Government regulations and growing concerns regarding global warming has
lead to an increasing number of passenger vehicles on the roads today that are not
powered by the conventional internal combustion (IC) engine. Automotive manufacturers
have introduced electric powertrains over the last 10 years which have
introduced new challenges regarding powering accessory loads historically reliant on
the mechanical energy of the IC engine. High density batteries are used to store
the electrical energy required by an electric powertrain and due to their relatively
narrow acceptable temperature range, require liquid cooling. The cooling system in
place currently utilizes the A/C compressor for cooling and a separate electric element
for heating which is energy expensive when the source of energy is electricity.
The proposed solution is a thermoelectric heat pump for both heating and cooling.
A model predictive controller (MPC) is designed, implemented and tested to
optimize the operation of the thermoelectric heat pump. The model predictive
controller is chosen due to its ability to accept multiple constrained inputs and
outputs as well as optimize the system according to a cost function which may
consist of any parameters the designer chooses. The system is highly non-linear and
complex therefore both physical modelling and system identi cation were used to
derive an accurate model of the system. A steepest descent algorithm was used for
optimization of the cost function.
The controller was tested in a test bench environment. The results show the
thermoelectric heat pump does hold the battery at the speci ed set point however
more optimization was expected from the controller. The controller fell short of
expectation due to operational restriction enforced during design meant to simplify
the problem. The MPC controller is capable of much better performance through
adding more detail to the model, an improved optimization algorithm and allowing
more flexibility in set point selection.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OOSHDU.7 |
| Date | 01 December 2013 |
| Creators | Petryna, Stephen |
| Contributors | Eklund, Mikael, Rohrauer, Greg F. |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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