CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage application of PCT/EP2018/057955, filed Mar. 28, 2018, and published on Oct. 3, 2019, as WO 2019/185140 A1, all of which is hereby incorporated by reference in its entirety.

The present invention concerns a thermoregulation system for an electrically driven vehicle. The invention also concerns an electrically driven vehicle comprising such a thermoregulation system.

Electric vehicles have very different needs in the field of cooling than diesel vehicles, such as trucks. The batteries that power the electric machine of an all-electrical vehicle, or hybrid vehicle, or fuel-cell powered electrical vehicle require a low temperature to work properly, for example between 20° C. to 35° C., while electric components such as electric machines, inverters, various electrical components called power electronics components electrical machines can support higher temperatures, around 50-60° C. There is therefore a need for a cooling system with two levels of temperature with high constraints on costs, weights, packaging and efficiency, which is difficult to implement in truck architecture.

Usually, the way to obtain two levels of temperature in cooling is to duplicate the coolant circuit loops. However, this implies the use of two pumps, two radiators, two expansion tanks, two sets of fans and many electro valves. These solutions are not optimized in terms of costs, weight, packaging and efficiency.

The aim of the invention is to provide a new thermoregulation system, in which the management of two levels of temperature is obtained with fewer components than in standard systems.

To this end, the invention concerns a thermoregulation system for an electrically driven vehicle, the vehicle comprising:at least one electric machine, andat least one battery for storing electrical energy for powering said at least one electric machine andat least one power electronics component,

the thermoregulation system comprising:a coolant circuit in which circulates a coolant,a pump for circulating the coolant,coolant heat exchangers, connected to the coolant circuit so that the coolant may circulate through them and comprising:a main exchanger, configured for exchanging heat between the coolant and air coming from the outside of the vehicle;at least one battery exchanger, configured for exchanging heat between the coolant and said at least one battery;at least one secondary exchanger, configured for exchanging heat between the coolant and said at least one electric machine and/or said at least one power electronics component.

The thermoregulation system is characterized in that the coolant circuit is divided in:a first branch, which comprises the main exchanger and the at least one battery exchanger,a second branch which comprises the at least one secondary exchanger, the coolant being circulated in parallel in the first and second branches, anda pump branch to which the pump is connected, the pump branch being connected to the first and second branches by an upstream and a downstream connection points so that the coolant circulating in the pump branch is formed by a mix of the coolant circulating in the first branch and of the coolant circulating in the second branch, and is directed towards the first and second branches downstream the pump.

With the implementation of the primary exchanger in the same branch as the battery exchanger, and the electric machine and/or power electronics components exchanger in a distinct branch, the cooling circuit of the battery can get a cooler temperature than the electric machine and/or power electronics components with a circuit that has fewer components, in particular only one pump. This allows a cost, weight and components volume reduction.

According to other aspects of the invention which are advantageous but not compulsory, such a thermoregulation system may incorporate one or several of the following features:The main exchanger is located upstream the at least one battery exchanger.The main exchanger is formed by at least one radiator.The main exchanger is equipped with at least one fan accelerating air passage in the main exchanger.The coolant circuit comprises a bypass line allowing reduction or deactivation of coolant circulation in the main exchanger.The coolant circuit comprises a bypass line allowing isolation of the at least one battery exchanger from the coolant circuit.The thermoregulation system comprises a heating system connected to the second branch and adapted to heat up a conditioned air flow circulating in a driver cabin of the vehicle.The heating system is located downstream the at least one secondary exchanger.The second branch is also connected to at least one supplemental exchanger of the thermoregulation system configured for exchanging heat between the coolant and at least one inverter of the vehicle.The first branch comprises a heat exchanger configured for exchanging heat with at least one low temperature power electronics component of the electrical vehicle.The thermoregulation system comprises at least one control unit adapted to control various working parameters of the thermoregulation system.At least one control unit is adapted to control at least one of:the pump,a fan accelerating air passage in the main exchanger,a valve allowing coolant circulation in a bypass line allowing deactivation of coolant circulation in the main exchanger anda heating system connected to the second branch and adapted to heat up a conditioned air flow circulating in a driver cabin of the vehicle.

The invention also concerns an electrically driven vehicle comprising at least one electric machine and at least one battery for storing electrical energy for powering the at least one electric machine, wherein it comprises a thermoregulation system as mentioned here-above.

