Research

Research interests:

Here in the RPCS laboratory, we focus on solving complex problems in mobility electrification, energy networks, energy efficiency and reduction of harmful gases. We look into these energy problems in the context of cyber-physical systems (CPS) problem. We are specifically interested in the feedback systems where we employ networked or distributed control, adaptive and predictive control, intelligent control, and real-time (time-constrained) control for power and energy management from component-level including batteries, wideband-gap power electronics to system-level including microgrids/nanogrids and buildings. In the context of the feedback system, we also employ wireless sensing using novel sensing technologies, and multi-sensory fusion algorithms to achieve reliability, flexibility and accuracy.
We provide special capability in our lab for hardware-in-the-loop (HIL) and rapid control prototyping (RCP) for testing and evaluation of the CPS in a real-time scenario. These real-time techniques can significantly reduce the cost of the system development.

Smart Battery Management Systems:
bms

Battery packs are a significant part of an electric vehicle where each individual cell within the pack shows a nonlinear behaviour due to fast charging or manufacturing defect, which results in premature ageing within the pack. Moreover, not accessing the individual cell parameters (thermal, mechanical, chemical) may result in the inaccuracy of state-of-charge (SoC) and state-of-health (SoH) estimation, and even catastrophic events like a thermal runaway.

We develop a battery management system (BMS) with multi-physics LiB models and machine-learning-based cell ageing model to accurately estimate battery degradation using specialised algorithms for SoC and SoH estimation. We also use in-cell wireless sensors to measure critical cell parameters including electrochemical, thermal and mechanical, for real-time condition monitoring and safe operation batteries. For including smart functionalities in BMS, we design a controller/observer to optimise the ageing model parameters, balance the power within the battery pack and reduce the response time in the communication of the battery pack and power electronic converter.

Funding: 

EPSRC
UKRI Global Challenge Research Fund
British Council
Innovate UK Faraday Battery Challenge

Featured projects:

Current Density Imaging in EV battery modules,
Project: Innovate UK, Faraday Challenge Feasibility Study.

Intelligent control systems for extending the life-cycle and safety of solar Li-ion battery Packs
Project: British Council Newton Fund

Extending the life-cycle of the aged Li-ion battery packs
Project: EPSRC GCRF Institutional Sponsorship

Enhancing the lifespan of Li-ion Battery Packs integrated with a novel bi-directional charger and control system
Project: EPSRC Institutional Sponsorship, EP/P511213/1

Condition Monitoring for WBG Power Electronic Converters:
 wbg_pe

Power electronics underpins modern electric and hybrid vehicles allowing efficient energy transfer between the vehicle battery system and the drive motors. EVs have to operate in a wide range of climates and geographies meaning that the electrical systems have to be designed to withstand significant overstresses, particularly from self-heating and sudden loading during normal operation. 

As a result, the power electronics are significantly over-designed to ensure sufficient reliability given the harsh operating conditions. Using wide-bandgap semiconductor materials such as silicon carbide allows significant improvements in power density and volumetric efficiency; however, posing challenges including bond-wire and die-attach degradation due to thermo-mechanical cycling, and unwanted stress on the electrical and mounting connections.
We develop prognostics for highly integrated power electronic converters for electric vehicles. The real-time prognostics, accurately estimating the state of health and the true age of the converter, will allow the vehicle management system to intelligently adjust the available power and cooling requirements. This will be achieved by dynamically adjusting the safe operating area of the power converter based on the prevailing conditions and records of the previous ageing.

Funding:

EPSRC Centre for Power Electronics
Power Electronics UK
Innovate UK

Collaborators:

Prof Martin Foster | University of Sheffield
Dr Jonathan Davidson | University of Sheffield
Dr Yihua Hu | University of Liverpool
Dr Bing Ji | University of Leicester
Dr Maher Algreer | Teesside University
Dynex Semiconductor Ltd

Distributed and networked Control of Microgrids/Nanogrids:
microgrid02

Microgrids (MGs) and nano-grids (NGs) are becoming an essential part of the clean power generation to exploit solar, wind, and wave renewable resources with energy storages to store the intermittent power and provide high-quality power for a small community. MGs can enhance the power factor (especially when grid-connected), energy security, remote energy management, and lower the maintenance. However, their control and energy management is levelised and complex and demands specific design considerations. We focus our research on developing islanded (independent) MG control and communication system, where we enhance MG modelling, stability analysis, and secondary-level control system. We use event-triggered, decentralised models for WSN-based MG with flexible architectures, reduced network traffic, and increased the sensor battery life-time.

