Author: Vijay
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Phase-shift control Method
In this control, the duty cycle varies by phase-shifting the PWM pulses respect to each-other with fixed frequency and turn-on time of each pulse. duty = Function (phase-shift) Full-bridge Inverter: In general, normal full-bridge inverter shown below which is also called as 2-leg converter consist of 4 switches. Leg-1 switches : S1, S4 Leg-2 switches…
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PWM Control Methods
The control methods are important and crucial for sensitive sources and sensitive loads. When we design a converter for a particular input/output voltages and load, whenever change in the source voltage or output reference value or load that connected to converter, we need to give exact output voltage value as per the set reference value.…
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Operation of Phase-shift full-bridge converter (PSFB)
The PSFB circuit with the phase-shift PWM control method can be divided into 10 operating modes. The typical operating signals and waveforms are given below. Mode-1 (t0 -t1): Duty cycle loss mode Mode-2 (t1 – t2): Power Delivery Mode Mode-3 (t2 – t3): Dead Zone Mode After capacitors fully charge and discharge, the discharged capacitor…
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Phase-shift Full-bridge Converter with Center-tapped transformer for step-down applications
Circuit Description The circuit diagram is shown below. It is a combination of full-bridge inverter (DC-AC), high-frequency transformer, and full-wave rectifier (AC-DC) with diodes DC input is given to full-bridge inverter which converts the DC to high frequency (HF) AC –> HF AC is goes to HF transformer and it stepup/stepdown as per design requirement…
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Phase-shift Full-bridge (PSFB) Resonant Converter Topologies in EV charger
These are the mostly used PSFB topologies in different applications PSFB with Full-wave Rectifier The circuit diagram is shown below It is combination of full-bridge inverter (DC-AC), high-frequency transformer, and full-wave rectifier (AC-DC) with diodes. PSFB with Full-bridge Rectifier The circuit diagram is shown below It is combination of full-bridge inverter (DC-AC), high-frequency transformer, and…
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Why power factor correction (PFC)? and How it works for power supply and electrical system?
The power factor correction circuit is required to improve the power factor by drawing the sinusoidal current which is in-phase with the supply voltage. Ideally power factor 1 is good for the system. Mostly diode bridge rectifier is used for AC to DC power conversion due to uncontrolled and cost effective. But due to uncontrolled…
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What is Power Factor (pf)? How high value of pf is benficial in EV charging System?
Power factor correction (PFC) means improving It is defined as how much active power is drawn from grid in the amount of total power. In simple terms, Total Power (S) = Active power (P) + Reactive power (Q) Total power (S) –> Apparent power = VrmsIrms Active (Real) power (P) –> Useful power = VrmsIrms*cos(Φ)…
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Electric Vehicle (EV) Charger – Power Factor Correction (PFC) Topologies for AC-DC Converter Stage
There are many topologies which can be used for power factor improvement in the AC-DC converter stage of electric vehicle chargers Diode Rectifier + Boost PFC Converter: This is the basic PFC converter which is combination of diode bridge rectifier and boost converter. Simple structure and simple control due to single switch in boost converter.…
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Electric Vehicle (EV) – Resonant Power Converter Topologies for DC-DC power converter stage
DC-DC converter is an important stage of any EV charger. Resonant converters are most preferred DC-DC converter in EV chargers segment because of in-built features like below other than the isolation The block diagrammatic representation of any resonant power converter is shown below. It consist of The most common resonant converter topologies have been using…
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Electric Vehicle (EV) Charger – Power Module stages (AC-DC stage and DC-DC stage) and Benficial Power Converter Topologies
EV charger (either it is on-board or off-board) mainly consist of two power modules as shown below Any electrical system/module primary requires, Grid is an AC source, battery is a DC source. To charge the battery AC should be converter into DC for that purpose, AC – DC converter is must. The rectified voltage can…
