Analog Devices Global

Analog Devices International Unlimited Company

Analog Devices Global Unlimited Company

Analog Devices Technology

Shanghai Power Equipment Research Institute Co., Ltd.

Zhijie Zhu

Liuqing Yang

Jun Jiang

Lin Zhang

Bin Shao

Junxiao Chen

Renjian Xie

Xudong Huang

Basa Wang

Jingwen Mao

Jun Duan

Zifang Zhu

Wangren Xu

Yuxuan Wang

Xinxuan Kong

Chengyi Zhang

Luyi Jiang

Jian Ye

Yuesheng Xie

Xuefei Fan

Jinyuan Shi

Described herein is a spur-free technique for a switching regulator. The switching regulator may self-adaptively reduce the spur of the output voltage without affecting performance of the switching frequency, The switching regulator may track a coil current and may use an active feedback loop to adaptively generate an artificial coil current, which tracks an amplitude of the coil current but having opposite phase. The artificial coil current may then be injected into an output node to cancel the coil current ripple.

Spur free switching regulator with self-adaptive cancellation of coil current ripple

The present disclosure provides a method of multi-objective and multi-dimensional online joint monitoring for a nuclear turbine. The method includes: obtaining first temperature monitoring data of the nuclear turbine by performing online thermal monitoring on a rotor, a valve cage and a cylinder of the nuclear turbine under quick starting-up; obtaining second temperature monitoring data of tightness of a flange association plane of the cylinder of the nuclear turbine by performing online thermal monitoring on the tightness of the flange association plane; obtaining operation monitoring data of a shafting vibration of a rotor and bearing system of the nuclear turbine by performing online safety monitoring on the shafting vibration of the rotor and bearing system; and optimizing operation and maintenance control of the nuclear turbine according to at least one type of monitoring data among the first temperature monitoring data, the second temperature monitoring data and the operation monitoring data.

Method of multi-objective and multi-dimensional online joint monitoring for nuclear turbine

The subject disclosure provides for utilizing pulse width modulation (PWM) signaling to influence a closed loop of a shunt boost controller and reduce an imbalance of a load. The imbalance reduction helps reduce remanence of a current transformer (CT) and thereby prevent saturation of the CT. A shunt boost controller provides the control signal to control flow of current to the load. A feedback network provides a feedback signal to the shunt boost controller based on a direct current (DC) voltage and causes a power switch circuit to turn on when a magnitude of the feedback signal exceeds a threshold magnitude. The PWM generator supplies a PWM signal to cause the control signal to be provided more symmetrical to the power switch circuit and causes the power switch circuit to turn on more frequently with the control signal to reduce the imbalance of the load.

Saturation prevention of current transformer

A power converter can include an electrical isolation circuit between input and output nodes. An input signal monitor node can be provided, such as on a converter output side of the isolation circuit. In an example, a peak detection circuit can be coupled to the input signal monitor node. The output node of the power converter can be configured to supply an output power signal that is a function of an input signal at the input node. The power converter can include multiple, independently-switchable switches at one or more of the input and output sides of the isolation circuit. In an example, the power converter with the input signal monitor node can be configured as a bias supply to provide power, at the output node, to a controller circuit for a main stage power converter circuit.

Isolated power supply with input voltage monitor

An apparatus comprises a switching circuit, an error amplifier circuit, a current threshold circuit, and an over-current detection circuit. The switching circuit provides a switching duty cycle that includes a charge portion and a discharge portion. The error amplifier circuit generates an error signal representative of a difference between a target voltage value and a voltage at an output of the voltage regulator circuit. The switching circuit adjusts the switching duty cycle to regulate the voltage at the output using the error signal and a reference waveform signal. The current threshold circuit generates an adaptive peak current limit threshold. The over-current detection circuit generates an over-current signal when the reference waveform signal satisfies the adaptive peak current limit threshold during the charging portion of the switching cycle. The switching circuit interrupts one or more switching cycles when the reference waveform signal satisfies the adaptive peak current limit threshold.

Emulated peak current limit scheme for switching regulator

Apparatus and methods for generating a drive signal of a switching signal are disclosed. A first circuit receives an oscillating reference signal, a first compensation signal, a second compensation signal, and a third compensation signal. The first compensation signal is indicative of an error between an output voltage of a power converter and a reference voltage. The second compensation signal is indicative of the error relative to a threshold. The third compensation signal is indicative of an output current of the power converter. The first circuit generates a comparison signal having a waveform including pulses having durations based at least partly on a combination of the periodic reference signal, the first compensation signal, the second compensation signal, and the third compensation signal. A second circuit receives a clock signal and the comparison signal and generates a drive signal for activation and deactivation of a driver transistor.

Apparatus and methods for transient compensation of switching power regulators

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Shanghai, China

Zhijie Zhu