Control system of electric transport freezing machine, electric transport freezing machine including the same, control method of the same, and control program of the same

Abstract

To provide a control system of an electric transport freezing machine which enables extension of a selectable range of an external power source for driving the electric transport freezing machine mounted on a transport freezing vehicle to improve versatility of the electric transport freezing machine.SOLUTION: A control system of an electric transport freezing machine is applied to an electric transport freezing machine including an inverter, a converter, and a motor compressor and includes: a first interface 301A configured to work with a first external power source 101 which supplies a voltage lower than a predetermined reference voltage value; a second interface 301B configured to work with a second external power source 102 which supplies a voltage higher than the predetermined reference voltage value; and a control 50 which controls whether to drive the first interface or the second interface according to whether the first external power source or the second external power source is connected to the electric transport freezing machine.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a control system for an electric transport refrigeration unit, an electric transport refrigeration unit equipped with the same, a control method for the control system for an electric transport refrigeration unit, and a control program for the control system for an electric transport refrigeration unit. [Background technology]

[0002] Conventionally, for refrigerated transport vehicles used to transport medicines and food, the mainstream system was one equipped with an alternator (generator) and battery dedicated to the electric transport refrigeration unit, as opposed to diesel trucks. In particular, in Europe, in order to increase the penetration rate of electric trucks, it was necessary to newly equip vehicles with an external power source dedicated to the electric transport refrigeration unit.

[0003] Patent Document 1 discloses a refrigeration system for land transportation equipped with two commercial power sources, a second commercial power source that outputs AC 200V power and a first commercial power source that outputs AC 100V power. Furthermore, the controller receives a signal from a phase number detection device that outputs information on the number of power layers of the second commercial power source as a signal, and receives a signal from an AC relay that outputs information on the presence or absence of input from the first commercial power source as a signal. The controller then changes the signal to be output to the power conversion device based on each received signal, thereby controlling the output of the power conversion device.

[0004] Patent Document 2 discloses a transport refrigeration unit that can be operated using either a three-phase 200V AC commercial power source, a single-phase 100V AC household power source, or a battery as its power source. When the household power source is used as the operating power source, the controller determines whether the temperature inside the unit has reached a set temperature, and if the temperature inside the unit has not reached the set temperature, prioritizes cooling operation by the refrigeration unit, and if the temperature inside the unit has reached the set temperature, charges the battery. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4592236 [Patent Document 2] JP 2011-214796 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the external power sources used in Patent Document 1 and Patent Document 2 are only two types, an AC 100V external power source and an AC 200V external power source. In recent years, particularly in Europe, efforts have been made to improve fuel efficiency and energy conservation in transport refrigerated vehicles, making it difficult to newly install alternators (generators) and batteries (storage batteries) dedicated to electric transport refrigeration units in either diesel trucks or EV (Electric Vehicle) trucks. For this reason, there has been an increase in operations in which power is supplied to electric transport refrigeration units from external power sources that are not dedicated to electric transport refrigeration units. For this reason, there is an increasing demand for highly versatile electric transport refrigeration units that can be used in various power source mounting forms.

[0007] The present disclosure has been made in consideration of the above circumstances, and aims to provide a control system for an electric transport refrigeration unit that expands the range of selectable external power sources for driving an electric transport refrigeration unit installed in a transport refrigerated vehicle, thereby improving the versatility of the electric transport refrigeration unit. [Means for solving the problem]

[0008] A control system for an electric transport refrigeration unit according to one aspect of some embodiments of the present disclosure is applied to an electric transport refrigeration unit including an inverter, a converter, and an electric compressor, and includes a first interface corresponding to a first external power supply that supplies a voltage lower than a predetermined reference voltage value, a second interface corresponding to a second external power supply that supplies a voltage higher than a predetermined reference voltage value, and a controller that controls whether the first interface or the second interface is driven depending on whether the first external power supply or the second external power supply is connected to the electric transport refrigeration unit.

[0009] An electric transport refrigeration unit according to one aspect of some embodiments of the present disclosure includes an inverter, a converter, an electric compressor, and a control system for the electric transport refrigeration unit.

[0010] A control method for a control system of an electric transport refrigeration unit according to one aspect of some embodiments of the present disclosure is a control method for an electric transport refrigeration unit that supplies power from an external power source, and includes a step of driving either a first interface corresponding to a first external power source that supplies a voltage lower than a predetermined reference voltage value, or a second interface corresponding to a second external power source that supplies a voltage higher than a predetermined reference voltage value, and a step of controlling whether the first interface or the second interface is to be driven depending on whether the first external power source or the second external power source is connected to the electric transport refrigeration unit.

[0011] A control program for a control system of an electric transport refrigeration unit according to one aspect of some embodiments of the present disclosure is a control method for an electric transport refrigeration unit that supplies power from an external power source, and causes a computer to execute a process of driving either a first interface corresponding to a first external power source that supplies a voltage lower than a predetermined reference voltage value, or a second interface corresponding to a second external power source that supplies a voltage higher than a predetermined reference voltage value, and a process of controlling whether the first interface or the second interface is to be driven depending on whether the first external power source or the second external power source is connected to the electric transport refrigeration unit. Effect of the Invention

[0012] According to the present disclosure, the range of selectable external power sources for driving an electric transport refrigeration unit installed in a transport refrigeration vehicle is expanded, thereby achieving the effect of improving the versatility of the electric transport refrigeration unit. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a side view of a transport refrigeration vehicle equipped with an electric transport refrigeration unit according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a block diagram showing a configuration of an electric transport refrigeration unit according to an embodiment of the present disclosure. [Diagram 3] 2 is a schematic diagram showing an example of a hardware configuration of a control unit of the electric transport refrigeration unit of FIG. 1. [Figure 4] 4 is a functional block diagram showing an example of functions of a control unit in FIG. 3. [Diagram 5] FIG. 1 is a schematic configuration diagram of a control system for an electric transport refrigeration unit according to an embodiment of the present disclosure. [Figure 6] FIG. 6 is a schematic diagram of a power supply path for the electric transport refrigeration unit in FIG. 5 when a low-voltage external power supply is connected to the electric transport refrigeration unit. [Figure 7] FIG. 6 is a schematic diagram of a power supply path for the electric transport refrigeration unit in FIG. 5 when a low-voltage external power supply is connected to the electric transport refrigeration unit and the battery is charged. [Figure 8] 6 is a schematic diagram of a power supply path for the electric transport refrigeration unit in FIG. 5 when an external high-voltage power supply is connected to the electric transport refrigeration unit. FIG. [Figure 9] 6 is a schematic diagram of a power supply path for the electric transport refrigeration unit in FIG. 5 when a commercial power source is connected to the electric transport refrigeration unit. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] (Regarding transport refrigerated vehicles and electric transport refrigeration units) Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic configuration of a transport refrigeration vehicle equipped with an electric transport refrigeration unit according to an embodiment of the present disclosure. FIG. 2 is a block diagram showing the configuration of the electric transport refrigeration unit according to an embodiment of the present disclosure. The transport refrigeration vehicle 1 includes a tractor (vehicle body) 2, a storage shed 3 for storing an object to be transported, and an electric transport refrigeration unit 4 connected to the rear of the tractor 2 and for adjusting the temperature of the space in the storage shed 3. The electric transport refrigeration unit 4 includes a compressor 5 for compressing a refrigerant, a condensing unit 6 for condensing the refrigerant, an evaporator unit 7 for evaporating the refrigerant, a supply unit 30 for supplying power for driving the electric transport refrigeration unit 4, an adjustment unit 40 for adjusting the power supplied from the supply unit 30, and a control unit 50 for controlling each of these electrical components. The compressor 5, the condensing unit 6, and the evaporator unit 7 are connected to each other by piping (not shown) for transporting the refrigerant, thereby forming a refrigeration cycle. The compressor 5 has a different drive type depending on the type of the electric transport refrigeration unit 4.

