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The public transport in India is gradually shifting towards electric mobility. Long range in electric mobility can be served with High Voltage Battery (HVB), but HVB can sustain for its designed life if it’s maintained within a specific operating temperature range. Appropriate battery thermal management through Battery Cooling System (BCS) is critical for vehicle range and battery durability This work focus on two aspects, BCS sizing and its coolant flow optimization in Electric bus. BCS modelling was done in 1D CAE software. The objective is to develop a model of BCS in virtual environment to replicate the physical testing. Electric bus contain numerous battery packs and a complex piping in its cooling system. BCS sizing simulation was performed to keep the battery packs in operating temperature range.

In previous work, AC Compressor Cycling (ACC) was modeled by incorporating evaporator thermal inertia in Mobile Air Conditioning (MAC) performance simulation. Prediction accuracy of >95% in average cabin air temperature has been achieved at moderate ambient condition, however the number of ACC events in 1D CAE simulation were higher as compared to physical test [1]. This paper documents the systematic approach followed to address the challenges in simulation model in order to bridge the gap between physical and digital. In physical phenomenon, during cabin cooldown, after meeting the set/ target cooling of a cabin, the ACC takes place. During ACC, gradual heat transfer takes place between cold evaporator surface and air flowing over it because of evaporator thermal inertia.

In the past five years, Indian cities have been consistently appearing in the list of top 15 world’s most polluted cities. Every day, a common man in India spends more than 2 hours on the road due to numerous reasons, thus exposed to inhale highly polluted air. Further, the passenger car users is exposed to ~ 6 times more polluted air as compared to ambient air reason being the air is recirculated through the air conditioning system. Prolonged exposure to such polluted/ recirculated air shows increasing trend in respiratory illnesses, breathing discomfort and fatigue. This paper discusses the key challenges involved in incorporating cabin air filter as cabin air quality enhancer in current mobility solutions.

Electric vehicles (EVs) carries two main anxieties in users which are its range and battery life, hence these are important parameters to be taken care of during electric vehicle development. Range of EV depends on many parameters such as vehicle weight, heating ventilation and air conditioning (HVAC) system, battery cooling system (BCS), traction cooling system (TCS) and other electrical loads, which consumes power from a High Voltage (HV) battery. Severe hot ambient in India requires a big size HVAC system, on the other hand, the battery pack needs refrigerated cooling system to keep its temperature in control. Hence, the major parasitic consumers in an EV are HVAC and BCS. In order to enhance the overall efficiency, a trade-off between these two systems is crucial, as both the systems are served with common compressor and condenser in dual loop refrigerant circuit.

This paper documents the approach followed to simulate the physical phenomenon of thermistor based AC compressor Cut-OFF/Cut-IN (AC compressor cycling) in 1-Dimensional Computer Aided Engineering (1D CAE) to enable Mobile Air Conditioning (MAC) performance prediction at different ambient conditions. Thermistor based AC compressor cycling logic is incorporated in MAC systems to prevent ice formation at evaporator core and liquid refrigerant flow to AC compressor. Currently, during MAC system performance simulation over a transient drive cycle, the 1D models are able to predict cabin cooldown performance for severe ambient conditions (>40°C, high solar load) with >95% accuracy, as in these cases AC compressor cycling due to thermistor doesn’t occur at higher ambient.