Compressor and DC / DC converter integrated system and control method thereof

Abstract

The invention provides an integrated system of a compressor and a DC / DC converter and a control method of the integrated system, the integrated system replaces a group of half bridges of a primary single-phase inverter bridge of the DC / DC converter by multiplexing a three-phase inverter bridge of the compressor, the use number of single-phase inverter bridge power devices of the DC / DC converter can be reduced, and meanwhile, the power consumption of the single-phase inverter bridge power devices of the DC / DC converter is reduced. The motor winding of the compressor is reused as the auxiliary inductor of the primary side of the DC / DC converter, the transformer specification of the DC / DC converter can be reduced, and the use of input capacitors can be reduced by sharing the high-voltage side input capacitor of the compressor and the high-voltage side input capacitor of the DC / DC converter. Therefore, topological multiplexing integration of the compressor and the DC / DC converter is realized, the use specification of the device is effectively reduced, and the cost, the size and the weight are effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to an integrated system of a compressor and a DC / DC converter and a control method thereof. Background Art

[0002] In recent years, with the gradual strengthening of environmental awareness, the promotion and popularization of new energy vehicles has become faster and faster, and cost, space utilization, and lightweight have become increasingly important. Air conditioning compressors and DC / DC converters are important components of new energy vehicles. Among them, air conditioning compressors are the core components of automobile air conditioning systems, playing the role of compressing and transporting refrigerant vapor, while DC / DC converters are key components of automobile power systems, and their main function is to effectively convert the high voltage of the power battery pack into a stable low voltage. At present, the integration solution of air conditioning compressors and DC / DC converters in new energy vehicles is mainly physical structure integration. The components inside the air conditioning compressor and DC / DC converter are used independently, and their quantity and specifications are basically the same as non-integrated solutions, so they have not effectively reduced costs, volume, and weight. Summary of the invention

[0003] The purpose of this application is to provide an integrated system of a compressor and a DC / DC converter and a control method thereof, aiming to solve the problem that the integrated solution of the air-conditioning compressor and the DC / DC converter in the related art does not effectively reduce the cost, volume and weight.

[0004] In the first aspect, the present application provides an integrated system of a compressor and a DC / DC converter, including a power supply, a positive contactor, a negative contactor, a DC bus capacitor, a DC / DC single-phase inverter bridge, a compressor stator winding, a transformer, a first rectifier diode, a second rectifier diode, and a DC / DC converter output capacitor; the DC / DC single-phase inverter bridge includes a compressor three-phase inverter bridge and a half-bridge circuit; wherein: the two ends of the DC bus capacitor are connected to the positive and negative electrodes of the power supply through the positive contactor and the negative contactor respectively; the compressor three-phase inverter bridge and The DC bus capacitors are connected in parallel; the output end of the compressor three-phase inverter bridge is connected to the compressor stator winding; one end of the primary side of the transformer is connected to the neutral point of the compressor stator winding, and the other end is connected to the output end of the half-bridge circuit; one end of the secondary side of the transformer is connected to the positive electrode of the first rectifier diode, and the other end is connected to the positive electrode of the second rectifier diode; one end of the DC / DC converter output capacitor is connected to the negative electrode of the first rectifier diode and the negative electrode of the second rectifier diode, and the other end is connected to the center of the secondary side of the transformer.

[0005] In the above implementation process, an integrated system of a compressor and a DC / DC converter is provided. The integrated system can reduce the number of power devices used in the single-phase inverter bridge of the DC / DC converter by reusing the three-phase inverter bridge of the compressor to replace a group of half-bridges of the primary single-phase inverter bridge of the DC / DC converter. At the same time, by reusing the motor winding of the compressor as the auxiliary inductor of the primary side of the DC / DC converter, the transformer specifications of the DC / DC converter can be reduced. Moreover, by sharing the input capacitor on the high-voltage side of the compressor with the input capacitor on the high-voltage side of the DC / DC converter, the use of the input capacitor can be reduced. In this way, the topological reuse integration of the compressor and the DC / DC converter is realized, the use specifications of the devices are effectively reduced, and the cost, volume and weight are effectively reduced.

[0006] Furthermore, in some examples, it also includes: a control unit, the control unit is used to control the on-off state of the positive contactor, the negative contactor and each power switch device in the DC / DC single-phase inverter bridge according to the working mode of the integrated system; the working mode of the integrated system includes a first working mode, a second working mode, a third working mode and a fourth working mode; wherein the first working mode is a working mode corresponding to the DC / DC converter and the compressor being on standby at the same time; the second working mode is a working mode corresponding to the DC / DC converter being started alone; the third working mode is a working mode corresponding to the compressor being started alone; the fourth working mode is a working mode corresponding to the DC / DC converter and the compressor being started at the same time.

[0007] In the above implementation process, the working modes of the integrated system can be divided into four modes, namely: the DC / DC converter and the compressor are on standby at the same time, the DC / DC converter is started alone, the compressor is started alone, and the DC / DC converter and the compressor are started at the same time. By controlling the on-off state of each switching device, the switching of these four working modes can be realized.

[0008] Furthermore, in some examples, the control unit is specifically configured to: control all power switch devices in the DC / DC single-phase inverter bridge to turn off when the integrated system enters the first operating mode.

