Electric control box applied to refrigerating system

Abstract

The invention discloses an electric control box applied to a refrigerating system, and belongs to the technical field of power electronics. The PFC circuit is connected with the filtering module; the fan control module is connected with the PFC circuit and a fan in the refrigerating system and is used for controlling the rotating speed of the fan; the compressor control module is connected with the PFC circuit and a compressor in the refrigerating system and used for controlling the compressor through the first IPM module; the water pump control module is connected with the PFC circuit and a water pump in the refrigerating system and used for controlling the water pump through the second IPM module; the central control module is connected with the PFC circuit, the fan control module, the compressor control module and the water pump control module and used for providing driving signals for the PFC circuit, the fan control module, the compressor control module and the water pump control module. According to the structure, the space occupation, the manufacturing cost and the wiring complexity of the electric control box can be remarkably reduced.

Description

Technical Field

[0001] The invention relates to the technical field of power electronics, and in particular to an electric control box applied to a refrigeration system. Background Art

[0002] In the prior art, the integration of the internal components of the electric control box used to control the refrigeration system is not high. For example, the internal filter circuit, PFC (Power Factor Correction) circuit, fan, compressor, water pump and other control circuits are all controlled separately by different control modules, which results in too many circuit boards in the electric control box, complicated wiring, not smooth routing, too many EMI (Electromagnetic Interference) introduction measures, which leads to a large space occupation and high cost of the electric control box. In addition, the fan speed regulation in the electric control box is controlled by a solid-state relay, and the use of solid-state relays further increases the production cost of the electric control box. At present, there is no more effective solution to this technical problem.

[0003] It can be seen that how to reduce the space occupied by the electric control box, the production cost and the wiring complexity is a technical problem that needs to be solved urgently by technical personnel in this field. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide an electric control box for use in a refrigeration system to solve the technical problems of the electric control box in the prior art, such as large space occupation, high cost and complicated wiring. The specific solution is as follows:

[0005] In order to solve the above technical problems, the present invention provides an electric control box applied to a refrigeration system, comprising:

[0006] Filter module, used to filter out EMI signals in AC power;

[0007] A PFC circuit, connected to the filter module, for reducing harmonic current in the AC power and improving the power factor of the AC power;

[0008] A fan control module, connected to the PFC circuit and the fan in the refrigeration system, for controlling the speed of the fan;

[0009] a compressor control module connected to the PFC circuit and the compressor in the refrigeration system, and configured to control the compressor through a first IPM module;

[0010] a water pump control module connected to the PFC circuit and the water pump in the refrigeration system, and configured to control the water pump through a second IPM module;

[0011] The central control module is connected to the PFC circuit, the fan control module, the compressor control module and the water pump control module, and is used to provide driving signals to the PFC circuit, the fan control module, the compressor control module and the water pump control module respectively.

[0012] Preferably, the filtering module comprises: a fuse, a first varistor, a second varistor, a gas discharge tube, a first X capacitor, a second X capacitor, a first common mode inductor and a second common mode inductor;

[0013] Wherein, two ends of the AC voltage source are respectively connected to the first end of the fuse and the first end of the first varistor, the second end of the fuse is respectively connected to the first end of the first X capacitor, the first end of the second varistor and the first end of the first common-mode inductor, the second end of the first varistor and the second end of the second varistor are both connected to the first end of the gas discharge tube, the second end of the gas discharge tube is grounded, the second end of the first X capacitor is connected to the second end of the first common-mode inductor, the third end of the first common-mode inductor is respectively connected to the first end of the second X capacitor and the first end of the second common-mode inductor, and the fourth end of the first common-mode inductor is respectively connected to the second end of the second X capacitor and the second end of the second common-mode inductor;

[0014] Correspondingly, the third end of the second common-mode inductor and the fourth end of the common-mode inductor are output ends of the filtering module respectively.

[0015] Preferably, the coils of the first common-mode inductor and the second common-mode inductor are both in the form of flat wires, the annular magnetic cores of the first common-mode inductor and the second common-mode inductor are both flatly arranged on a circuit board, and a thermally conductive silicone pad is attached to one side of the first common-mode inductor and the second common-mode inductor close to the circuit board.

[0016] Preferably, the fan control module comprises: a first resistor, a thyristor and a first controllable switch;

[0017] Among them, the first end of the first resistor is respectively connected to the first end of the first controllable switch and the output end of the filter module, the second end of the first resistor is respectively connected to the second end of the first controllable switch and the negative electrode of the thyristor, and the positive electrode of the thyristor is connected to the AC fan in the refrigeration system; the control end of the first controllable switch and the control end of the thyristor are both used to receive the drive signal sent by the central control module.

