Patent Publication Number: US-2023143231-A1

Title: Power integration system with motor drive and battery charging and discharging function

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This patent application claims the benefit of U.S. Provisional Patent Application No. 63/276,866, filed Nov. 8, 2021, which is incorporated by reference herein. 
    
    
     BACKGROUND 
     Technical Field 
     The present disclosure relates to a power integration system, and more particularly to a power integration system with motor drive and battery charging and discharging. 
     Description of Related Art 
     The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art. 
     The current light electric vehicle system includes a motor driver and a charger, wherein the charger is divided into the on-board charger and the off-board charger. Since the chargers have different battery specifications, various manufacturers will introduce dedicated off-board chargers for users to use, and the disadvantage is that the chargers are not compatible with different vehicles, which makes it inconvenient to carry. 
     SUMMARY 
     An objective of the present disclosure is to provide a power integration system with motor drive and battery charging and discharging function to solve the problems of existing technology. 
     In order to achieve the above-mentioned objective, the power integration system with motor drive and battery charging and discharging function includes a motor, a power integration circuit, and a battery. The power integration circuit includes an inverter and a charger. The inverter includes multi-phase bridge arms. Each bridge arm includes an upper switch and a lower switch, and each bridge is correspondingly coupled to each phase winding of the motor. The charger includes a front-end DC conversion path, and the upper switch and the lower switch of at least one bridge arm of the shared inverter. The battery is coupled to the power integration circuit. The power integration circuit receives a DC power provided by a DC power apparatus, and the charger converts the DC power to charge the battery, and the battery provides power required to drive the motor through the inverter. 
     In one embodiment, the battery provides power required by a power-receiving apparatus through the charger, or the power-receiving apparatus charges the battery through the charger. 
     In one embodiment, the front-end DC conversion path includes a front-end bridge arm and a first energy-storing inductor. The front-end bridge arm is coupled to the shared upper switch and lower switch. The first energy-storing inductor is coupled to the front-end bridge arm. The charger further includes a charging unit. The charging unit includes a second energy-storing inductor and a sub path. The second energy-storing inductor is coupled to the shared upper switch and lower switch. The sub path is coupled to the second energy-storing inductor. 
     In one embodiment, the front-end bridge arm includes a first switch and a second switch. A common-connected node of the first switch and the second switch is coupled to a first end of the first energy-storing inductor, and a second end of the first energy-storing inductor is coupled to the battery. The sub path includes a third switch. A first end of the third switch is coupled to an end, which is not commonly coupled to the upper switch, of the lower switch, and a second end of the third switch is coupled to the DC power apparatus. 
     In one embodiment, the front-end bridge arm includes a first switch and a second switch. A common-connected node of the first switch and the second switch is coupled to a first end of the first energy-storing inductor, and a second end of the first energy-storing inductor is coupled to the battery. The sub path includes a third switch. A first end of the third switch is coupled in series to the second energy-storing inductor, and a second end of the third switch is coupled to the DC power apparatus. 
     In one embodiment, the front-end bridge arm includes a first switch and a second switch. A common-connected node of the first switch and the second switch is coupled to a first end of the first energy-storing inductor, and a second end of the first energy-storing inductor is coupled to the battery. The sub path includes a first diode. An anode of the first diode is coupled to an end, which is not commonly coupled to the upper switch, of the lower switch, and a cathode of the first diode is coupled to the DC power apparatus. 
     In one embodiment, when a voltage of the battery is greater than a reference voltage value, the charging unit operates in a boost mode to charge the battery, and when the voltage of the battery is less than the reference voltage value, the charging unit operates in a buck mode to charge the battery. 
     In one embodiment, the battery provides power required by a power-receiving apparatus through the charger, or the power-receiving apparatus charges the battery through the charger, and according to the power required by the power-receiving apparatus, the charging unit makes the battery operate in a boost mode or a buck mode to discharge to the power-receiving apparatus. 
     In one embodiment, the front-end DC conversion path includes a front-end bridge arm and a first energy-storing inductor. The front-end bridge arm is coupled to the shared upper switch and lower switch. The first energy-storing inductor is coupled to the front-end bridge arm. The charger further includes a charging unit. The charging unit includes a plurality of second energy-storing inductors and a sub path. The second energy-storing inductors are correspondingly coupled to the shared upper switches and lower switches. The sub path is coupled to the second energy-storing inductors. 
