Micro/small wind turbine power control for electrolysis applications

TY - JOUR

T1 - Micro/small wind turbine power control for electrolysis applications

AU - Dixon, Christopher

AU - Reynolds, Stephen

AU - Rodley, David

N1 - Copyright: © 2015 Elsevier Ltd. All rights reserved.

PY - 2016/3

Y1 - 2016/3

N2 - This paper compares the efficiency of three power converter and maximum power point tracking (MPPT) systems for connecting a micro/small wind turbine to an electrolyser stack: a conventional DC–DC voltage converter with hill-climb search (HCS); a novel variable electrolyser cell load controller where the number of series cells varies to allow MPPT; a novel hybrid DC–DC voltage converter integrated with direct-connect circuitry, variable cell control and lookup-based MPPT. The variable cell and hybrid converters demonstrated superior performance, averaging efficiencies 2–4% higher than the conventional converter, reaching near ideal at a wind speed of 7.7 ms−1 due to direct connection. MPPT function measured electrolyser current as a power reference. HCS performed MPPT at approx. 98% of ideal but requiring very advanced function including variable step size and intelligent perturbation to achieve this during dynamic conditions. The variable cell and hybrid converters produced superior MPPT (based on lookup data) to HCS. This demonstrates alternative novel power control and MPPT approaches for low-cost and efficient hydrogen production from micro/small wind-electrolysis systems.

AB - This paper compares the efficiency of three power converter and maximum power point tracking (MPPT) systems for connecting a micro/small wind turbine to an electrolyser stack: a conventional DC–DC voltage converter with hill-climb search (HCS); a novel variable electrolyser cell load controller where the number of series cells varies to allow MPPT; a novel hybrid DC–DC voltage converter integrated with direct-connect circuitry, variable cell control and lookup-based MPPT. The variable cell and hybrid converters demonstrated superior performance, averaging efficiencies 2–4% higher than the conventional converter, reaching near ideal at a wind speed of 7.7 ms−1 due to direct connection. MPPT function measured electrolyser current as a power reference. HCS performed MPPT at approx. 98% of ideal but requiring very advanced function including variable step size and intelligent perturbation to achieve this during dynamic conditions. The variable cell and hybrid converters produced superior MPPT (based on lookup data) to HCS. This demonstrates alternative novel power control and MPPT approaches for low-cost and efficient hydrogen production from micro/small wind-electrolysis systems.

KW - Renewable hydrogen production

KW - Micro/small wind turbine

KW - Electrolysis

KW - Maximum power point tracking

KW - Hill-climb search

U2 - 10.1016/j.renene.2015.09.055

DO - 10.1016/j.renene.2015.09.055

M3 - Article

SN - 0960-1481

VL - 87

SP - 182

EP - 192

JO - Renewable Energy

JF - Renewable Energy

IS - 1

ER -