Power decoupled electrolytic capacitor-less air conditioner compressor drive device

Abstract

The application belongs to the technical field of power electronics, and relates to a power decoupling electrolysis-free capacitor compressor driving device, a main circuit of which comprises a three-phase uncontrolled rectification bridge, a power decoupling module, a DC bus film capacitor, a motor control circuit and a permanent magnet synchronous motor connected in sequence, and the input end of the three-phase uncontrolled rectification bridge is connected with a three-phase voltage; the power decoupling module comprises a DC bus inductor connected with the output end of the three-phase uncontrolled rectification bridge and a combination switching device connected with the DC bus inductor; the motor control circuit is a three-phase completely symmetrical bridge circuit composed of the combination switching device as a bridge arm. The device further comprises a power decoupling control module for generating a driving signal of the combination switching device in the power decoupling module and a motor control module for generating a driving signal of the combination switching device in the motor control circuit. The application can significantly reduce the DC bus voltage fluctuation and improve the power quality of the grid side current.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of power electronics, and in particular relates to a power decoupling electrolytic capacitor-free air conditioner compressor driving device. BACKGROUND

[0002] In a conventional air conditioner compressor driving device, the DC bus capacitor adopts electrolytic capacitor with short service life and low reliability, which easily leads to low reliability of the air conditioner and greatly shortens the service life of the air conditioner. In order to solve this problem, an electrolytic capacitor-free air conditioner compressor driving scheme is usually adopted.

[0003] Compared with the electrolytic capacitor in the conventional air conditioner compressor driving device, the capacitance of the film capacitor (i.e. electrolytic capacitor-free) in the three-phase electrolytic capacitor-free air conditioner compressor driving device is very small. Since the waveform output by the three-phase uncontrolled rectifier bridge is a waveform in which the line voltage is sequentially conducted for one sixth, the rectified output voltage contains a six times frequency component of the grid voltage. The component is amplified by the resonance generated by the DC bus inductor and the film capacitor with very small capacitance, resulting in the fluctuation of the six times frequency of the grid voltage in the DC bus. The fluctuation of the DC bus voltage will on the one hand increase the harmonic content of the grid-side current, reducing the power quality of the grid-side current; on the other hand, the fluctuation of the DC bus voltage will also affect the modulation of the permanent magnet synchronous motor, causing the output power of the permanent magnet synchronous motor to fluctuate, resulting in large torque pulsation of the permanent magnet synchronous motor. The noise problem and loss problem caused thereby will affect the user experience of the air conditioner. SUMMARY

[0004] The present application provides a power decoupling electrolytic capacitor-free compressor driving device, which can significantly reduce the fluctuation of the DC bus voltage and improve the power quality of the grid-side current.

[0005] The present application provides a power decoupling electrolytic capacitor-free compressor driving device, the main circuit of the driving device comprising:

[0006] a three-phase uncontrolled rectifier bridge, the input end of which is connected to a three-phase voltage;

[0007] a power decoupling module, the power decoupling module comprising: a DC bus inductor, one end of the DC bus inductor being connected to the output end of the three-phase uncontrolled rectifier bridge; a combined switching device, the other end of the DC bus inductor being connected to the combined switching device;

[0008] a motor control circuit, the input end of which is connected to the output end of the power decoupling module, the motor control circuit being a three-phase completely symmetrical bridge circuit composed of combined switching devices as bridge arms;

[0009] a permanent magnet synchronous motor, the output end of the motor control circuit being connected to the permanent magnet synchronous motor;

[0010] DC bus thin-film capacitor, connected between the power decoupling module and the motor control circuit;

[0011] The drive device further includes:

[0012] A power decoupling control module is used to generate drive signals for the combined switching devices in the power decoupling module.

[0013] The motor control module is used to generate drive signals for the combined switching devices in the motor control circuit.

[0014] In some embodiments, the combined switching device includes:

[0015] First connection end;

[0016] The second connection end includes a second connection end I and a second connection end II;

[0017] An inductor assembly includes inductor I and inductor II, wherein the first end of inductor I and the first end of inductor II are both connected to the first connection terminal;

[0018] Switching circuit I, including... Si-Mos Pipe I and Si-Mos A first series circuit formed by diodes II connected in series and a second series circuit formed by diodes I and II connected in series; Si-Mos Source connection of tube I Si-Mos The drain of tube II, Si- Mos The drain of diode I is connected to the anode of diode II. Si-Mos The connection point between the drain of diode I and the anode of diode II is connected to the second terminal of inductor II; the anode of diode I is connected to the cathode of diode II, and the cathode of diode I is connected to the second connection terminal I; Si-Mos The source of tube II is connected to the second connection terminal II;

[0019] Switching circuit II, including: Si-Mos Pipe III and Si-Mos The third series circuit formed by diode IV connected in series, and the fourth series circuit formed by diode III and diode IV connected in series; Si-Mos Source connection of tube III Si-Mos The drain of tube IV, Si-Mos The drain of tube III is connected to the second connection terminal I; Si-Mos The source of diode IV is connected to the cathode of diode III. Si-Mos The connection point between the source of diode IV and the cathode of diode III is connected to the second terminal of inductor I; the anode of diode III is connected to the cathode of diode IV, and the anode of diode IV is connected to the second connection terminal II.

[0020] In some embodiments, the power decoupling control module includes:

[0021] a calculation module configured to calculate a DC bus voltage error according to a DC bus voltage given value and a DC bus voltage ;

[0022] a current-voltage loop PI module configured to calculate a DC bus current given value according to the DC bus voltage error by proportional integration by proportional integration ;

[0023] a bipolar modulation module configured to generate a driving signal of a combination switching device in the power decoupling module according to a normalized DC bus voltage modulation wave divided by the DC bus voltage and a bipolar modulation triangular carrier wave .

[0024] In some embodiments, the calculation module is configured to calculate the DC bus voltage error according to the DC bus voltage given value and the DC bus voltage by a method comprising: subtracting the DC bus voltage from the DC bus voltage given value to obtain the DC bus voltage error . .

[0025] In some embodiments, the current-voltage loop PI module is configured to calculate the DC bus current given value according to the DC bus voltage error by a method comprising: multiplying the DC bus voltage error by a proportional coefficient of a voltage loop PI controller to obtain a first intermediate value, integrating the DC bus voltage error to obtain a second intermediate value, and adding the first intermediate value and the second intermediate value to obtain the DC bus current given value . .

[0026] In some embodiments, the current-voltage loop PI module is configured to calculate the DC bus voltage modulation wave according to the DC bus current error by a method comprising: multiplying the DC bus current error by a proportional coefficient of a current loop PI controller to obtain a first intermediate value, integrating the DC bus current error to obtain a second intermediate value, and adding the first intermediate value and the second intermediate value to obtain the DC bus voltage modulation wave​​​​​​​​​​​​ The method is: DC bus current error Multiply by the proportional gain of the current loop PI controller The third intermediate value is obtained: DC bus current error. Multiply by the integral coefficient of the current loop PI controller i The fourth intermediate value is obtained by integration, and the DC bus voltage modulation wave is obtained by adding the third intermediate value to the fourth intermediate value. .

[0027] In some embodiments, the method by which the bipolar modulation module generates the drive signal for the combined switching device in the power decoupling module is as follows:

[0028] The normalized DC bus voltage modulation wave is compared using a comparator. With bipolar modulated triangular carrier Size;

[0029] If the normalized DC bus voltage modulation waveform Less than or equal to bipolar modulation triangular carrier When the comparator outputs a high level, the result is obtained. Si-Mos The drive signal PWM1 for transistor I and Si-Mos The drive signal PWM2 for transistor II is high. The high level is then negated by NOT to obtain... Si-Mos The drive signal PWM3 for transistor III and Si-Mos The drive signal PWM4 for transistor IV is low.