[0015] The tractor 2 also includes an engine 9 and an alternator 10. The alternator 10 is connected to the engine 9 via a belt, and generates electricity using energy generated by the engine 9 being driven. The electricity generated by the alternator 10 is supplied to the electric transport refrigeration unit 4. The electricity generated by the alternator 10 may also be supplied to a battery (electricity storage unit) 103 included in the transport refrigerated vehicle 1, and used to charge the battery 103. The inverter is an electric circuit that is electrically connected to the generator and generates currents and voltages with different frequencies based on the power generated by the generator. Note that the configuration of the inverter is a known technique, and the known technique may be appropriately adopted.

[0016] The storage shed 3 is a sealable container that is loaded onto the bed of the tractor 2 and used to store transported goods. The storage shed 3 is provided with an evaporator unit 7. The air inside the storage shed 3 is cooled by heat exchange between the evaporator of the evaporator unit 7 and the air inside the storage shed 3.

[0017] The electric transport refrigeration unit 4 includes a compressor 5, a condensing unit 6, an evaporator unit 7, a supply unit 30, an adjustment unit 40, and a control unit 50. The electric transport refrigeration unit 4 drives each device using power supplied from an external power source that is a power source independent of the electric transport refrigeration unit 4. The electric transport refrigeration unit 4 also includes electrical components such as a converter, an inverter, a control board, and a power relay, as described below, and performs power conversion on the power supplied from the external power source to drive each device. The external power source is, for example, a power source attached to the transport refrigerated vehicle 1, an alternator (generator) provided in the transport refrigerated vehicle 1, a storage battery, or a commercial power source that is a power facility at a stop point of the transport refrigerated vehicle 1.

[0018] The condensing unit 6 has an outer shell formed by a box-shaped case fixed to the chassis of the transport refrigerated vehicle 1. The case accommodates a fan (not shown), a fan drive motor (not shown) that rotates the fan, a condenser (not shown) that condenses the high-temperature, high-pressure refrigerant sent from the compressor, a motor (not shown) that drives the compressor, and / or an engine (not shown). The condenser is, for example, a heat exchanger having a heat transfer tube through which the refrigerant flows and fins attached to the heat transfer tube. The refrigerant condenses in the condenser, dissipating heat to the outside air.

[0019] The evaporator unit 7 accommodates within its case a fan (not shown), a fan drive motor (not shown) that rotates the fan, an expansion valve that throttles the refrigerant, an evaporator that evaporates the refrigerant guided from the expansion valve, and the like. The evaporator is, for example, a heat exchanger having a heat transfer tube through which the refrigerant flows and fins attached to the heat transfer tube. The refrigerant evaporates through heat exchange with the evaporator, thereby removing heat from the air inside the refrigerator and cooling the air inside the refrigerator.

[0020] The electric transport refrigeration unit 4 is equipped with a control unit 50 for controlling each electrical component equipped in the electric transport refrigeration unit 4.

[0021] (Regarding the control unit) Fig. 3 is a schematic diagram showing an example of the hardware configuration of the control unit of the electric transport refrigeration unit of Fig. 1. As shown in Fig. 3, the control unit 50 has a computer (computer system) and includes, for example, a CPU 51, an auxiliary storage device (ROM) 52 for storing programs executed by the CPU 51 and data referenced by the programs, a main storage device (RAM) 53 that functions as a work area when each program is executed, a communication interface 54 for connecting to a network, an input / output unit 55 that receives input from an external device and outputs control commands to an external device that can communicate with the control unit 50, and the like. These units are connected, for example, via a bus 56. Examples of the auxiliary storage device 52 include a magnetic disk, a magneto-optical disk, and a semiconductor memory.

[0022] A series of processes for realizing various functions described below is stored in the auxiliary storage device 52 in the form of a program, for example, and the CPU 51 reads this program into the main storage device 53 and executes information processing and arithmetic processing to realize various functions. Note that the program may be pre-installed in the auxiliary storage device 52, provided in a state stored in another computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories.

[0023] Fig. 4 is a functional block diagram showing an example of functions of the control unit in Fig. 3. As shown in Fig. 4, the control unit 50 includes a receiving unit 57, a determining unit 58, and a command unit 59. These components of the control unit 50 shown in Figs. 3 and 4 are capable of electrical communication with each other. The control unit (controller) 50 controls which of a plurality of switching elements is to be driven depending on whether the low-voltage external power supply (first external power supply) 101 or the high-voltage external power supply (second external power supply) 102 is connected to the electric transport refrigeration unit 4. The switching element is, for example, a power relay.

[0024] The reception unit 57 receives user input, which is information for inputting the operating conditions of the electric transport refrigeration unit 4. Here, the user input is, for example, information input by a user, and includes information for specifying whether the external power supply supplying power to the electric transport refrigeration unit 4 is a high-voltage output or a low-voltage output. The user input may, for example, input whether the output voltage of the external power supply is high voltage or low voltage, or the output voltage of the external power supply may be directly input, or model information of the external power supply may be input. The user input may be anything that can specify the output voltage of the external power supply that supplies power to the electric transport refrigeration unit 4, and may be changed as appropriate.

[0025] Furthermore, when the electric transport refrigeration unit 4 is equipped with a detector (not shown) that detects the output voltage of the external power supply, the reception unit 57 may receive a detection signal from the detector instead of a user input. Note that the detector and detection signal are not limited to voltage, and may be model information of the connected external power supply, etc. Furthermore, when there are multiple external power sources that supply power to the electric transport refrigeration unit 4, information on the operating conditions of each external power source may be received. For example, when the external power source is a battery 103, the receiving unit 57 may receive the current charging rate of the battery 103, the time elapsed since the start of use, the number of charges and discharges up to the present time, and the degree of deterioration.

[0026] The determination unit 58 determines the output voltage of the external power source based on the user input or detection signal received by the reception unit 57. Furthermore, the reception unit 57 determines the power supply path for appropriately driving the electric transport refrigeration unit 4 based on the driving conditions such as the number of external power sources supplying power to the electric transport refrigeration unit 4 and the output performance of each external power source.

[0027] When the reception unit 57 receives a user input, the determination unit 58 determines, based on the user input, the power supply path to appropriately drive the electric transport refrigeration unit 4. For example, when the only external power source supplying power to the electric transport refrigeration unit 4 is an external power source that outputs a low voltage, the determination is made to switch the power supply path of the electric transport refrigeration unit 4 so that only the relay element provided in the power supply path corresponding to the connected external power source is turned on (conductive state) and the relay elements of the other power supply paths are turned off (shutoff state). The determination unit 58 may determine an appropriate power supply path based on the operating conditions of the transport refrigeration unit and the operating conditions of the external power supply accepted by the acceptance unit 57.

[0028] Furthermore, when the receiving unit 57 receives a detection signal from the detector, the determining unit 58 may determine the power supply path for appropriately driving the electric transport refrigeration unit 4 based on the detection signal from the detector. For example, when the detection signal is model information of the external power source, the determination unit 58 refers to a table in which the model information of the external power source and the power supply path correspond to each other, and determines the power supply path corresponding to the external power source. It determines to switch the power supply path of the electric transport refrigeration unit 4 so that only the relay element provided in the power supply path corresponding to the external power source is turned on (conductive state), and the relay elements of the other power supply paths are turned off (cut-off state). The table in which the model information of the external power source and the power supply path correspond to each other may be stored in the auxiliary storage device 52 in advance.

