Voltage Double Closed-loop Control Research Articles

Synchronous Generator Rectification System Based on Double Closed-Loop Control of Backstepping and Sliding Mode Variable Structure

Low-voltage and high-current direct current (DC) power supplies are essential for aerospace and shipping. However, its robustness and dynamic response need to be optimized further on some special occasions. In this paper, a novel rectification system platform is built with the low-voltage and high-current permanent magnet synchronous generator (PMSG), in which the DC voltage double closed-loop control system is constructed with the backstepping control method and the sliding mode variable structure (SMVS). In the active component control structure of this system, reasonable virtual control variables are set to obtain the overall structural control variable which satisfied the stability requirements of Lyapunov stability theory. Thus, the fast-tracking and the global adjustment of the system are realized and the robustness is improved. Since the reactive component control structure is simple and no subsystem has to be constructed, the SMVS is used to stabilize the system power factor. By building a simulation model and experimental platform of the 5 V/300 A rectification module based on the PMSG, it is verified that the power factor of the system can reach about 98.5%. When the load mutation occurs, the DC output achieves stability again within 0.02 s, and the system fluctuation rate does not exceed 2%.

Simulation Study of Three - phase PWM Rectifier with Square of the Voltage Double Closed Loop Control

Based on the rotating coordinate system model, the mathematic analysis of the three-phase voltage-sourced PWM rectifier is carried out, and its feed-forward decoupling control strategy is studied. In order to realize the fast response of DC voltage and improve the dynamic and static performance of the rectifier, the double-closed-loop control of outer square of voltage loop and inner current loop is established. The control system of three-phase voltage-sourced PWM rectifier based on space vector modulation algorithm is designed. The simulation results demonstrate the designed model is accurate, and can achieve unity power factor control, DC voltage fast responses, and has not steady-state error.

Design of constant current source to drive analog coil of space magnetic environment

To reach the requirements that the space environment simulation coil 's magnetic induction intensity can continuously adjust from 0 to 20 Gs,and the magnetic field stability can be better than 1%,main circuit topology structure using a voltage source in series with a current source,combined with the voltage double closed loop control and the current closed loop negative feedback control methods,achieved a stable current output,reduced the power consumption of the metal-oxide-semiconductor field-effect transistor( MOSFET),and improved the efficiency of the constant current source. The test results show that the constant current source output current ranges from 0 to 10 A,Helmholtz coil's center magnetic induction intensity can reach the design requirements of 20 Gs,the current stability is better than 0. 1%,and the magnetic field stability is better than 1%.