[0018] Preferably, the PFC circuit comprises: a rectifier bridge for rectifying the alternating current, a second controllable switch, a diode and a second resistor;

[0019] Among them, the first end of the inductor in the refrigeration system is connected to the output end of the rectifier, the second end of the inductor is respectively connected to the positive electrode of the diode and the first end of the second controllable switch, the second end of the second controllable switch is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the control end of the second controllable switch is used to receive the drive signal sent by the central control module.

[0020] Preferably, the compressor control module comprises: a first capacitor, a third controllable switch, a fourth controllable switch, a fifth controllable switch, a sixth controllable switch, a seventh controllable switch, an eighth controllable switch, a third resistor, a fourth resistor and a fifth resistor;

[0021] Wherein, the first end of the third controllable switch, the first end of the fourth controllable switch and the first end of the fifth controllable switch are all connected to the DC bus, the output end of the PFC circuit is connected to the DC bus, the first end of the first capacitor is connected to the DC bus, the second end of the first capacitor is grounded, the second end of the third controllable switch is connected to the first end of the sixth controllable switch, the second end of the fourth controllable switch is connected to the first end of the seventh controllable switch, the second end of the fifth controllable switch is connected to the first end of the eighth controllable switch, the second end of the sixth controllable switch is connected to the first end of the third resistor, the second end of the seventh ... and the second end of the sixth controllable switch is connected to the first end of the third resistor. The first end of the eighth controllable switch is connected to the first end of the fourth resistor, the second end of the eighth controllable switch is connected to the first end of the fifth resistor, the second end of the third resistor, the second end of the fourth resistor and the second end of the fifth resistor are all grounded; the control end of the third controllable switch, the control end of the fourth controllable switch, the control end of the fifth controllable switch, the control end of the sixth controllable switch, the control end of the seventh controllable switch and the control end of the eighth controllable switch are all used to receive the driving signal sent by the central control module, and the second end of the third controllable switch, the second end of the fourth controllable switch and the second end of the fifth controllable switch are respectively connected to the compressor.

[0022] Preferably, the central control module includes:

[0023] A first control circuit board, used for providing a driving signal to the PFC circuit, the fan control module, the compressor control module and the water pump control module;

[0024] The second control circuit board is used to control the first control circuit board, provide a human-computer interaction interface, and display input data and output data.

[0025] Preferably, the first control circuit board comprises:

[0026] First MCU;

[0027] An RS485 interface provided on the first MUC;

[0028] A first auxiliary power supply connected to the first MCU and used to provide a source of electrical energy;

[0029] A temperature sensor, connected to the first MCU, for detecting the temperature value of each device;

[0030] A voltage sensor, connected to the first MCU, for detecting the voltage value of each device;

[0031] A current sensor, connected to the first MCU, for detecting the current value of each device;

[0032] The fan module is connected to the first MCU via an optical coupler and is used for dissipating heat for the first MCU.

[0033] Preferably, the second control circuit board comprises:

[0034] Second MCU;

[0035] A second auxiliary power supply connected to the second MCU and used to provide a source of electrical energy;

[0036] A drive control module connected to the second MCU and used for performing signal conversion;

[0037] A CAN interface provided on the second MCU;

[0038] An RS485 interface provided on the second MCU;

[0039] An analog input module and an analog output module are provided on the second MCU;

[0040] A digital quantity input module and a digital quantity output module are arranged on the second MCU;

[0041] An electromagnetic expansion valve connected to the second MCU and used for throttling and reducing the pressure of the refrigeration system.

[0042] Preferably, the second control circuit board is stacked on the first control circuit board via support columns.

[0043] Beneficial effect: In the electric control box applied to the refrigeration system provided in the present invention, a filter module, a PFC circuit, a fan control module, a compressor control module, a water pump control module and a central control module are provided, wherein the PFC circuit, the fan control module, the compressor control module and the water pump control module are all controlled by the central control module, thus making the integration of the PFC circuit, the fan control module, the compressor control module, the water pump control module and the central control module higher, and the filter module can also filter out the EMI signal in the alternating current, thus reducing the number of EMI measures introduced into the electric control box, and significantly reducing the space occupied, construction cost and wiring complexity of the electric control box. At the same time, the speed of the fan in the refrigeration system is controlled by the central control module, and there is no need to set a solid-state relay in the electric control box, thus further reducing the construction cost of the electric control box. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0045] Figure 1 A structural diagram of an electric control box for a refrigeration system provided by an embodiment of the present invention;

[0046] Figure 2 The working principle diagram of the electric control box when the fan in the refrigeration system is set as an AC fan;

[0047] Figure 3 The working principle diagram of the electric control box when the fan in the refrigeration system is set as a DC fan;

