Abstract:
The present disclosure relates to a thermal dissipation system of an electric vehicle that includes: a heat exchanger arranged at the front part of the electric vehicle for providing heating or cooling to an air conditioning system of the electric vehicle; a first heat sink and a second heat sink, which are respectively arranged at the two sides of the front part of the heat exchanger; a number of rotatable and adjustable air deflectors for changing the flow direction of the air flowing through the heat dissipation system. Temperature sensors are included within the thermal dissipation system for sensing the working temperatures and the environmental temperatures of a battery pack and a motor of the electric vehicle. Opening and closing states of the air deflectors are adjusted in accordance with data provided by the temperature sensors.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of Non-Provisional U.S. application Ser. No. 14/842,803, filed Sep. 1, 2015, which claims priority to U.S. Provisional Patent Application No. 62/133,991, filed on Mar. 16, 2015, and U.S. Provisional Patent Application No. 62/150,848, filed on Apr. 22, 2015, the disclosures of which are hereby incorporated by reference in their entireties for all purposes. 
    
    
     BACKGROUND 
     1. Field 
     The present disclosure relates to thermal dissipation systems for electric vehicles. In particular, a thermal dissipation system configured to recapture heat dissipated from other operational components of the electric vehicle is discussed. 
     2. Description of Related Art 
     The present invention relates to an assembly of a heat exchanger used by an air conditioner of an electric vehicle and heat sinks used by a battery and/or a motor. Based on a new design of the electric vehicle, the heat sinks thereof can be arranged on two sides of a front portion of the heat exchanger, in order to enable the heat exchanger to take full advantage of waste heat being dissipated by the heat sinks. There is a need to design particular air deflectors to enable the heat source from the heat sinks to be absorbed into the heat exchanger, so as to provide optimal heat source management under various conditions. 
     SUMMARY 
     To achieve the above purpose, this disclosure describes a thermal dissipation system of an electric vehicle including: a heat exchanger arranged at an air inlet portion of the electric vehicle for the heat exchange of an air conditioner of the electric vehicle; a first heat sink and a second heat sink, which are respectively arranged at the two sides of the front part of the heat exchanger; and a plurality of rotatable and adjustable air deflectors for redirecting air as it flows through the heat exchanger, the first heat sink and the second heat sink. 
     According to the invention, a number of sensors are arranged for sensing the working temperatures and the environmental temperatures of a battery pack and a motor. Opening and closing states of the air deflectors can be adjusted under different operating states of the air conditioner and different temperatures of the battery pack and the motor, thereby enabling the heat energy dissipated from the first heat sink and the second heat sink to be utilized in an efficient manner 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a control module diagram of a heat dissipation system in accordance with an exemplary embodiment of the present disclosure; 
         FIG. 2A  is a schematic diagram of a working mode I of air deflectors in accordance with an exemplary embodiment of the present disclosure; 
         FIG. 2B  is a schematic diagram of a working mode II of the air deflectors in accordance with an exemplary embodiment of the present disclosure; 
         FIG. 2C  is a schematic diagram of a working mode III of the air deflectors in accordance with an exemplary embodiment of the present disclosure; 
         FIG. 2D  is a schematic diagram of a working mode IV of the air deflectors in accordance with an exemplary embodiment of the present disclosure; and 
         FIG. 3  is a schematic diagram of a control flow of the heat dissipation system in accordance with an exemplary embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments of the present invention will be described below with reference to accompanying drawings constituting a part of the description. It should be understood that, although terms, such as “front”, “rear”, “upper”, “lower”, “left”, “right” and the like, representing directions are used in the present invention for describing various exemplary structural parts and elements of the present invention, these terms are used herein only for the purpose of convenience of explanation and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed by the present invention can be arranged according to different directions, these terms representing directions are merely used for illustration and should not be regarded as limitation. Wherever possible, the same or similar reference marks used in the present invention refer to the same components. 
       FIG. 1  is a control module diagram of a heat dissipation system in accordance with an exemplary embodiment of the present disclosure. 
     As shown in  FIG. 1 , the control system of the heat dissipation system in the present invention at least includes: a controller  101  (provided with a CPU  102  therein), an air conditioner state input  103 , a battery pack temperature monitor  104 , motor temperature sensors  105 , a battery pack environment temperature sensor  110 , a motor environment temperature sensor  112 , a first air deflector drive  106 , a second air deflector drive  107 , a third air deflector drive  108 , a battery pack heater  109 , a first air deflector  111 , second air deflectors  121 , third air deflectors  131  and so on. 