[0029] Also, for example, when the detection signal is the output voltage of the external power source, the determination unit 58 may determine a power supply path that can appropriately supply power in accordance with the output voltage of the external power source. Also, when there are multiple external power sources and the multiple external power sources include a chargeable / dischargeable battery, the determination may be made as to a power supply path that can appropriately supply power, taking into account the charging rate of the battery.

[0030] The command unit 59 outputs a command to switch the power supply path of the electric transport refrigeration unit 4 based on the determination result of the determination unit 58. For example, the electric transport refrigeration unit 4 is provided with a plurality of power supply paths corresponding to each external power source as described below. Furthermore, each power supply path is provided with a power relay as a switching element for conducting or cutting off (on / off) the power supplied from the external power source. In this configuration, the command unit 59 outputs a control command to a configuration for controlling the drive state of each power relay based on the determination result of the determination unit 58, thereby controlling each power supply path to be conducted or cut off. Furthermore, a command unit 59 outputs control commands to the converter and the inverter based on the result of the determination by the determination unit 58. Note that since known techniques can be applied to converter control and inverter control, detailed description will not be given here.

[0031] In addition to having the configuration and functions described above, the control unit 50 controls the electrical components of the electric transport refrigeration unit 4, such as the condensing unit and evaporator unit. Note that known techniques can be applied to control the condensing unit, evaporator unit, and other components of the electric transport refrigeration unit 4, and so will not be described in detail here.

[0032] (Configuration of electric transport refrigeration units) Fig. 5 is a schematic configuration diagram of a control system for an electric transport refrigeration unit according to an embodiment of the present disclosure. As shown in Fig. 5, the control system for an electric transport refrigeration unit in this embodiment includes a first power relay (first interface) 301A corresponding to a low-voltage external power supply (first external power supply) 101, a second power relay (second interface) 301B corresponding to a high-voltage external power supply (second external power supply) 102, and a control unit (controller) 50 that controls whether to drive the first power relay 301A or the second power relay (second interface) 301B depending on whether the low-voltage external power supply 101 or the high-voltage external power supply 102 is connected to the electric transport refrigeration unit.

[0033] The control system of the electric transport refrigeration unit is broadly divided into a supply unit 30 equipped with multiple power relays that switch between the conductive and cut-off states of each power supply path, an adjustment unit 40 that performs conversion processing on the power (more specifically, voltage) supplied from an external power source, and a control unit 50 that drives the electric transport refrigeration unit 4 and controls each of the corresponding components of the electric transport refrigeration unit 4. The driving conditions of the electric transport refrigeration unit 4 are controlled by the supply unit 30, adjustment unit 40 and control unit 50 according to the type and output voltage of the external power source that is the power supply source.

[0034] As shown in FIG. 5, external power sources that supply power to the electric transport refrigeration unit 4 include, for example, an alternator 10, a low-voltage external power source 101, a high-voltage external power source 102, a battery 103, and a commercial power source 104.

[0035] The alternator 10 is a power generation module mounted on the transport refrigerated vehicle 1. The alternator 10 is connected to the engine 9 via a belt, and is a power generation module that generates power when driven by the engine 9 of the transport refrigerated vehicle 1.

[0036] The low-voltage external power supply 101 is an external power supply that supplies a voltage lower than a predetermined reference voltage value. The low-voltage external power supply 101 is, for example, a solar panel, and outputs a voltage of 12 V to 60 V. The reference voltage value may be determined arbitrarily depending on the user's intended use. The reference voltage value may be stored in the auxiliary storage device 52. In addition, in this embodiment, the low-voltage external power source 101 is exemplified by a solar panel, but is not limited to this example, and the low-voltage external power source 101 may be an alternator provided in a transport refrigerated vehicle 1 whose main purpose is not to supply power to the electric transport refrigeration unit 4.

[0037] The high-voltage external power supply 102 is an external power supply that supplies a voltage higher than a predetermined reference voltage value. The high-voltage external power supply 102 is, for example, a lithium-ion battery, and outputs a voltage of 200 V to 800 V. The reference voltage value may be determined arbitrarily depending on the user's intended use. The reference voltage value may be stored in the auxiliary storage device 52.

[0038] The predetermined reference voltage value is set based on the user's usage. For example, it is an intermediate value or a value in an intermediate range between the voltage value that the first external power source can supply and the voltage value that the second external power source can supply. For example, if the range of the voltage value that the first external power source can supply is 12V to 60V and the range of the voltage value that the second external power source can supply is 200V to 800V, the range of the reference voltage value is a value in the range of 61V to 199V.

[0039] The battery 103 is a chargeable and dischargeable battery mounted on the transport refrigerated vehicle 1. The battery 103 can be charged by power generated by the alternator 10 or power supplied from other external power sources. The battery 103 can discharge power to drive the electric transport refrigeration unit 4 according to the charging rate of the battery 103 and the output voltage of other external power sources.

[0040] The commercial power source 104 is a general term for equipment that can be a source of power supply. The commercial power source 104 is, for example, a power facility at a distribution center that is a base for the transport refrigerated vehicle 1 to make deliveries, or a power facility at a stop on the delivery route of the transport refrigerated vehicle 1.

[0041] The supply unit 30 includes a first power relay (first interface) 301A, a second power relay (second interface) 301B, a third power relay (third interface) 301C, a battery charger (auxiliary power storage unit) 302, and a contactor 303.

[0042] The first power relay 301A, the second power relay 301B, and the third power relay 301C are switching elements that are switched on / off by receiving an electric signal from the outside. Here, the first power relay 301A, the second power relay 301B, and the third power relay 301C are selected from those having appropriate physical properties based on the arrangement on the electric circuit, the magnitude of the current of the electric signal received, etc. The power relay may be, for example, a mechanical relay, which is a contact relay, or a MOSFET relay, which is a non-contact relay, etc. Note that the function and configuration of the power relay are not described in detail here because known ones can be applied.

[0043] The first power relay 301A corresponds to the low-voltage external power supply 101 that supplies a voltage lower than a predetermined reference voltage value. When the low-voltage external power supply 101 is mounted on the transport refrigerated vehicle 1, the first power relay 301A receives an electric signal from the control unit 50 as described below and turns to an ON state. When the first power relay 301A turns to an ON state, power supplied from the low-voltage external power supply 101 is supplied to the adjustment unit 40. The power supplied to the adjustment unit 40 is converted into a plurality of predetermined powers corresponding to each of the components of the electric transport refrigeration unit 4 to be supplied with power. Then, each converted power is supplied to each of the components of the electric transport refrigeration unit 4, and the electric transport refrigeration unit 4 is driven under desired conditions. When the low-voltage external power supply 101 is not mounted on the transport refrigerated vehicle 1, the first power relay 301A does not receive an electric signal from the control unit 50 and is in the OFF state.

[0044] The second power relay 301B corresponds to the high-voltage external power supply 102 that supplies a voltage higher than a predetermined reference voltage value. When the high-voltage external power supply 102 is mounted on the transport refrigerated vehicle 1, the second power relay 301B receives an electric signal from the control unit 50 as described below and turns on. When the second power relay 301B turns on, power supplied from the high-voltage external power supply 102 is supplied to the adjustment unit 40. The power supplied to the adjustment unit 40 is converted into a plurality of predetermined powers corresponding to each of the components of the electric transport refrigeration unit 4 to be supplied with power. Then, each converted power is supplied to each of the components of the electric transport refrigeration unit 4, so that the electric transport refrigeration unit 4 operates under desired conditions. When the high-voltage external power supply 102 is not mounted on the transport refrigerated vehicle 1, the second power relay 301B does not receive an electric signal from the control unit 50 and is in the OFF state.

