Research On Power Supply Switching Device Based On Petrochemical Enterprises

Due to the petrochemical enterprise extranet or intranet malfunction, cases of non-normal power outage are widespread. However, the standard continuous power supply in production process is extremely high for petrochemical enterprises, malfunction will bring significant economic losses and process safety hazards to companies. When an exception of the power occurs in the petrochemical enterprise, the power switch device will require to put into standby power quickly and accurately, to ensure load run in uninterruptable power system and not affected by the impact of the larger, which can run continuously.So the power switch device is an important safeguard to ensure the enterprise continuous supply.The proportion of an induction motor is relatively large in the workloads of petrochemical enterprise. Therefore, its residual voltage characteristics have a significant impact on the power switch.This paper first analyzes the transient characteristics of induction motor running properties, loss of power and the power of heavy investment, combined with the motor torque unstable equilibrium point, the paper puts the critical switching time of power switching device, and gives analytical expressions.Secondly, doing power switch simulation based on the Simulink. simulated four different closing timing and the critical switching switching mode power switching time. And founding the shortcomings of traditional residual voltage switching and long delay switch. Meanwhile, the paper proposed critical switching time to improve the switching mode. According to the influence of the motor have different loads on the critical analysis of the switching time switching mode can be used with the corresponding load shedding protection,so improve the logic of power switching.The paper designs the power switching devices based on uC/OS-Ⅱ and ARM embedded system. It also completes the hardware and software designs in principle device analysis including modular design of hardware and multitasking design of multitasking. The System can realize the function as real-time acquisition of inlet and bus wire’s current and voltage, the logic judgment of the devices’movement, the command output of open-close, the modified logic criterion value and the slave packet response of Modbus protocol.Ultimately, after a series of simulation validation and device test, showing that this device has a certain practical value.