## 1 Introduction  
Many of the industrial applications including telecom power applications currently used active-controlled AC/DC converters to offer efficient power supplies with high-power density. Most of the active-controlled AC/DC converters are designed based on the boost converter technique, optimal design, and controlling of the operation of the boost converter at high power density offers high input power factor (PF), reducing total harmonic distortion (THD) and the circuit power losses, and increasing the conversion efficiency [1, 2]. The AC/DC power supply with two stages, as illustrated in Figure 1, is the optimal configuration to obtain high values for the input PF and power efficiency. Two-stage active AC/DC telecom power supply consists of the PFC (power factor correction ) to regulate the input power factor and the DC/DC converter stage, which is used to regulate the bus voltage of the PFC stage (320-410 V) to the telecom power applications voltage level (45-63 V) [3, 4]. The front stage of the telecom AC-DC power supply is the PFC stage which implements to deliver the power conversion with lower reactive power consumption, lower total harmonic distortion (THD), and, then, input supply power with a high-power factor (PF). According to the power applications, many types of PFC converters are widely used, such as the conventional [5, 6, 7], the interleaved [8, 9, 10, 11], and bridgeless [12, 13, 14] PFC boost converters. The conventional PFC topology as shown in Figure 1(a) is the basic topology as most the other PFC converters are derived from this topology. Moreover, for most of the power applications, this circuit topology is the most commonly used circuit because of its good performance, low cost, simple operations, and lower requirements for the power and control circuit designs, but the electromagnetic interface (EMI) level of the conventional CCM (continues-current-conduction mode ) PFC is high due to the high ripple current in the input side [1,15]. Another technique to implement the PFC converters can be classified as interleaved PFC boost converters as shown in the schematic circuit in Figure 2b. Interleaving means channeling the power flow from the input to the output into two or more channels and add them at the output point. By doing this, the problem of the input ripple current can be solved, also, as the number of interleaved channels increased, the power rating will be increased. Another advantage of this approach is better thermal performance as it uses two inductors which are approximately half the size of the conventional topology. The use of two inductors with a small current rating reduces the total size and total weight of the boost inductor, furthermore, it can increase the thermal performance of the converter. Recently, different emerging techniques to improve the performance of the interleaved PFC converters are employed such as; the modification on the interleaved PFC circuit by connecting series capacitor to reduce the switching losses, reduced the voltage stress across the semiconductors as compared with the traditional interleaved boost converter [16], also, the proposed technology to minimize the input current ripple of the interleaved PFC converter by controlling the switching driving signals and without any change in the  
Figure 1: Construction of the industrial high-power density telecom power supply. Figure 2: Schematic circuits of the different telecom PFC (power factor correction ) topologies: (**a**) conventional topology; (**b**) interleaved topology; (**c**) bridgeless topology. converter model parameter, which is presented in [17]. The digitally controlled double dual boost interleaved PFC converter with high voltage gain, small input current ripple as compared with traditional interleaved PFC converter, which is presented in [18]. The bridgeless PFC typologies as shown in Figure 2c has higher efficiency as compared with the other PFC topologies since the input bridge rectifier is not used.