This paper presents a method of battery/supercapacitor emulator (BSE) rapid prototyping, based on modified off-the-shelf components. Low-cost commercial constant output voltage switching power supply, transformed into an input-voltage-controlled converter, is utilized as emulator power stage. The control over input voltage of the power supply is gained by appropriately altering the voltage feedback branch of the control circuitry. Consequently, it becomes possible to tightly regulate the input voltage of the device according to a predefined current–voltage relation and hence emulate any static and/or dynamic behavior by sensing the input current of the power supply and varying its input voltage appropriately. For battery or supercapacitor emulation, the desired charging characteristics may be either derived from manufacturer provided datasheet, obtained experimentally or estimated by solving the appropriate electrical equivalent circuit of the emulated storage device. In order to demonstrate the validity of the proposed method, a prototype was designed and built using an off-the-shelf boost dc–dc converter-based low-cost power supply. Dynamic input characteristics of the prototype were experimentally evaluated and two commercial storage devices (namely MR-2791 lithium ion battery and Maxwell BMOD0058-E016-B02 supercapacitor packs) charging sequences were emulated. The resulting I – V input relations were shown to closely resemble the charging behavior of real devices.

In this paper, design of a capacitor semiactive hybrid source for powering pulsed power loads based on dc power filter principle is presented. The system consists of an energy source connected directly to a load, supported by a bidirectional buck-boost dc-dc converter interfaced supercapacitor (SC). The converter is controlled such that the SC supplies the dynamic component of the load power, leaving the energy source to supply a near-constant power to satisfy average load demand. The control algorithm is adopted from the power filter theory, allowing to reduce the stress of an energy rich source despite operating under a high-power demanding load. Moreover, the SC-load voltage matching is not required and the control algorithm does not require load current sensing. Instead, energy source current of a much lower amplitude is necessary. The SC sizing methodology is proposed, and topology issues aiming to minimize the SC are discussed as well. Compared with a passive hybrid, the proposed system utilizes much lower capacitance at the expense of additional power electronics. Experimental results are presented to demonstrate the feasibility of the approach.

In this paper, instantaneous power and energy capabilities of supercapacitor (SC) connected to a power element are derived for an arbitrary power profile, given either in analytical or statistical distribution form. A class of applications is considered where the device is used as deeply cycled energy storage with significant capacity, absorbing/supplying the whole power flow or its significant component rather than shaving low-energy high-frequency peaks. The analytical derivation of SC behavior is based on simple RC model with parameters taken from a manufacturer datasheet. It is shown that the commonly adopted “state-of-charge” indication based on terminal voltage only is insufficient to reflect the energy balance for both charging and discharging; hence an alternative definition of “state-of-energy” is proposed for each direction of energy flow, depending on both instantaneous power and terminal voltage. A simplified quick noniterative sizing procedure is proposed at the expense of a slightly oversized SC. Comprehensive example is provided in order to reinforce the proposed method of analyzing SC performance and demonstrate sizing procedure.

Analytical description of a constant power fed supercapacitor behavior is revealed in the paper. The derivation is based on a simple RC model with parameters taken from a manufacturer datasheet. Different power and energy-related figures of merit are obtained using the derived expressions. It is shown that some of the performance figures used in datasheets are strictly theoretical and cannot be achieved in practice. The process of Ragone plot construction based on the proposed method is described as well. Moreover, it is shown that the upper limit of a supercapacitor voltage imposes certain limits on power and energy capabilities of the device. Extended simulation and experimental results are provided in order to reinforce the proposed method and justify the selected model for describing supercapacitor performance. Appropriate comparison of simulations and experiments shows that the simple first-order model may be utilized to predict supercapacitor behavior with reasonable accuracy to perform an initial design.

Analytical derivation of constant power loaded supercapacitor behavior is presented in the paper. Simple RC model based on manufacturer datasheet extracted parameters is employed. Power and energy related figures of merit are obtained from the derived expressions and compared to the datasheet provided values. It is revealed that some of the performance characteristics provided in most of the datasheets are theoretical and cannot be achieved in practice. The process of a realistic Ragone plot derivation based on the proposed method is described in the paper as well. It is shown that the lower limit of supercapacitor voltage imposes certain limits on power and energy capabilities of the device. Extended simulation and experimental results are provided in order to reinforce the proposed method and justify the selected RC model for describing the supercapacitor performance. By appropriate comparison of simulations and experiments it is proven that the selected model, while being oversimplified and low order, may be used to predict supercapacitor behavior with reasonable accuracy to perform at least an initial design. (C) 2013 Elsevier Ltd. All rights reserved.