[0045] The third power relay 301C corresponds to the low-voltage external power supply 101. When the low-voltage external power supply 101 is mounted on the transport refrigerated vehicle 1 and the charging rate (SOC: State Of Charge) of the battery 103 is equal to or lower than a preset reference value, the third power relay 301C receives an electric signal from the control unit 50 as described below and turns to an ON state. In addition, the third power relay 301C is connected in series with the battery charger 302. When the third power relay 301C is in an ON state, the battery 103 is charged by power supplied from the low-voltage external power supply 101 until the charging rate of the battery 103 reaches or exceeds a preset reference value. The preset reference value may be arbitrarily determined depending on the intended use of the user. The reference voltage value may be stored in the auxiliary storage device 52.

[0046] Battery charger 302 is a device that adjusts the current and voltage for charging battery 103. Battery charger 302 is disposed between third power relay 301C and battery 103, and suppresses input of inrush current to battery 103 when the dielectric constant of battery 103 is low.

[0047] Moreover, the battery charger 302 includes a first electric wire of a positive electrode and a second electric wire of a negative electrode, and the first electric wire and the second electric wire are preferably electric wires separated from other electric wires, more specifically, from other power supply lines. The battery charger 302 is preferably configured to suppress electrical interference between the electric wires and to improve EMC (Electromagnetic Compatibility). The battery charger 302 is, for example, a converter or a battery charger board, and the functions and detailed configurations of these components are not described in detail here because they may be of known construction.

[0048] The contactor 303 is a switching element that can pass a large current, has a large switching capacity of an electrical contact, and has excellent dielectric strength. The contactor 303 is connected to the commercial power source 104, and the power supplied from the commercial power source 104 is supplied to the adjustment unit 40 via the contactor 303. The function and detailed configuration of the contactor 303 are not described here because known functions and configurations can be applied.

[0049] The adjustment unit 40 includes a DC / DC step-up converter 401, an inverter 402, an AC / DC converter 403, and a DC / DC step-down converter 404. The adjustment unit 40 performs conversion processing on the power supplied from an external power source, and supplies the converted power to each component of the electric transport refrigeration unit 4. In addition, the power supplied to the adjustment unit 40 is converted into a plurality of predetermined powers corresponding to each of the components included in the electric transport refrigeration unit 4 to be supplied with power.

[0050] The DC / DC boost converter 401 boosts the voltage of the power supplied from the external power source when any of the low-voltage external power source 101, the battery 103, or the alternator 10 is connected to the electric transport refrigeration unit 4. For example, when the voltage of the power supplied from the low-voltage external power source 101, the battery 103, or the alternator 10 is 27 V (low voltage), the voltage is converted to 270 V (high voltage) by passing through the DC / DC boost converter 401. The voltage converted by the DC / DC boost converter 401 is supplied to the inverter 402.

[0051] The inverter 402 converts the power supplied from the DC / DC boost converter 401 into power for rotating the compressor 5. The inverter 402 changes the output power based on an electrical signal output from the control unit 50.

[0052] When the commercial power source 104 is connected to the electric transport refrigeration unit 4, the AC / DC converter 403 converts the AC power supplied from the commercial power source 104 via the contactor 303 into DC power. Here, for example, the AC / DC converter 403 converts an AC voltage of 200 V supplied from the commercial power source 104 into a DC voltage of 270 V. A part of the power converted by the AC / DC converter 403 is supplied to the compressor 5 via the inverter 402. In addition, another part of the power converted by the AC / DC converter 403 is stepped down by the DC / DC step-down converter 404 and converted into a DC voltage of 27 V, and then supplied to the control unit 50.

[0053] When the high-voltage external power supply 102 is connected to the electric transport refrigeration unit 4, the DC / DC step-down converter 404 steps down the voltage of the power supplied from the high-voltage external power supply 102. For example, when the voltage of the power supplied from the high-voltage external power supply 102 is 270 V, the voltage is converted to 27 V by passing through the DC / DC step-down converter 404. The power converted by the DC / DC step-down converter 404 is supplied to the control unit 50.

[0054] The control unit 50 includes a low voltage load 501 , a PR driving relay 502 , and a PR driving relay 503 . The control unit 50 controls whether to turn on or off the first power relay 301A, the second power relay 301B, or the third power relay 301C via the PR drive relay 502 or the PR drive relay 503, depending on the type of external power source connected to the electric transport refrigeration unit 4.

[0055] The low voltage load 501 is an electrical component included in the electric transport refrigeration unit 4, and is, for example, a control board, an inductor, a fan, and the like. Furthermore, the low voltage load 501 is, for example, a control board 501A, and is equipped with an FPGA (Field Programmable Gate Array) incorporating a control program that controls the operating conditions of the electric transport refrigeration unit 4. The control board 501A outputs control signals to each component of the electric transport refrigeration unit 4 in order to control the operating conditions of the electric transport refrigeration unit 4. Furthermore, the control board 501A may be equipped with each configuration and function of the control unit 50.

[0056] The PR drive relay 502 is a relay element for switching the first power relay 301A and the second power relay 301B on / off, and outputs a control signal for switching the first power relay 301A and the second power relay 301B on / off to each of the first power relay 301A and the second power relay 301B based on a control command output from the command unit 59. In addition, the drive states of the first power relay 301A and the second power relay 301B are determined by the determination unit 58 based on a user input or a detection result of a detector that changes depending on the type of external power source connected to the electric transport refrigeration unit 4. The relay element used in the PR driving relay 502 is, for example, a small capacity relay or an FET.

[0057] The PR drive relay 503 is a relay element for switching the third power relay 301C on / off, and outputs a control signal for switching the third power relay 301C on / off to the third power relay 301C based on a control command output from the command unit 59. Further, the drive state of the third power relay 301C is determined by the determination unit 58 based on a user input that changes depending on the type of external power source connected to the electric transport refrigeration unit 4 or a detection result from a detector. The relay element used in the PR driving relay 503 is, for example, a small capacity relay or an FET.

[0058] (When using a low-voltage external power supply) An example of control for switching the power supply path of the electric transport refrigeration unit 4 depending on the type and driving state of the external power source connected to the electric transport refrigeration unit 4 will be described below. Figure 6 is a schematic diagram of the power supply path of the electric transport refrigeration unit when a low-voltage external power supply is connected to the electric transport refrigeration unit of Figure 5. In Figure 6, the solid line indicates a connection state in which power is supplied, the dashed line indicates a non-connection state in which power is not supplied, and the two-dot chain line indicates a control signal line. When the low-voltage external power supply 101 is connected to the electric transport refrigeration unit 4, first, the user inputs to the control unit 50 that the external power supply connected to the electric transport refrigeration unit 4 is the low-voltage external power supply 101.

[0059] The control unit 50 first receives a user input through the reception unit 57. Then, based on the received user input, the determination unit 58 determines to turn on the first power relay 301A and turn off the second power relay 301B and the third power relay 301C. Then, a control command is output by the command unit 59 to each of the PR drive relay 502 and the PR drive relay 503 so as to turn on only the first power relay 301A. Then, the first power relay 301A is turned on by the control signal output by the PR drive relay 502. Note that the receiving unit 57 may receive the detection result of the detector and perform the subsequent processes, instead of receiving the user input.

[0060] When only the first power relay 301A is turned on, power supplied from each of the battery 103, the alternator 10, and the low-voltage external power supply 101 is supplied to the DC / DC boost converter 401 of the adjustment unit 40 and the low-voltage load 501 of the control unit 50.

[0061] Further, a part of the power output from each of the battery 103, the alternator 10, and the low-voltage external power supply 101 is supplied to a DC / DC boost converter 401. The power supplied to the DC / DC boost converter 401 is boosted to a predetermined voltage by the DC / DC boost converter 401, and then converted from DC power to AC power by an inverter 402 and supplied to the compressor 5.