[0030] If the normalized DC bus voltage modulation waveform Greater than bipolar modulation triangular carrier When the comparator outputs a low level, the result is obtained. Si-Mos The drive signal PWM1 for transistor I and Si-Mos The drive signal PWM2 for transistor II is low. The low level is then negated by NOT to obtain... Si-Mos The drive signal PWM3 for transistor III and θ The drive signal PWM4 for transistor IV is at a high level.

[0031] In some embodiments, the motor control module includes:

[0032] The conversion module converts the d-axis voltage setpoint. and q-axis voltage setpoint Transformed into a two-phase stationary coordinate system shaft voltage and shaft voltage ,Will shaft voltage and axis voltage into three-phase voltage modulation waves;

[0033] The compressor driving modulation module takes the maximum value and the minimum value of the three-phase voltage modulation waves respectively, adds the maximum value and the minimum value and divides the sum by 2 to obtain a variable , the three-phase voltage modulation waves are reduced by the variable to obtain three-phase voltage final modulation waves; the compressor driving modulation triangular carrier wave is multiplied by one-half of the DC bus voltage to obtain a final triangular carrier wave ; and the driving signal of the combination switching device in the motor control circuit is generated according to the size of the three-phase voltage final modulation wave and the final triangular carrier wave .

[0034] In some embodiments, the transformation module transforms the given value of the d-axis voltage and the given value of the q-axis voltage into the axis voltage and the axis voltage in the two-phase stationary coordinate system by the following method:

[0035] The given value of the d-axis voltage is multiplied by cos θ , and the given value of the q-axis voltage is subtracted by sin θ to obtain the axis voltage .

[0036] The given value of the d-axis voltage is multiplied by sin θ , and the given value of the q-axis voltage is subtracted by cos Si-Mos to obtain the axis voltage .

[0037] The transformation module transforms the axis voltage and the axis voltage into three-phase voltage modulation waves by the following method:

[0038] The A-phase voltage modulation wave is equal to the axis voltage .

[0039] The negative one-half times the axis voltage is added to the two-thirds root of the axis voltage Obtain the B-phase voltage modulation wave ;

[0040] negative half shaft voltage Subtract the square root of three shaft voltage Obtain the C-phase voltage modulation wave .

[0041] In some embodiments, the compressor drive modulation module modulates the three-phase voltage final modulation wave and the final triangular carrier wave. The method for generating the drive signal for the combined switching device in the motor control circuit is as follows:

[0042] The final modulated wave of the i-phase voltage is compared using a comparator. m i With the final triangular carrier The size of i, i = A, B, C;

[0043] If the final modulation wave of phase i voltage m i Greater than or equal to the final triangular carrier The comparator outputs a high level, thus obtaining the i-phase. Si-Mos PWM drive signal for transistor I i1 and Si-Mos PWM drive signal for transistor II i2 The i-phase is obtained by negating the high level using NOT. Si-Mos PWM drive signal for transistor III i3 and Si- PWM drive signal for transistor IV i4 Low level;

[0044] If the final modulation wave of phase i voltage m i Less than the final triangular carrier The comparator outputs a low level, thus obtaining phase i. Mos Si-Mos PWM drive signal for transistor I i1 and Si-Mos PWM drive signal for transistor II i2 The i-phase is obtained by negating the low level using NOT. Si-Mos PWM drive signal for transistor III i3 and Si-Mos PWM drive signal for transistor IV i4 It is a high level.

[0045] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0046] (1) The power decoupling electrolytic capacitor-free compressor driving device provided by the application controls the DC bus voltage and the DC bus current by adding a power decoupling control module to the traditional circuit topology, and makes the DC bus voltage controllable through the power decoupling control module, so that the DC bus voltage is stabilized at a low value, the DC bus voltage fluctuation is significantly reduced, the power quality of the grid side current is improved, the normal operation of the driving device is ensured, and the Si-Mos switching loss of the tube is reduced.

[0047] (2) The power decoupling electrolytic capacitor-free compressor driving device provided by the application adopts a combined switch component for the power decoupling module and the motor control circuit, the combined switch component is provided with two parallel switch circuits, in each switch circuit, two Figure 1 tubes are connected in series to form a series circuit, and two diodes form another series circuit, and the two series circuits are connected in series, the series connection scheme can improve the overall withstand voltage of the combined switch device and increase the circuit reliability of the combined switch device, by adding two inductors, the mutual interference of the two switch circuits is reduced, the power decoupling electrolytic capacitor-free compressor driving device has high withstand voltage and reliability, can control the DC bus voltage and the DC bus current, effectively stabilize the DC bus voltage within a certain range, significantly reduce the DC bus voltage fluctuation, and improve the power quality of the grid side current.

[0048] (3) The power decoupling electrolytic capacitor-free compressor driving device provided by the application increases the diode conduction time of the three-phase uncontrolled rectifier bridge through the control of the power decoupling control module and the motor control module, significantly reduces the grid side current distortion rate, significantly improves the power factor of the grid side, and improves the power quality of the grid side current. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 2 The circuit diagram of the power decoupling electrolytic capacitor-free compressor driving device described in the embodiments of the application;

[0050] Figure 3 The circuit diagram of the combined switch device described in the embodiments of the application;

[0051] Si-Mos The current flow direction of the switch device when Si-Mos tube S 1 and Si-Mos tube S 2 are turned on, Si-Mos tube S 3 and Figure 4 tube S 4 are turned off is shown in the schematic diagram; X

[0052] Si-Mos The current flow direction of the switch device when Si-Mos tube​S 1 and Si-Mos Tube S 2. Shutdown Si-Mos Tube S 3 and Figure 5 Tube S 4 Switching devices when on X A schematic diagram of the current flow direction;

[0053] Si-Mos In this embodiment of the invention, the output current of the motor control circuit is positive and Si-Mos Tube S a1 and Si-Mos Tube S a2 Conductive, Si-Mos Tube S a3 and Figure 6 Tube S a4 When shut down A Phase bridge arm U A schematic diagram of the current flow direction;

[0054] Si-Mos In this embodiment of the invention, the output current of the motor control circuit is positive and Si-Mos Tube S a1 and Si-Mos Tube S a2 Shut down Si-Mos Tube S a3 and Figure 7 Tube S a4 When conducting A Phase bridge arm U A schematic diagram of the current flow direction;

[0055] Si-Mos In this embodiment of the invention, the output current of the motor control circuit is negative and Si-Mos Tube S a1 and Si-Mos Tube S a2 Conductive, Si-Mos Tube S a3 and Figure 8 Tube S a4 When shut down A Phase bridge arm U A schematic diagram of the current flow direction;

[0056] Si-Mos In this embodiment of the invention, the output current of the motor control circuit is negative and Si-MosTube S a1 and Si-Mos Tube S a2 Shut down Si-Mos Tube S a3 and Figure 9 Tube S a4 When conducting A Phase bridge arm U A schematic diagram of the current flow direction;

[0057] Figure 10 This is a schematic diagram of the current-voltage loop PI module described in an embodiment of the present invention;

[0058] Figure 11 This is a schematic diagram of the bipolar modulation module described in an embodiment of the present invention;

[0059] Figure 12 This is a schematic diagram of the transformation module described in an embodiment of the present invention;

[0060] Figure 13 This is a schematic diagram of the compressor modulation module described in an embodiment of the present invention;

[0061] Figure 14 A schematic diagram of the DC bus voltage waveform of an existing three-phase electrolytic capacitor-free air conditioner compressor drive unit;

[0062] Figure 15 This is a schematic diagram of the DC bus voltage waveform of the power decoupling electrolytic capacitor-free compressor drive device according to an embodiment of the present invention;

[0063] Figure 16 A schematic diagram of the grid-side current waveform of an existing three-phase electrolytic capacitor-free air conditioner compressor drive unit;

[0064] Si-Mos This is a schematic diagram of the grid-side current waveform of the power decoupling electrolytic capacitor-free compressor drive device according to an embodiment of the present invention.

