Analysis And Simulation Of Harmonics In Power System Of 1500-meter Drilling

Nowadays,a large number of frequency conversion devices are used in drilling vessel electric propulsion system,which deteriorates the environment of the drilling vessel.Drilling vessel power system in the invert capacity level changes,causing the inverter into the main source of harmonic wave in the drilling vessel.In order to suppress the harmonics generated by the drilling vessel and the load jump,this paper takes 1500 meters of working depth drilling rig as the research object,relying on the National Development and Reform Commission "1500 m operation depth drilling platform platform power station system integration" industrial project,Issues are discussed and studied,the main research is as follows:1.In order to understand the characteristics of the harmonic wave of the drilling vessel,the model of the ship is simulated by EDSAand the harmonic source of the drilling vessel is analyzed for the navigation and operation.The drilling vessel bus Voltage distortion rate and current distortion rateand select the parallel active filter to suppress the harmonics.In order to make the parallel active filter better compensate the harmonics of the drilling vessel,the detection theory and improvement algorithm of the parallel active filter harmonics,the current loop control and the improvement mode and the voltage loop control are studied respectively.2.In order to improve the accuracy of harmonic detection,the pq harmonic detection,ip-iq harmonic detection and FBD harmonic detection algorithm are analyzed theoretically.Since the three detection algorithms adopt the low-pass filter(LPF)Detection delay,affecting the detection accuracy.In this paper,an improved harmonic detection algorithm based on FBD is proposed.The algorithm uses sliding window instead of the traditional low-pass filter to detect the fundamental current and harmonic current in the power supply system of drilling vessel quickly and accurately.In the case of voltage asymmetry or voltage distortion of the drilling vessel,it can also show good results.3.To improve the accuracy of harmonic suppression,the current loop and voltage loop of the parallel power filter of drilling vessel are designed.Aiming at the current loop of the parallel active power filter,the principle of repeated shooting control and the repetitive control principle are studied respectively.Due to the poor real-time performance and low accuracy of the non-beat control current loop control,this paper combines the principle of repetitive control.The principle of the no-beat control strategy to control the current loop.Due to active power filter operation of its main circuit devices have energy loss,causing the capacitor voltage instability through the PI voltage loop Control research.the use of PI controller to solve the DC side of the capacitor voltage instability.4.The use of a designed parallel active power filter to suppress the harmonic of the drilling vessel.By comparing the current loop simulation with no-beat beat and the improved no-beat control current loop based on the repetitive control principle,the reasonableness of the improved current loop is verified.It is based on the voltage loop control simulation the PI controller,PI controller is valid.