[0062] Further, a part of the power output from each of the battery 103, the alternator 10 and the low-voltage external power supply 101 is supplied to the low-voltage load 501 of the control unit 50. In this way, by supplying power to the low-voltage load 501 of the control unit 50, the low-voltage load 501 can output a control command or a control signal to each component of the electric transport refrigeration unit 4.

[0063] In addition, when the low-voltage external power source 101 is mounted on the transport refrigerated vehicle 1, more specifically, at a point before the judgment unit 58 determines which of the first power relay 301A to the third power relay 301C to turn on, the low-voltage load 501 of the control unit 50 may be driven using power supplied from the battery 103 or the alternator 10. Furthermore, with regard to the external power sources that supply power to the electric transport refrigeration unit 4, the battery 103 and the alternator 10 may be used as main power sources, and the low-voltage external power source 101 may be used as an auxiliary power source.

[0064] (When using a high-voltage external power supply to charge the battery) Next, Fig. 7 is a schematic diagram of the power supply path of the electric transport refrigeration unit when a low-voltage external power supply is connected to the electric transport refrigeration unit in Fig. 5 and the battery is charged. In Fig. 7, the solid line indicates the connection state in which power is supplied, the dashed line indicates the non-connection state in which power is not supplied, and the two-dot chain line indicates the control signal line. When the charging rate of the battery 103 is less than a preset reference value, the electric transport refrigeration unit 4 is controlled so that the operation of the compressor 5 is stopped and the battery 103 is charged by the power supplied from the low-voltage external power source 101.

[0065] In this case, the control unit 50 receives a user input or a detection result via the reception unit 57, and determines via the determination unit 58 to turn on the third power relay 301C and turn off the first power relay 301A and the second power relay 301B in order to charge the battery. Then, a command unit 59 outputs a control command to each of the PR drive relay 502 and the PR drive relay 503 so as to turn on only the first power relay 301A. Then, the third power relay 301C is turned on by a control signal output by the PR drive relay 503.

[0066] When the first power relay 301A is turned off and the third power relay 301C is turned on, the power supplied from the low-voltage external power supply 101 is supplied to the battery 103 via the third power relay 301C and the battery charger 302.

[0067] In this way, the control unit 50 switches the power supply path between the low-voltage external power supply 101 and the battery 103 depending on the charging rate of the battery 103. More specifically, when the charging rate of the battery 103 is lower than a preset reference value, the power supply path is switched to one in which the battery charger 302 is provided between the low-voltage external power supply 101 and the battery 103.

[0068] When the charging rate of the battery 103 is less than a preset reference value, a power supply path in which a battery charger 302 is provided between the low-voltage external power supply 101 and the battery 103 is selected, thereby making it possible to prevent an inrush current from being input from the low-voltage external power supply 101 to the battery 103.

[0069] In addition, when the charging rate of the battery 103 is equal to or higher than a preset reference value, the control unit 50 may switch the supply path of power supplied from the low-voltage external power supply 101 by switching on / off each of the power relays 301A to 301C, as shown in FIG. 6, to drive the compressor 5.

[0070] (When using a high-voltage external power supply) Figure 8 is a schematic diagram of the power supply path of the electric transport refrigeration unit when a high-voltage external power supply is connected to the electric transport refrigeration unit of Figure 5. In Figure 8, the solid line indicates a connection state in which power is supplied, the dashed line indicates a non-connection state in which power is not supplied, and the two-dot chain line indicates a control signal line. When the high-voltage external power supply 102 is connected to the electric transport refrigeration unit 4, first, the user inputs to the control unit 50 that the external power supply connected to the electric transport refrigeration unit 4 is the high-voltage external power supply 102.

[0071] The control unit 50 first receives a user input through the reception unit 57. Then, based on the received user input, the determination unit 58 determines to turn on the second power relay 301B and to turn off the first power relay 301A and the third power relay 301C. Then, a control command is output by the command unit 59 to each of the PR drive relay 502 and the PR drive relay 503 so as to turn on only the second power relay 301B. Then, the second power relay 301B is turned on by a control signal output by the PR drive relay 503. Note that the receiving unit 57 may receive the detection result of the detector and perform the subsequent processes, instead of receiving the user input.

[0072] When only the second power relay 301B is turned on, the power supplied from the high-voltage external power supply 102 is supplied to the inverter 402 and the DC / DC step-down converter 404 of the adjustment unit 40. Then, the high AC voltage output from the inverter 402 is supplied to the compressor 5.

[0073] A part of the power output from the high-voltage external power supply 102 is supplied to the inverter 402. The power supplied to the inverter 402 is converted from DC power to AC power by the inverter 402 and is supplied to the compressor 5.

[0074] Further, a portion of the power output from the high voltage external power supply 102 is supplied to a DC / DC step-down converter 404. The power supplied to the DC / DC step-down converter 404 is stepped down to a predetermined voltage by the DC / DC step-down converter 404, and then supplied to a low voltage load 501 of the control unit 50. In this manner, by supplying power to the low voltage load 501 of the control unit 50, the low voltage load 501 of the control unit 50 can output a control command or control signal to each component of the electric transport refrigeration unit 4.

[0075] 8 shows an example in which the battery 103 and the alternator 10 are not connected, the battery 103 and the alternator 10 may be connected to the electric transport refrigeration unit 4 in parallel with the high-voltage external power supply 102. When the high-voltage external power supply 102 is mounted on the transport refrigerated vehicle 1, the battery 103 and the alternator 10 may function as an external power supply in addition to the high-voltage external power supply 102. When the high-voltage external power supply 102 is mounted on the transport refrigerated vehicle 1, more specifically, at a point in time before the determination unit 58 determines which of the first power relay 301A to the third power relay 301C to turn on, the low-voltage load 501 of the control unit 50 may be driven using power supplied from the battery 103 or the alternator 10. Furthermore, with regard to the external power sources that supply power to the electric transport refrigeration unit 4, the battery 103 and the alternator 10 may be used as auxiliary power sources, and the high-voltage external power source 102 may be used as the main power source.

[0076] 8, the external power supply supplying power to the electric transport refrigeration unit 4 is only the high voltage external power supply 102, however, this is not limited to the example, and power may be supplied to the electric transport refrigeration unit 4 from the alternator 10 and the battery 103 in parallel with the high voltage external power supply 102. In this case, the DC / DC boost converter 401 may be driven by the control unit 50.

[0077] (When using commercial power as an external power source) Figure 9 is a schematic diagram of the power supply path of the electric transport refrigeration unit when a commercial power source is connected to the electric transport refrigeration unit of Figure 5. In Figure 9, the solid line indicates a connected state in which power is supplied, and the dashed line indicates a non-connected state in which power is not supplied. For example, when the electric transport refrigeration unit 4 uses the commercial power source 104 installed in a distribution center as an external power source, first, the user inputs to the control unit 50 that the external power source connected to the electric transport refrigeration unit 4 is the commercial power source 104. In this case, the control unit 50 does not control the on / off switching of each of the first power relay 301A to the third power relay 301C.

[0078] In this case, power supplied from commercial power supply 104 is supplied to AC / DC converter 403 via contactor 303. The power supplied to AC / DC converter 403 is converted from AC power to DC power by AC / DC converter 403 and is boosted or stepped down to a predetermined voltage, and then supplied to inverter 402 and DC / DC step-down converter 404.

[0079] A part of the power output from the AC / DC converter 403 is supplied to the inverter 402. The power supplied to the inverter 402 is converted from DC power to AC power by the inverter 402 and is supplied to the compressor 5.

