Control for Three-Phase LCL-Filter PWM Rectifier with BESS-Oriented Application

Abstract

This paper deals with a battery energy storage system (BESS) in only one of its multiple operating modes, that is when the BESS is charging the battery bank and with the focus on the control scheme design for the BESS input stage, which is a three-phase LCL-filter PWM rectifier. The rectifier's main requirements comprise output voltage regulation, power factor control, and low input current harmonic distortion, even in the presence of input voltage variations. Typically, these objectives are modeled by using a dq model with its corresponding two-loop controller architecture, including an outer voltage loop and a current internal loop. This paper outlines an alternative approach to tackle the problem by using not only an input–output map linearization controller, with the aim of a single-loop current control, but also by avoiding the dq modeling. In this case, the voltage is indirectly controlled by computing the current references based on the converter power balance. The mathematical model of the three-phase LCL-filter PWM rectifier is defined based on the delta connection of the filter, which accomplishes the requirements of a 100 kW BESS module. Extensive simulation results are included to confirm the performance of the proposed closed-loop control in practical applications.

A current sensorless control method for multi‐level active front‐end rectifiers with LCL filter

“…In Figures 1c and 1f, the controller design is based on grid and rectifier currents, and grid and capacitor currents, respectively. On the other hand, the non‐linear control method presented in [22] requires measurements of grid currents, rectifier currents, and filter capacitor voltages. It should be noted that some of these current/voltage measurements are needed due to the active damping requirement in the three‐phase rectifiers with an LCL filter [23].…”

“…The resonance damping can be accomplished in two methods. The first method is known as passive damping which is realized by connecting a small resistor in the LCL filter [22]. Even though the desired damping can be obtained, this method is not preferred since it increases the losses.…”

Holistic Control Approach for the Grid-Connected Converter of a Battery Energy Storage System

“…Hence, to calculate the current reference the power balance between the AC and DC side should be maintained. In reference [26] is obtained the current peak value to guarantee the power balance for a three-phase PWM rectifier, this method permits to maintain a regulated V DC avoiding the use of a second control loop for the capacitor voltage. By using the same procedure, the three-phase references are:…”

“…Additionally, findings do not reveal the performance of a hybrid control or a unified control when the BESS is operating as a battery charger what implies that the grid-connected converter works as a PWM rectifier. PWM rectifier boosts the grid voltage towards a DC bus capacitor and the analysis considers a nonlinear mathematical model, and the order of system state increases [26], [27]. Furthermore, the controllers are different to those used for delivering energy from the battery to the grid, adding an additional control stage [8], [28].…”

Control of linear generator based on hysteresis‐SVPWM current rectification and bidirectional buck/boost converter used for energy storage

“…Nevertheless, to obtain the electrical angle in real-time for coordinate transformation, there are higher requirements for the controller's computing speed [14,15]. If the current inner loop is controlled by proportional-integral (PI), the current decoupling control in the synchronous rotating coordinate system has been unable to achieve static-free control [16,17]. For the operation of the Stirling generator system at a higher frequency, its fast forward and reverse commutation makes the phase sequence of the three-phase voltage changes once in each reciprocating cycle.…”