[0009] In the above implementation process, a control method is provided for realizing the simultaneous standby of the DC / DC converter and the compressor.

[0010] Further, in some examples, the control unit is specifically used to: when the integrated system enters the second working mode, control the positive contactor and the negative contactor to be turned on; if the DC / DC converter is in the inverter output process, control the power switching devices of the upper bridge arm in the three-phase inverter bridge of the compressor to be turned on at the same time, and the power switching devices of the lower bridge arm in the three-phase inverter bridge of the compressor to be turned off at the same time, and control the power switching devices of the upper bridge arm in the half-bridge circuit to be turned off, and the power switching devices of the lower bridge arm in the half-bridge circuit to be turned on; if the DC / DC converter is in the freewheeling process, control the power switching devices of the upper bridge arm in the three-phase inverter bridge of the compressor to be turned off at the same time, and the power switching devices of the lower bridge arm in the three-phase inverter bridge of the compressor to be turned on at the same time, and control the power switching devices of the upper bridge arm in the half-bridge circuit to be turned on, and the power switching devices of the lower bridge arm in the half-bridge circuit to be turned off.

[0011] In the above implementation process, a control method for realizing independent operation of a DC / DC converter is provided.

[0012] Further, in some examples, the compressor three-phase inverter bridge includes a first phase half bridge, a second phase half bridge and a third phase half bridge; the control unit is specifically used to: when the integrated system enters the third working mode, control the positive contactor and the negative contactor to be turned on; if the compressor is in the inverter output process, control the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge and the lower bridge arm of the third phase half bridge to be turned on, and control the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge and the upper bridge arm of the third phase half bridge to be turned off; if the compressor is in the freewheeling process, control the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge and the lower bridge arm of the third phase half bridge to be turned off, and control the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge and the upper bridge arm of the third phase half bridge to be turned on.

[0013] In the above implementation process, a control method for realizing independent operation of the compressor is provided.

[0014] Further, in some examples, the control unit is specifically used to: when the integrated system enters the fourth working mode, according to the working requirements of the DC / DC converter, calculate the control instructions of all power switching devices in the DC / DC single-phase inverter bridge when the DC / DC converter works alone and the three-phase current of the compressor in the corresponding state; according to the working requirements of the compressor, calculate the control instructions of all power switching devices in the three-phase inverter bridge of the compressor when the compressor works alone and the three-phase current of the compressor in the corresponding state; add and synthesize the obtained control instructions or three-phase currents to obtain the final control instructions when the DC / DC converter and the compressor work simultaneously.

[0015] In the above implementation process, a decoupling control method is provided for a DC / DC converter and a compressor that are in working state at the same time. By decoupling the operation control of the DC / DC converter and the operation control of the compressor, mutual interference between the DC / DC converter and the compressor during operation is effectively avoided.

[0016] Further, in some examples, the compressor three-phase inverter bridge includes a first-phase half-bridge, a second-phase half-bridge and a third-phase half-bridge; the control unit is specifically used to: when the integrated system enters the fourth working mode, and the first-phase current and the second-phase current are obtained by adding the obtained three-phase currents to obtain positive values, and the third-phase current is negative, control the positive contactor and the negative contactor to be turned on; if the DC / DC converter and the compressor jointly invert the output, control the upper bridge arm of the first-phase half-bridge, the upper bridge arm of the second-phase half-bridge, the lower bridge arm of the third-phase half-bridge and the power switch of the lower bridge arm of the half-bridge circuit The device is turned on, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned off; if the DC / DC converter and the compressor are in freewheeling mode together, the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half-bridge circuit are turned off, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned on.

[0017] In the above implementation process, a control method for realizing simultaneous operation of a DC / DC converter and a compressor is provided.

[0018] In a second aspect, the present application provides a control method for an integrated system of a compressor and a DC / DC converter as described in any one of the first aspects, which is applied to the control unit, and the control method includes: when the integrated system enters a corresponding working mode in which the DC / DC converter and the compressor are started simultaneously, according to the working requirements of the DC / DC converter, calculating the control instructions of all power switching devices in the DC / DC single-phase inverter bridge when the DC / DC converter works alone and the three-phase current of the compressor in the corresponding state; according to the working requirements of the compressor, calculating the control instructions of all power switching devices in the three-phase inverter bridge of the compressor when the compressor works alone and the three-phase current of the compressor in the corresponding state; adding and synthesizing the obtained control instructions or three-phase currents to obtain the final control instructions when the DC / DC converter and the compressor work simultaneously.

[0019] Further, in some examples, the compressor three-phase inverter bridge includes a first-phase half-bridge, a second-phase half-bridge and a third-phase half-bridge; the control method also includes: when the integrated system enters the fourth working mode and the first-phase current and the second-phase current are obtained by adding the obtained three-phase currents to obtain positive values, and the third-phase current is negative, controlling the positive contactor and the negative contactor to be turned on; if the DC / DC converter and the compressor jointly invert the output, controlling the upper bridge arm of the first-phase half-bridge, the upper bridge arm of the second-phase half-bridge, the lower bridge arm of the third-phase half-bridge and the power switch of the lower bridge arm of the half-bridge circuit The device is turned on, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned off; if the DC / DC converter and the compressor are in freewheeling mode together, the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half-bridge circuit are turned off, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned on.

