scholarly journals A Novel Control Strategy for DC-Link Voltage Balance and Reactive Power Equilibrium of a Single-Phase Cascaded H-Bridge Rectifier

Energies ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 51 ◽  
Author(s):  
Chengwei Luo ◽  
Derong Luo ◽  
Shoudao Huang ◽  
Gongping Wu ◽  
Hongzhang Zhu ◽  
...  
Keyword(s):  
Working Conditions ◽  
Duty Cycle ◽  
Control Strategy ◽  
Reactive Power ◽  
Coupling Effect ◽  
Active Duty ◽  
Integral Control ◽  
Loop Control ◽  
Voltage Balance ◽  
Bridge Rectifier

The dc-link voltage balance and reactive power equilibrium of the cascaded H-bridge rectifier (CHBR) are the prerequisites for the safe and stable operation of the system. However, the conventional PI (Proportional-Integral) control strategy only puts emphasis on the CHBR dc-link voltage balance without taking into account its reactive power equilibrium under capacitive and inductive working conditions. For this reason, this paper has proposed a novel control strategy for the CHBR that can not only balance dc-link voltage, but also achieve reactive power equilibrium and eliminate the coupling effect between the voltage-balancing controller (VBC) and original system controller (OSC). The control strategy can achieve dc-link voltage balance and the reactive power equilibrium of the CHBR through modifying the active duty cycle by closed loop control, and adjusting the reactive duty cycle relatively according to the modifiable amount of the active duty cycle. Moreover, the strategy can eliminate the coupling effect between the VBC and OSC by the open loop control modification of the active and reactive duty cycle of any H-bridge module in CHBR. Simulations and experiments have shown that the proposed control strategy is feasible and effective in performing the CHBR dc-link voltage balance and reactive power equilibrium under all working conditions and load variations.

A Novel Control Strategy for Three-Phase Four-Wire STATCOM

2012 ◽  
Vol 516-517 ◽  
pp. 1722-1727 ◽  
Author(s):  
Wei Jun Yun ◽  
Gang Yao ◽  
Li Dan Zhou ◽  
Chen Chen ◽  
Jun Min Pan
Keyword(s):  
Control Strategy ◽  
Power Distribution ◽  
Distribution System ◽  
Reactive Power ◽  
Control Method ◽  
Loop Control ◽  
Power Distribution System ◽  
Imbalance Problem ◽  
Three Phase ◽  
Close Loop Control

Nowadays Static Synchronous Compensator (STATCOM) has gradually become one of the representative techniques in the field of dynamic reactive power compensation in the power distribution system. This paper analyzed the topology and the voltage imbalance problem of the up and down capacitors on DC side of the three-phase four-wire STATCOM. In allusion to the imbalance problem of neutral point, a novel control strategy based on the control of zero-sequence current was proposed. By the triple close-loop control strategy, the STATCOM can achieve great control accuracy and dynamic performance. Simulation result proves that the proposed control method is effective.

scholarly journals An Input-Parallel-Output-Series Switched-Capacitor Three-level Boost Converter with a Three-Loop Control Strategy

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2631
Author(s):  
Jianfei Chen ◽  
Caisheng Wang ◽  
Jian Li
Keyword(s):  
Control Strategy ◽  
Current Loop ◽  
Loop Control ◽  
Dc Microgrids ◽  
Solar Power Generation ◽  
Capacitor Voltage ◽  
Industry Applications ◽  
Voltage Balance ◽  
Simulation And Experiment ◽  
Parallel Output

There has been increasing interest for industry applications, such as solar power generation, fuel cell systems, and dc microgrids, in step-up dc-dc converters with reduced number of components, low component stress, small input ripples and high step-up ratios. In this paper, an input-parallel-output-series three-level boost (IPOS-SC-TLB) converter is proposed. In addition to achieving the required performance, the input and output terminals can share the same ground and an automatic current balance function is also achieved in the IPOS-SC-TLB converter. Besides, a capacitor voltage imbalance mechanism was revealed and a three-loop control strategy composed of output voltage loop, input current loop and voltage-balance loop was proposed to address the voltage imbalance issue. Finally both simulation and experiment studies have been conducted to verify the effectiveness of the IPOS-SC-TLB converter and the three-loop control strategy.

scholarly journals The Reactive Power Support Strategy based on Dual-loop Control for Three-phase Grid-connected Inverter

