Delta Electronics (shanghai) Co., Ltd

Photonic Technologies (shanghai) Co., Ltd.

Tao Xia

Xuefeng Chen

Xin Wang

Rui Bai

Wenjun He

Patrick Yin Chiang

Shang Hu

Juncheng Wang

Wenzong Pan

Zhichun Wang

Yuanxi Zhang

Cheng Lu

Hong Tao Liu

Wenfei Hu

Chao Yan

Yuan Wx Li

Pei Jiang

Yong Tao

Xinwei Liu

Yifan Wu

Sheng-Hua Li

Kailiang Zhan

Yuwei Wang

Hong Liu

A three-phase converter and a control method thereof are provided. The three-phase converter includes an AC terminal, three filter circuits, three bridge arm circuits, a capacitor module and a DC terminal connected in sequence and a controller. The midpoints of the filter circuits are connected to the midpoint of the capacitor module. The controller controls each bridge arm circuit to work in the first and second modes at different time in one line voltage cycle of the AC source. In the first mode, the bridge arm circuit works in a clamping state. In the second mode, the bridge arm circuit selectively works in a DCM mode or a TCM mode. A switching frequency is limited to be lower than a preset frequency. When the three-phase converter works with over 80% of a rated load, a time length of working in the second mode is &#x2153;&#x2dc;&#x2154; of the line voltage cycle.

Three-phase converter and control method thereof

A three-phase power supply system includes three phase branches forming a delta connection. Each of the phase branches includes at least one power conversion cell of at least two stages. The at least one power conversion cell of each of the phase branches is connected in parallel to the at least one power conversion cell of the respective other two phase branches. When one of the phase branches stops operating, the other two phase branches keep operating, and three phase current of the three-phase power supply system can be balanced by regulating active powers and reactive powers of the other two phase branches. Through the invention, when one of the phase branches stops operating, the other two phase branches may keep operating, and three phase current of the three-phase power supply system are balanced.

Three-phase power supply system and power supply method

Disclosed are three-phase system and distributed control method. The three-phase system comprises three-phase circuits, of which each phase circuit including at least one power conversion cell; and at least three phase controllers for controlling each phase circuit, respectively, each phase controller including a communication interface through which the at least three phase controllers are in communications connection with each other; wherein the phase controllers of each phase circuit is configured for regulating bridge arm voltages of the at least one power conversion cell in the phase circuit by receiving signals sent from the phase controllers of other two phase circuits through the communication interface. The three-phase system and the distributed control method of the invention solve problems of balance of three-phase current and stabilization of three-phase DC voltages by coordination among the three phases. Thanks to the invention, the three phases can be independently controlled to improve control flexibility.

Three-phase system and distributed control method thereof

A laser pulse sampling and detecting circuit includes: a laser driver which is driven by a triggering signal for generating laser pulse signal; a photoelectric converter for converting the laser pulse signal into current pulse signal; an amplifier for amplifying and converting the current pulse signal into voltage pulse signal; an ADC which is driven by a sampling clock signal for sampling the voltage pulse signal and performing analog-to-digital conversion on the voltage pulse signal, so as to obtain output signal of the ADC; a detector for detecting the output signal of the ADC, so as to obtain peak power and FWHM of the laser pulse signal; and a clock generator for generating the sampling clock signal. Phase of the sampling clock signal consecutively changes with respect to the triggering signal.

Laser pulse sampling and detecting circuit, system, and method

A driving and controlling method and a circuit thereof are provided. The method includes: sending, by a primary controller, a first signal that includes a first type of pulse sequence and a second type of pulse sequence; receiving the first signal, by a secondary controller, and identifying a pulse type of the first signal; when a first type of pulse is detected, the secondary controller outputs multiple switching signals to respectively control multiple switching elements to turn off; when a second type of pulse is detected, the secondary controller outputs multiple switching signals to respectively control multiple switching elements to work as normal. A level of the first signal is maintained constant between the first type of pulse sequence and the second type of pulse sequence. The disclosure features cost-efficiency and low driving delay.

Driving and controlling method for switching element and circuit thereof

The present disclosure provides a power electronic conversion unit and a power electronic conversion system. The power electronic conversion unit includes: two AC/DC subunits, AC ports of which are coupled in series to form a first port; two half-bridge subunits, DC ports of which are coupled to DC ports of the two AC/DC subunits, respectively; and a transformer, wherein two terminals of a primary winding of the transformer are coupled to a midpoint of bridge arms of the two half-bridge subunits. And a power electronic conversion system comprises a plurality of power electronic conversion units.

Power electronic conversion unit and system

A method for monitoring capacitance of DC bus capacitor of a power electronic converter is provided, wherein the power electronic converter includes at least one AC/DC conversion circuit and the DC bus capacitor, a power input/output interface of the AC/DC conversion circuit including a first terminal and a second terminal. The first terminal is connected to an AC grid with a frequency of f, the second terminal is connected to the DC bus capacitor, f is any positive real number, and the method includes: measuring a pulsating power with a frequency of 2f flowing through the DC bus capacitor and a voltage on the DC bus capacitor; and calculating the capacitance of the DC bus capacitor based on the pulsating power and the voltage on the DC bus capacitor. An apparatus for monitoring the capacitance of the DC bus capacitor is provided correspondingly.

Method and apparatus for monitoring capacitance of DC bus capacitor

An apparatus comprises a plurality of sampling circuits configured to receive a non-Non Return to Zero (non-NRZ) data signal; and a control circuit coupled to the plurality of sampling circuits, wherein the control circuit is configured to provide one or more control signals indicating whether to decrease or increase a frequency of a clock signal associated with the non-NRZ data signal based on the non-NRZ data signal.

Clock and data recovery circuit

Frequency detector, and clock and data recovery circuit including the frequency detector

Non-transitory machine readable medium for clock recovery

Apparatus and method for clock recovery based on non-non return to zero (non-NRZ) data signals

Frequency detector for clock recovery

Apparatus and method for clock recovery

A method of putting a converter module of a cascade converter system into operation, wherein the cascade converter system includes: n converter modules; n bypass switch modules; and a system controller, wherein the method includes: a module pre-plug-in step: m bypass switch modules of the n bypass switch modules being in a non-bypass state, and remaining n-m bypass switch modules being in a bypass state, the system controller communicating with the module controllers of the m converter modules, such that the m converter modules operate according to a first control signal, wherein 1&#x2264;m&#x3c;n; a module plug-in step: the system controller controls the (m+1)bypass switch module to change from the bypass state to the non-bypass state; and a module post-plug-in step: the system controller communicating with the module controllers of the m+1 converter modules, such that the m+1 converter modules operate according to a second control signal.

Cascade converter system and method of putting converter module of the same into operation

Growing community of inventors

Shanghai, China

Tao Xia