The MG models include generators, energy storage systems, loads, power electronics converters. The models describe the MG in local control levels such as power converter, connection level such as wireless sensor network (WSN), and global control level such as MG controller. In implementing local, distributed, and hierarchical controllers, we integrate networked control strategies to provide fast communication, balance the energy level between energy storage and generation, and handle different frequency ranges, and time scales of different MG elements. To achieve MG stability in complex network scenarios like communication topology change, we develop novel controllability and observability tools. To provide the best power quality, we suppress the voltage and current harmonics and unbalanced, and reduce over- and under-voltage problems caused by increasing DGs and EVs in the MG network.

Collaborators:

Prof. Weerakorn Ongsakul | AIT, Thailand
Prof. Jing Na | KUST, Kunming, China
Prof. Saiful Huque | University of Dhaka, Bangladesh
Dr Nasif Shams | University of Dhaka, Bangladesh
SolarLand USA

Featured projects:

Microgrid distributed control
Project: EPSRC GCRF Sponsorship, EP/R512709/1

Sea Wave Energy Powered Micorgrids:
wave-energy-ecowavepower

Wave energy alone can almost provide the total planet electricity consumption ~2.11 TW and 50% of the world’s population lives within 60 km of the sea. Unlike fossil fuels, wave energy is clean, and causes no air and noise pollution, and is always available with denser energy resource compared to wind and solar. With wave energy converters (WECs), the energy contained in the sea waves is captured. However, wave energy technology is still at its infancy.

It has not been commercialized at large scale due to the unit cost caused by the maintenance, long-distance transmission and low conversion efficiency. Rather than focus on large scale wave energy farm to connect with the national grid, this project aims to develop a resilient and highly-efficient standalone microgrid (with an array of WECs) to make the wave energy economically viable with minimum maintenance and autonomous power management. To reduce the power loss and Levelised cost of energy close to solar/wind, we improve the WEC conversion efficiency using model predictive control approaches and SiC-based power electronic converters.

Collaborators: 

EcoWavePower
Dr Guang Li | Queen Mary University of London
Prof. Weerakorn Ongsakul | AIT, Thailand

Funding: 

Royal Society GCRF
Innovate UK

Advanced Electric Propulsion for Marine vessels
duodrive-propulsion

To address environmental concerns, decarbonisation is urgently needed for the transport sector including maritime transportation. Electrification of smaller marine drives is imminent (the currently used marine diesel engines are heavily polluting) and that can potentially eliminate emissions, but the powertrain needs to overcome the challenges caused by transient conditions. The smaller vessels have to increase the electric drive propulsion efficiency allowing for rapid commercialisation, improving mission endurance (battery life). Using patented direct torque & thrust measurement technique and adding predictive control/optimisation approaches to remove the transients will dramatically increase the electric drive propulsion efficiency in conventional as well as autonomous surface vessels. This also significantly improve battery life and as a result, reducing domestic emissions.

Collaborators: 

DuoDriveTrain Ltd
Associated British Ports (ABP)
Prof Xi Jiang | Queen Mary University of London

Funding: 

Innovate UK

Featured Equipment:
scalexio

SCLALEXIO – a powerful Multi-core and versatile hardware-in-the-loop (HIL) simulator that provides highly flexible channels, and a specialized I/O hardware. Control Desk Next Generation software let real-time simulation of Matlab/Simulink models, e.g. dSPACE Electrical Power Systems Simulation Package allows the real-time simulation of electrical models developed in SimPowerSystems.