     The air conditioner state input  103  can be used for inputting the working states of a vehicle cabin air conditioner, which include the following three states: refrigerating, heating and turned off The air conditioner state input  103  can take many forms including for example a multi-position switch allowing a user to manually select one of the states. In some embodiments, the air conditioner state input  103  can take the form of a controller that varies the vehicle cabin air conditioner between states to maintain a desired cabin air temperature. The battery pack temperature monitor  104  is arranged in the battery pack for sensing a temperature T b  in the battery pack; the battery pack temperature monitor  104  is made up of multiple motor temperature sensors  105  arranged at positions having the highest temperatures in the driving parts of the motor, which can include for example a motor drive, a gear box and the like. A motor working temperature T m  is defined as the average value of the highest temperature readings of these parts. The battery pack environment temperature sensor  110  is arranged at the outside of the battery pack for sensing an environment temperature T 3  at the outside of the battery pack. The motor environment temperature sensor  112  is arranged at the outside of the driving parts of the motor, the motor drive, the gear box and the like for sensing the environment temperature T 4  at the outside of the driving parts. All of the temperature sensors mentioned above are connected to the controller  101  and can periodically or continuously send the sensed temperatures to the controller  101 . 
     The first air deflector  111 , the second air deflectors  121  and the third air deflectors  131  are respectively arranged behind an air inlet portion of the vehicle (specifically as shown in  FIG. 2A  to  FIG. 2D ). As an embodiment, the air deflector can be of a louver structure, and the air deflector can be in an open, half-open or closed state by virtue of a rotation of the blades of the louver. In the present invention, the embodiments of the present invention are illustrated just by taking the open and closed states as examples; however, the half-open state of the air deflector is also encompassed in the conception of the present invention and can provide various embodiments in which air flow is even further fine-tuned or adjusted to accomplish a desired cooling or heating configuration. For example, in some embodiments, individual vents or subsets of vents of an air deflector could be turned at different angles to customize a flow of air through the air deflector. 
     When the vehicle is in operation, air can pass through the opened air deflectors. Each of the air deflectors is provided with a drive, namely the first air deflector drive  106 , the second air deflector drive  107  and the third air deflector drive  108 . The drives can be electric motors (omitted from the figure) for respectively driving the first air deflector  111 , the second air deflectors  121  and the third air deflectors  131 . The first air deflector drive  106 , the second air deflector drive  107  and the third air deflector drive  108  are also connected to the controller  101 . The controller  101  respectively sends a control signal to the above-mentioned drives, and the drives control the opening and closing of the air deflectors when at work. 
     When the temperature of the battery pack is too low, the controller  101  sends a control signal to the battery pack heater  109 , and the battery pack heater  109  works to raise the temperature of the battery pack. 
     As shown in  FIGS. 2A-2D , a first heat sink  220 , a heat exchanger  210  and a second heat sink  230  are arranged at the front of the vehicle body or in any portion of the vehicle body configured to receive incoming air. The first heat sink  220  and the second heat sink  230  are respectively arranged at two sides of the front part of the heat exchanger  210 . The heat exchanger  210  can be a heat exchanger associated with the cabin air conditioner. When the air conditioner is refrigerating, the heat exchanger  210  is configured to dissipate heat, and when the air conditioner is heating, the heat exchanger is configured to absorb heat. When the heat exchanger  210  transitions between heating and cooling configurations, various heating and/or cooling system components can adjust a temperature of cooling/heating elements of the heat exchanger  210 . The first heat sink  220  and the second heat sink  230  can be respectively the heat sinks of the motor and the battery pack. 
     The first air deflector  111 , the second air deflectors  121  and the third air deflectors  131  are respectively arranged between two of the first heat sink  220 , the heat exchanger  210  and the second heat sink  230 . Specifically, the first air deflector  111  is arranged in front of the heat exchanger  210 , and the two ends of the first air deflector  111  are respectively connected with the right end of the first heat sink  220  and the left end of the second heat sink  230 . In some embodiments, a central portion of the first air deflector  111  can include a protrusion that helps to smoothly split air contacting the central portion of the first air deflector  111  when the first air deflector  111  is closed. The second air deflectors  121  includes two deflectors, a left second air deflector  121 . 1  and a right second air deflector  121 . 2 , the two ends of the left second air deflector  121 . 1  are respectively connected with the right end of the first heat sink  220  and the left end of the heat exchanger  210 , and the two ends of the right second air deflector  121 . 2  are respectively connected with the right end of the heat exchanger  210  and the left end of the second heat sink  230 ; the third air deflectors  131  includes two deflectors, a left third air deflector  131 . 1  and a right third air deflector  131 . 2 , the left third air deflector  131 . 1  is arranged behind the first heat sink  220 , and the two ends of the left third air deflector are respectively connected with the left end of the first heat sink  220  and the left end of the heat exchanger  210 ; the right third air deflector  131 . 2  is arranged behind the second heat sink  230 , and the two ends of the right third air deflector are respectively connected with the right end of the second heat sink  230  and the right end of the heat exchanger  210 . 
