Battery impedance measurement using sinusoidal ripple current emulator
- Authors: Hossain, Kamal , Islam, Syed , Park, Sung-Yeul
- Date: 2017
- Type: Text , Conference proceedings , Conference paper
- Relation: 9th Annual IEEE Energy Conversion Congress and Exposition, ECCE 2017; Cincinnati, United States; 1st-5th October 2017 Vol. 2017, p. 2754-2759
- Full Text: false
- Reviewed:
- Description: This paper presents a sinusoidal ripple current (SRC) emulator which superimposes an ac ripple current frequency into a dc charging current in order to produce a sinusoidal ripple current without a ripple current controller. It can be used for several purposes:1) to analyze the impact of ac ripple current magnitude and frequency on the battery internal characteristics; 2) to determine the parameters related to thermal rise and lithium plating; 3) to obtain more updated parameter information for improved utilization of a battery; 4) to determine the optimal ripple current frequency at the minimum impedance point by sweeping the ripple current frequency; 5) to utilize the obtained impedance data for estimating the battery circuit parameters and SOC level. The internal characteristics of batteries are complex and dynamic; therefore, it is beneficial to use the SRC emulator to validate SRC performance in a battery stack before integrating a SRC algorithm into a battery charger. This paper describes the development procedure of a SRC emulator to produce the electrochemical impedance spectroscopy (EIS) measurement for measuring the battery internal impedance. In order to validate the performance of the SRC emulator, a 12.8 V, 40 Ah Li-ion battery was charged at C/8 rate in CC mode with ± 1 App ac ripple current perturbation with an impedance from 20 Hz to 2 kHz.
Reactive power distribution strategy using power factor correction converters for smart home application
- Authors: Islam, Syed , Maxwell, Shawn , Hossain, Kamal , Park, Sung-Yeul , Park, Sungmin
- Date: 2016
- Type: Text , Conference proceedings , Conference paper
- Relation: 2016 IEEE Energy Conversion Congress and Exposition, ECCE 2016; Milwaukee, United States; 18th-22nd September 2016 p. 1-6
- Full Text: false
- Reviewed:
- Description: Multiple unit of PFC converters can be utilized for better power quality in the residential applications. It is important to set proper amount of reactive power contribution from each unit of PFC converter to reduce power loss and increase stability. To set the referenced amount of reactive power contribution for each PFC converter, a dynamic supervisory controller is necessary. In this paper, a wireless based supervisory controller is introduced to mitigate the problem. Multiple unit of unidirectional bridgeless ac-dc boost PFC converters were used as reactive power resources in a smart home application. The supervisory controller is comprised of a discrete Proportional-Integral controller and distributor which sets the reactive power references for each PFC converter. The controller was designed based on the systems identification method. The controller was designed and simulated considering different communication delays. In the ideal condition, the system had no communication delay. However, actual practical system had some reasonable delay. The effect of the use of supervisory controller was observed for dynamic load changing conditions. The simulation was done by using SIMULINK. Reactive power consumption from grid becomes 0VAR within 0.25 second for ideal condition. However, for the actual condition this become 9.35 seconds.
Capability, compatibility, and usability evaluation of hardware-in-the-loop platforms for DC-DC converter
- Authors: Maxwell, Shawn , Islam, Syed , Hossain, Kamal , Park, Sung-Yeul
- Date: 2016
- Type: Text , Conference proceedings , Conference paper
- Relation: 2016 IEEE Energy Conversion Congress and Exposition, ECCE 2016; Milwaukee, United States; 18th-22nd September 2016 p. 1-6
- Full Text: false
- Reviewed:
- Description: This paper evaluates the capability, compatibility, and usability of Hardware-in-the-Loop platforms for DC-DC converter. This was accomplished by interfacing the platforms with a physical power stage as well as a controller. The employed platforms are Hi-Rel Power-pole board, Texas Instruments Digital Controller, RTDS, OPAL-RT, dSPACE, and Typhoon. Two sets of experimentation were performed: the power stage represented by the Power-pole board, RTDS, OPAL-RT, dSPACE, and Typhoon and the controller replaced by TI DSC, RTDS, OPAL-RT, dSPACE, and Typhoon. Three points of evaluation for a testing platform that are of interest to industrial researchers as well as academia are capability (speed or modeling capacity), compatibility (ease of porting models from other platforms), and usability (ease of use of software and hardware). This paper provides an introductory resource for research and education by providing results of a simple buck converter example.
Performance analysis of filter sensing board for measuring the battery online impedance
- Authors: Hossain, Kamal , Islam, Syed , Park, Sung-Yeul
- Date: 2016
- Type: Text , Conference proceedings , Conference paper
- Relation: 2016 Asian Conference on Energy, Power and Transportation Electrification, ACEPT 2016; Singapore, Singapore; 25th-27th October 2016 Vol. 2017, p. 1-6
- Full Text: false
- Reviewed:
- Description: This paper presents the performance analysis of filter sensing board for extracting ac ripple information to estimate the battery impedance for the sinusoidal ripple current charging technique. The charging ac ripple content is extracted from the battery voltage and current by filtering the dc component using an op-amp filter circuit while producing a 90° phase angle in order to transform the a-p frame for calculating the battery impedance. The digital signal processor based board has computational burden due to the many transformations and calculation steps with limited ADC sensing range between 0 to 3 V at 12 bit resolution. Additionally, in the software approach it is observed that the gain and phase angle of sensor output is changing with respect to the AC input ripple frequency. In this paper, we propose a filter sensing circuit board to reduce the transformation and computation burdens for measuring the AC impedance. In this proposed method, the impedance is calculated via a dSPACE interface with a ± 10 V ADC sensing range at 16 bit resolution. This paper also verifies the variation of phase delay between the sensor input and output at different frequencies by using the proposed 16-channel analog filter circuit. A prototype ac load is used as an experimental test bed considering the equivalent battery internal impedance model for measuring the accuracy of the filter sensing board. Finally, the performance of this proposed approach is verified by comparing the experimental result with the simulation and the commercial frequency response analyzer results.