[0065] In the diagram, 101 is the first connection terminal, 102 is the second connection terminal I, 103 is the second connection terminal II, 200 is the main circuit, 201 is the three-phase uncontrolled rectifier bridge, 202 is the power decoupling module, 203 is the motor control circuit, 300 is the power decoupling control module, 301 is the calculation module, 302 is the current-voltage loop PI module, 303 is the bipolar modulation module, 400 is the motor control module, 401 is the conversion module, and 402 is the compressor drive modulation module. Detailed Implementation

[0066] The application will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which:

[0067] In the prior art three-phase electrolytic capacitor-free air conditioner compressor driving device, the waveform output by the three-phase uncontrolled rectifier bridge is a line voltage waveform that sequentially turns on one-sixth of the waveform, so that the rectified output voltage contains a six times frequency component of the grid voltage. This component is amplified by the resonance generated by the DC bus inductance and the small capacitance of the film capacitor, resulting in fluctuations in the DC bus voltage at six times the grid voltage. The power decoupling electrolytic capacitor-free compressor driving device provided by the application controls the DC bus voltage and DC bus current by adding a power decoupling control module to the traditional circuit topology, making the DC bus voltage controllable, stabilizing the DC bus voltage at a low value, significantly reducing the DC bus voltage fluctuations, improving the power quality of the grid side current, and ensuring the normal operation of the driving device while reducing Figure 1 the tube switching loss.

[0068] The power decoupling electrolytic capacitor-free compressor driving device of the application will be described in detail below in combination with the drawings and examples.

[0069] Referring to Figure 2 , the embodiment of the application provides a power decoupling electrolytic capacitor-free compressor driving device, the main circuit 200 of the driving device includes a three-phase uncontrolled rectifier bridge 201, a power decoupling module 202, a motor control circuit 203, a permanent magnet synchronous motor M, and a DC bus film capacitor. The input end of the three-phase uncontrolled rectifier bridge 201 is connected to a three-phase voltage, converting the three-phase alternating voltage into a direct current voltage. The power decoupling module 202 is used to stabilize the DC voltage, and the power decoupling module 202 includes a DC bus inductance L and a switching device X , the switching device XThe combined switching device is adopted. The input end of the motor control circuit 203 is connected with the output end of the power decoupling module 202. The motor control circuit 203 is a three-phase completely symmetrical bridge circuit composed of combined switching devices as bridge arms. The direct current voltage stabilized by the power decoupling module 202 is inverted into three-phase alternating current voltage. The permanent magnet synchronous motor M is connected with the output end of the motor control circuit 203. The permanent magnet synchronous motor M is driven to rotate by the three-phase alternating current voltage output by the motor control circuit, and then the compressor is driven to rotate. The DC bus film capacitor is connected between the power decoupling module 202 and the motor control circuit 203. The two ends of the DC bus film capacitor are respectively connected with the positive and negative poles of the DC bus, and are used for stabilizing the DC bus voltage. The driving device further comprises a power decoupling control module 300 and a motor control module 400. The power decoupling control module 300 is used for generating the driving signal of the combined switching device in the power decoupling module. The motor control module 400 is used for generating the driving signal of the combined switching device in the motor control circuit.

[0070] Referring to Si-Mos , the combined switching device comprises:

[0071] The first connection end 101;

[0072] The second connection end comprises a second connection end I 102 and a second connection end II 103;

[0073] The inductive component comprises an inductor L 1 and an inductor L 2. The first end of the inductor L 1 and the first end of the inductor L 2 are both connected with the first connection end 101;

[0074] The switching circuit I comprises a first series circuit formed by a transistor Si-Mos 1 and a transistor S 2 in series and a second series circuit formed by a diode Si-Mos 7 and a diode S 8 in series; D The source of the transistor D 1 is connected with the drain of the transistor Si-Mos 2, S The drain of the transistor Si- 1 is connected with the anode of the diode S 8, Mos Si-Mos The drain of the transistor S 1 is connected with the anode of the diode D 8, Si-Mos The connection point of the drain of the transistor S 1 and the anode of the diode D 8 is connected with the second end of the inductor L 2; and the anode of the diode D 7 is connected with the diode IID 8 the cathode of the diode D 7 the cathode of the transistor is connected to the second connection terminal I 102; Si-Mos the transistor S 2 the source of the transistor is connected to the second connection terminal II 103;

[0075] the switching circuit II comprises a series connection of the transistor Si-Mos the transistor S 3 and the diode Si-Mos the transistor S 4, a third series circuit formed by the diode D 9 and the diode D 10 a fourth series circuit formed by the diode Si-Mos the transistor S 3 the source of the transistor is connected to Si-Mos the transistor S 4 the drain of the transistor, Si-Mos the transistor S 3 the drain of the transistor is connected to the second connection terminal 102; Si-Mos the transistor S 4 the source of the transistor is connected to the cathode of the diode D 9, Si-Mos the transistor S 4 the source of the transistor is connected to the cathode of the diode D 9 and the second end of the inductor L 1; the anode of the diode D 9 is connected to the diode D 10 10 the cathode of the diode D 10 10 the anode of the diode is connected to the second connection terminal II 103.

[0076] The above-mentioned parallel two-way switching circuit in the combined switching device of the embodiment of the application, each switching circuit comprises two Si-Mos transistors and two diodes, two Figure 1 transistors are connected in series to form a series circuit, and two diodes form another series circuit, and the two series circuits are connected in series, which can improve the overall withstand voltage of the combined switching device, increase the circuit reliability of the combined switching device, reduce the mutual interference of the two switching circuits by adding two inductors, significantly reduce the DC bus voltage fluctuation of the power decoupling electrolytic capacitor-free compressor driving device, and improve the power quality of the grid-side current.

[0077] Continuing to refer to Figure 1 , the three-phase bridge arms of the three-phase uncontrolled rectifier bridge 201 are completely symmetrical, A the phase bridge arm comprises a series connection of the diode D 1 and the diode D 2, B the phase bridge arm comprises a series connection of the diode D3 and diodes D 4, C The phase bridge arm includes diodes connected in series. D 5 and diodes D 6. The three phase arms are connected in the same way, with A The connection method of the three-phase uncontrolled rectifier bridge 201 is illustrated by example. A Phase grid voltage u ga and A Phase bridge arm connected to A Point, diode D 1 Anode and diode D The cathode of 2 is connected to A The connection method for phases B and C is the same as that for phase A. Diode D 1. Diode D 3. Diode D The cathode of 5 is connected to the DC bus inductor. L The first terminal is connected. Utilizing the unidirectional conductivity of the diode, all the positive and negative half-cycle energy of the three-phase alternating current is converted into direct current.