[0048] Figure 4 A structural diagram of another electric control box for a refrigeration system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] See also Figure 1 , Figure 1 The present invention provides a structural diagram of an electric control box applied to a refrigeration system, the electric control box comprising:

[0051] The filter module 11 is used to filter out EMI signals in the alternating current;

[0052] The PFC circuit 12 is connected to the filter module 11 and is used to reduce the harmonic current in the AC power and improve the power factor of the AC power;

[0053] A fan control module 13 is connected to the PFC circuit 12 and the fan in the refrigeration system, and is used to control the speed of the fan;

[0054] A compressor control module 14, connected to the PFC circuit 12 and the compressor in the refrigeration system, for controlling the compressor through the first IPM module;

[0055] A water pump control module 15, connected to the PFC circuit 12 and the water pump in the refrigeration system, for controlling the water pump through the second IPM module;

[0056] The central control module 16 is connected to the PFC circuit 12, the fan control module 13, the compressor control module 14 and the water pump control module 15, and is used to provide driving signals to the PFC circuit 12, the fan control module 13, the compressor control module 14 and the water pump control module 15 respectively.

[0057] In this embodiment, an electric control box for a refrigeration system is provided, in which a filter module 11, a PFC circuit 12, a fan control module 13, a compressor control module 14, a water pump control module 15 and a central control module 16 are arranged.

[0058] Among them, the filter module 11 is used to filter out the EMI signal in the AC power, which can meet the EMI test requirements and EMS (Electromagnetic Susceptibility) test requirements of the refrigeration system, and play a role in resisting common mode interference and differential mode interference of the whole machine. In addition, after filtering out the EMI signal in the AC power, the filter module 11 will use the AC power after filtering out the EMI signal to power the PFC circuit 12, the fan control module 13, the compressor control module 14, the water pump control module 15 and the central control module 16 connected to its rear end, which is equivalent to setting the filter module 11 at the front end of the AC power, thereby further reducing the number of EMI measures introduced in the electric control box and reducing the number of wiring in the electric control box.

[0059] The PFC circuit 12 is used to solve the current harmonics in the AC power and improve the power factor of the AC power, so that the THD (Total Harmonic Distortion) of the whole machine can meet the requirements of the refrigeration system. In practical applications, the central control module 16 mainly corrects the power factor of the PFC circuit through the CCM (Continuous Conduction Mode) algorithm. It should be noted that the AC power described in this application can be either three-phase AC power or single-phase AC power, which is not specifically limited here.

[0060] The fan control module 13, the compressor control module 14 and the water pump control module 15 are three functional modules used for refrigeration in the refrigeration system. The fan control module 13 is mainly used to control the fan of the refrigeration system, the compressor control module 14 is mainly used to control the compressor in the refrigeration system, and the water pump control module 15 is mainly used to control the water pump in the refrigeration system.

[0061] The central control module 16 is connected to the PFC circuit 12, the fan control module 13, the compressor control module 14 and the water pump control module 15, and is used to provide driving signals to the PFC circuit 12, the fan control module 13, the compressor control module 14 and the water pump control module 15. That is, in the present application, one central control module 16 can control the PFC circuit 12, the fan control module 13, the compressor control module 14 and the water pump control module 15 at the same time, which is equivalent to integrating several functional modules on a circuit board, which can not only reduce the cost of the electric control box, but also make the wiring in the electric control box smoother and reduce the wiring complexity in the electric control box.

[0062] Moreover, in the present application, the speed of the fan in the refrigeration system is controlled by the central control module 16, and there is no need to set a solid-state relay in the electrical control box. This can further reduce the number of components set in the electrical control box and significantly reduce the cost of the electrical control box and the space occupied.

[0063] It should be noted that in actual applications, the central control module 16 is usually integrated by a PLC (Programmable Logic Controller) circuit and controlled by an MCU (Micro Controller Unit). When the electric control box starts running, the AC power will first be filtered by the filter module 11 and harmonically modulated by the PFC circuit 12. Then, the rectifier module will rectify the AC power and supply power to the compressor control module 14, the water pump control module 15 and the central control module 16. During this process, the central control module 16 will send corresponding drive signals to the PFC circuit 12, the compressor control module 14 and the water pump control module 15, and control the PFC circuit 12, the compressor control module 14 and the water pump control module 15 respectively.

[0064] The fan in the refrigeration system can be either an AC fan or a DC fan. When the fan in the refrigeration system is an AC fan, the fan control module 13 is arranged at the front end of the PFC circuit 12, and the AC fan is powered by AC power, and the fan control module 13 is driven and controlled by the central control module 16. When the fan in the refrigeration system is a DC fan, the fan control module 13 is arranged at the back end of the PFC circuit 12, and the DC fan is powered by DC power after the AC power is rectified by the rectifier module, and the fan control module 13 is driven and controlled by the central control module 16. For details, please refer to Figure 2 and Figure 3 , Figure 2 The working principle diagram of the electric control box when the fan in the refrigeration system is set as an AC fan; Figure 3 This is the working principle diagram of the electric control box when the fan in the refrigeration system is set as a DC fan.

