• Journal of Drive and Control
• /
• v.16 no.2
• /
• pp.80-90
• /
• 2019

Fuel cell hybrid electric vehicle is an attractive solution to reduce pollutants, such as noise and carbon dioxide emission. This study presents an approach for energy management and control algorithm based on energetic macroscopic representation for a fuel cell hybrid electric vehicle that is powered by proton exchange membrane fuel cell, battery and supercapacitor. First, the detailed model of the fuel cell hybrid electric vehicle, including fuel cell, battery, supercapacitor, DC-DC converters and powertrain system, are built on the energetic macroscopic representation. Next, the power management strategy was applied to manage the energy among the three power sources. Moreover, the control scheme that was based on back-stepping sliding mode control and inversed-model control techniques were deduced. Simulation tests that used a worldwide harmonized light vehicle test procedure standard driving cycle showed the effectiveness of the proposed control method.

• KEPCO Journal on Electric Power and Energy
• /
• v.5 no.1
• /
• pp.25-32
• /
• 2019

K-BEMS System was introduced to reduce peak load and to save total energy of the 200 buildings that KEPCO headquarter and branch offices use. And K-BEMS system is composed of PV, battery, and hybrid PCS. KEPCO research institute has carried out this K-BEMS research project for 3 years since January 2016. In this paper, the results of the project are shown. 9 modes of test results of K-BEMS system and are operational problems were analyzed. And measures to cure the trouble are also suggested. Batteries are operated more than 20% of SOC, and less than 20% of SOC battery protection switches are automatically shutting down the system and the system no longer respond to EMS, ending the supply of PV, and so therefore to continue the PV power supply it was turn out to be necessary that the EMS should automatically change its policy to change PV only supply mode automatically when the Battery Switch automatically operated. To operate the system continuously and automatically, it is necessary to modify the minimum operational SOC value, and in addition to that the EMS computer must remember the last shut-down SOC and Voltage which interrupted the system and add some margin to reflect the measurement error in the system.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.31 no.6
• /
• pp.422-426
• /
• 2018

The lithium-ion battery pack of an electric vehicle (EV) deserves to be considered for an alternative use within smart-grid infrastructure. Despite the long automotive service life, EV batteries retain over 70~80% of their initial capacity. These battery packs must be managed for their reliability and safety. Therefore, a battery management system (BMS) should use specific algorithms to measure and estimate the status of the battery. Most importantly, the BMS of a grid-connected energy storage system (ESS) must ensure that the lithium-ion battery does not catch fire or explode due to an internal short from uncontrolled dendrite growth. In other words, the BMS of a lithium-ion battery pack should be capable of detecting the battery's status based on the electrochemical reaction continuously until the end of the battery's lifespan. In this paper, we propose a new protection algorithm for a dendritic lithium battery. The proposed algorithm has applied a parameter from battery pack aging results and has control power managing.

• Journal of Power Electronics
• /
• v.11 no.4
• /
• pp.408-417
• /
• 2011

The plug-in hybrid electric vehicles (PHEVs) are specialized hybrid electric vehicles that have the potential to obtain enough energy for average daily commuting from batteries. The PHEV battery would be recharged from the power grid at home or at work and would thus allow for a reduction in the overall fuel consumption. This paper proposes an integrated power electronics interface for PHEVs, which consists of a novel Eight-Switch Inverter (ESI) and an interleaved DC/DC converter, in order to reduce the cost, the mass and the size of the power electronics unit (PEU) with high performance at any operating mode. In the proposed configuration, a novel Eight-Switch Inverter (ESI) is able to function as a bidirectional single-phase AC/DC battery charger/ vehicle to grid (V2G) and to transfer electrical energy between the DC-link (connected to the battery) and the electric traction system as DC/AC inverter. In addition, a bidirectional-interleaved DC/DC converter with dual-loop controller is proposed for interfacing the ESI to a low-voltage battery pack in order to minimize the ripple of the battery current and to improve the efficiency of the DC system with lower inductor size. To validate the performance of the proposed configuration, the indirect field-oriented control (IFOC) based on particle swarm optimization (PSO) is proposed to optimize the efficiency of the AC drive system in PHEVs. The maximum efficiency of the motor is obtained by the evaluation of optimal rotor flux at any operating point, where the PSO is applied to evaluate the optimal flux. Moreover, an improved AC/DC controller based Proportional-Resonant Control (PRC) is proposed in order to reduce the THD of the input current in charger/V2G modes. The proposed configuration is analyzed and its performance is validated using simulated results obtained in MATLAB/ SIMULINK. Furthermore, it is experimentally validated with results obtained from the prototypes that have been developed and built in the laboratory based on TMS320F2808 DSP.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.11
• /
• pp.1052-1059
• /
• 2011

