Abstract
The second-order ripple power of single-phase converter causes second-order ripple voltages on the DC bus. For eliminating second-order ripple components, passive power decoupling methods including DC bus electrolytic capacitors have some shortcomings, such as low power density and poor stability of converters. Thus, an active power decoupling method based on a single-phase converter is proposed in this paper. The control method, taking single-phase voltage source pulse width modulation (PWM) rectifier (single-phase VSR) as the basic converter and adopting a buck-boost power decoupling circuit, introduces second-order ripple of DC bus voltage into a power decoupling circuit. The ripple acts as compensation of the phase deviation between the command value and the actual value of the second-order ripple current. Therefore, estimation of the second-order ripple current is more accurate, the power decoupling circuit absorbs the second-order ripple power behind the H-bridge more completely, and the DC bus voltage ripple is effectively suppressed accordingly. Finally, experimental results of the single-phase VSR are given to verify the validity of the proposed method.
Highlights
Single-phase voltage source pulse width modulation (PWM) converters are widely used in uninterruptible power supply, locomotive traction, DC microgrids, and renewable energy systems because of its high efficiency and reliability [1,2,3,4,5]
The second-order ripple component of the bus voltage was introduced in the control, power decoupling control strategy with second-order ripple current estimation was proposed in this phasecomponent deviation between the command value and the actual value the paper.which
The power decoupling circuit can effectively absorb the second-order which compensated the phase deviation between the command value and the actual value of the ripple power, and the DC bus voltage ripple is controlled within the allowable range
Summary
Single-phase voltage source pulse width modulation (PWM) converters are widely used in uninterruptible power supply, locomotive traction, DC microgrids, and renewable energy systems because of its high efficiency and reliability [1,2,3,4,5]. By controlling the on/off states of switches, the conversion between the second-order ripple energy of the DC bus and the energy of storage element in the power decoupling circuit is realized This method greatly reduces system volume and prolongs the service life of the system. In order to obtain second-order ripple currents accurately, the pulsating current after flowing through the H-bridge is directly sampled by the authors in [33] As a result, this method places high demands on the switching frequency and accuracy of sampling. Considering the complexity of DPDC and the imprecision of estimation, a control strategy based on an IPDC buck-boost-type power decoupling circuit is proposed in this paper. The second-order ripple of DC bus voltage is introduced to control the decoupling inductor current The advantage of this control method is that the phase deviations of H-bridge voltage and AC current are considered. The correctness of the control method is verified by simulation and experimentation
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call