2020 ◽  
Vol 182 ◽  
pp. 02011
Author(s):  
WAN Qian ◽  
Xia Chengjun ◽  
Azeddine Houari ◽  
Zhao Xue ◽  
Xia Chengjun ◽  
...  
Keyword(s):  
Control Strategy ◽  
Reactive Power ◽  
Low Voltage ◽  
Renewable Energy Sources ◽  
Active Power ◽  
Electric Power System ◽  
Pv System ◽  
Loop Control ◽  
Pv Array ◽  
Three Phase

Renewable energy sources (RESs) generally connected with electric power system via power electronic interface. This paper presents a reactive power and voltage (Q/V) control strategy of three-phase photovoltaic (PV) system to offering reactive power based on the typical dual-loop control topology. It is worth mentioning that control strategy can support reactive power when a low voltage fault occurs in AC bus without additional compensation device. With the help of the decoupling control, the PV array can generate active power as much as possible in variable external solar radiation conditions. The voltage of PV arrays is adopted as the objective, which on account of the easy availability and controllability of voltage, to control output active power. Besides, accurately modeling process from a PV cell to PV array is described in the beginning to acquire the P-V and V-I characteristics of PV arrays, which promote the designment of Q/V control.

Control Strategy of Vehicle Suspension Damping System Based on MATLAB

2012 ◽  
Vol 253-255 ◽  
pp. 2117-2120
Author(s):  
Yu Zhuo Men ◽  
Hai Bo Yu ◽  
Xian Sheng Li ◽  
Yue Wei Li
Keyword(s):  
Working Conditions ◽  
Control Strategy ◽  
Closed Loop ◽  
Vehicle Suspension ◽  
Closed Loop Control ◽  
Lateral Deviation ◽  
Lane Changing ◽  
Loop Control ◽  
Yaw Stability ◽  
The Impact

In order to study the impact of the suspension damping system on the vehicle riding stability, the PID controlling means for suspension damped neural network is presented, implementing a closed-loop control of yaw stability for vehicles. For the two typical working conditions of single lane changing and step steering, the MATLAB software is used for simulation. The result shows that controlling over the vehicle’s lateral deviation movement through suspension damper, it can reduce significantly the load transfers of both the left wheels and right wheels, so that to effectively restrain a vehicle’s over-steering.

Study on Improvement Transient Stability of the Large-Scale Wind Farms Integration with STATCOM

2013 ◽  
Vol 385-386 ◽  
pp. 1082-1085 ◽  
Author(s):  
Yan Juan Wu ◽  
Lin Chuan Li ◽  
Fang Zhang
Keyword(s):  
Power System ◽  
Control Strategy ◽  
Large Scale ◽  
Transient Stability ◽  
Reactive Power ◽  
Wind Farms ◽  
Double Loop ◽  
Loop Control ◽  
Simulation Results

In view of a serious threat for the transient stability of the power system being caused by the large-scale wind farms integration, and combining with advantages of STATCOM which can quickly restore the fault voltage and fastly, flexibly and smoothly compensate the reactive power, a method is proposed using STATCOM controller of to improve transient stability of the power system integrated by large-scale wind farms. The control strategy of the STATCOM controller uses adaptive double loop control. The role of the device to improvement transient stability of the power system is studied under the condition of serious fault. by simulation comparison with the condition without STATCOM controller installed at the same place. The simulation results show that the STATCOM controller can clearly improve transient stability of the power system integrated by large-scale wind farms.

Research on Control Strategy for the Three-Phase Grid-Connected Inverter

2012 ◽  
Vol 614-615 ◽  
pp. 1578-1582
Author(s):  
Chun Qing Qi ◽  
Yi Ruan ◽  
Feng Wen Cao
Keyword(s):  
Control Strategy ◽  
Reactive Power ◽  
Response Speed ◽  
Current Control ◽  
Loop Control ◽  
Closed Loop Control System ◽  
Three Phase ◽  
Control Scheme ◽  
Loop Control System ◽  
Grid Connected Inverter

This paper proposes a control strategy，based on the grid voltage oriented vector control (VOC), which makes three-phase inverter control the active and reactive power of grid-connected inverter under the premise of the direct current control. This paper analyzes the principle of three phase photovoltaic grid connected inverter and describes the control structure of the inverter. The control strategy can overcome the deficiencies of the indirect current control scheme. This paper designs the current closed-loop control system, which not only improve the system dynamic response speed and output current waveform quality, while also reduce its sensitivity to parameter changes to improve the robustness of the system. The simulation results show the validity of control strategy proposed.

