Direct Power Control of a Pulse Width Modulation Rectifier Using Space Vector Modulation Under Unbalanced Grid Voltages

Abstract

Compared with conventional table-based direct power control (DPC), DPC using space vector modulation (DPC-SVM) exhibits several specific features, such as a constant switching frequency and small ripples in both active power and reactive power. However, conventional DPC-SVM exhibits highly distorted grid currents when the grid voltage is unbalanced. In this study, we propose a novel and simple DPC-SVM that is effective under both ideal and unbalanced grid voltage conditions by using an extension of original instantaneous power theory. After deducing the power slopes of both active power and reactive power, the suitable converter voltage reference to nullify the errors of active power and reactive power is analytically derived, which is subsequently synthesized by SVM. The proposed DPC-SVM does not require the extraction of complex positive/negative sequence from the grid voltage/current or power compensation. Compared to prior DPC-SVM using original imaginary power, the proposed method exhibits much better performance by obtaining highly sinusoidal line currents and eliminating twice grid-frequency ripples in both active power and the reactive power under unbalanced conditions. Simulations and experimental results supported the theoretical study and confirmed the effectiveness of the proposed method.

Dynamic and static performance optimization of dual active bridge DC-DC converters

“…3 Hybrid scheme of EPS control and DPC scheme DPC scheme is one of the classical control strategies to improve dynamic performances of power converters [22,23]. Since the desired output voltage is always related to the transmission power in voltage-source converters, the transmission power is an important parameter for power converters.…”

“…Direct power control (DPC) scheme is a popular active solution to enhance dynamic performance of AC-DC or DC-AC converters [22,23]. It is well known for its strong abilities to improve dynamic and static performances of power converters.…”

Virtual-Flux-Based Predictive Direct Power Control of Three-Phase PWM Rectifiers With Fast Dynamic Response

“…In addition, uL can be obtained from (1) and (3). Then, in the virtual-flux and power estimation block, P, Q, and λL are estimated using (4), (5), and (25). The process of calculating the λL is clearly presented in Fig.…”

Direct power control of voltage source inverter in a virtual synchronous reference frame during frequency variation and network unbalance

“…4, the active and reactive powers can be represented by (19) where G PI (s) and G ROVI (s) are the transfer functions of the PI controller and the ROVI, respectively. It can be seen that P g and Q g are determined by three main parts: the active and reactive power references P gRef and Q gRef , the selected control target R com , that is, (14) and (15), and the voltage disturbance U + gdq . Since the average active and reactive powers can remain well tracked to their respective references, the average components can be removed from (19), similar to that in [22].…”