tailieunhanh - Electrical Generation and Distribution Systems and Power Quality Disturbances Part 15

Tham khảo tài liệu 'electrical generation and distribution systems and power quality disturbances part 15', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Some Basic Issues and Applications of Switch-Mode Rectifiers on Motor Drives and Electric Vehicle Chargers 267 Bridgeless boost SMR System configuration Fig. 10 shows the bridgeless boost SMR its control scheme is identical to those shown in Fig. 6 with the two switches being respectively operated in positive and negative half cycles. Although the efficiency of bridgeless SMR can be slightly increased it possesses the common mode EMI problem due to the large parasitic capacitance between the output and ground which provides a relatively low impedance path. To reduce this problem the boosting inductor is divided into two equal inductors and they are placed at AC source side. Circuit design The specifications are identical to those listed above. The two inductors L1 and L2 in Sec. are used here as the two bridgeless boost SMR inductors . L1 L2 . Fig. 10. Schematic and control scheme of the developed bridgeless boost SMR Control schemes Current controller Following the similar process introduced in Sec. one can get KP Kpi . Hence KPi is set and the integral gain is chosen via trial-and-error. Finally K 2000 Gci s K 3 20 Voltage controller The PI voltage feedback controller is chosen to be K 200 Gcv s Kpv ỵ 8 20 21 Experimental results The measured key waveforms are almost identical to Fig. 9 and are not repeated here. Table 2 lists the measured efficiencies n THDi of iac and PF at two loads. From Tables 1 and 2 one can find the slight higher efficiencies being yielded by the bridgeless SMR. Current-Fed Push-Pull CFPP isolated boost SMR System configuration and operation The power circuit and control scheme of the CFPP isolated boost SMR are shown in Figs. 11 a and 11 b . In making the analysis some assumptions are made i all circuit 268 Electrical Generation and Distribution Systems and Power Quality Disturbances components are ideal ii the active voltage clamp circuits including S3 S4 and Ca are .