitor or the second capacitor to regulate the neutral voltage for suppressing the circulating current.

Power system and circulating current suppression method thereof

A power converter and a power conversion method are provided and capable of bus capacitor voltage balance based on inherent inductor components of the power converter. Compared with the conventional approach that adds a balance circuit, the power converter and the power conversion method can reduce a size of overall circuit and improve a power density. In addition, two relays of the power converter are configured to switch switching states such that two inductors store or release energy, thereby transmitting electrical energy between two bus capacitors and two load capacitors. The power converter and the power conversion method are able to realize energy balance and hybrid power supply and satisfy various load requirements.

Power converter and power conversion method

A power converter is provided. The power converter includes first to fourth switches electrically connected in series, a flying capacitor and a controller. Positive and negative terminals of the flying capacitor are electrically connected to the second and third switches respectively. The controller operates the first and fourth switches to perform a first complementary switching with a first dead time, and operates the second and third switches to perform a second complementary switching with a second dead time. The controller determines to regulate the first or second dead time by detecting a capacitor voltage of the flying capacitor, such that the capacitor voltage of the flying capacitor is maintained within a balance voltage range.

Power converter and multi-level power conversion system

A soft-switching power converter includes a main switch, an energy-releasing switch, and an inductive coupled unit. The main switch is a controllable switch. The energy-releasing switch is coupled to the main switch. The inductive coupled unit is coupled to the main switch and the energy-releasing switch. The inductive coupled unit includes a first inductance, a second inductance coupled to the first inductance, and an auxiliary switch unit. The auxiliary switch unit is coupled to the second inductance to form a closed loop. The main switch and the energy-releasing switch are alternately turned on and turned off. The auxiliary switch unit is controlled to start turning on before the main switch is turned on so as to provide at least one current path.

Soft-switching power converter

An uninterruptible power apparatus is coupled between a power grid and a load. The uninterruptible power apparatus includes a bypass path, a power conversion module, and a control module. The bypass path is coupled to the power grid through a grid terminal, and coupled to the load through a load terminal. The control module turns off a first thyristor and a second thyristor by injecting a second voltage into the load terminal during a forced commutation period. The control module calculates a magnetic flux offset amount based on an error amount between the second voltage and a voltage command, and provides a compensation command in response to the magnetic flux offset amount. The control module controls the DC/AC conversion circuit to provide a third voltage to the load terminal based on the compensation command and the voltage command.

Uninterruptible power apparatus and magnetic flux compensation method thereof

An isolated conversion apparatus with magnetic bias balance control includes an isolated converter, a controller, and a magnetic bias balance circuit. The isolated converter includes a transformer, and a primary side of the transformer includes a primary-side winding and at least one switch bridge arm. The controller is coupled to the at least one switch bridge arm, and provides a pulse width modulation (PWM) signal group to control the at least one switch bridge arm. The magnetic bias balance circuit is coupled to two ends of the primary-side winding and the controller, and provides a compensation voltage to the controller according to an average voltage of a winding voltage across the two ends of the primary-side winding. The controller adjusts a duty cycle of the PWM signal group according to the compensation voltage to correct the magnetic bias.

Isolated conversion apparatus with magnetic bias balance control and method of controlling the same

A ground fault detection apparatus is used to detect a ground fault of a three-phase UPS apparatus. The UPS apparatus includes a first filter circuit, an AC/DC conversion circuit, a DC bus, a DC/AC conversion circuit, and a second filter circuit coupled in sequence. The ground fault detection apparatus includes a detection circuit having a first detection end and a second detection end. The first detection end is coupled to the first filter circuit and the second filter circuit, and the second detection end is coupled to an equipment grounding point. The equipment grounding point is coupled to a neutral point of a three-phase power source, and the three-phase power source is coupled to the first filter circuit. The detection circuit indicates whether the UPS apparatus has a ground fault and a location where the ground fault occurs according to a detection voltage between the first detection end and the second detection end.

Ground fault detection apparatus and method of detecting ground fault

An isolated converter with high boost ration includes a transformer, a first bridge arm, a second bridge arm, and a boost circuit. The transformer includes a secondary side having a secondary side first node and a secondary side second node. The first bridge arm includes a first diode and a second diode. The second bridge arm includes a third diode and a fourth diode. The boost circuit includes at least one fifth diode coupled between the first bridge arm and the secondary side second node, at least one sixth diode coupled between the second bridge arm and the secondary side first node, and at least two capacitors coupled to the secondary side first node and the secondary side second node.

Isolated converter with high boost ratio

An uninterruptible power apparatus with a function of forced disconnection path is coupled between a grid and a load, and the uninterruptible power apparatus includes a bypass path, a power conversion module, a current detection unit, and a control module. The bypass path includes a switch unit, and the power conversion module is connected in parallel to the bypass path. The current detection unit detects a current flowing through the bypass path and transmits a current signal to the control module. The control module provides a turned-off signal to the switch unit when a first voltage of the grid is abnormal, and transmits a polarity of the current signal. The power conversion module generates a compensation amount according to the polarity, and generates an output voltage command according to the compensation amount and a voltage at an input terminal or an output terminal of the power conversion module.

Uninterruptible power apparatus with function of forced disconnection path and method of forcing disconnection path thereof

A conversion apparatus with a three-level switching circuit includes a DC conversion module, a three-level circuit, and a control unit. The three-level circuit includes a bridge arm assembly and a capacitor assembly. The capacitor assembly includes a first capacitor and a second capacitor connected to the first capacitor in series. The DC conversion module has a positive output end and a negative output end, and the positive output end and the negative output end are coupled to the bridge arm assembly. The control unit controls the switching of a second switch unit and a third switch unit to make the three-level circuit operate in a first state where the positive output end and the negative output end are connected to the first capacitor, and operate in a second state where the positive output end and the negative output end are connected to the second capacitor.

Conversion apparatus with three-level switching circuit and method of operating the same

A method for operating a power factor correction (PFC) circuit of an uninterruptible power supply (UPS) apparatus is provided. The PFC circuit includes two T-type converters, and each of the T-type converters includes four switching tubes. The method includes: converting AC input voltage into a positive bus voltage across a first capacitor and a negative bus voltage across a second capacitor that is connected in series with the first capacitor when the UPS apparatus is operated under a normal supply mode; and controlling conduction states of the switching tubes of the T-type converters to balance the positive bus voltage and the negative bus voltage when the UPS apparatus is operated under a battery supply mode.

Method for operating power factor correction circuit and method for operating uninterruptible power supply apparatus

A power converter with a common DC power source includes a DC power source and at least two power modules. Each of the power modules is coupled with each other and coupled to the DC power source. Each of the power module includes a coupled inductive component coupled to the DC power source, a DC output conversion unit coupled to the coupled inductive component, and a capacitor group having a coupling point. By using the coupled inductive component, it is to solve the problem of return current between the power modules caused by coupling multiple coupling points to each other.

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Taoyuan, Taiwan

Yi-Ping Hsieh