[0080] Further, a portion of the power supplied from the AC / DC converter 403 is supplied to a DC / DC step-down converter 404. The power supplied to the DC / DC step-down converter 404 is stepped down to a predetermined voltage by the DC / DC step-down converter 404, and then supplied to a low-voltage load 501 of the control unit 50. In this manner, by supplying power to the low-voltage load 501 of the control unit 50, the low-voltage load 501 of the control unit 50 can output a control command or control signal to each component of the electric transport refrigeration unit 4.

[0081] As described above, the power supplied from the AC / DC converter 403 is supplied to the inverter 402 and the DC / DC step-down converter 404, similar to the power supplied from the high-voltage external power supply 102 when the high-voltage external power supply 102 is connected to the electric transport refrigeration unit 4, and the power is supplied to the compressor 5 and the control unit 50. Therefore, the inverter 402 and the DC / DC step-down converter 404 can be commonly used regardless of whether the external power supply connected to the electric transport refrigeration unit 4 is the high-voltage external power supply 102 or the commercial power supply 104.

[0082] According to this embodiment, the following effects are obtained. In the control system for the electric transport refrigeration unit of this embodiment, the control unit 50 controls which of the power relays 301A to 301C provided in the power supply path that supplies power to the electric transport refrigeration unit 4 to be driven, depending on the external power source connected to the electric transport refrigeration unit 4. As a result, whether the power supplied from the external power source connected to the electric transport refrigeration unit 4 is high voltage or low voltage, power can be supplied to the electric transport refrigeration unit 4 by switching the drive state of each power relay 301A to 301C corresponding to each voltage. In addition, this allows the electric transport refrigeration unit 4 to be driven without providing a new power source dedicated to the electric transport refrigeration unit 4 in the transport refrigeration vehicle 1. Therefore, the user's selectable range of external power sources can be expanded. In other words, the selectable range of the transport refrigeration vehicle 1 equipped with the electric transport refrigeration unit 4 is expanded, and the versatility of the electric transport refrigeration unit 4 can be improved. In addition, by facilitating the electrification of the electric transport refrigeration unit 4, the environmental resistance of the transport refrigeration vehicle 1 can be improved. The predetermined reference voltage value is set based on the user's usage situation. For example, it is an intermediate value or a value in an intermediate range between the voltage value that the low-voltage external power supply 101 can supply and the voltage value that the high-voltage external power supply 102 can supply. For example, if the range of the voltage value that the low-voltage external power supply 101 can supply is 12V to 60V and the range of the voltage value that the high-voltage external power supply 102 can supply is 200V to 800V, the range of the reference voltage value is a value in the range of 61V to 199V.

[0083] Furthermore, in the control system for the electric transport refrigeration unit of this embodiment, the low-voltage external power supply 101 may be used as an auxiliary power supply corresponding to the load of the electric transport refrigeration unit when driven in parallel with the alternator 10 that supplies power to the electric transport refrigeration unit 4. In this case, the alternator 10 becomes the main power supply for driving the electric transport refrigeration unit, and the first external power supply becomes the auxiliary power supply for driving the electric transport refrigeration unit. This makes it possible to stabilize the power supply to the electric transport refrigeration unit 4 and the drive capacity of the electric transport refrigeration unit 4.

[0084] Furthermore, in the control system for the electric transport refrigeration unit of this embodiment, the low-voltage external power supply 101 is used as a power supply for charging the battery 103 when driven in parallel with the alternator 10 that supplies power to the electric transport refrigeration unit. In this case, the alternator 10 becomes the main power supply for driving the electric transport refrigeration unit 4, and the low-voltage external power supply 101 becomes the power supply for charging the battery. As a result, it is possible to charge the battery 103 while maintaining the supply of power to the electric transport refrigeration unit 4 and the driving capacity of the electric transport refrigeration unit 4, thereby improving power efficiency when driving the electric transport refrigeration unit 4.

[0085] Furthermore, in the control system for the electric transport refrigeration unit of this embodiment, when the high-voltage external power supply 102 is driven in parallel with the alternator 10 that supplies power to the electric transport refrigeration unit 4, it is used as the main power supply corresponding to the load of the electric transport refrigeration unit 4. In this case, the alternator 10 serves as an auxiliary power supply for driving the electric transport refrigeration unit 4, and the high-voltage external power supply 102 serves as the main power supply for driving the electric transport refrigeration unit 4. This makes it possible to stabilize the power supply to the electric transport refrigeration unit 4 and the drive capacity of the electric transport refrigeration unit 4.

[0086] Furthermore, in the control system for the electric transport refrigeration unit of this embodiment, the commercial power supply 104 is used as a power supply that supplies power to the electric transport refrigeration unit 4 in response to the power supplied from the high-voltage external power supply 102 to the electric transport refrigeration unit 4. As a result, when it is not preferable to drive the electric transport refrigeration unit 4 with power from the high-voltage external power supply 102 at a stop location of the transport refrigeration vehicle 1, such as a distribution center, the electric transport refrigeration unit 4 can be stably driven by supplying power from the commercial power supply 104 to the electric transport refrigeration unit 4. Here, the commercial power supply 104 is a power supply that can be externally connected to an electric transport refrigeration unit installed at a stop location of the transport refrigeration vehicle 1, such as a distribution center.

[0087] Furthermore, in the control system of the electric transport refrigeration unit of this embodiment, when the low-voltage external power supply 101 is connected to the electric transport refrigeration unit 4 and the charging rate of the battery 103 is lower than a preset reference value, the third power relay 301C is controlled to be driven instead of the first power relay 301A. Furthermore, the battery charger 302 limits the current flowing to the battery 103 when the charging rate of the battery 103 is low. When the charging rate of the battery 103 is low, there is a risk that a large current, for example an inrush current, will suddenly flow to the battery 103 if the charging rate of the battery 103 is low and charging is performed using power supplied from an external power supply. Therefore, when the charging rate of the battery 103 is low, the battery 103 is charged using power supplied from the battery charger 302 to increase the charging rate. This prevents damage to the battery 103 and allows the battery 103 to be continuously charged.

[0088] Furthermore, in the control system for the electric transport refrigeration unit of this embodiment, the first positive electric wire and the second negative electric wire of the battery charger 302 are electric wires separated from other electric wires. Here, the other electric wires are specifically power supply wires. This prevents the first and second electric wires from interfering electrically with other electric wires through which high power flows. Furthermore, it is possible to improve the EMC (Electromagnetic Compatibility) of the control system for the electric transport refrigeration unit and the circuits included in this control system.

[0089] Although the present disclosure has been described above using the embodiments, the technical scope of the present disclosure is not limited to the scope described in the above embodiments. Various modifications or improvements can be made to the above embodiments without departing from the gist of the present disclosure, and the forms in which such modifications or improvements are made are also included in the technical scope of the present disclosure. In addition, the above embodiments may be appropriately combined. Furthermore, the number and connection state of external power sources connected to the electric transport refrigeration unit 4 are not limited to those in the above embodiment. For example, a plurality of external power sources may be connected in parallel to the electric transport refrigeration unit 4, and power may be supplied to the electric transport refrigeration unit 4 through power supply paths corresponding to each of the external power sources.

[0090] (Additional Notes) The control system for the electric transport refrigeration unit described in the above-mentioned embodiments, the transport refrigeration unit equipped with the same, the control method for the control system for the electric transport refrigeration unit, and the control program for the control system for the electric transport refrigeration unit can be understood, for example, as follows. The control system for an electric transport refrigeration unit according to a first aspect of the present disclosure is applied to an electric transport refrigeration unit including an inverter, a converter, and an electric compressor, and includes a first interface (301A) corresponding to a first external power source (101) that supplies a voltage lower than a predetermined reference voltage value, a second interface (301B) corresponding to a second external power source (102) that supplies a voltage higher than a predetermined reference voltage value, and a controller (50) that controls whether to drive the first interface or the second interface depending on whether the first external power source or the second external power source is connected to the electric transport refrigeration unit.