[0065] In the electric control box applied to the refrigeration system provided in this embodiment, a filter module, a PFC circuit, a fan control module, a compressor control module, a water pump control module and a central control module are provided, wherein the PFC circuit, the fan control module, the compressor control module and the water pump control module are all controlled by the central control module, thus making the integration of the PFC circuit, the fan control module, the compressor control module, the water pump control module and the central control module higher, and the filter module can also filter out the EMI signal in the AC power, thus reducing the number of EMI measures introduced in the electric control box, and significantly reducing the space occupied, construction cost and wiring complexity of the electric control box. At the same time, the speed of the fan in the refrigeration system is controlled by the central control module, and there is no need to set a solid-state relay in the electric control box, thus further reducing the construction cost of the electric control box.

[0066] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Figure 4 , Figure 4 A structural diagram of an electric control box applied to a refrigeration system provided by an embodiment of the present invention. As a preferred implementation, the filter module 11 includes: a fuse FU, a first varistor VDR1, a second varistor VDR2, a gas discharge tube GDT, a first X capacitor XC1, a second X capacitor XC2, a first common mode inductor L1 and a second common mode inductor L2;

[0067] Wherein, two ends of the AC voltage source are respectively connected to the first end of the fuse FU and the first end of the first varistor VDR1, the second end of the fuse FU is respectively connected to the first end of the first X capacitor XC1, the first end of the second varistor VDR2 and the first end of the first common-mode inductor L1, the second end of the first varistor VDR1 and the second end of the second varistor VDR2 are both connected to the first end of the gas discharge tube GDT, the second end of the gas discharge tube GDT is grounded, the second end of the first X capacitor XC1 is connected to the second end of the first common-mode inductor L1, the third end of the first common-mode inductor L1 is respectively connected to the first end of the second X capacitor XC2 and the first end of the second common-mode inductor L2, and the fourth end of the first common-mode inductor L1 is respectively connected to the second end of the second X capacitor XC2 and the second end of the second common-mode inductor L2;

[0068] Correspondingly, the third end of the second common-mode inductor L2 and the fourth end of the common-mode inductor are output ends of the filter module 11 respectively.

[0069] In this embodiment, the structure of the filter module 11 is specifically described. The filter module 11 is provided with a fuse FU, a gas discharge tube GDT (Gas Discharge Tube, GDT), a varistor, an X capacitor and a common mode inductor.

[0070] Among them, the function of the fuse FU is to protect the devices in the circuit from damage by overcurrent; the function of the gas discharge tube GDT is to provide overvoltage protection and discharge lightning instantaneous overcurrent; the first varistor VDR1 and the second varistor VDR2 can quickly absorb the excess current in the circuit under the instantaneous overvoltage event and protect the subsequent circuit; the first X capacitor XC1 and the second X capacitor XC2 can suppress differential mode interference and electromagnetic interference in the circuit; the first common mode inductor L1 and the second common mode inductor L2 can suppress the common mode noise in the circuit and increase the stability of the circuit.

[0071] As a preferred embodiment, the coils of the first common-mode inductor L1 and the second common-mode inductor L2 are both in the form of flat wires, the annular magnetic cores of the first common-mode inductor L1 and the second common-mode inductor L2 are both flatly arranged on the circuit board, and a thermal conductive silicone pad is attached to one side of the first common-mode inductor L1 and the second common-mode inductor L2 close to the circuit board.

[0072] Due to the high degree of integration of the circuit board, the heat dissipation performance of the integrated circuit board will be deteriorated. If the annular magnetic cores of the first common mode inductor L1 and the second common mode inductor L2 are vertically arranged on the circuit board according to the usual practice, the first common mode inductor L1 and the second common mode inductor L2 can only be cooled by natural heat dissipation of the air, which will greatly affect the heat dissipation performance of the first common mode inductor L1 and the second common mode inductor L2.

[0073] In order to improve the heat dissipation capacity of the first common-mode inductor L1 and the second common-mode inductor L2, the coils of the first common-mode inductor L1 and the second common-mode inductor L2 can be set to flat wire form, and the annular magnetic cores of the first common-mode inductor L1 and the second common-mode inductor L2 can be laid flat on the circuit board. Then, the heat dissipated by the first common-mode inductor L1 and the second common-mode inductor L2 can be dissipated through the radiator through the thermal conductive silicone pad laid under the first common-mode inductor L1 and the second common-mode inductor L2, thereby increasing the heat dissipation capacity of the first common-mode inductor L1 and the second common-mode inductor L2.