[0020] In a third aspect, the present application provides a vehicle, comprising an integrated system as described in any one of the first aspects.

[0021] Other features and advantages disclosed in the present application will be described in the following description, or some features and advantages can be inferred or determined without doubt from the description, or can be learned by implementing the above-mentioned technology disclosed in the present application.

[0022] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of an integrated system of a compressor and a DC / DC converter provided in an embodiment of the present application;

[0025] Figure 2 A schematic diagram of a working state in which a DC / DC converter of an integrated system provided in an embodiment of the present application performs inverter output alone;

[0026] Figure 3 A schematic diagram of a DC / DC converter of an integrated system provided in an embodiment of the present application performing freewheeling operation alone;

[0027] Figure 4 A schematic diagram of a working state in which a compressor of an integrated system provided in an embodiment of the present application performs inverter output alone;

[0028] Figure 5 A schematic diagram of a working state in which a compressor of an integrated system provided in an embodiment of the present application performs freewheeling alone;

[0029] Figure 6 A schematic diagram of a working state of a DC / DC converter and a compressor in common inverter output provided by an embodiment of the present application;

[0030] Figure 7 A schematic diagram of a working state of a DC / DC converter and a compressor in which a current is continuously supplied together provided in an embodiment of the present application;

[0031] Figure 8 A flowchart of a control method for an integrated system of a compressor and a DC / DC converter provided in an embodiment of the present application.

[0032] Description of reference numerals:

[0033] 10-power supply; 20-DC / DC single-phase inverter bridge; 30-compressor stator winding; 40-compressor three-phase inverter bridge; 50-half-bridge circuit; S1-positive contactor; S2-negative contactor; C1-DC bus capacitor; C2-DC / DC converter output capacitor; T1-transformer; D1-first rectifier diode; D2-second rectifier diode; Q1-first power switch device; Q2-second power switch device; Q3-third power switch device; Q4-fourth power switch device; Q5-fifth power switch device; Q6-sixth power switch device; Q7-seventh power switch device; Q8-eighth power switch device. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0035] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0036] As described in the background technology, the integration solution of the air-conditioning compressor and the DC / DC converter in the related art has the problem of not effectively reducing the cost, volume and weight. Based on this, the embodiment of the present application provides an integrated system of a compressor and a DC / DC converter to solve the above problems.

[0037] Next, the embodiments of the present application are introduced:

[0038] like Figure 1 As shown, Figure 1is a schematic diagram of an integrated system of a compressor and a DC / DC converter provided in an embodiment of the present application, wherein the integrated system comprises a power supply 10, a positive contactor S1, a negative contactor S2, a DC bus capacitor C1, a DC / DC single-phase inverter bridge 20, a compressor stator winding 30, a transformer T1, a first rectifier diode D1, a second rectifier diode D2, and a DC / DC converter output capacitor C2; the DC / DC single-phase inverter bridge 20 comprises a compressor three-phase inverter bridge 40 and a half-bridge circuit 50; wherein: the two ends of the DC bus capacitor C1 are connected to the positive and negative electrodes of the power supply 10 through the positive contactor S1 and the negative contactor S2 respectively; the compressor The compressor three-phase inverter bridge 40 is connected in parallel with the DC bus capacitor C1; the output end of the compressor three-phase inverter bridge 40 is connected to the compressor stator winding 30; one end of the primary side of the transformer T1 is connected to the neutral point of the compressor stator winding 30, and the other end is connected to the output end of the half-bridge circuit 50; one end of the secondary side of the transformer T1 is connected to the positive electrode of the first rectifier diode D1, and the other end is connected to the positive electrode of the second rectifier diode D2; one end of the DC / DC converter output capacitor C2 is connected to the negative electrode of the first rectifier diode D1 and the negative electrode of the second rectifier diode D2, and the other end is connected to the center of the secondary side of the transformer T1.

[0039] Among them, the compressor three-phase inverter bridge 40 includes a first power switch device Q1, a second power switch device Q2, a third power switch device Q3, a fourth power switch device Q4, a fifth power switch device Q5 and a sixth power switch device Q6, and the half-bridge circuit 50 includes a seventh power switch device Q7 and an eighth power switch device Q8.

[0040] The above integrated system is a solution that multiplexes and integrates some components of the compressor and the DC / DC converter, which can realize the functions of both the compressor and the DC / DC converter. In the above integrated system, the functions of each component are as follows:

[0041] The power supply 10 provides a DC input power supply for the integrated system, such as a power battery on an electric vehicle;

[0042] The positive contactor S1 controls the connection or disconnection between the positive electrode of the power supply 10 and the system load;

[0043] The negative contactor S2 controls the connection or disconnection between the negative pole of the power supply 10 and the system load;

[0044] The DC bus capacitor C1 realizes the function of voltage stabilization and filtering, and can also provide instantaneous high power for the compressor or DC / DC. That is to say, in the integrated system of this embodiment, the DC bus capacitor C1 can be used as both the high-voltage side input capacitor of the compressor and the high-voltage side input capacitor of the DC / DC converter. In this way, the use of input capacitors can be reduced by sharing the high-voltage side input capacitor of the compressor with the high-voltage side input capacitor of the DC / DC converter.

