Particle swarm optimization for design of class-E amplifier

Abstract

The class-E amplifier is one of the switching amplifiers, which satisfies the class-E switching conditions. It is, however, difficult to determine the values of the passive elements included in the circuit for achieving the class-E switching conditions. The particle swarm optimization algorithm for designing the class-E amplifier is presented in this paper. To reduce the computational cost and consider the nonlinear effects of MOSFET in the amplifier, a circuit simulator which finds the steady-state solution is introduced. Moreover, OpenMP, which is an API for multi-platform shared-memory parallel programming, is used in the developed program to accelerate the proposed procedure. In a design example, the class-E amplifier, the element values of which were obtained by the particle swarm optimization, showed a good performance.

An automated design procedure for class-E amplifier

“…Then, the optimization to find the passive element values using SPICE is a black-box optimization, but it suffers from its heavy computational cost. Even though circuit simulators, which have a tool that steady-state waveforms can be obtained efficiently, are used, the computation is still costly for the optimization [11]. Therefore, the MOSFET in the circuit of Fig.…”

“…For 32 trials, PSO found the same point that satisfies both the ZVS and ZDS conditions; thus, this point is considered to be an intersection point of two curves that respectively satisfy the ZVS and ZDS conditions. Extending the searching area as A, B ∈ [0.01, 30.0], PSO was again applied, in which 2000 trials were run with each (9) and (10) and 100 trials were with (11). Figure 3(b) shows the global minimum points found by PSO, in which the ZVS and/or ZDS conditions are fulfilled at many points.…”

“…Even if the design is slightly changed, the analytical expression must be reproduced; thus, this procedure using the Newton-Raphson method is not fully automated. Alternatively, a black-box optimization procedure is presented in [11], in which the ZVS and ZDS conditions are calculated by a commercial circuit simulator. Then, particle swarm optimization (PSO), which is a metaheuristic algorithm [10], is applied to find the solution.…”

High-frequency resonant gate driver with isolated class-E amplifier

“…The class-E amplifier [17][18][19][20][21][22][23][24][25][26][27] is a typical high-frequency resonant circuit. Because the switch voltage can satisfy the class-E zero-voltage switching and zero-derivative switching (ZVS/ZDS) conditions in the class-E amplifier, it is possible to achieve low switching losses at high frequencies.…”

Behavioral modeling of Class-E switching circuits via Weierstrass canonical form

“…However, simulations need to be run repeatedly to know the performances such as power conversion efficiency, ripple, and ZVS or ZDS condition depending on the design parameters. Moreover, direct use of such simulators is not suitable for design schemes based on an optimization algorithm [8,9,16]. Therefore, an effective model that simulates the steady state behavior of Class-E amplifier is required.…”