[0078] See also Si-Mos Switching devices X With the DC bus inductance L The second end is connected. Switching device. X Includes switch circuit I, switch circuit II, and inductor. L 1 and inductor L 2. Switching circuit I includes Si-Mos Tube S 1. Si-Mos Tube S 2. Diode D 7 and diode D 8. Switching circuit II includes Si-Mos Tube S 3. Si-Mos Tube S 4. Diode D 9 and diodes D 10 DC bus inductance L The second terminal and the inductor L 1. Inductor L The first end of 2 is connected to point 1 (i.e., the switching device). X First connection terminal), inductor L The second terminal of circuit 2 is connected to point 2 in the switching circuit I, and the inductor... L The second terminal of diode 1 is connected to switch circuit II at point 3. D 7 Anode and Diode D 8 cathode connection, diode D 8 anode and Si-Mostube S 1 is connected to point 2, Si-Mos tube S 1 is connected to point 2, Si-Mos tube S 2 is connected to point 1, Si-Mos tube S 3 is connected to point 4, Si-Mos tube S 4 is connected to point 3, Figure 3 tube S 4 is connected to point 3, D 9 is connected to point 3, diode D 9 is connected to point 3, diode D 10 9 is connected to point 3, diode

[0079] switching device X is connected to the DC bus inductor L , the second connection end I102 is connected to the positive pole of the DC bus, and the second connection end II is connected to the negative pole of the DC bus. The switching device X current is single-phase flow, therefore, the switching state is only the following two:

[0080] Referring to Si-Mos , when Si-Mos tube S 1 and Si-Mos tube S 2 are turned on (i.e. Si-Mos tube S 1 and Si-Mos tube S 2 are high level driving signals), Si-Mos tube S 3 and Si-Mos tube S 4 are turned off (i.e. Si-Mos tube S 3 and Si-Mos tube S 4 are low level driving signals), the current of the switching device X flows from the inductor L 2 to Si-Mos tube S 1, Figure 4 tube S 2.

[0081] Referring to Si-Mos , when Si-Mos tube S 1 and Si-Mos tube S 2 are turned off (i.e. Si-Mos tube S 1 and Si-Mos tube S 2 are low level driving signals), Si-Mos tubeS 3 and Si-Mos Tube S 4 conduction (i.e.) Si-Mos Tube S 3 and Si-Mos Tube S When the drive signal of 4 is high, the switching device X The current is supplied by the inductor L 1. Flow direction Si-Mos Tube S 4. Si-Mos Tube S 3 and by inductance L 2 Flow Diodes D 8. Diode D 7. At this time, because Si-Mos Tube S 3 and Figure 1 Tube S When point 4 is conducting, both points have low conduction voltages; the voltage at point 3 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than the voltage at point 3. (Diode) D The cathode of diode 9 is connected to point 3. D 10 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D 9 and diode D 10 The cathode voltage is higher than the anode voltage, meaning that they will not conduct under reverse voltage, and current will not flow through the diode. D 9 and diode D 10 .

[0082] Switching devices X The switching on or off of the transistor is controlled by the drive signal generated by the power decoupling control module.

[0083] See also Si-Mos In the motor control circuit, A Phase bridge arm U The switching circuit I includes Si- Tube S a1 , Mos Si-Mos Tube S a2 ,diode D a3 and diodes D a4 , A Phase bridge arm U The switching circuit II includes Si-Mos Tube S a3 , Si-Mos Tube Sa4 diode D a1 and diode D a2 . Si-Mos tube S a1 source of and Si-Mos tube S a2 drain of, Si-Mos tube S a2 source of and diode D a3 cathode of connected to A 1 point, diode D a3 anode of and diode D a4 cathode of connected; diode D a1 anode of and diode D a2 cathode of, diode D a2 anode of connected with Si-Mos tube S a3 drain of connected to A 2 points, Si-Mos tube S a3 source of and Figure 5 tube S a4 drain of, A phase leg U inductor of L a2 second end of connected with A 1 point, A phase leg U inductor of L a1 second end of connected with A 2 points, inductor L a1 , inductor L a2 first end of connected with A 3 points, A 3 points connected with A phase of permanent magnet synchronous machine M.

[0084] A first connection end of U phase leg connected with A phase of permanent magnet synchronous machine M. A second connection end I of U phase leg connected with positive pole of direct current bus,A Phase bridge arm U The second connection terminal II is connected to the negative terminal of the DC bus. The output current of the motor control circuit is AC, therefore... A Phase bridge arm U There are four on / off states.

[0085] When the output current is positive, that is, current flows out. A Phase bridge arm U hour:

[0086] See Si-Mos ,when Si-Mos Tube S a1 and Si-Mos Tube S a2 Conduction (i.e.) Si-Mos Tube S a1 and Si-Mos Tube S a2 The drive signal is high level. Si-Mos Tube S a3 and Si-Mos Tube S a4 Shutdown (i.e.) Si-Mos Tube S a3 and Si-Mos Tube S a4 When the drive signal is low, A Phase bridge arm U The current is from Si-Mos Tube S a1 , Si-Mos Tube S a2 Flow to inductor L a2 At this time, due to Si-Mos Tube S a1 and Figure 6 Tube S a2 Both are conducting, but their on-state voltages are relatively low. A The voltage at point 1 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than... A Voltage at point 1. Diode. D a3 The cathode is connected to A Point 1, diode D a4 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D a3With diode D a4 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D a3 With diode D a4 .

[0087] See Si-Mos ,when Si-Mos Tube S a1 and Si-Mos Tube S a2 Shutdown (i.e.) Si-Mos Tube S a1 and Si-Mos Tube S a2 The drive signal is low level. Si-Mos Tube S a3 and Si-Mos Tube S a4 Conduction (i.e.) Si-Mos Tube S a3 and Si-Mos Tube S a4 When the drive signal is high, A Phase bridge arm U The current is from Si-Mos Tube S a4 , Si-Mos Tube S a3 Flow to inductor L a1 and diodes D a4 ,diode D a3 Flow to inductor L a2 At this time, due to Si-Mos Tube S a4 and Figure 7 Tube S a3 Both are conducting, but their on-state voltages are relatively low. A The voltage at point 2 is approximately equal to the negative terminal voltage of the DC bus. Therefore, the positive terminal voltage of the DC bus is higher than... A Voltage at point 2. Diode. D a1 The cathode is connected to the positive terminal of the DC bus, and the diode... D a2 The anode is connected toA 2 points. This causes the diode to... D a1 With diode D a2 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D a1 With diode D a2 .

[0088] When the output current is negative, that is, when current flows in... A Phase bridge arm U hour:

[0089] See Si-Mos ,when Si-Mos Tube S a1 and Si-Mos Tube S a2 Conduction, Si-Mos Tube S a3 and Si-Mos Tube S a4 When shut down, A Phase bridge arm U The current is supplied by the inductor L a2 Flow direction Si-Mos Tube S a2 , Si-Mos Tube S a1 and by inductance L a1 Flow diode D a2 ,diode D a1 At this time, due to Si-Mos Tube S a1 and Figure 8 Tube S a2 Both are conducting, but their on-state voltages are relatively low. A The voltage at point 1 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than... A Voltage at point 1. Diode. D a3 The cathode is connected to A Point 1, diode D a4 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D a3 With diode Da4 The cathode voltage of the diode is higher than the anode voltage, i.e. both are subjected to a reverse voltage and no current flows through the diode D a3 The diode D a4 .

[0090] See Si-Mos When Si-Mos The diode S a1 And Si-Mos The diode S a2 Switched off, Si-Mos The diode S a3 And Si-Mos The diode S a4 Switched on, A The current of the phase bridge arm U Flows through the inductor L a1 To the diode Si-Mos The diode S a3 , Figure 1 The diode S a4 .