It is conducted that power characteristic variation simulation of electric propulsion system that uses fuel cells, solar cells and a battery as power sources. Combining each power source, 400W electric propulsion system have been modeled and verified. In result, without active control logic, it is confirmed that battery's power response is faster than other power sources at starting and transient condition, fuel cell and solar cell are a major electrical power during cruise condition. After completing flight, SOC is 24.2% at the winter solstice and is 93% at the summer solstice, It is revealed that active power control for sustaining proper SOC is necessary as a securing the system safety and effective power distribution.

• Proceedings of the KIPE Conference
• /
• 2003.07a
• /
• pp.168-172
• /
• 2003

This paper presents a non-electrical isolated Prototype of N+X redundant UPS with two-quadrant converter. Proposed topology has multi-functions of battery charge and discharge regulation, operates with a near unity input power factor, compensates unbalanced voltage on U bus capacitors, and regenerates the circulating active power among the inverters into battery or grid. And furthermore, this system adopts a novel wireless parallel operation algorithm of N+X redundant UPS system with no control interconnections. Simulation and experiment results are provided in this paper to prove the validity of proposed topology and wireless control algorithm.

• Journal of Power Electronics
• /
• v.8 no.1
• /
• pp.81-90
• /
• 2008

This paper presents an investigation of a voltage and frequency controller for an isolated asynchronous generator (IAG) driven. by a wind turbine and supplying 3-phase 4-wire loads to the isolated areas where a grid is not accessible. The control strategy is based on the indirect current control of the VSC (voltage source converter) using the frequency PI controller. The proposed controller consists of three single-phase IGBT (Insulated Gate Bipolar Junction Transistor) based VSC, which are connected to each phase of the IAG through three single phase transformers and a battery at their DC link. The controller has the capability of controlling reactive and active powers to regulate the magnitude and frequency of the generated voltage, harmonic elimination, load balancing and neutral current compensation. The proposed isolated system is modeled and simulated in MATLAB using Simulink and PSB (Power System Block-set) toolboxes to verify the performance of the controller.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.8 no.1
• /
• pp.40-47
• /
• 2003

A low-cost current-sensing scheme for the motor drives with MOSFET is described. Many motor drives usually employ the common current sensors to measure current for the purpose of control or protection. These current sensors, however, significantly burden the power circuit with the size and cost. The proposed current-sensing scheme utilizes information concerning MOSFET's On-voltage and On-resistance. An analogue circuit detecting On-voltage can overcome the above disadvantages because the circuit is small and is made at a low cost, and the fuzzy inference for On-resistance is also simply designed based on MOSFET's characteristics. The validity of this scheme will be experimentally verified by adopting the current control of a battery car.

• Journal of IKEEE
• /
• v.15 no.4
• /
• pp.287-292
• /
• 2011

The RF4Control stack is used with microcontrollers and IEEE(R) 802.15.4 transceivers. This paper explains the setup and power consumption measurements for the transceiver based remote controller and target node. It is assumed the reader of this paper has knowledge about RF4CE. The current consumption measurements are made using the ZigBee Platform included with the RF4Control stack. he current consumption measurements are presented, and battery life time is calculated for an remote controller. Note that the results presented in this paper are intended as a guideline only. A variety of factors will influence the battery life calculation and final measurements and calculations should be performed on ZigBee RF4CE Certified Platform.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.675-676
• /
• 2014

Photovoltaic (PV) systems bosed on solar energy offer an environmentally friendly source of electricity. A key feature of such PV sysem is the efficiency of conversion at which the power converter stage can extract the energy from the PV arrays and deliver to the load. The Maximum power point tracking (MPPT) of the PV output for all sunshine conditions allows reduction of the cost installation and maximizes the power output from the PV panel. The proposed algorithm is to control the width of the pulse for battery charging based on the open voltage of the PV panel. As a lab results, the proposed system was implemented functions to adapt to the changes of the PV open voltage, and improved the charging efficiency.