A novel pulse density modulation with semi-bridgeless active rectifier in inductive power transfer system for rail vehicle

Abstract

In this paper, a novel pulse density modulation (PDM) with semi-bridgeless active rectifier (S-BAR) in inductive power transfer (IPT) system for rail vehicle is proposed. It is to reduce switching losses of the active rectifier in pickups. In the control method, the insulated-gate bipolar transistors (IGBTs) in the S-BAR are controlled by synchronous PDM signals, so that zero-voltage switching (ZVS) and zero-current switching (ZCS) can be achieved in the whole output power range. The output power is regulated by changing the pulse density (PD) of the S-BAR since the it is almost linear proportional with the PD in high quality factor of pickup side. The communication device between the primary side and pickup side is not necessary anymore. The detailed theoretical analyses of the PDM method are provided, and its advantages are shown in a 7.5kW IPT prototype for rail vehicle. The experimental results are presented to verify the analysis and demonstrate the performance. The overall efficiency of the system by PDM control is 74.2% which is improved by 4% compared with phase shift (PS) control at light load.

Operation of Inductive Charging Systems Under Misalignment Conditions: A Review for Electric Vehicles

“…Researchers in [161] and [162] proposed an approach based on a symmetrical bridgeless active rectifier where the converter is operated using pulse density modulation (PDM). These proposals aim to achieve soft switching, which is compatible with the effects of misalignments.…”

Comparison of Control Techniques for Series Resonant Converter

“…In FM and PSM, gate signals of the power switches can be obtained with analog integrated circuits or programmable circuit elements such as microcontrollers [29][30][31]. The logic circuit or memory elements are required to obtain gate signals of the power switches in the regular or irregular PDM [18][19][20][21][22]. The logic control circuit of the regular PDM used in experimental studies is given in Figure 4a.…”

“…Amount of sub harmonics also decreases with the irregular PDM. However, this method requires complex and large logic circuits or memory elements to obtain gate signals of the power switches [19][20][21][22]. In the regular PDM, the control signals of the power switches can be obtained by simple logic circuits [23].…”

The Parametric Optimization of Voltage Multiplier

“…In comparison with other similar constructions, it is highly efficient and compact. The analysis of an active transistor rectifier for railway transport was T reviewed in [9]. In this device the three-phase voltage is rectified and then turned into alternating voltage of another frequency.…”