[0045] Power devices Q1, Q2, Q3, Q4, Q5, and Q6 form a three-phase full-bridge inverter to output three-phase AC power for driving the compressor; power devices Q1, Q2, Q3, Q4, Q5, and Q6 also form a group of half bridges in the DC / DC primary inverter bridge, in which Q1, Q3, and Q5 are connected in parallel to form an upper bridge arm, and Q2, Q4, and Q6 are connected in parallel to form a lower bridge arm;

[0046] Power devices Q7 and Q8 form another half-bridge of the DC / DC primary inverter bridge, and together with the half-bridge composed of Q1, Q2, Q3, Q4, Q5, and Q6, form a single-phase inverter bridge to input single-phase AC power to transformer T1, and also achieve the function of voltage reduction;

[0047] The compressor stator winding 30 generates a rotating magnetic field to drive the compressor rotor to rotate; in the integrated system of this embodiment, the compressor stator winding 30 can also be used as an auxiliary inductor of the DC / DC primary circuit. By reusing the compressor motor winding as the auxiliary inductor of the DC / DC converter primary circuit, the transformer specification of the DC / DC converter can be reduced;

[0048] Transformer T1 realizes the isolation between the high-voltage circuit and the low-voltage circuit of the DC / DC converter, and can also achieve the function of voltage reduction;

[0049] The first rectifier diode D1 and the second rectifier diode D2 are used to rectify the AC power output by the secondary circuit of the transformer T1 into DC power and provide it to the power load;

[0050] The DC / DC converter output capacitor C2 filters and stabilizes the output direct current of the rectifier circuit formed by the first rectifier diode D1 and the second rectifier diode.

[0051] In the above integrated system, the positive electrode of the power supply 10 is connected to one end of the positive contactor S1, and the negative electrode of the power supply 10 is connected to one end of the negative contactor S2; the drain of Q1, the drain of Q3, the drain of Q5, the drain of Q7, and one end of the DC bus capacitor C1 are connected in parallel and connected to the other end of the positive contactor S1; the drain of Q2, the drain of Q4, the drain of Q6, the drain of Q8, and the other end of the DC bus capacitor C1 are connected in parallel and connected to the other end of the negative contactor S2; the source of Q1 is connected to the drain of Q2, and is led out from the connecting line to be connected to one end of the compressor phase A; the source of Q3 is connected to the drain of Q4, and is led out from the connecting line to be connected to one end of the compressor phase B; the source of Q5 is connected to the drain of Q6, and is led out from the connecting line to be connected to one end of the compressor phase C. The source of Q7 is connected to the drain of Q8, and a lead is drawn out from the connecting line to connect to one end of the primary side of the transformer T1; the other end of the compressor phase A, the other end of the phase B, and the other end of the phase C are connected in parallel to form a star point, and a center line is drawn out from the star point to connect to the other end of the primary side of the transformer T1; connecting lines are drawn out from both ends of the secondary side of the transformer T1 and the center, wherein one end of the secondary side is connected to one end of the first rectifier diode D1, the other end of the secondary side is connected to the other end of the second rectifier diode D2, and the center lead is connected to one end of the DC / DC converter output capacitor C2 and the DC output negative electrode; the other end of the first rectifier diode D1 and the other end of the second rectifier diode D2 are connected in parallel, and are connected to the other end of the DC / DC converter output capacitor C2 and the DC output positive electrode. In this way, the DC / DC converter is composed of a power supply, an input capacitor, a single-phase inverter bridge, an isolation transformer, a rectifier bridge, and an output capacitor. It is used to convert a high-voltage power supply, such as the high-voltage electricity of an electric vehicle's power battery, into low-voltage electricity to power the vehicle's low-voltage electrical appliances; the compressor is composed of a power supply, an input capacitor, a three-phase inverter bridge, and a compressor motor, and is used to adjust the pressure and temperature of the vehicle's air-conditioning refrigerant.

[0052] This integrated system of the embodiment of the present application is suitable for the integration of DC / DC converters and compressor parts for pure electric vehicle applications, and is also suitable for the integration of DC / DC converters and drive motor system parts. It also has front-wheel drive and rear-wheel drive platform adaptability, and is also suitable for other automotive fields such as hybrid vehicles.

[0053] In the embodiment of the present application, by reusing the compressor three-phase inverter bridge to replace a group of half-bridges of the DC / DC converter primary single-phase inverter bridge, the number of DC / DC converter single-phase inverter bridge power devices used can be reduced. At the same time, by reusing the compressor motor winding as the auxiliary inductor of the DC / DC converter primary side, the transformer specifications of the DC / DC converter can be reduced. Moreover, by sharing the compressor high-voltage side input capacitor with the DC / DC converter high-voltage side input capacitor, the use of input capacitors can be reduced. In this way, the topological reuse integration of the compressor and the DC / DC converter is achieved, effectively reducing the use specifications of the devices, and effectively reducing the cost, volume and weight.