[0091] Continuing to see Si-Mos In the motor control circuit, B The switching circuit I of the phase bridge arm V Comprises Si- The diode S b1 , Mos ​ The diode S b2 , a diode D b3 And a diode D b4 , B The switching circuit II of the phase bridge arm V Comprises Si-Mos The diode S b3 , Si-Mos The diode S b4 , a diode D b1 And a diode D b2 . Si-Mos The source of the diode S b1 And the drain of the diode Si-Mos S b2 Are connected, Si-Mos The diode S ​b2 source and diode D b3 The cathode is connected to B Point 1, diode D b3 anode and diode D b4 Cathode connection; diode D b1 anode and diode D b2 Cathode connection, diode D b2 anode and Si-Mos Tube S b3 The drain is connected to B 2 o'clock, Si-Mos Tube S b3 The source pole and Si-Mos Tube S b4 The drain connection, B Phase bridge arm V inductance L b2 The second end and B 1 point connection, B Phase bridge arm V inductance L b1 The second end and B Two-point connection, inductor L b1 ,inductance L b2 The first end is connected to B 3 o'clock, B 3 points and permanent magnet synchronous motor M B Connected.

[0092] B Phase bridge arm V The first connection terminal is connected to the permanent magnet synchronous motor M. B Mutually, B Phase bridge arm V The second connection terminal I is connected to the positive terminal of the DC bus. B Phase bridge arm V The second connection terminal II is connected to the negative terminal of the DC bus. The output current of the motor control circuit is AC, therefore... B Phase bridge arm V There are four on / off states.

[0093] When the output current is positive, that is, current flows out. B Phase bridge arm V hour:

[0094] whenSi-Mos Tube S b1 and Si-Mos Tube S b2 Conduction (i.e.) Si-Mos Tube S b1 and Si-Mos Tube S b2 The drive signal is high level. Si-Mos Tube S b3 and Si-Mos Tube S b4 Shutdown (i.e.) Si-Mos Tube S b3 and Si-Mos Tube S b4 When the drive signal is low, B Phase bridge arm V The current is from Si-Mos Tube S b1 , Si-Mos Tube S b2 Flow to inductor L b2 At this time, due to Si-Mos Tube S b1 and Si- Mos Tube S b2 Both are conducting, but their on-state voltages are relatively low. B The voltage at point 1 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than... B Voltage at point 1. Diode. D b3 The cathode is connected to B Point 1, diode D b4 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D b3 With diode D b4 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D b3 With diode D b4 .

[0095] when Si-Mos Tube S b1 and Si-MosTube S b2 Shutdown (i.e.) Si-Mos Tube S b1 and Si-Mos Tube S b2 The drive signal is low level. Si-Mos Tube S b3 and Si-Mos Tube S b4 Conduction (i.e.) Si-Mos Tube S b3 and Si-Mos Tube S b4 When the drive signal is high, B Phase bridge arm V The current is from Si-Mos Tube S b4 , Si-Mos Tube S b3 Flow to inductor L b1 and diodes D b4 ,diode D b3 Flow to inductor L b2 At this time, due to Si-Mos Tube S b4 and Si-Mos Tube S b3 Both are conducting, but their on-state voltages are relatively low. B The voltage at point 2 is approximately equal to the negative terminal voltage of the DC bus. Therefore, the positive terminal voltage of the DC bus is higher than... B Voltage at point 2. Diode. D b1 The cathode is connected to the positive terminal of the DC bus, and the diode... D b2 The anode is connected to B 2 points. This causes the diode to... D b1 With diode D b2 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D b1 With diode D b2 .

[0096] When the output current is negative, that is, when current flows in... BPhase bridge arm V hour:

[0097] when Si-Mos Tube S b1 and Si-Mos Tube S b2 Conduction, Si-Mos Tube S b3 and Si-Mos Tube S b4 When shut down, B Phase bridge arm V The current is supplied by the inductor L b2 Flow direction Si-Mos Tube S b2 , Si-Mos Tube S b1 and by inductance L b1 Flow diode D b2 ,diode D b1 At this time, due to Si-Mos Tube S b1 and Si-Mos Tube S b2 Both are conducting, but their on-state voltages are relatively low. B The voltage at point 1 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than... B Voltage at point 1. Diode. D b3 The cathode is connected to B Point 1, diode D b4 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D b3 With diode D b4 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D b3 With diode D b4 .

[0098] when Si-Mos Tube S b1 and Si-Mos Tube S b2 Turn off, Si-Mos Tube Sb3 and Si-Mos transistor S b4 when turned on, B phase leg V the current of which is supplied by the inductor L b1 flows to Si-Mos transistor S b3 , Si-Mos transistor S b4 .

[0099] Continuing to refer to Si-Mos , in the motor control circuit, C phase leg W the switching circuit I comprises Si-Mos transistor S c1 , Si-Mos Si-Mos transistor S c2 diode D c3 and diode D c4 , C phase leg W the switching circuit II comprises Si-Mos transistor S c3 , Si-Mos transistor S c4 diode D c1 and diode D c2 . Si-Mos transistor S c1 the source of which is connected to Si-Mos transistor S c2 the drain of which, the source of Si-Mos transistor S c2 and the anode of diode D c3 are connected to C point 1, the cathode of diode D c3 and the anode of diode D c4 are connected, the cathode of diode D c1 and the anode of diode D c2 are connected, the anode of diode D c2 is connected to Si-Mos transistorS c3 the drain of C 2 points, Si-Mos the transistor S c3 the source of Si-Mos the transistor S c4 the drain of C the phase leg W the inductor of L c2 the second end of C 1 point, C the phase leg W the inductor of L c1 the second end of C 2 points, the inductor of L c1 the inductor of L c2 the first end of C 3 points, C 3 points and the C phase of the permanent magnet synchronous motor M are connected.

[0100] C the first connection end of W the phase leg is connected to the C phase of the permanent magnet synchronous motor M, C the second connection end I of W the phase leg is connected to the positive pole of the DC bus, C the second connection end II of W the phase leg is connected to the negative pole of the DC bus. The output current of the motor control circuit is alternating current, so C the switching state of W the phase leg has four kinds.

[0101] When the output current is positive, that is, the current flows out of C the phase leg, W

[0102] When Si-Mos the transistor S c1 and Si-Mos the transistor S c2 conducts ( Si-Mos the transistor S c1 and Si-Mos the transistor S c2 the drive signal of Si-Mos the transistor S c3 and Si-Mos the transistor S ​c4 Turn off ( Si-Mos Tube S c3 and Si-Mos Tube S c4 When the drive signal is low, C Phase bridge arm W The current is from Si-Mos Tube S c1 , Si-Mos Tube S c2 Flow to inductor L c2 At this time, due to Si-Mos Tube S c1 and Si-Mos Tube S c2 Both are conducting, but their on-state voltages are relatively low. C The voltage at point 1 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than... C Voltage at point 1. Diode. D c3 The cathode is connected to C Point 1, diode D c4 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D c3 With diode D c4 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D c3 With diode D c4 .