     Accordingly, the power integration system with motor drive and battery charging and discharging function is provided to realize the structure that the power switches of a three-phase motor driver are shared in the charger, which can reduce the number of external components, thereby reducing the size and achieving high efficiency. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the present disclosure as claimed. Other advantages and features of the present disclosure will be apparent from the following description, drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The present disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawing as follows: 
         FIG.  1    is a block diagram of a power integration system with motor drive and battery charging and discharging function used with a DC power apparatus and a power-receiving apparatus according to the present disclosure. 
         FIG.  2    is a block diagram of the power integration system with motor drive and battery charging and discharging function used with the DC power apparatus according to the present disclosure. 
         FIG.  3    is a block circuit diagram of the power integration system with motor drive and battery charging and discharging function according to a first embodiment of the present disclosure. 
         FIG.  4    is a block circuit diagram of a charger in  FIG.  3    according to a first embodiment of the present disclosure. 
         FIG.  5    is a block circuit diagram of the charger in  FIG.  3    according to a second embodiment of the present disclosure. 
         FIG.  6    is a block circuit diagram of the charger in  FIG.  3    according to a third embodiment of the present disclosure. 
         FIG.  7    is a block circuit diagram of the power integration system with motor drive and battery charging and discharging function according to a second embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made to the drawing figures to describe the present disclosure in detail. It will be understood that the drawing figures and exemplified embodiments of present disclosure are not limited to the details thereof. 
     Due to the versatility of Type-C transmission cables and the convenience of USB-PD chargers, the present disclosure proposes an integrated (shared components) bidirectional charger structure as shown in  FIG.  1   , which combines the traditional three-phase motor driver and charger to form an integration system. The system can be directly connected to an external USB-PD through a Type-C transmission line for charging. In addition to the charging function, the battery energy can also be provided to external apparatuses (or power-receiving apparatuses) through Type-C transmission cables, such as but not limited to light electric vehicles (such as electric scooters, electric bicycles, electric wheelchairs, electric skateboards, etc.). Accordingly, the power integration system with motor drive and battery charging and discharging function is provided to realize the structure that the power switches of a three-phase motor driver are shared in the charger, which can reduce the number of external components, thereby reducing the size and achieving high efficiency. 
     Please refer to  FIG.  1   , which shows a block diagram of a power integration system with motor drive and battery charging and discharging function used with a DC power apparatus and a power-receiving apparatus according to the present disclosure. The power integration system with motor drive and battery charging and discharging function (hereinafter referred to as the power integration system) includes a motor  10 , a power integration circuit  20 , and a battery  30 . The power integration circuit  20  includes an inverter  21  and a charger  22 . The inverter  21  has multi-phase (for example, three-phase) bridge arms, each phase bridge arm includes an upper switch and a lower switch, and each phase bridge arm is correspondingly coupled to each phase winding of the motor  10 . The charger  22  includes a front-end DC conversion path  22 A and the upper switch and the lower switch of at least one bridge arm of the shared inverter  21 . In other words, the power integration circuit  20  is a shared-component circuit structure having the inverter  21  and the charger  22 . Specifically, the part of the shared component is the upper switch and the lower switch of the at least one bridge arm, and the front-end DC conversion path  22 A, which will be described in detail later. Incidentally, the front-end DC conversion path  22 A of the present disclosure can be, for example but not limited to, a boost converter, a buck converter, a buck-boost converter, or other types of DC-DC converters, which can be designed according to the requirements of practical applications. The battery  30  is coupled to the power integration circuit  20 . 
     The power integration system shown in  FIG.  1    is a bidirectional structure. Therefore, the power integration circuit  20  receives DC power provided by a DC power apparatus  40 , and the charger  22  of the power integration circuit  20  converts the DC power to charge the battery  30  so that the DC power can charge the battery  30 . In one embodiment, the DC power apparatus  40  is, for example, but not limited to, USB-PD. Take the light electric vehicle-electric bicycle as an example, the motor  10 , the power integration circuit  20 , and the battery  30  are installed (disposed) inside the electric bicycle, and the DC power provided by the DC power apparatus  40  is an external USB-PD DC power. Therefore, when the electric bicycle is plugged into the USB-PD DC power for charging, the charger  22  of the power integration circuit  20  converts the USB-PD DC power to charge the battery  30  installed inside the vehicle body of the electric bicycle. 