[0054] In some embodiments, the integrated system of the present application may further include: a control unit, the control unit is used to control the conduction state of the positive contactor, the negative contactor and each power switch device in the DC / DC single-phase inverter bridge according to the working mode of the integrated system; the working mode of the integrated system includes a first working mode, a second working mode, a third working mode and a fourth working mode; wherein the first working mode is a working mode corresponding to the DC / DC converter and the compressor being on standby at the same time; the second working mode is a working mode corresponding to the DC / DC converter being started alone; the third working mode is a working mode corresponding to the compressor being started alone; the fourth working mode is a working mode corresponding to the DC / DC converter being started at the same time as the compressor. The control unit here can be a control circuit responsible for receiving input instructions from an external electronic control unit and controlling all switch devices in the main circuit according to these input instructions. The working modes of the integrated system can be divided into four modes, namely: the DC / DC converter and the compressor are on standby at the same time, the DC / DC converter is started alone, the compressor is started alone, and the DC / DC converter and the compressor are started at the same time. The control unit can switch between the four working modes by controlling the on / off states of the positive contactor S1, the negative contactor S2 and each power switch device in the DC / DC single-phase inverter bridge, namely Q1 to Q8.

[0055] In some embodiments, the control unit is specifically used to: when the integrated system enters the first working mode, control all power switch devices in the DC / DC single-phase inverter bridge to turn off. In other words, the DC / DC converter and the compressor are in standby mode at the same time, and the power devices Q1, Q2, Q3, Q4, Q5, Q6, Q7, and Q8 are all in an open circuit state. In this way, the DC / DC converter and the compressor are in standby mode at the same time.

[0056] In some embodiments, the control unit is specifically used to: when the integrated system enters the second working mode, control the positive contactor and the negative contactor to be turned on; if the DC / DC converter is in the inverter output process, control the power switching devices of the upper bridge arm in the three-phase inverter bridge of the compressor to be turned on at the same time, and the power switching devices of the lower bridge arm in the three-phase inverter bridge of the compressor to be turned off at the same time, and control the power switching devices of the upper bridge arm in the half-bridge circuit to be turned off, and the power switching devices of the lower bridge arm in the half-bridge circuit to be turned on; if the DC / DC converter is in the freewheeling process, control the power switching devices of the upper bridge arm in the three-phase inverter bridge of the compressor to be turned off at the same time, and the power switching devices of the lower bridge arm in the three-phase inverter bridge of the compressor to be turned on at the same time, and control the power switching devices of the upper bridge arm in the half-bridge circuit to be turned on, and the power switching devices of the lower bridge arm in the half-bridge circuit to be turned off. That is to say, the DC / DC converter is started alone, the compressor is in a non-working state, the compressor has no driving torque output and the speed is 0. At this time, the compressor inverter three-phase full-bridge does not perform three-phase AC power inverter output, and is only used for DC-DC converter high-voltage side inverter control and step-down regulation.

[0057] Figure 2 A schematic diagram of the working state of the DC / DC converter of the integrated system provided for the embodiment of the present application for inverter output alone (for the convenience of display, the serial numbers of some devices in the figure are not marked), and the arrow direction in the figure is the current direction. When entering the second working mode, the positive contactor S1 and the negative contactor S2 are controlled to be turned on, the upper bridge arm power devices Q1, Q3, and Q5 are turned on at the same time, the upper bridge arm power device Q7 is turned off, the lower bridge arm power devices Q2, Q4, and Q6 are turned off at the same time, and the lower bridge arm power device Q8 is turned on. At this time, the current flows evenly from the positive pole of the power supply 10 to the power devices Q1, Q3, and Q5, and then flows through the compressor stator winding 30, the primary coil of the transformer T1, the power device Q8, and the negative pole of the power supply 10 in sequence. In this way, the DC / DC converter is realized with inverter output alone.

[0058] Figure 3 A schematic diagram of the working state of the DC / DC converter of the integrated system provided in the embodiment of the present application for freewheeling alone (for the convenience of display, the serial numbers of some devices in the figure are not marked), and the direction of the arrow in the figure is the direction of the current. When entering the second working mode, the positive contactor S1 and the negative contactor S2 are controlled to be turned on, the upper bridge arm power devices Q1, Q3, and Q5 are turned off at the same time, the upper bridge arm power device Q7 is turned on, the lower bridge arm power devices Q2, Q4, and Q6 are turned on at the same time, and the lower bridge arm power device Q8 is turned off; at this time, the current flows from the compressor stator winding 30 through the primary coil of the transformer T1, the power device Q7, the positive pole of the power supply 10, and the negative pole of the power supply 10, and then flows evenly to the power devices Q2, Q4, and Q6. In this way, the DC / DC converter is freewheeling alone.

[0059] In the second working mode, the currents passing through the compressor stator winding phases A, B, and C are consistent in magnitude and direction, so the three-phase magnetic fields generated by the compressor stator winding cancel each other out, the synthetic magnetic field is zero, and the compressor has no torque output.

[0060] In some embodiments, the compressor three-phase inverter bridge includes a first phase half bridge, a second phase half bridge and a third phase half bridge; the control unit is specifically used to: when the integrated system enters the third working mode, control the positive contactor and the negative contactor to be turned on; if the compressor is in the inverter output process, control the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge and the lower bridge arm of the third phase half bridge to be turned on, and control the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge and the upper bridge arm of the third phase half bridge to be turned off; if the compressor is in the freewheeling process, control the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge and the lower bridge arm of the third phase half bridge to be turned off, and control the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge and the upper bridge arm of the third phase half bridge to be turned on. That is to say, in the third working mode, the compressor is started alone and the DC / DC converter has no output. At this time, the compressor inverter three-phase full-bridge only performs three-phase AC power inverter output, and does not perform DC / DC converter high-voltage side inverter control and step-down regulation.