     When the vehicle is in operation, air  250  enters into the vehicle and when the first air deflector  111  is open (indicated by a dotted line as depicted in  FIGS. 2A-2B ), the air can pass through air deflector  111  to flow directly through the heat exchanger  210 . When the second air deflectors  121  are closed (indicated by solid lines), the air exiting the first heat sink  220  and the second heat sink  230  cannot flow into the heat exchanger  210 . When the third air deflectors  131  are closed and the second air deflectors  121  are open (as depicted in  FIG. 2B ), the air can flow from the first heat sink  220  and the second heat sink  230  to the heat exchanger  210 , thereby substantially increasing an average temperature of the air entering the heat exchanger  210 . 
     According to the temperatures of the motor and the battery pack and different states of the cabin air conditioner, the opening and closing of the air deflectors can be adjusted to optimally distribute the heat dissipated by the first heat sink  220  and the second heat sink  230 . In some states, at least some of the heat dissipated by the first heat sink  220  and the second heat sink  230  can be transferred to the heat exchanger  210 . The following figures will depict four different working modes that can be assumed by fully opening or closing the air deflectors air deflectors of the thermal dissipation system. 
       FIG. 2A  shows the working mode I of the air deflectors and how the air deflectors affect the incoming air flow. 
     In mode I, the first air deflector  111  and the third air deflectors  131  are open, the second air deflectors  121  are closed causing the air  250  entering the vehicle to pass through the first heat sink  220 , the heat exchanger  210  and the second heat sink  230  at the same time. Because the second air deflectors  121  are closed, the portion of air  250  passing through the first heat sink  220  and the second heat sink  230  is prevented from passing through the heat exchanger  210 . This mode is mainly applicable to the condition that the cabin air conditioner is refrigerating. By means of such an arrangement of the air deflectors in this mode, the heat dissipation of the battery pack and the motor has no influence on the refrigeration of the cabin air conditioner while ensuring the heat dissipation effect of the battery pack and the motor. 
       FIG. 2B  shows the working mode II of the air deflectors and how the air deflectors affect the incoming air flow. 
     In this mode, the first air deflector  111  and the second air deflectors  121  are open, and the third air deflectors  131  are closed. A part of the air  250  passes through the first heat sink  220  and the second heat sink  230  first and then flows through the heat exchanger  210  after being heated by the first heat sink  220  and the second heat sink  230 . A portion of the air  250  passes directly through the heat exchanger  210 . This mode is mainly applicable to the condition that the cabin air conditioner is turned off and the temperatures of the battery pack and the motor are relatively low. By means of such an arrangement of the air deflectors, a portion of the air  250  passes through the first air deflector  111  to reduce the volume of inlet air passing through the first heat sink  220  and the second heat sink  230 . Such a configuration can be beneficial when the battery pack and engine do not require a maximum amount of heat dissipation. This volume of inlet air can ensure the heat dissipation effect of the battery pack and the motor while also allowing an amount of air  250  to engage heat exchanger  210  without having been preheated by either of the heat sinks. 
       FIG. 2C  is a schematic diagram of the working mode III of the air deflectors in the present invention. 
     In this mode, the first air deflector  111  and the second air deflectors  121  are closed, while the third air deflectors  131  are open. In this mode, all the air entering the vehicle only flows through the first heat sink  220  and the second heat sink  230  without passing through the heat exchanger  210 . This mode is mainly applicable to the condition that the cabin air conditioner is turned off and the temperatures of the battery pack and the motor are relatively high. Under this condition, by closing the first air deflector  111  and the second air deflectors  121  and opening the third air deflectors  131 , all the air passes through the first heat sink  220  and the second heat sink  230 , so that the volume of the inlet air passing through the first heat sink  220  and the second heat sink  230  is increased compared with the condition that the first air deflector is open, and this volume of inlet air can increase the heat dissipation effect on the battery pack and the motor when the battery pack and motor are operating at higher temperatures. Such a configuration can also be advantageous as it reduces any backpressure introduced by the thermal dissipation system associated with directing the air through heat exchanger  210 . In this way cooling provided to the battery pack and the engine can be maximized. 
       FIG. 2D  shows the working mode IV of the air deflectors and how the air deflectors affect the incoming air flow. 
     In this mode, the first air deflector  111  and the third air deflectors  131  are closed, the second air deflectors  121  are open, and all the air entering the vehicle flows through the first heat sink  220  and the second heat sink  230  first and then flows through the heat exchanger  210  after being heated. This mode is mainly applicable to the condition that the cabin air conditioner is heating. Under this condition, by closing the first air deflector in front of the heat exchanger  210 , the air firstly flows through the first heat sink  220  and the second heat sink  230  to absorb the heat dissipated from the battery pack and the motor and then transfers some of the absorbed heat to the heat exchanger  210 , such that the heat exchanger  210  can effectively utilize the heat dissipated from the battery pack and the motor to provide warm air to the cabin. 