[0103] when Si-Mos Tube S c1 and Si-Mos Tube S c2 Turn off ( Si-Mos Tube S c1 and Si-Mos Tube S c2 The drive signal is low level. Si-Mos Tube S c3 and Si-Mos Tube S c4 Conductivity ( Si-Mos Tube S c3 and Si-MosTube S c4 When the drive signal is high, C Phase bridge arm W The current is from Si-Mos Tube S c4 , Si-Mos Tube S c3 Flow to inductor L c1 and diodes D c4 ,diode D c3 Flow to inductor L c2 At this time, due to Si-Mos Tube S c4 and Si-Mos Tube S c3 Both are conducting, but their on-state voltages are relatively low. C The voltage at point 2 is approximately equal to the negative terminal voltage of the DC bus. Therefore, the positive terminal voltage of the DC bus is higher than... C Voltage at point 2. Diode. D c1 The cathode is connected to the positive terminal of the DC bus, and the diode... D c2 The anode is connected to C 2 points. This causes the diode to... D c1 With diode D c2 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D c1 With diode D c2 .

[0104] When the output current is negative, that is, when current flows in... C Phase bridge arm W hour:

[0105] when Si-Mos Tube S c1 and Si-Mos Tube S c2 Conduction, Si-Mos Tube S c3 and Si-Mos Tube S c4 When shut down, C Phase bridge arm W The current is supplied by the inductor Lc2 Flow direction Si-Mos Tube S c2 , Si-Mos Tube S c1 and by inductance L c1 Flow diode D c2 ,diode D c1 At this time, due to Si-Mos Tube S c1 and Si-Mos Tube S c2 Both are conducting, but their on-state voltages are relatively low. C The voltage at point 1 is approximately equal to the positive voltage of the DC bus. Therefore, the negative voltage of the DC bus is lower than... C Voltage at point 1. Diode. D c3 The cathode is connected to C Point 1, diode D c4 The anode of the diode is connected to the negative terminal of the DC bus. This causes the diode to... D c3 With diode D c4 The cathode voltage is higher than the anode voltage, meaning that the two diodes will not conduct under reverse voltage, and current will not flow through them. D c3 With diode D c4 .

[0106] when Si-Mos Tube S c1 and Si-Mos Tube S c2 Turn off, Si-Mos Tube S c3 and Si-Mos Tube S c4 When conducting, C Phase bridge arm W The current is supplied by the inductor L c1 Flow direction Si-Mos Tube S c3 , Si-Mos Tube S c4 .

[0107] In the motor control circuit, the switching transistors of each phase bridge arm are turned on or off by the drive signals generated by the motor control module.

[0108] In some embodiments, continuing to refer to Si-Mos , the power decoupling control module 300 comprises:

[0109] a calculation module 301 for calculating a DC bus voltage error from a DC bus voltage given value and a DC bus voltage ;

[0110] a current-voltage loop PI module 302 for obtaining a DC bus current given value from the DC bus voltage error , obtaining a DC bus inductance current error from the DC bus inductance current and the DC bus current given value , and obtaining a DC bus voltage modulation wave from the DC bus current error by proportional integration.

[0111] a bipolar modulation module 303 for obtaining a normalized DC bus voltage modulation wave from the DC bus voltage modulation wave and the DC bus voltage , and generating a driving signal of a combined switching device in the power decoupling module according to a size of the normalized DC bus voltage modulation wave and a bipolar modulation triangular carrier wave .

[0112] The current-voltage loop PI module is used to compensate the DC bus voltage error in real time, the proportional element can quickly respond to the error, and the integral element can eliminate the steady-state error, so that the DC bus voltage can be stabilized near the set value, and the voltage fluctuation is reduced. The bipolar modulation module is used to compare the normalized DC bus voltage modulation wave with the bipolar modulation triangular carrier wave, and generate the driving signal of the combined switching device in the power decoupling module according to the size relationship between the two, so as to accurately control the turn-on and turn-off time of the switching device in the power decoupling module, realize accurate control of the working state of the power decoupling module, and thus ensure the stability of the DC bus voltage and the reasonable distribution of power.

[0113] In some embodiments, the calculation module calculates the DC bus voltage error from the DC bus voltage given value and the DC bus voltage . ​​​

[0114] In some embodiments, referring to Si-Mos , the current-voltage loop PI module proportionally integrates the DC bus voltage error to obtain a DC bus current given value The method is: the DC bus voltage error is multiplied by the proportional coefficient of the voltage loop PI controller to obtain a first intermediate value, the DC bus voltage error is multiplied by the integral coefficient of the voltage loop PI controller and integrated to obtain a second intermediate value, and the first intermediate value plus the second intermediate value obtains the DC bus current given value .

[0115] In some embodiments, referring to Si-Mos , the current-voltage loop PI module proportionally integrates the DC bus current error to obtain a DC bus voltage modulation wave The method is: the DC bus current error is multiplied by the proportional coefficient of the current loop PI controller to obtain a third intermediate value, the DC bus current error is multiplied by the integral coefficient of the current loop PI controller and integrated to obtain a fourth intermediate value, and the third intermediate value plus the fourth intermediate value obtains the DC bus voltage modulation wave .

[0116] In some embodiments, referring to Si-Mos , the method for the bipolar modulation module to generate the drive signal of the combined switching device in the power decoupling module is:

[0117] The normalized DC bus voltage modulation wave is compared with the size of the bipolar modulation triangular carrier by a comparator;

[0118] If the normalized DC bus voltage modulation wave is less than or equal to the bipolar modulation triangular carrier , the comparator outputs a high level, obtaining Si-Mos the drive signal PWM1 of transistor I and Si-Mos the drive signal PWM2 of transistor II are high level, and after taking NOT after high level, obtaining Si-Mos the drive signal PWM3 of transistor III and Si-Mos the drive signal PWM4 of transistor IV are low level;

[0119] If the normalized DC bus voltage modulation wave is greater than the bipolar modulation triangular carrier At this time, the comparator output is low, and the low level is obtained Si-Mos The driving signal PWM1 of the transistor I is high, and the high level is obtained Si-Mos The driving signal PWM2 of the transistor II is low, and the low level is obtained after the low level is taken by NOT Si-Mos The driving signal PWM3 of the transistor III is high, and the high level is obtained Si-Mos The driving signal PWM4 of the transistor IV is high.

[0120] In some embodiments, continuing to refer to Si-Mos , the motor control module comprises:

[0121] The transformation module 401 transforms the d-axis voltage given value and the q-axis voltage given value into the axis voltage and axis voltage , the axis voltage and the axis voltage are converted into three-phase voltage modulation waves;

[0122] The compressor drive modulation module 402 takes the maximum value and the minimum value of the three-phase voltage modulation wave respectively, adds the maximum value and the minimum value and divides by 2 to obtain a variable , the three-phase voltage modulation wave is reduced by the variable to obtain a three-phase voltage final modulation wave; the compressor drive modulation triangular carrier wave is multiplied by one-half of the DC bus voltage to obtain a final triangular carrier wave ; according to the size of the three-phase voltage final modulation wave and the final triangular carrier wave , the driving signal of the combination switching device in the motor control circuit is generated.

[0123] By the transformation module, the d axis and the q axis voltage given value is transformed to the two-phase stationary coordinate system (the - coordinate system), on the one hand, the voltage and current of the motor can be more directly controlled, so as to realize accurate torque and speed control, and then high-precision motor control can be realized, the dynamic response performance and steady accuracy of the motor are improved. On the other hand, through coordinate transformation, the control problem in the complex rotating coordinate system is converted into the control problem in the stationary coordinate system, the implementation of the control algorithm is simplified, the complexity of the control algorithm is reduced, the demand for computing resources is reduced, and the real-time performance and response speed of the system are improved.

