反激MOS管上的波形分析，反激工作原理-Waveform analysis on flyback MOSFET, flyback working principle.

Of the many converter topologies around today, the flyback topology is one of the most frequently used. Although simple, this converter design offers great advantages for certain applications. New, more complex topologies have surfaced in recent years, but flyback converters remain a popular design choice.

Operating Modes

 Like other converters a yback converter has two operating modes; continuous conduction mode (CCM) and discontinuous conduction mode (DCM). The two operation modes have dierent transfer equations and dierent current and voltage wave forms. Therefore, from a design point of view it is important to analyse the current and voltage that the electric components in the converter experience. Particularly the current owing through the circuit, voltage across the switch and the diode [2]. The magnetizing inductance and the load current determines the operation mode of the converter. During the analysis of the dierent conduction modes of the converter, the following assumptions will be made [5].  The converter is operating in steady state  The converter is ideal, that is the input power is equal to the output power  Leakage inductance, stray capacitors and stray resistances are neglected.

전압 직렬보상 방식 디지털 제어 교류 저전압보상기 정 강 률* Digital-Controlled AC Low-Voltage Compensator with Voltage Series Compensation Method Gang-Youl Jeong*

 

전압 직렬보상 방식 디지털 제어 교류 저전압보상기 정 강 률* Digital-Controlled AC Low-Voltage Compensator with Voltage Series Compensation Method Gang-Youl Jeong* Journal of KIIT. Vol. 21, No. 12, pp. 87-98, Dec. 31, 2023. pISSN 1598-8619, eISSN 2093-7571 87 

 Abstract 

This paper presents the digital-controlled AC low-voltage compensator with voltage series compensation method. The proposed AC low-voltage compensator compensates for the magnitude of the AC load input voltage, which is the final output voltage, with the voltage series compensation method using a power circuit topology consisting of a pulse-width modulation(PWM) AC-AC power converter and a compensating transformer. To this end, the proposed low-voltage compensator simply feeds back the magnitude of AC load input voltage through a circuit consisting of a current-type voltage transformer, a diode full-bridge rectifier, and a resistor/capacitor. Additionally, using a micom, it converts the feedback voltage to a digital value through A/D conversion and easily controls the entire system. This paper first briefly describes the operating principle of the power converter applied to the proposed low-voltage compensator and explains the control method of low-voltage compensation and the feedback method of final output voltage. Then, the driving method of the bidirectional power semiconductor switch of power converter is explained, and the implementation feasibility and good operating characteristics of the proposed low-voltage compensator are validated through the experimental results of the prototype.

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단일단 교류 전력변환기를 이용한 자동 교류 전압조정기-Automatic AC Voltage Regulator using the Single-Stage AC Power Converter Gang-Youl Jeong*

 

단일단 교류 전력변환기를 이용한 자동 교류 전압조정기 정 강 률* Automatic AC Voltage Regulator using the Single-Stage AC Power Converter Gang-Youl Jeong* Journal of KIIT. Vol. 20, No. 11, pp. 73-83, Nov. 30, 2022. pISSN 1598-8619, eISSN 2093-7571 73 

 Abstract 

This paper presents the automatic AC voltage regulator using the single-stage AC power converter. The proposed automatic AC voltage regulator uses a pulse-width modulation(PWM) type non-isolated single-stage step-up/down AC power converter to control and maintain the level of AC voltage on the output-side to a desired level. Since the proposed voltage regulator controls the magnitude of output voltage by using only the average of the scaling values of the output voltage fed back by a simple voltage feedback circuit without phase synchronization, the control method of output voltage is simple. Thus, the proposed voltage easily controls the entire system using a single-chip microcontroller. In this paper, first, the operating principle of the power converter of proposed voltage regulator is briefly explained, and then the feedback and control method of output voltage are described. The feasibility and operating characteristics of proposed voltage regulator are verified through the experimental results of prototype. The proposed voltage regulator can control and maintain the output-side AC voltage to a desired level by performing the step-up/down control operation accurately, and shows a fast dynamic response characteristic.

VIEW FULL TEXT: https://ki-it.com/xml/34783/34783.pdf