     Moreover, the battery  30  provides power required by a power-receiving apparatus  50  through the charger  22 . As mentioned above, the power-receiving apparatus  50  is, for example, but not limited to, a portable mobile apparatus (such as a mobile phone, a tablet computer, a notebook computer, etc.). When the user is outdoors, the user can plug a mobile phone, a power bank, or an electric bicycle (i.e., the power-receiving apparatus  50 ) into the charger  22  of the power integration circuit  20  installed inside another electric bicycle for charging, the battery  30  supplies (provides) the power required by the mobile phone through the charger  22  to charge the mobile phone, the power bank, or the electric bicycle. 
     Moreover, the battery  30  provides power required to drive the motor  10  through the inverter  21 . When the user rides the electric bicycle outdoors, the power required to drive the motor  10  is supplied by the battery  30 . 
     Moreover, the power-receiving apparatus  50  charges the battery  30  through the charger  22 . When the electric bicycle is not in the riding state and no DC power (the USB-PD DC power) provided by the DC power apparatus  40  charges the battery  30 , the battery  30  is charged by the power provided from the power-receiving apparatus  50  (i.e., the mobile phone, the power bank, or the electric bicycle). For example, when the user rides the electric bicycle outdoors and the battery  30  cannot provide the power required by the electric bicycle, the battery  30  can be charged by the power provided from the power-receiving apparatus  50  so that the electric bicycle can be ridden in a short time to the nearest place with the DC power apparatus  40  to be fully charged. 
     Therefore, the power integration system shown in  FIG.  1    provides a bidirectional power path, including that the DC power apparatus  40  charges the battery  30  or the power-receiving apparatus  50  charging the battery  30 , and the battery  30  supplies power to the power-receiving apparatus  50  or the battery  30  supplies power to the motor. 
     Please refer to  FIG.  2   , which shows a block diagram of the power integration system with motor drive and battery charging and discharging function used with the DC power apparatus according to the present disclosure. The major difference between the embodiment shown in  FIG.  2    and the embodiment shown in  FIG.  1    is that the former does not have the power-receiving apparatus  50 . In other words, the power integration system shown in  FIG.  2    is applied (operated) without the power-receiving apparatus  50 . Therefore, the power integration system shown in  FIG.  2    provides a unidirectional power path, including the DC power apparatus  40  charging the battery  30 , and the battery  30  supplying power to the motor  10 . For other operations that are the same as those of the first embodiment shown in  FIG.  1   , refer to the foregoing description, and the detail description is omitted here for conciseness. 
     Please refer to  FIG.  3   , which shows a block circuit diagram of the power integration system with motor drive and battery charging and discharging function according to a first embodiment of the present disclosure. The front-end DC conversion path  22 A includes a front-end bridge arm  221  and a first energy-storing inductor L 4 . The front-end bridge arm  221  is coupled to the shared upper switch Q 5  and lower switch Q 6 . The first energy-storing inductor L 4  is coupled to the front-end bridge arm  221 . The charger  22  further includes a charging unit  22 B. The charging unit  22 B includes a second energy-storing inductor L 5  and a sub path  222 . 
     Please refer to  FIG.  4   , which shows a block circuit diagram of a charger in  FIG.  3    according to a first embodiment of the present disclosure. The front-end bridge arm  221  includes a first switch Q 7  and a second switch Q 8 . A common-connected node of the first switch Q 7  and the second switch Q 8  is coupled to a first end of the first energy-storing inductor L 4 , and a second end of the first energy-storing inductor L 4  is coupled to the battery  30 . The sub path  222  includes a third switch Q 9 . A first end of the third switch Q 9  is coupled to an end, which is not commonly coupled to the upper switch Q 5 , of the lower switch Q 6 , and a second end of the third switch Q 9  is coupled to the DC power apparatus  40 . 
     Please refer to  FIG.  5   , which shows a block circuit diagram of the charger in  FIG.  3    according to a second embodiment of the present disclosure. The front-end bridge arm  221  includes a first switch Q 7  and a second switch Q 8 . A common-connected node of the first switch Q 7  and the second switch Q 8  is coupled to a first end of the first energy-storing inductor L 4 , and a second end of the first energy-storing inductor L 4  is coupled to the battery  30 . The sub path  222  includes a third switch Q 9 . A first end of the third switch Q 9  is coupled in series to the second energy-storing inductor L 5 , and a second end of the third switch Q 9  is coupled to the DC power apparatus  40 . 