microlabbox

MicroLabBox – a small all-in-one development system for rapid control prototyping (RCP). It comes with over 100 channels of different I/O types and a combination of real-time processor and FPGA functionality. Close-loop and open-loop control algorithms can be developed in Matlab/Simulink and implemented on the freely programmable FPGA of the MicroLabBox to achieve the fastest possible control sampling rate. RTI E-Motor Control block set is used in combination with FPGA programming blockset to achieve the fastest possible control sampling rate of 16MHz for motor control. 

ds1104

DS1104 R&D Controller Board – a single PCI board system for real-time control development and rapid control prototyping (RCP). Currently, two PCs in the lab have this board installed and can be used as real-time hardware for smaller control development in power electronics, electrical machines, drives, and robotics.

ds1104

LiB Temperature And Humidity Test Chamber:
Internal dimensions(mm): 400D*500W*500H
Exterior dimensions(mm) : 860D*1050W*1620H
Useful capacity: 100 Liters
Temperature range : -40°C ~ +150°C
Temperature fluctuations: ±0.5°C
Temperature uniformity: ±2.0°C
Temperature sensor: PT100 A class sensor
Humidity range: 20% ~ 98% RH, adjustable
Humidity deviation: ± 2.5%RH
Heating rate: 3°C / min
Cooling rate: 1°C / min
Heating System: Independent nichrome electronic
Cooling system: France TECUMSEH Compressors
Internal material: SUS304 stainless steel
External material: steel plate with protective coating
Power supply: AC380V 50Hz 3Phase

bts-8000

NEWARE battery testing system:
Model: BTS8000-5V50A-8CH
8 channels with individual temperature sensor
AC220V ±10% input.
Voltage: 0.5% – 100% FSR (5V to 60V)
Current: 0.5% – 100% FSR (50A)
16-bit Resolution
Data Acquisition:
Frequency: 100Hz,
Time Interval:10ms to 60000s,
Voltage Interval: 0.2% -100% FSR,
Current Interval: 0.2% -100% FSR
Response Time: ≤10ms. 1ms for current lower than 12A
Operation Mode:
Charge: Constant Current, Constant Voltage, Constant Power
Discharge: Constant Current, Constant Power, Constant Resistance Simulation: Constant Current, Constant Power
End Conditions: Voltage, Current, Step Time, Capacity, Energy and other defined variables

dc-power-supply

1500W TDK-Lambda GEN150V-10A DC power supply:
Programmable
High Power Density: 1500W in 1U
Input (85~265Vac Continuous, single phase,
47/63Hz)
Active Power Factor Correction (0.99 typical)
Output Voltage up to 600V, Current up to 200A
Built-in RS-232/RS-485 Interface Standard
Last-Setting Memory
Global Commands for Serial RS-232/RS-485 Interface
Front Panel Lock selectable from Front Panel or Software
High Resolution 16 bit ADCs & DACs
Reliable Encoders for Voltage and Current Adjustment
Constant Voltage/Constant Current auto-crossover
Independent Remote ON/OFF and Remote Enable/Disable
External Analog Programming and Monitoring (0-5V & 0-10V)
Optional Interfaces

dc-variable-load

1200W DC Electronic Load: 
EA-EL 9000 B Series, 1.2 kW,
0 VDC ~ 360 VDC
40 A
Programmable

voltage-probe

Voltage Probe
Tektronix THDP0200 Oscilloscope Probe
Probe Type: Differential
High Voltage 200MHz 1.5kV 1:50, 1:500

current-probe

Current Probe
Pico Technology TA167 200A/2000A AC/DC
BNC Connector

arduino-uno-board

Several open-source hardware for embedded and wireless sensor network systems
Arduino Uno DIP V3 Arduino Starter Kit K000007
Raspberry Pi Compute Module
Raspberry Pi 3 Premium Kit
LoRa LoRaWAN Gateway – 868MHz Kit with Raspberry Pi 3
Seeeduino LoRaWAN W/GPS

voltaware-sensor

Voltaware Energy Sensor for wireless energy monitor
– Proprietary single-phase and three-phase power monitoring sensors
– Capable of monitoring of individual appliances
– Suitable for building energy management
– Integrated with proprietary machine intelligence for power disaggregation