[0091] According to the control system for the electric transport refrigeration unit of the present disclosure, the controller controls whether to drive the first interface or the second interface depending on whether the first external power source supplying a voltage lower than a reference voltage value or the second external power source supplying a voltage higher than a reference voltage value is connected to the electric transport refrigeration unit. As a result, regardless of whether the power supplied from the external power source connected to the electric transport refrigeration unit is a high voltage or a low voltage, the electric transport refrigeration unit can be driven by driving the interface corresponding to each voltage, without providing a new power source dedicated to the electric transport refrigeration unit. Therefore, the range of external power sources that can be selected by the user can be expanded. In other words, the range of selectable external power sources for transport refrigeration vehicles equipped with the electric transport refrigeration unit can be expanded, and the versatility of the electric transport refrigeration unit can be improved. In addition, by facilitating the electrification of the electric transport refrigeration unit, the environmental resistance of the transport refrigeration vehicle can be improved. The predetermined reference voltage value is set based on the user's usage. For example, it is an intermediate value or a value in an intermediate range between the voltage value that the first external power source can supply and the voltage value that the second external power source can supply. For example, if the voltage value that the first external power source can supply ranges from 12V to 60V and the voltage value that the second external power source can supply ranges from 200V to 800V, the reference voltage value ranges from 61V to 199V.

[0092] In the control system for an electric transport refrigeration unit according to the second aspect of the present disclosure, in the first aspect, when the first external power source and a generator (10) that supplies power to the electric transport refrigeration unit are connected to the electric transport refrigeration unit, the first external power source can be driven in parallel with the generator and is applied as an auxiliary power source corresponding to the load of the electric transport refrigeration unit.

[0093] According to the control system for an electric transport refrigeration unit according to the present disclosure, when the first external power supply is driven in parallel with the generator that supplies power to the electric transport refrigeration unit, it is used as an auxiliary power supply corresponding to the load of the electric transport refrigeration unit. In this case, the generator serves as the main power supply for driving the electric transport refrigeration unit, and the first external power supply serves as the auxiliary power supply for driving the electric transport refrigeration unit. This makes it possible to stabilize the power supply to the electric transport refrigeration unit and the driving capacity of the electric transport refrigeration unit.

[0094] A control system for an electric transport refrigeration unit according to a third aspect of the present disclosure is, in the first aspect, when the first external power source, a generator (10) that supplies power to the electric transport refrigeration unit, and a chargeable and dischargeable power storage unit (103) that supplies power to the electric transport refrigeration unit are connected to the electric transport refrigeration unit, the first external power source can be driven in parallel with the generator and is used as a power source for charging the power storage unit.

[0095] According to the control system for the electric transport refrigeration unit disclosed herein, the first external power supply is used as a power supply for charging the power storage unit when driven in parallel with the generator that supplies power to the electric transport refrigeration unit. In this case, the generator serves as the main power supply for driving the electric transport refrigeration unit, and the first external power supply serves as a power supply for charging the battery. This makes it possible to charge the power storage unit while maintaining the power supply to the electric transport refrigeration unit and the driving capacity of the electric transport refrigeration unit, thereby improving power efficiency when driving the electric transport refrigeration unit.

[0096] The control system for an electric transport refrigeration unit according to a fourth aspect of the present disclosure is, in the first aspect, when the second external power source, a generator (10) that supplies power to the electric transport refrigeration unit, and a chargeable and dischargeable power storage unit (103) that supplies power to the electric transport refrigeration unit are connected to the electric transport refrigeration unit, the second external power source can be driven in parallel with the generator and is used as a main power source corresponding to the load of the electric transport refrigeration unit.

[0097] According to the control system for the electric transport refrigeration unit disclosed herein, when the second external power supply is driven in parallel with the generator that supplies power to the electric transport refrigeration unit, it is used as the main power supply corresponding to the load of the electric transport refrigeration unit. In this case, the generator serves as an auxiliary power supply for driving the electric transport refrigeration unit, and the second external power supply serves as the main power supply for driving the electric transport refrigeration unit. This makes it possible to stabilize the power supply to the electric transport refrigeration unit and the driving capacity of the electric transport refrigeration unit.

[0098] The control system for an electric transport refrigeration unit according to a fifth aspect of the present disclosure, in either the first or fourth aspect, further includes an adjustment unit (40) that adjusts each of the powers supplied from the second external power source or the commercial power source when a commercial power source (104) that is capable of supplying power in parallel with the second external power source and supplies power to the electric transport refrigeration unit is connected to the electric transport refrigeration unit, and the commercial power source is applied as a power source that supplies power to the electric transport refrigeration unit in response to the power supplied from the second external power source to the electric transport refrigeration unit.

[0099] According to the control system for the electric transport refrigeration unit according to the present disclosure, the commercial power source is used as a power source that supplies power to the electric transport refrigeration unit in response to the power supplied from the second external power source to the electric transport refrigeration unit. As a result, when it is not preferable to drive the transport refrigeration unit with power from the second external power source at a stop location of the transport refrigeration vehicle, such as a distribution center, the electric transport refrigeration unit can be stably driven by supplying power from the commercial power source to the electric transport refrigeration unit. Here, the commercial power source is a power source that can be externally connected to the electric transport refrigeration unit installed at a stop location of the transport refrigeration vehicle, such as a distribution center.

[0100] The control system for an electric transport refrigeration unit according to a sixth aspect of the present disclosure, in the first aspect, when the first external power source and a chargeable and dischargeable power storage unit (103) that supplies power to the electric transport refrigeration unit are connected to the electric transport refrigeration unit, further includes a third interface (301C) corresponding to the first external power source connected in parallel to the first interface, and a power storage auxiliary unit (302) that limits the current flowing to the power storage unit when the charging rate (SOC: State Of Charge) of the power storage unit is lower than a preset reference value, and the controller controls to drive the third interface instead of the first interface when the charging rate of the power storage unit is lower than a preset reference value.

[0101] According to the control system for the electric transport refrigeration unit disclosed herein, when the first external power source is connected to the electric transport refrigeration unit and the charging rate of the power storage unit is lower than a preset reference value, the control system controls the third interface to be driven instead of the first interface. Furthermore, the auxiliary power storage unit limits the current flowing to the power storage unit when the charging rate of the power storage unit is low. When the charging rate of the power storage unit is low, there is a risk that a large current, such as an inrush current, will suddenly flow to the power storage unit if the power storage unit is charged using power supplied from the external power source. Therefore, when the charging rate of the power storage unit is low, the power storage unit is charged using power supplied from the auxiliary power storage unit to increase the charging rate. This prevents damage to the power storage unit and enables the power storage unit to be continuously charged.

[0102] A seventh aspect of the present disclosure relates to a control system for an electric transport refrigeration unit according to the sixth aspect, wherein the auxiliary power storage unit includes a first positive electric wire and a second negative electric wire, and the first electric wire and the second electric wire are separated from other electric wires included in the electric transport refrigeration unit.

[0103] According to the control system for an electric transport refrigeration unit of the present disclosure, the first positive electric wire and the second negative electric wire of the auxiliary power storage unit are electric wires separated from other electric wires. Here, the other electric wires are specifically power supply lines. This prevents the first and second electric wires from interfering electrically with the other electric wires through which high power flows. Furthermore, it is possible to improve the EMC (Electromagnetic Compatibility) of the control system for the electric transport refrigeration unit and the circuits of this control system.