[0074] Obviously, the technical solution provided in this embodiment can improve the heat dissipation efficiency of the first common-mode inductor and the second common-mode inductor.

[0075] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Figure 4 , Figure 4 A structural diagram of an electric control box applied to a refrigeration system provided by an embodiment of the present invention. As a preferred implementation, the fan control module 13 includes: an AC fan arranged in the refrigeration system, a first resistor R1, a thyristor VT and a first controllable switch Q1;

[0076] Among them, the first end of the first resistor R1 is respectively connected to the first end of the first controllable switch Q1 and the output end of the filter module, the second end of the first resistor R1 is respectively connected to the second end of the first controllable switch Q1 and the negative electrode of the thyristor VT, and the positive electrode of the thyristor VT is connected to the AC fan; the control end of the first controllable switch Q1 and the control end of the thyristor VT are both used to receive the drive signal sent by the central control module.

[0077] When the fan in the refrigeration system is an AC fan, a first resistor R1, a thyristor VT and a first controllable switch Q1 can be set in the fan control module 13; wherein the thyristor VT is used to control the speed of the AC fan. The central control module 16 controls the speed of the AC fan by chopping technology. When the AC fan is running at full speed, the on-off cycle of the control signal output by the thyristor VT by the central control module 16 is 20ms, and the positive and negative half cycles are 10ms each. When the central control module requires a 50% speed, the central control module needs to turn on the thyristor VT at 5ms of the positive and negative half cycles.

[0078] Obviously, through the technical solution provided in this embodiment, the AC fan in the refrigeration system can be controlled.

[0079] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Figure 4 , Figure 4 A structural diagram of an electric control box applied to a refrigeration system provided by an embodiment of the present invention. As a preferred embodiment, the PFC circuit 12 includes: a rectifier bridge 120 for rectifying AC power, a second controllable switch Q2, a diode D1 and a second resistor R2;

[0080] Among them, the first end of the inductor in the refrigeration system is connected to the output end of the rectifier bridge 120, the second end of the inductor is respectively connected to the positive electrode of the diode D1 and the first end of the second controllable switch Q2, the second end of the second controllable switch Q2 is connected to the first end of the second resistor R2, the second end of the second resistor R2 is grounded, and the control end of the second controllable switch Q2 is used to receive the driving signal sent by the central control module.

[0081] In this embodiment, the internal structure of the PFC circuit 12 is specifically described. The PFC circuit 12 is provided with a rectifier bridge 120, a second controllable switch Q2, a diode D1 and a second resistor R2. The rectifier bridge 120 is composed of diodes D01, D02, D03 and D04. The PFC circuit 12 mainly drives and controls the second controllable switch Q2 through a driving signal sent by a central control module to achieve the purpose of reducing the harmonic current of the alternating current and improving the power factor of the alternating current.

[0082] Specifically, the central control module may use an average current control algorithm (Average Current Control), a peak current control algorithm (Peak Current Control) or a double loop control algorithm (Double Loop Control Algorithm) to control the PFC circuit, which will not be described in detail here.

[0083] Obviously, through the technical solution provided in this embodiment, the PFC circuit can be used to reduce the harmonic current in the AC power and improve the power factor of the AC power.

[0084] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Figure 4 , Figure 4 A structural diagram of an electric control box applied to a refrigeration system provided by an embodiment of the present invention. As a preferred implementation, the compressor control module 14 includes: a first capacitor C1, a third controllable switch Q3, a fourth controllable switch Q4, a fifth controllable switch Q5, a sixth controllable switch Q6, a seventh controllable switch Q7, an eighth controllable switch Q8, a third resistor R3, a fourth resistor R4 and a fifth resistor R5;

[0085] Among them, the first end of the third controllable switch Q3, the first end of the fourth controllable switch Q4 and the first end of the fifth controllable switch Q5 are all connected to the DC bus, the output end of the PFC circuit 12 is connected to the DC bus, the first end of the first capacitor C1 is connected to the DC bus, the second end of the first capacitor C1 is grounded, the second end of the third controllable switch Q3 is connected to the first end of the sixth controllable switch Q6, the second end of the fourth controllable switch Q4 is connected to the first end of the seventh controllable switch Q7, the second end of the fifth controllable switch Q5 is connected to the first end of the eighth controllable switch Q8, the second end of the sixth controllable switch Q6 is connected to the first end of the third resistor R3, the second end of the seventh controllable switch Q7 is connected to the first end of the eighth controllable switch Q8, and the second end of the sixth controllable switch Q6 is connected to the first end of the third resistor R3 and the second end of the seventh controllable switch Q7. The first end of the eighth controllable switch Q8 is connected to the first end of the fourth resistor R4, the second end of the eighth controllable switch Q8 is connected to the first end of the fifth resistor R5, the second end of the third resistor R3, the second end of the fourth resistor R4 and the second end of the fifth resistor R5 are all grounded; the control end of the third controllable switch Q3, the control end of the fourth controllable switch Q4, the control end of the fifth controllable switch Q5, the control end of the sixth controllable switch Q6, the control end of the seventh controllable switch Q7 and the control end of the eighth controllable switch Q8 are all used to receive the driving signal sent by the central control module, and the second end of the third controllable switch Q3, the second end of the fourth controllable switch Q4 and the second end of the fifth controllable switch Q5 are respectively connected to the compressor.