     Please refer to  FIG.  6   , which shows a block circuit diagram of the charger in  FIG.  3    according to a third embodiment of the present disclosure. The front-end bridge arm  221  includes a first switch Q 7  and a second switch Q 8 . A common-connected node of the first switch Q 7  and the second switch Q 8  is coupled to a first end of the first energy-storing inductor L 4 , and a second end of the first energy-storing inductor L 4  is coupled to the battery  30 . The sub path  222  includes a first diode Di. An anode of the first diode Di is coupled to an end, which is not commonly coupled to the upper switch Q 5 , of the lower switch Q 6 , and a cathode of the first diode Di is coupled to the DC power apparatus  40 . 
     For the circuits shown in  FIG.  4    and  FIG.  5   , when a voltage of the battery  30  is greater than a reference voltage value, the charging unit  22 B operates in a boost (step-up) mode to charge the battery  30 , and when the voltage of the battery  30  is less than the reference voltage value, the charging unit  22 B operates in a buck (step-down) mode to charge the battery  30 . When the voltage of battery is equal to a reference voltage value, the charging unit  22 A provide the same voltage to charge the battery. Moreover, according to the power required by the power-receiving apparatus  50 , the charging unit  22 B makes the battery  30  operate in a boost (step-up) mode or a buck (step-down) mode to discharge to the power-receiving apparatus  50 . For the circuit shown in  FIG.  6   , the major difference between  FIG.  4   ,  FIG.  5    and  FIG.  6    is that the charging unit  22 B operates in the boost (step-up) mode or the buck (step-down) mode to charge the battery  30 , but the battery  30  cannot discharge to the power-receiving apparatus  50 . 
     Moreover, the battery  30  provides power required by the power-receiving apparatus  50  through the charger  22 , or the power-receiving apparatus  50  charges the battery  30  through the charger  22 . Moreover, according to the power required by the power-receiving apparatus  50 , the charging unit  22 B makes the battery  30  operate in a boost (step-up) mode or a buck (step-down) mode to discharge to the power-receiving apparatus  50 . 
     Please refer to  FIG.  7   , which shows a block circuit diagram of the power integration system with motor drive and battery charging and discharging function according to a second embodiment of the present disclosure. The front-end DC conversion path  22 A includes a front-end bridge arm  221  and a first energy-storing inductor L 4 . The front-end bridge arm  221  is coupled to the shared upper switch Q 5  and lower switch Q 6 . The first energy-storing inductor L 4  is coupled to the front-end bridge arm  221 . The charger  22  further includes a charging unit  22 B. The charging unit  22 B includes a plurality of second energy-storing inductors L 5  and a sub path  222 . The second energy-storing inductors L 5  are correspondingly coupled to the shared upper switches Q 3 , Q 5  and lower switches Q 4 , Q 6 . The sub path  222  is coupled to the second energy-storing inductors L 5 . In particular, the inductance value of each second energy-storing inductor L 5  may be designed to be the same or different according to the actual requirements of the circuits. 
     For the circuit shown in  FIG.  7   , when a voltage of the battery  30  is greater than a reference voltage value, the charging unit  22 B operates in a boost (step-up) mode to charge the battery  30 , and when the voltage of the battery  30  is less than the reference voltage value, the charging unit  22 B operates in a buck (step-down) mode to charge the battery  30 . 
     Moreover, the battery  30  provides power required by the power-receiving apparatus  50  through the charger  22 , or the power-receiving apparatus  50  charges the battery  30  through the charger  22 . Moreover, according to the power required by the power-receiving apparatus  50 , the charging unit  22 B makes the battery  30  operate in a boost (step-up) mode or a buck (step-down) mode to discharge to the power-receiving apparatus  50 . 
     Accordingly, the power integration system with motor drive and battery charging and discharging function is provided to realize the structure that the power switches of a three-phase motor driver are shared in the charger, which can reduce the number of external components, thereby reducing the size and achieving high efficiency. 
     Although the present disclosure has been described with reference to the preferred embodiment thereof, it will be understood that the present disclosure is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the present disclosure as defined in the appended claims.