[0104] In the control system for an electric transport refrigeration unit according to an eighth aspect of the present disclosure, in any one of the first, second, third, sixth or seventh aspects, the voltage value of the power supplied from the first external power source is 12V to 60V.

[0105] In the control system for an electric transport refrigeration unit according to a ninth aspect of the present disclosure, in any one of the first, fourth or fifth aspects, the voltage value of the power supplied from the second external power source is 200V to 800V.

[0106] An electric transport refrigeration unit according to a tenth aspect of the present disclosure includes an inverter, a converter, an electric compressor, and a control system of the electric transport refrigeration unit according to any one of the first to ninth aspects.

[0107] A control method for a control system of an electric transport refrigeration unit according to an eleventh aspect of the present disclosure is a control method for a control system of an electric transport refrigeration unit that supplies power from an external power source, and includes the steps of driving either a first interface corresponding to a first external power source that supplies a voltage lower than a predetermined reference voltage value, or a second interface corresponding to a second external power source that supplies a voltage higher than a predetermined reference voltage value, and controlling whether the first interface or the second interface is to be driven depending on whether the first external power source or the second external power source is connected to the electric transport refrigeration unit.

[0108] A control program for a control system of an electric transport refrigeration unit according to a twelfth aspect of the present disclosure is a control program for a control system of an electric transport refrigeration unit that supplies power from an external power source, and causes a computer to execute a process of driving either a first interface corresponding to a first external power source that supplies a voltage lower than a predetermined reference voltage value, or a second interface corresponding to a second external power source that supplies a voltage higher than a predetermined reference voltage value, and a process of controlling the driving of either the first interface or the second interface depending on whether the first external power source or the second external power source is connected to the electric transport refrigeration unit. [Explanation of symbols]

[0109] 1. Refrigerated transport vehicles 2 Tractor 3. Storage 4 Electric transport refrigerator 5. Compressor 6 Condensing Unit 7 Evaporator unit 9 Engine 10. Alternator 30 Supply section 40 Adjustment part 50 Control unit (controller) 51 CPU 52 Auxiliary storage 53 Main memory 54 Communication Interface 55 Input / output section 56 Bus 57 Reception 58 Judgment section 59 Command Department 101 Low voltage external power supply (first external power supply) 102 High voltage external power supply (second external power supply) 103 Battery (storage unit) 104 Commercial power supply 301A 1st Power Relay (1st Interface) 301B Second Power Relay (Second Interface) 301C 3rd Power Relay (3rd Interface) 302 Battery charger (power storage auxiliary unit) 303 Contactor 401 DC / DC Boost Converter 402 Inverter 403 AC / DC Converter 404 DC / DC Step-Down Converter 501 Low Voltage Load 501A Control Board 502,503 PR drive relay

Claims

1. Applicable to electric transport refrigerators comprising an inverter, a converter, and an electric compressor, A first interface corresponding to a first external power supply that supplies a voltage lower than a predetermined reference voltage value, A second interface corresponding to a second external power supply that supplies a voltage higher than a predetermined reference voltage value, A controller that controls which of the first or second external power supply is driven depending on whether the first or second external power supply is connected to the electric transport refrigerator, and Equipped with, When the first external power supply and a rechargeable and dischargeable energy storage unit that supplies power to the electric transport refrigerator are connected to the electric transport refrigerator, A third interface corresponding to the first external power supply, connected in parallel with the first interface, When the State of Charge (SOC) of the energy storage unit is lower than a preset reference value, an energy storage auxiliary unit limits the current flowing to the energy storage unit. Furthermore, The controller is a control system for an electric transport refrigerator that controls the third interface to drive instead of the first interface when the charge level of the energy storage unit is lower than a preset reference value.

2. When the first external power source and the generator that supplies power to the electric transport refrigerator are connected to the electric transport refrigerator, The control system for an electric transport refrigerator according to claim 1, wherein the first external power supply can be driven in parallel with the generator and is applied as an auxiliary power supply corresponding to the load of the electric transport refrigerator.

3. When the aforementioned first external power supply, a generator that supplies power to the electric transport refrigerator, and a rechargeable and dischargeable energy storage unit that supplies power to the electric transport refrigerator are connected to the electric transport refrigerator, The control system for an electric transport refrigerator according to claim 1, wherein the first external power supply is capable of being driven in parallel with the generator and is applied as a power supply for charging the energy storage unit.

4. When the second external power supply, the generator that supplies power to the electric transport refrigerator, and the rechargeable and dischargeable energy storage unit that supplies power to the electric transport refrigerator are connected to the electric transport refrigerator, The control system for an electric transport refrigerator according to claim 1, wherein the second external power supply can be driven in parallel with the generator and is applied as a main power supply corresponding to the load of the electric transport refrigerator.

5. In a case where power can be supplied in parallel with the second external power supply, and a commercial power supply that supplies power to the electric transport refrigerator is connected to the electric transport refrigerator, The system further includes an adjustment unit that adjusts each of the power supplied from the second external power supply or the commercial power supply, The control system for an electric transport refrigerator according to claim 1, wherein the commercial power supply is applied as a power supply that supplies power to the electric transport refrigerator in accordance with the power supplied to the electric transport refrigerator from the second external power supply.

6. The aforementioned energy storage auxiliary unit includes a first positive electrode wire and a second negative electrode wire. The control system for an electric transport refrigerator according to claim 1, wherein the first and second electric wires are separated from other electric wires provided by the electric transport refrigerator.

7. The control system for an electric transport refrigerator according to claim 1, wherein the voltage value of the power supplied from the first external power source is 12V to 60V.

8. The control system for an electric transport refrigerator according to claim 1, wherein the voltage value of the power supplied from the second external power source is 200V to 800V.

9. Inverter and Converter and, Electric compressor and, The control system for an electric transport refrigerator according to claim 1 and An electric transport refrigerator equipped with the following features.

10. A control method for a control system of an electric transport refrigerator that is powered by an external power source, A step of driving either a first interface corresponding to a first external power supply that supplies a voltage lower than a predetermined reference voltage value, or a second interface corresponding to a second external power supply that supplies a voltage higher than a predetermined reference voltage value, A step of controlling which of the first external power supply or the second external power supply is connected to the electric transport refrigerator, and which of the first interface or the second interface is driven. It has, When the first external power supply and a rechargeable and dischargeable energy storage unit that supplies power to the electric transport refrigerator are connected to the electric transport refrigerator, A third interface corresponding to the first external power supply, connected in parallel with the first interface, When the State of Charge (SOC) of the energy storage unit is lower than a preset reference value, an energy storage auxiliary unit limits the current flowing to the energy storage unit. Furthermore, A control method for a control system of an electric transport refrigerator, comprising the step of controlling the system to drive the third interface instead of the first interface when the charge level of the energy storage unit is lower than a preset reference value.

11. A control program for a control system of an electric transport refrigerator that is powered by an external power source, A process to drive either a first interface corresponding to a first external power supply that supplies a voltage lower than a predetermined reference voltage value, or a second interface corresponding to a second external power supply that supplies a voltage higher than a predetermined reference voltage value, A process to control which of the first or second interface is driven depending on whether the first or second external power supply is connected to the electric transport refrigerator, When the first external power supply and a rechargeable and dischargeable energy storage unit that supplies power to the electric transport refrigerator are connected to the electric transport refrigerator, A third interface corresponding to the first external power supply, connected in parallel with the first interface, When the State of Charge (SOC) of the energy storage unit is lower than a preset reference value, an energy storage auxiliary unit limits the current flowing to the energy storage unit. Furthermore, When the charge level of the energy storage unit is lower than a preset reference value, a process is performed to control the operation of the third interface instead of the first interface, A control program for the control system of an electric transport refrigeration unit, which is used to run on a computer.

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