       FIG. 3  shows one manner in which a controller can be configured to switch between each of the four working modes in accordance with an operating state of the air conditioner and various temperature sensor readings. 
       FIG. 3  is a schematic diagram of the control flow of the thermal dissipation system in the present invention. The controller  101  executes the steps as shown in  FIG. 3 . At Step  301 , the thermal dissipation system of the electric vehicle is started. Step  302  includes receiving a state signal of the air conditioner inputted via the air conditioner state input  103 . At step  303 , the following operations are executed in accordance with the state signal of the air conditioner received in step  302 . 
     Heating State: 
     At step  304 , a battery pack temperature T b  is received by a signal transmitted by a battery pack temperature sensor  104 . 
     At step  305 : judging whether the battery pack temperature T b  is lower than the lower limit T 1  (the first preferable temperature of T 1  is 8° C., and the second preferable temperature of T 1  is 0° C.) of a preferable temperature range of the battery pack according to the temperature signal received in step  304 ; if yes, executing step  306 ; if no, executing step  317 . 
     At step  306 , sending a control signal to the battery pack heater  109  to drive the battery pack heater  109  to work in order to increase the battery pack temperature T b , and then repeating step  304 . 
     At step  317 , sending a control signal to the first air deflector drive  106 , the second air deflector drive  107  and the third air deflector drive  108  to make the air deflectors ( 111 ,  121 ,  131 ) operate in mode IV. 
     Turned Off State: 
     At step  307 , receiving a battery pack temperature T b  signal inputted by the battery pack temperature sensor  104 . 
     At step  308  determining whether the battery pack temperature T b  is between the upper limit T 2  (the first preferable temperature of T 2  is 25° C., the second preferable temperature of T 2  is 35° C. and the third preferable temperature of T 2  is 45° C.) and the lower limit T 1  of the preferable temperature range of the battery pack according to the battery pack temperature signal received in step  307 . When T b ≦T 1  indicating the battery is operating below the preferable temperature range, executing step  309 . When T 1 &lt;T b &lt;T 2  indicating the battery is operating within the preferable temperature range, executing step  310 . When T b ≧T 2  indicating the battery is operating above the preferable temperature range executing step  316 . 
     At step  309 , sending a control signal to the battery pack heater  109  to drive the battery pack heater  109  to work in order to raise the battery pack temperature T b  up towards T 1 , and then repeating step  308 . 
     At step  310 , receiving a battery pack environment temperature T 3  signal inputted by a battery pack environment temperature sensor  110 ; 
     At step  311 , judging whether the battery pack temperature T b  is higher than the battery pack environment temperature T 3  according to the battery pack temperature T b  signal received in step  307  and the battery pack environment temperature T 3  signal received in step  310 ; if yes, executing step  316 , if no, executing step  312 ; 
     At step  312 , receiving a motor working temperature T m  signal and a motor environment temperature T 4  signal inputted by the motor temperature sensor  105  and the motor environment temperature sensor  112 ; 
     At step  313 : judging whether the motor working temperature T m  is higher than the motor environment temperature T 4  according to the motor working temperature T m  signal and the motor environment temperature T 4  signal received in step  312 ; if yes, executing step  316 , if no, executing step  315 ; 
     At step  315 : sending a control signal to the first air deflector drive  106 , the second air deflector drive  107  and the third air deflector drive  108  to make the air deflectors ( 111 ,  121 ,  131 ) be in mode II; 
     At step  316 : sending a control signal to the first air deflector drive  106 , the second air deflector drive  107  and the third air deflector drive  108  to make the air deflectors ( 111 ,  121 ,  131 ) be in mode III; and 
     Refrigerating State: 
     At step  314 , sending a control signal to the first air deflector drive  106 , the second air deflector drive  107  and the third air deflector drive  108  to arrange the air deflectors ( 111 ,  121 ,  131 ) in accordance with mode I; 
     The flowcharts of determining different modes of the air deflectors ( 111 ,  121 ,  131 ) are described above, in order to achieve the comprehensive utilization of energy sources among the first heat sink  220 , the second heat sink  230  and the heat exchanger  210  to optimally manage the energy sources. 
     Although the present invention has been described with reference to the specific embodiments shown in the accompanying drawings, it should be understood that the thermal dissipation system of electric vehicles provided by the present invention can have a variety of variations without departing from the spirit, scope and background of the present invention. Those of ordinary skill in the art should be still aware that, parameters in the embodiments disclosed by the present invention can be changed in different manners, and these changes shall fall within the spirit and scope of the present invention and the claims.