scholarly journals Time-Sharing Control Strategy for Multiple-Receiver Wireless Power Transfer Systems

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 599 ◽  
Author(s):  
Weikun Cai ◽  
Dianguang Ma ◽  
Xiaoyang Lai ◽  
Khurram Hashmi ◽  
Houjun Tang ◽  
...  
Keyword(s):  
Control Strategy ◽  
Output Voltage ◽  
High Efficiency ◽  
Coupling Effect ◽  
Cross Coupling ◽  
Time Sharing ◽  
Voltage Control Strategy ◽  
Bridge Rectifier ◽  
The Cross ◽  
Target Output

The cross-coupling effect between the induction coils of a multiple-receiver wireless power transfer (MRWPT) system severely weakens its overall performance. In this paper, a time-sharing control strategy for MRWPT systems is proposed to reduce the cross-coupling between receiver coils. An active-bridge rectifier is introduced to the receivers to replace the uncontrollable rectifier to achieve synchronization of the time-sharing control. The synchronization signal generated by an active-bridge rectifier can be directly used to realize the synchronization of time-sharing control and hence saved the traditional zero-crossing point detection circuits for time-sharing circuits. Moreover, the proposed time-sharing system has the advantages of both operating under a resistance-matching condition and providing target output voltage for each receiver. Furthermore, a voltage control strategy was developed to provide both high efficiency and a target output voltage for each receiver. Finally, the simulation and experimental results show that the time-sharing MRWPT system reduced the cross-coupling effect between the receiver coils, and the voltage control strategy provided both a high efficiency and a target output voltage for each receiver.

scholarly journals A Novel Control Strategy for the Frequency and Voltage Regulation of Distribution Grids Using Electric Vehicle Batteries

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1435
Author(s):  
Mohammadshayan Latifi ◽  
Reza Sabzehgar ◽  
Poria Fajri ◽  
Mohammad Rasouli
Keyword(s):  
Control Strategy ◽  
Pulse Width Modulation ◽  
Reactive Power ◽  
Experimental Studies ◽  
Voltage Regulation ◽  
Phase Detector ◽  
Double Loop ◽  
Loop Control ◽  
Active And Reactive Power ◽  
Local Grid

In this study, a double-loop control strategy is proposed for power grid frequency and voltage regulation using plug-in electric vehicles (PEVs) connected to the grid through a three-level capacitor clamped inverter. The frequency and voltage regulation problem is first formulated using vector space analysis and phasor diagrams to find the boundaries and constraints in terms of the system parameters. The derived formulas are then utilized to design a double-loop controller using an exclusive phase detector control loop and a novel pulse width modulation (PWM) scheme to effectively regulate the frequency and voltage of the grid. The effectiveness and feasibility of the proposed control strategy are evaluated through simulation and experimental studies. This approach can benefit both the customers and the grid operator, as it facilitates utilizing the batteries of the connected PEVs to supply a portion or all of the active and reactive power demand, hence regulating the frequency and voltage of the grid. The extent to which active and reactive power can be supplied depends on the number of PEVs connected to the local grid.

scholarly journals Harmonic Mitigation of PV Based Grid-Connected Hybrid System using ANFIS

2019 ◽  
Vol 9 (1) ◽  
pp. 2855-2860
Keyword(s):  
Hybrid System ◽  
Control Strategy ◽  
Closed Loop ◽  
Reactive Power ◽  
Pi Controller ◽  
Active Power ◽  
Closed Loop Control ◽  
Source Condition ◽  
Loop Control ◽  
Composite Control

Deriving quality power is the vital problem in power system network. The main focus of the paper is to reduce the power quality issues mainly the reduction of harmonics using source compensation technique. This paper proposes a grid integrated hybrid system with ANFIS. This hybrid system mainly consists of PV panel, inverters, fuel cell, batteries and filters. Based on working principle and characteristics of the proposed hybrid system, the composite control strategy about active power, reactive power and harmonic suppression is proposed. The composite control strategy are of two loops ie., a single closed-loop control response active power and reactive power, double closed-loop control responses harmonics. Both balanced source condition and unbalanced source condition for three phase system are developed by Simulink model. The balanced and unbalanced source performance is done by using ANFIS. PI controller and ANFIS are compared with their Simulink results. Simulation results shows the performance of ANFIS is better than PI controller.

Sign in / Sign up

Export Citation Format

Share Document