[0086] In this embodiment, the structure of the compressor control module 14 is specifically described. Figure 4In the circuit diagram shown, +400V is a DC bus, and the third controllable switch Q3, the fourth controllable switch Q4, the fifth controllable switch Q5, the sixth controllable switch Q6, the seventh controllable switch Q7 and the eighth controllable switch Q8 form an IPM module. The output voltage of the PFC circuit 12 is boosted by the DC bus to supply power to the compressor. At the same time, the central control module will send corresponding drive signals to the control ends of the third controllable switch Q3, the fourth controllable switch Q4, the fifth controllable switch Q5, the sixth controllable switch Q6, the seventh controllable switch Q7 and the eighth controllable switch Q8 based on the FOC (Field Oriented Control) algorithm to perform variable frequency control on the compressor.

[0087] Based on the same principle, Figure 4 In the embodiment, the ninth controllable switch Q9, the tenth controllable switch Q10, the eleventh controllable switch Q11, the twelfth controllable switch Q12, the thirteenth controllable switch Q13 and the fourteenth controllable switch Q14 form a second IPM module. The output voltage of the PFC circuit 12 is boosted by the DC bus to supply power to the water pump. At the same time, the central control module will send corresponding drive signals to the control ends of the ninth controllable switch Q9, the tenth controllable switch Q10, the eleventh controllable switch Q11, the twelfth controllable switch Q12, the thirteenth controllable switch Q13 and the fourteenth controllable switch Q14 based on the FOC algorithm to perform variable frequency control on the water pump.

[0088] Obviously, through the technical solution provided in this embodiment, the central control module can achieve the purpose of controlling the compressor control module and the water pump control module.

[0089] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Figure 4 , Figure 4 This is a structural diagram of an electric control box applied to a refrigeration system provided by an embodiment of the present invention. As a preferred implementation, the central control module 16 includes:

[0090] A first control circuit board 161, used to provide a driving signal to the PFC circuit, the fan control module, the compressor control module and the water pump control module;

[0091] The second control circuit board 162 is used to control the first control circuit board 161, provide a human-computer interaction interface, and display input data and output data.

[0092] In this embodiment, in order to make the division of labor of each functional module in the central control module 16 clearer and improve the working performance of the central control module 16, a first control circuit board 161 and a second control circuit board 162 independent of each other are set in the central control module 16.

[0093] Among them, the first control circuit board 161 is mainly used to achieve the purpose of controlling the external unit of the refrigeration system, and the second control circuit board 162 is mainly used to achieve the purpose of controlling the internal unit of the refrigeration system. That is, the first control circuit board 161 is mainly used to provide corresponding drive signals to the PFC circuit 12, the fan control module 13, the compressor control module 14 and the water pump control module 15, and the second control circuit board 162 is mainly used to control the first control circuit board 161, provide a human-computer interaction interface, and display the input data and output data of the refrigeration system, so that people can debug the refrigeration system.

[0094] Obviously, the technical solution provided by this embodiment can relatively improve the working performance of the central control module.

[0095] As a preferred implementation, the first control circuit board 161 includes:

[0096] First MCU;

[0097] An RS485 interface provided on the first MUC;

[0098] A first auxiliary power supply connected to the first MCU and used to provide a source of electric energy;

[0099] The temperature sensor T1 is connected to the first MCU and is used to detect the temperature value of each device;

[0100] The voltage sensor T2 is connected to the first MCU and is used to detect the voltage value of each device;

[0101] The current sensor T3 is connected to the first MCU and is used to detect the current value of each device;

[0102] The fan module is connected to the first MCU via an optical coupler and is used for dissipating heat for the first MCU.

[0103] Specifically, the first control circuit board is provided with a first MCU, and the first MCU is provided with an RS485 interface, a first auxiliary power supply, a temperature sensor T1, a voltage sensor T2, a current sensor T3 and a fan module. The fan module includes FAN1 and FAN2, which are connected to the first MCU through a first optical coupler U1 and a second optical coupler U2, respectively. The RS485 interface is connected to the first MCU through a third optical coupler U3 and a fourth optical coupler U4. The purpose of connecting the optical coupler to the first MCU is to improve the anti-interference ability of the first MCU and enhance the electrical isolation performance of the input circuit and the output circuit.

