A Wide Range and High Swing Charge Pump for Phase Locked Loop in Phasor Measurement Unit

Abstract

Phasor Measurement Units are widely utilized in power systems to provide synchrophasor data for a verity of applications, mainly performed by Energy Management Systems (EMS). Synchrophasors are measured at different parts of the network and transmitted to Phasor Data Concentrator (PDC) at a rate of 30-60 samples per second. The synchronization is done by means of a phase locked oscillator inside PMU which uses clock signal of the Global Positioning System (GPS). In this paper a novel charge pump with an appropriate operation capability in phaselocked-loops is presented. By using this phase locked loop in phase measurement unit, the total performance of this circuit will be improved. The proposed charge pump uses current mirror techniques in order to achieve a wide range of output voltage to control the oscillator and also has a good performance in a wide range of frequency from 33MHz to 555MHz. This circuit is designed and simulated in TSMC 0.18um CMOS technology. The proposed charge pump only consumes 390uW power in supply voltage of 1.8V at 500MHz and has a maximum current of 16.43uA with a acceptable current matching between source and sink currents. It is also capable to be used in a wide frequency range and low power applications.