[0061] Figure 4 It is a schematic diagram of the working state of the compressor of the integrated system provided in the embodiment of the present application for inverter output alone (for the convenience of display, the serial numbers of some devices in the figure are not marked), and the direction of the arrow in the figure is the direction of current. When entering the third working mode, the positive contactor S1 and the negative contactor S2 are controlled to be turned on; the upper bridge arm power devices Q1 and Q3 are turned on, the upper bridge arm power device Q5 is turned off, the lower bridge arm power devices Q2 and Q4 are turned off, and the lower bridge arm power device Q6 is turned on; at this time, the current flows from the positive pole of the power supply 10 through the power devices Q1, Q3, the compressor stator winding 30, the power device Q6, and the negative pole of the power supply 10. In this way, the compressor achieves independent inverter output.

[0062] Figure 5 It is a schematic diagram of the working state of the compressor of the integrated system provided in the embodiment of the present application performing freewheeling alone (for the convenience of display, the serial numbers of some devices in the figure are not marked), and the direction of the arrow in the figure is the direction of the current. When entering the third working mode, the positive contactor S1 and the negative contactor S2 are controlled to be turned on; the upper bridge arm power devices Q1 and Q3 are turned off, the upper bridge arm power device Q5 is turned on, the lower bridge arm power devices Q2 and Q4 are turned on, and the lower bridge arm power device Q6 is turned off; at this time, the current flows from the compressor stator winding 30 through the power device Q5, the positive pole of the power supply 10, the negative pole of the power supply 10, and the power devices Q2 and Q4 in sequence. In this way, the compressor can achieve freewheeling alone.

[0063] In the third working mode, the composite magnetic field of the compressor's A-phase, B-phase, and C-phase is a rotating magnetic field, which drives the compressor to rotate.

[0064] In some embodiments, the control unit is specifically used to: when the integrated system enters the fourth working mode, according to the working requirements of the DC / DC converter, calculate the control instructions of all power switching devices in the DC / DC single-phase inverter bridge when the DC / DC converter works alone and the three-phase current of the compressor in the corresponding state; according to the working requirements of the compressor, calculate the control instructions of all power switching devices in the three-phase inverter bridge of the compressor when the compressor works alone and the three-phase current of the compressor in the corresponding state; add and synthesize the obtained control instructions or three-phase currents to obtain the final control instructions when the DC / DC converter and the compressor work simultaneously.

[0065] That is to say, when the DC / DC converter and the compressor are in working state at the same time, the compressor inverter three-phase full bridge needs to perform not only three-phase AC inverter output, but also DC / DC converter high-voltage side inverter control and step-down regulation. In order to avoid mutual interference between the DC / DC converter and the compressor during operation, the DC / DC converter operation control and the compressor operation control are decoupled. Specifically, the control instructions of the power devices Q1~Q8 when the DC / DC converter works alone and the three-phase current of the compressor in this state are calculated according to the working requirements of the DC / DC converter; the control instructions of the power devices Q1~Q6 when the compressor works alone and the three-phase current of the compressor in this state are calculated according to the working requirements of the compressor; the control instructions or three-phase currents obtained by the two are added and synthesized to obtain the final control instruction for the simultaneous operation of the two. Under the execution and regulation of the final control instruction, the magnetic field generated by the three-phase winding of the compressor is synthesized by a rotating magnetic field (obtained under the control of the compressor) and a zero magnetic field (obtained under the control of the DC / DC converter). At this time, the operation of the compressor is basically not affected by the operation of the DC / DC converter. Whether the circuit loop of the DC / DC converter is operating or not can be determined by the power devices Q7 and Q8. By controlling the power devices Q7 and Q8 according to the instructions when the DC / DC converter works alone, the working requirements of the DC / DC converter can be met and are basically not affected by the compressor control.

[0066] Further, in some embodiments, the control unit is specifically used for: when the integrated system enters the fourth working mode, and the first phase current and the second phase current are obtained by adding the obtained three-phase currents to obtain positive values, and the third phase current is negative, controlling the positive contactor and the negative contactor to be turned on; if the DC / DC converter and the compressor jointly invert the output, controlling the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge, and the power switch devices of the lower bridge arm of the half bridge circuit to be turned on, and controlling the first phase half bridge circuit to be turned on. The power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned off; if the DC / DC converter and the compressor are in freewheeling mode together, the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half-bridge circuit are turned off, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned on.

[0067] Figure 6 It is a schematic diagram of a working state of the DC / DC converter and the compressor provided in the embodiment of the present application for common inverter output (for the convenience of display, the serial numbers of some devices in the figure are not marked), and the arrow direction in the figure is the current direction. In this working state, the three-phase current of the DC / DC converter and the compressor is calculated and synthesized to obtain that the current of phase A and phase B is positive, and the current of phase C is negative. When entering this working state, the positive contactor S1 and the negative contactor S2 are controlled to be turned on; the upper bridge arm power devices Q1 and Q3 are turned on, the upper bridge arm power devices Q5 and Q7 are turned off, the lower bridge arm power devices Q2 and Q4 are turned off, and the lower bridge arm power devices Q6 and Q8 are turned on; at this time, the current flows from the positive pole of the power supply 10 through the power devices Q1 and Q3, the A phase and the B phase of the compressor stator winding 30, the C phase of the compressor stator winding 30 and the transformer T1, the power devices Q6 and Q8, and the negative pole of the power supply 10. In this way, the DC / DC converter and the compressor are jointly inverter output.