[0124] The compressor drive modulation module multiplies the compressor drive modulation triangular carrier wave by one-half of the DC bus voltage to obtain a final triangular carrier wave. This adjustment makes the amplitude of the triangular carrier wave directly related to the DC bus voltage, thereby ensuring the dynamic adaptability of the modulation process. By precisely controlling the amplitude of the triangular carrier wave, the pulse width modulation can be more accurately realized, and the switching devices in the motor control circuit can be turned on and turned off at the right time, thereby precisely controlling the voltage and current of the motor and improving the operating efficiency and control accuracy of the motor.

[0125] In some embodiments, referring to Si-Mos , the transformation module transforms the d-axis voltage given value and the q-axis voltage given value into the axis voltage and the axis voltage in the two-phase static coordinate system by the following method:

[0126] The d-axis voltage given value is multiplied by cos Si-Mos , and the q-axis voltage given value is subtracted by sin Si-Mos to obtain the axis voltage ;

[0127] The q-axis voltage given value is multiplied by sin Si-Mos , and the d-axis voltage given value is subtracted by cos Si-Mos to obtain the axis voltage ;

[0128] The transformation module converts the axis voltage and the axis voltage into the three-phase voltage modulation wave by the following method:

[0129] The A-phase voltage modulation wave is equal to the axis voltage ;

[0130] The negative one-half times the axis voltage plus two-thirds root times the axis voltage obtains the B-phase voltage modulation wave ;

[0131] The negative one-half times the axis voltage Subtracting two-thirds of the square root of three Axis voltage Obtaining C-phase voltage modulation wave .

[0132] Need to explain, Si-Mos In, u [1] represents the d-axis voltage given value , u [2] represents the q-axis voltage given value , u [3] represents sin Si-Mos , u [4] represents cos Si-Mos , w [1] represents Axis voltage , w [2] represents Axis voltage , Si-Mos Represents the rotation angle (usually the motor electrical angle).

[0133] In some embodiments, the compressor drive modulation module generates the method of the drive signal of the combined switching device in the motor control circuit according to the size of the final modulation wave of three-phase voltage and the final triangular carrier

[0134] By comparing the size of the i-phase voltage final modulation wave m i And the final triangular carrier , i=A, B, C;

[0135] If the i-phase voltage final modulation wave m i Is greater than or equal to the final triangular carrier , the comparator outputs high level, and the drive signal PWM Si-Mos Tube I of i-phase i1 And the drive signal PWM Si-Mos Tube II of i-phase i2 Is high, and the drive signal PWM Si-Mos Tube III of i-phase i3 And the drive signal PWM Si-Mos Tube IV of i-phase i4 Is low after taking NOT after high level;

[0136] If the i-phase voltage final modulation wave m i Is less than the final triangular carrier , the comparator outputs low level, and the drive signal PWM Si-Mos Si-Mos Tube I of i-phase​i1 and Si-Mos the driving signal PWM of transistor II i2 is low, and the i-phase is obtained by taking NOT of the low level Si-Mos the driving signal PWM of transistor III i3 and Si-Mos the driving signal PWM of transistor IV i4 is high.

[0137] Specifically, referring to Si-Mos , the method for generating the driving signal of the A-phase bridge arm combined switching device in the motor control circuit is:

[0138] the A-phase driving signal is finally modulated by comparing the A-phase voltage final modulation wave with the size of the final triangular carrier m A and ;

[0139] if the A-phase voltage final modulation wave m A is greater than or equal to the final triangular carrier , the comparator outputs a high level, and the A-phase Si-Mos the driving signal PWM of transistor I A1 and Si-Mos the driving signal PWM of transistor II A2 is high, and the A-phase Si-Mos the driving signal PWM of transistor III A3 and Si-Mos the driving signal PWM of transistor IV A4 is low.

[0140] if the A-phase voltage final modulation wave m A is less than the final triangular carrier , the comparator outputs a low level, and the A-phase Si-Mos Si-Mos the driving signal PWM of transistor I A1 and Si-Mos the driving signal PWM of transistor II A2 is low, and the A-phase Si-Mos the driving signal PWM of transistor III A3 and Si-Mos the driving signal PWM of transistor IV A4 is high.

[0141] Specifically, referring to Si-Mos , the method for generating the driving signal of the B-phase bridge arm combined switching device in the motor control circuit is:

[0142] the B-phase driving signal is finally modulated by comparing the B-phase voltage final modulation wave with the size of the final triangular carrierm B the size of the final triangular carrier wave ;

[0143] If the B-phase voltage final modulation wave m B is greater than or equal to the final triangular carrier wave , the comparator outputs a high level, and the B-phase Si-Mos tube I driving signal PWM B1 and Si-Mos tube II driving signal PWM B2 is high, and the B-phase Si-Mos tube III driving signal PWM B3 and Si-Mos tube IV driving signal PWM B4 is low.

[0144] If the B-phase voltage final modulation wave m B is less than the final triangular carrier wave , the comparator outputs a low level, and the B-phase Si-Mos Si-Mos tube I driving signal PWM B1 and Si-Mos tube II driving signal PWM B2 is low, and the B-phase Si-Mos tube III driving signal PWM B3 and Si-Mos tube IV driving signal PWM B4 is high.

[0145] Specifically, continuing to refer to Si-Mos , the method for generating the C-phase bridge arm combined switching device driving signal in the motor control circuit is:

[0146] comparing the C-phase voltage final modulation wave m C with the size of the final triangular carrier wave ;

[0147] If the C-phase voltage final modulation wave m C is greater than or equal to the final triangular carrier wave , the comparator outputs a high level, and the C-phase Si-Mos tube I driving signal PWM C1 and Si-Mos tube II driving signal PWM C2 is high, and the C-phase Si-Mos tube III driving signal PWM C3 is low.and Si-Mos PWM drive signal for transistor IV C4 Low level;

[0148] If the final modulation wave of phase C voltage m C Less than the final triangular carrier The comparator outputs a low level, thus obtaining phase C. Si-Mos Si-Mos PWM drive signal for transistor I C1 and Si-Mos PWM drive signal for transistor II C2 The low level is used to obtain the C phase by negating the low level using NOT. Si-Mos PWM drive signal for transistor III C3 and Si-Mos PWM drive signal for transistor IV C4 It is a high level.

[0149] To verify the effectiveness of the power decoupling capacitorless compressor drive device described in this invention, a simulation model was built using Simulink for verification.

[0150] A simulation model of a power-decoupled, electrolytic capacitor-free compressor drive was built in Simulink. DC bus thin-film capacitor. C 50μF DC bus inductor L The DC bus voltage setpoint of the power decoupling control module is 2mH in size. The voltage is 537V. The parameters of the permanent magnet synchronous motor M are as follows: stator resistance is 0.265Ω, direct-axis inductance is 0.0075H, quadrature-axis inductance is 0.0175H, flux linkage is 0.4Wb, and moment of inertia is 0.05kg.m. 2 The number of pole pairs is 3, the motor speed is 1140 r / min, and the load torque is 25 N·m. Si-Mos The waveform of the DC bus voltage of the existing three-phase electrolytic capacitor-free air conditioner compressor drive unit is shown. The DC bus voltage fluctuates greatly, with a fluctuation amplitude of approximately 370V to 740V. Si-Mos The DC bus voltage waveform of the power decoupling capacitorless compressor drive device described in this invention is reduced to less than 8V, with a fluctuation amplitude of approximately 532V~540V. It can be seen that the new method can effectively stabilize the DC bus voltage. Si-Mos The current waveform of the existing three-phase electrolytic capacitor-free air conditioner compressor drive unit is shown. At this time, the current waveform is poor, and the total harmonic distortion (THD) is 82.68%. Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-Mos Si-MosFor using the grid side current waveform of the power decoupled electrolytic capacitorless compressor driving device, the current waveform is greatly improved, and the THD is reduced to 32%. The above results prove the effectiveness of the power decoupled electrolytic capacitorless compressor driving device.