[0104] Obviously, through the technical solution provided in this embodiment, the purpose of controlling the PFC circuit, the fan control module, the compressor control module and the water pump control module by using the first control circuit board can be achieved.

[0105] As a preferred embodiment, the second control circuit board 162 includes:

[0106] Second MCU;

[0107] A second auxiliary power supply connected to the second MCU and used to provide a source of electrical energy;

[0108] A drive control module connected to the second MCU for performing signal conversion;

[0109] A CAN interface provided on the second MCU;

[0110] An RS485 interface provided on the second MCU;

[0111] An analog input module and an analog output module are arranged on the second MCU;

[0112] A digital quantity input module and a digital quantity output module are arranged on the second MCU;

[0113] An electromagnetic expansion valve connected to the second MCU and used for throttling and reducing the pressure of the refrigeration system.

[0114] In this embodiment, a second MCU, a second auxiliary power supply, and a drive control module are arranged in the second control circuit board, and a CAN (Controller Area Network) interface, an RS (Recommended Standard) 485 interface, an electromagnetic expansion valve, an analog input module, an analog output module, a digital input module, and a digital output module are arranged on the second MCU.

[0115] exist Figure 4 In the figure, DO1, DO2, DO3 and DO4 form a digital output module, DI is a digital output module, AI is an analog input module, AO is an analog output module, the CAN interface is connected to the second MCU through the fifth optical coupler U5 and the sixth optical coupler U6, and the RS485 interface is connected to the second MCU through the seventh optical coupler U7 and the eighth optical coupler U8. The drive control module is used to realize the signal interaction between the first MCU and the second MCU.

[0116] It should be noted that the second auxiliary power supply uses a 12V supply voltage to power the digital output modules DO1, DO2, DO3 and DO4, and uses a 3.3V supply voltage to power the second MCU.

[0117] Obviously, through the technical solution provided in this embodiment, the purpose of using the second control circuit board to control the first control circuit board, providing a human-computer interaction interface, and displaying input data and output data can be achieved.

[0118] As a preferred implementation, the second control circuit board 162 is stacked on the first control circuit board 161 via support columns.

[0119] In this embodiment, in order to further reduce the space occupied by the electric control box, the second control circuit board 162 can be stacked on the first control circuit board 161 using support columns. At this time, the first control circuit board 161 and the second control circuit board 162 can communicate through a short wiring harness.

[0120] In this case, the first control circuit board 161 is mainly controlled by strong electricity, and the second control circuit board 162 is mainly controlled by weak electricity, so that the weak electricity control area and the strong electricity control area are separated, thereby ensuring the anti-interference and safety of the central control module. Specifically, in actual applications, the second control circuit board 162 can be stacked on the first control circuit board 161 using studs.

[0121] Obviously, the technical solution provided in this embodiment can reduce the space volume occupied by the electric control box.

[0122] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0123] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0124] The above is a detailed introduction to an electric control box for a refrigeration system provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. An electric control box used in a refrigeration system, characterized in that: include: Filter module, used to filter out EMI signals in AC power; A PFC circuit, connected to the filter module, for reducing harmonic current in the AC power and improving the power factor of the AC power; A fan control module, connected to the PFC circuit and the fan in the refrigeration system, for controlling the speed of the fan; a compressor control module connected to the PFC circuit and the compressor in the refrigeration system, and configured to control the compressor through a first IPM module; a water pump control module connected to the PFC circuit and the water pump in the refrigeration system, and configured to control the water pump through a second IPM module; The central control module is connected to the PFC circuit, the fan control module, the compressor control module and the water pump control module, and is used to provide driving signals to the PFC circuit, the fan control module, the compressor control module and the water pump control module respectively.

2. The electric control box used in a refrigeration system according to claim 1, characterized in that: The filtering module includes: a fuse, a first varistor, a second varistor, a gas discharge tube, a first X capacitor, a second X capacitor, a first common mode inductor and a second common mode inductor; Wherein, two ends of the AC voltage source are respectively connected to the first end of the fuse and the first end of the first varistor, the second end of the fuse is respectively connected to the first end of the first X capacitor, the first end of the second varistor and the first end of the first common-mode inductor, the second end of the first varistor and the second end of the second varistor are both connected to the first end of the gas discharge tube, the second end of the gas discharge tube is grounded, the second end of the first X capacitor is connected to the second end of the first common-mode inductor, the third end of the first common-mode inductor is respectively connected to the first end of the second X capacitor and the first end of the second common-mode inductor, and the fourth end of the first common-mode inductor is respectively connected to the second end of the second X capacitor and the second end of the second common-mode inductor; Correspondingly, the third end of the second common-mode inductor and the fourth end of the common-mode inductor are output ends of the filtering module respectively.