[0068] Figure 7It is a schematic diagram of a working state of the DC / DC converter and the compressor provided in the embodiment of the present application in which the current is continuously flowing together (for the convenience of display, the serial numbers of some devices in the figure are not marked), and the arrow direction in the figure is the current direction. In this working state, the three-phase current of the DC / DC converter and the compressor is calculated and synthesized to obtain that the current of phase A and phase B is positive, and the current of phase C is negative. When entering this working state, the positive contactor S1 and the negative contactor S2 are controlled to be turned on; the upper bridge arm power devices Q1 and Q3 are turned off, the upper bridge arm power devices Q5 and Q7 are turned on, the lower bridge arm power devices Q2 and Q4 are turned on, and the lower bridge arm power devices Q6 and Q8 are turned off; at this time, the current flows from the A phase and the B phase of the compressor stator winding 30 through the C phase of the compressor stator winding 30 and the transformer T1, the power devices Q5 and Q7, the positive pole of the power supply 10, the negative pole of the power supply 10, and the power devices Q2 and Q4. In this way, the DC / DC converter and the compressor are continuously flowing together.

[0069] like Figure 8 As shown, Figure 8 : is a flow chart of a control method of an integrated system of a compressor and a DC / DC converter provided in an embodiment of the present application. The integrated system is an integrated system in any of the aforementioned embodiments. The control method is applied to a control unit, including:

[0070] In step 801, when the integrated system enters a corresponding working mode in which the DC / DC converter and the compressor are started simultaneously, the control instructions of all power switch devices in the DC / DC single-phase inverter bridge when the DC / DC converter works alone and the three-phase current of the compressor in the corresponding state are calculated according to the working requirements of the DC / DC converter;

[0071] In step 802, according to the working requirements of the compressor, the control instructions of all power switch devices in the three-phase inverter bridge of the compressor and the three-phase current of the compressor in the corresponding state are calculated when the compressor works alone;

[0072] In step 803, the obtained control instructions or three-phase currents are added and synthesized to obtain a final control instruction when the DC / DC converter and the compressor work simultaneously.

[0073] In some embodiments, the compressor three-phase inverter bridge includes a first-phase half-bridge, a second-phase half-bridge and a third-phase half-bridge; the control method also includes: when the integrated system enters the fourth working mode and the first-phase current and the second-phase current are obtained by adding the obtained three-phase currents, and the third-phase current is negative, controlling the positive contactor and the negative contactor to be turned on; if the DC / DC converter and the compressor jointly invert the output, controlling the upper bridge arm of the first-phase half-bridge, the upper bridge arm of the second-phase half-bridge, the lower bridge arm of the third-phase half-bridge and the power switching devices of the lower bridge arm of the half-bridge circuit The power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are turned on, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are controlled to be turned off if the DC / DC converter and the compressor are jointly freewheeling. The power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half-bridge circuit are controlled to be turned on.

[0074] The implementation process of each step in the above method is detailed in the introduction of the relevant content in the above system, which will not be repeated here.

[0075] Some embodiments of the present application also provide a vehicle, which includes the integrated system involved in any of the aforementioned embodiments.

[0076] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0077] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0078] 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 existence of other identical elements in the process, method, article or device including the elements.

Claims

1. An integrated system of a compressor and a DC / DC converter, characterized in that: It includes a power supply, a positive contactor, a negative contactor, a DC bus capacitor, a DC / DC single-phase inverter bridge, a compressor stator winding, a transformer, a first rectifier diode, a second rectifier diode, and a DC / DC converter output capacitor; the DC / DC single-phase inverter bridge includes a compressor three-phase inverter bridge and a half-bridge circuit; wherein: The two ends of the DC bus capacitor are connected to the positive and negative electrodes of the power supply through the positive contactor and the negative contactor respectively; the compressor three-phase inverter bridge is connected in parallel with the DC bus capacitor; the output end of the compressor three-phase inverter bridge is connected to the compressor stator winding; One end of the primary side of the transformer is connected to the neutral point of the compressor stator winding, and the other end is connected to the output end of the half-bridge circuit; one end of the secondary side of the transformer is connected to the positive electrode of the first rectifier diode, and the other end is connected to the positive electrode of the second rectifier diode; one end of the output capacitor of the DC / DC converter is connected to the negative electrode of the first rectifier diode and the negative electrode of the second rectifier diode, and the other end is connected to the center of the secondary side of the transformer.

2. The integrated system according to claim 1, characterized in that: Also includes: A control unit, the control unit is used to control the on-off state of the positive contactor, the negative contactor and each power switch device in the DC / DC single-phase inverter bridge according to the working mode of the integrated system; the working mode of the integrated system includes a first working mode, a second working mode, a third working mode and a fourth working mode; wherein the first working mode is a working mode corresponding to the DC / DC converter and the compressor being on standby at the same time; the second working mode is a working mode corresponding to the DC / DC converter being started alone; the third working mode is a working mode corresponding to the compressor being started alone; and the fourth working mode is a working mode corresponding to the DC / DC converter and the compressor being started at the same time.