3. The electric control box used in a refrigeration system according to claim 2, characterized in that: The coils of the first common-mode inductor and the second common-mode inductor are both in the form of flat wires, the annular magnetic cores of the first common-mode inductor and the second common-mode inductor are both flatly arranged on a circuit board, and a thermally conductive silicone pad is attached to one side of the first common-mode inductor and the second common-mode inductor close to the circuit board.

4. The electric control box used in a refrigeration system according to claim 1, characterized in that: The fan control module includes: a first resistor, a thyristor and a first controllable switch; Among them, the first end of the first resistor is respectively connected to the first end of the first controllable switch and the output end of the filter module, the second end of the first resistor is respectively connected to the second end of the first controllable switch and the negative electrode of the thyristor, and the positive electrode of the thyristor is connected to the AC fan in the refrigeration system; the control end of the first controllable switch and the control end of the thyristor are both used to receive the drive signal sent by the central control module.

5. The electric control box used in a refrigeration system according to claim 1, characterized in that: The PFC circuit comprises: a rectifier bridge for rectifying the alternating current, a second controllable switch, a diode and a second resistor; Among them, the first end of the inductor in the refrigeration system is connected to the output end of the rectifier, the second end of the inductor is respectively connected to the positive electrode of the diode and the first end of the second controllable switch, the second end of the second controllable switch is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the control end of the second controllable switch is used to receive the drive signal sent by the central control module.

6. The electric control box used in a refrigeration system according to claim 1, characterized in that: The compressor control module includes: a first capacitor, a third controllable switch, a fourth controllable switch, a fifth controllable switch, a sixth controllable switch, a seventh controllable switch, an eighth controllable switch, a third resistor, a fourth resistor and a fifth resistor; Wherein, the first end of the third controllable switch, the first end of the fourth controllable switch and the first end of the fifth controllable switch are all connected to the DC bus, the output end of the PFC circuit is connected to the DC bus, the first end of the first capacitor is connected to the DC bus, the second end of the first capacitor is grounded, the second end of the third controllable switch is connected to the first end of the sixth controllable switch, the second end of the fourth controllable switch is connected to the first end of the seventh controllable switch, the second end of the fifth controllable switch is connected to the first end of the eighth controllable switch, the second end of the sixth controllable switch is connected to the first end of the third resistor, the second end of the seventh ... and the second end of the sixth controllable switch is connected to the first end of the third resistor. The first end of the eighth controllable switch is connected to the first end of the fourth resistor, the second end of the eighth controllable switch is connected to the first end of the fifth resistor, the second end of the third resistor, the second end of the fourth resistor and the second end of the fifth resistor are all grounded; the control end of the third controllable switch, the control end of the fourth controllable switch, the control end of the fifth controllable switch, the control end of the sixth controllable switch, the control end of the seventh controllable switch and the control end of the eighth controllable switch are all used to receive the driving signal sent by the central control module, and the second end of the third controllable switch, the second end of the fourth controllable switch and the second end of the fifth controllable switch are respectively connected to the compressor.

7. The electric control box used in a refrigeration system according to claim 1, characterized in that: The central control module comprises: A first control circuit board, used for providing a driving signal to the PFC circuit, the fan control module, the compressor control module and the water pump control module; The second control circuit board is used to control the first control circuit board, provide a human-computer interaction interface, and display input data and output data.

8. The electric control box used in a refrigeration system according to claim 7, characterized in that: The first control circuit board comprises: First MCU; An RS485 interface provided on the first MUC; A first auxiliary power supply connected to the first MCU and used to provide a source of electrical energy; A temperature sensor, connected to the first MCU, for detecting the temperature value of each device; A voltage sensor, connected to the first MCU, for detecting the voltage value of each device; A current sensor, connected to the first MCU, for detecting the current value of each device; The fan module is connected to the first MCU via an optical coupler and is used for dissipating heat for the first MCU.

9. The electric control box used in a refrigeration system according to claim 7, characterized in that: The second control circuit board comprises: Second MCU; A second auxiliary power supply connected to the second MCU and used to provide a source of electrical energy; A drive control module connected to the second MCU and used for performing signal conversion; A CAN interface provided on the second MCU; An RS485 interface provided on the second MCU; An analog input module and an analog output module are provided on the second MCU; A digital quantity input module and a digital quantity output module are arranged on the second MCU; An electromagnetic expansion valve connected to the second MCU and used for throttling and reducing the pressure of the refrigeration system.

10. The electric control box used in a refrigeration system according to claim 7, characterized in that: The second control circuit board is stacked on the first control circuit board through supporting columns.

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