3. The integrated system according to claim 2, characterized in that: The control unit is specifically used for: When the integrated system enters the first working mode, all power switch devices in the DC / DC single-phase inverter bridge are controlled to be turned off.

4. The integrated system according to claim 2, characterized in that: The control unit is specifically used for: When the integrated system enters the second working mode, controlling the positive contactor and the negative contactor to be turned on; If the DC / DC converter is in the inverter output process, the power switch devices of the upper bridge arm in the three-phase inverter bridge of the compressor are controlled to be turned on at the same time, and the power switch devices of the lower bridge arm in the three-phase inverter bridge of the compressor are turned off at the same time, and the power switch device of the upper bridge arm in the half-bridge circuit is controlled to be turned off, and the power switch device of the lower bridge arm in the half-bridge circuit is turned on; If the DC / DC converter is in the freewheeling process, the power switching devices of the upper bridge arm in the three-phase inverter bridge of the compressor are controlled to be turned off at the same time, and the power switching devices of the lower bridge arm in the three-phase inverter bridge of the compressor are controlled to be turned on at the same time, and the power switching devices of the upper bridge arm in the half-bridge circuit are controlled to be turned on, and the power switching devices of the lower bridge arm in the half-bridge circuit are turned off.

5. The integrated system according to claim 2, characterized in that: The compressor three-phase inverter bridge includes a first phase half bridge, a second phase half bridge and a third phase half bridge; the control unit is specifically used for: When the integrated system enters the third working mode, controlling the positive contactor and the negative contactor to be turned on; If the compressor is in the inverter output process, the power switch devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge and the lower bridge arm of the third phase half bridge are controlled to be turned on, and the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge and the upper bridge arm of the third phase half bridge are controlled to be turned off; If the compressor is in the freewheeling process, the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge and the lower bridge arm of the third phase half bridge are controlled to be turned off, and the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge and the upper bridge arm of the third phase half bridge are controlled to be turned on.

6. The integrated system according to claim 2, characterized in that: The control unit is specifically used for: When the integrated system enters the fourth working mode, according to the working requirements of the DC / DC converter, the control instructions of all power switch devices in the DC / DC single-phase inverter bridge when the DC / DC converter works alone and the three-phase current of the compressor in the corresponding state are calculated; According to the working requirements of the compressor, the control instructions of all power switch devices in the three-phase inverter bridge of the compressor and the three-phase current of the compressor in the corresponding state are calculated when the compressor works alone; The obtained control instructions or three-phase currents are added and synthesized to obtain a final control instruction when the DC / DC converter and the compressor work simultaneously.

7. The integrated system according to claim 6, characterized in that: The compressor three-phase inverter bridge includes a first phase half bridge, a second phase half bridge and a third phase half bridge; the control unit is specifically used for: When the integrated system enters the fourth working mode and the first phase current and the second phase current obtained by adding the three-phase currents are positive and the third phase current is negative, the positive contactor and the negative contactor are controlled to be turned on; If the DC / DC converter and the compressor jointly invert the output, the power switch devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half bridge circuit are controlled to be turned on, and the power switch devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half bridge circuit are controlled to be turned off; If the DC / DC converter and the compressor jointly freewheel, the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half-bridge circuit are controlled to be turned off, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are controlled to be turned on.

8. A control method for an integrated system of a compressor and a DC / DC converter according to any one of claims 2 to 7, characterized in that: applied to the control unit; The control method comprises: When the integrated system enters a corresponding working mode in which the DC / DC converter and the compressor are started simultaneously, the control instructions of all power switch devices in the DC / DC single-phase inverter bridge when the DC / DC converter works alone and the three-phase current of the compressor in the corresponding state are calculated according to the working requirements of the DC / DC converter; According to the working requirements of the compressor, the control instructions of all power switch devices in the three-phase inverter bridge of the compressor and the three-phase current of the compressor in the corresponding state are calculated when the compressor works alone; The obtained control instructions or three-phase currents are added and synthesized to obtain a final control instruction when the DC / DC converter and the compressor work simultaneously.

9. The control method according to claim 8, characterized in that: The compressor three-phase inverter bridge includes a first phase half bridge, a second phase half bridge and a third phase half bridge; the control method also includes: When the integrated system enters the fourth working mode and the first phase current and the second phase current obtained by adding the three-phase currents are positive and the third phase current is negative, the positive contactor and the negative contactor are controlled to be turned on; If the DC / DC converter and the compressor jointly invert the output, the power switch devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half bridge circuit are controlled to be turned on, and the power switch devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half bridge circuit are controlled to be turned off; If the DC / DC converter and the compressor jointly freewheel, the power switching devices of the upper bridge arm of the first phase half bridge, the upper bridge arm of the second phase half bridge, the lower bridge arm of the third phase half bridge and the lower bridge arm of the half-bridge circuit are controlled to be turned off, and the power switching devices of the lower bridge arm of the first phase half bridge, the lower bridge arm of the second phase half bridge, the upper bridge arm of the third phase half bridge and the upper bridge arm of the half-bridge circuit are controlled to be turned on.

10. A vehicle, characterized in that: The vehicle comprises an integrated system as claimed in any one of claims 1 to 7.

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