[0151] The above examples are used to explain the application, but not to limit the application, and any modifications and changes made to the application within the spirit and protection scope of the claims fall within the protection scope of the application.

Claims

1. A power decoupled electrolytic capacitor-less compressor drive apparatus, characterized by, The main circuit of the drive device comprises: a three-phase uncontrolled rectifier bridge, the input end of which is connected to a three-phase voltage; a power decoupling module, comprising: a DC bus inductor, one end of which is connected to the output end of the three-phase uncontrolled rectifier bridge; a combined switching device, connected to the other end of the DC bus inductor; a motor control circuit, the input end of which is connected to the output end of the power decoupling module, the motor control circuit being a three-phase completely symmetrical bridge circuit composed of the combined switching device as a bridge arm; a permanent magnet synchronous motor, connected to the output end of the motor control circuit; a DC bus film capacitor, connected between the power decoupling module and the motor control circuit; The drive device further comprises: a power decoupling control module, used to generate a drive signal of the combined switching device in the power decoupling module; a motor control module, used to generate a drive signal of the combined switching device in the motor control circuit; The combined switching device comprises: a first connection end; a second connection end, comprising a second connection end I and a second connection end II; an inductor assembly, comprising an inductor I and an inductor II, the first end of the inductor I and the first end of the inductor II being connected to the first connection end; Switching circuit I, including... Si-Mos Pipe I and Si-Mos A first series circuit formed by diodes II connected in series and a second series circuit formed by diodes I and II connected in series; Si-Mos Source connection of tube I Si-Mos The drain of tube II, Si-Mos The drain of diode I is connected to the anode of diode II. Si-Mos The connection point between the drain of diode I and the anode of diode II is connected to the second terminal of inductor II; the anode of diode I is connected to the cathode of diode II, and the cathode of diode I is connected to the second connection terminal I; Si-Mos The source of tube II is connected to the second connection terminal II; Switching circuit II, including... Si-Mos Pipe III and Si-Mos The third series circuit formed by diode IV connected in series, and the fourth series circuit formed by diode III and diode IV connected in series; Si-Mos Source connection of tube III Si-Mos The drain of tube IV, Si- Mos The drain of tube III is connected to the second connection terminal I; Si-Mos The source of diode IV is connected to the cathode of diode III. Si-Mos The connection point between the source of diode IV and the cathode of diode III is connected to the second terminal of inductor I; the anode of diode III is connected to the cathode of diode IV, and the anode of diode IV is connected to the second connection terminal II.

2. The power decoupled electrolytic capacitor less compressor drive of claim 1, wherein, The power decoupling control module comprises: a calculation module for calculating a direct current bus voltage error and a direct current bus voltage calculating a direct current bus voltage error ; current voltage loop PI module, to direct current bus voltage error proportional integral to get direct current bus current given value , direct current bus inductance current minus direct current bus current given value get direct current bus current error , direct current bus current error proportional integral to get direct current bus voltage modulation wave ; a bipolar modulation module modulating a dc bus voltage with a wave divided by the dc bus voltage to obtain a normalized dc bus voltage wave , generating a drive signal for a combination switching device in the power decoupling module in dependence on the normalized dc bus voltage wave and a size of a bipolar modulation triangular carrier wave .

3. The power decoupled electrolytic capacitor-less compressor drive of claim 2, wherein, The calculation module is based on the given value of the DC bus voltage. and DC bus voltage Calculate DC bus voltage error The method is as follows: DC bus voltage setpoint Reduce DC bus voltage Obtain DC bus voltage error .

4. The power decoupled electrolytic capacitorless compressor drive of claim 2, wherein, The current voltage loop PI module is multiplied by a proportional coefficient of the voltage loop PI controller to obtain a first intermediate value The DC bus voltage error is multiplied by an integral coefficient of the voltage loop PI controller to obtain a second intermediate value The DC bus voltage error is multiplied by an integral coefficient of the voltage loop PI controller to obtain a second intermediate value The DC bus voltage error is multiplied by an integral coefficient of the voltage loop PI controller to obtain a second intermediate value The DC bus voltage error is multiplied by an integral coefficient of the voltage loop PI controller to obtain a second intermediate value The DC bus voltage error is multiplied by an integral coefficient of the voltage loop PI controller to obtain a second intermediate value The DC bus voltage error is multiplied by an integral coefficient of the voltage loop PI controller to obtain a second intermediate value .

5. The power decoupled electrolytic capacitorless compressor drive of claim 2, wherein, The current-voltage loop PI module measures the DC bus current difference. The DC bus voltage modulation wave is obtained by performing proportional-integral operation. The method is: DC bus current error Multiply by the proportional gain of the current loop PI controller The third intermediate value is obtained: DC bus current error. Multiply by the integral coefficient of the current loop PI controller The fourth intermediate value is obtained by integration, and the DC bus voltage modulation wave is obtained by adding the third intermediate value to the fourth intermediate value. .

6. The power decoupled electrolytic capacitorless compressor drive of claim 2, wherein, The method for the bipolar modulation module to generate a drive signal of the combined switching device in the power decoupling module is: Comparing the normalized dc bus voltage modulation wave by a comparator to the size of a bipolar modulation triangle carrier ; If the normalized dc bus voltage modulation wave Less than or equal to bipolar modulation triangle carrier When, the comparator output high level, get Si-Mos The driving signal PWM1 of tube I and Si-Mos The driving signal PWM2 of tube II is high level, after taking non through NOT to high level Si-Mos The driving signal PWM3 of tube III and Si-Mos The driving signal PWM4 of tube IV is low level; If the normalized dc bus voltage modulation wave greater than the bipolar modulation triangular carrier The comparator output low level, get Si-Mos The driving signal PWM1 of tube I and Si-Mos The driving signal PWM2 of tube II is low, and the low level is obtained after taking NOT after Si-Mos The driving signal PWM3 of tube III and Si-Mos The driving signal PWM4 of tube IV is high.

7. The power decoupled electrolytic capacitor-less compressor drive apparatus as set forth in claim 1, wherein, The motor control module comprises: a d-axis voltage given value and a q-axis voltage given value are converted into axis voltages in a two-phase stationary coordinate system and axis voltages are converted into axis voltages and axis voltages are converted into three-phase voltage modulation waves The compressor drives the modulation module to take the maximum and minimum values ​​of the three-phase voltage modulation wave, add the maximum and minimum values ​​together, and divide by 2 to obtain the variable. The three-phase voltage modulation waves are reduced by variables respectively. The final modulated wave of the three-phase voltage is obtained; the compressor drive is modulated by a triangular carrier wave. Multiply by half the DC bus voltage Obtain the final triangular carrier Based on the final modulation wave of the three-phase voltage and the final triangular carrier wave The magnitude of the signal generates the drive signal for the combined switching devices in the motor control circuit.

8. The power decoupling electrolytic capacitor-less compressor drive of claim 7, wherein, The transformation module transforms a d-axis voltage given value and a q-axis voltage given value into a two-phase stationary coordinate system axis voltage and axis voltage The method is as follows: d-axis voltage command value times cos θ minus q-axis voltage command value times sin θ resulting in axis voltage ; d-axis voltage command value times sin θ minus q-axis voltage command value times cos θ resulting in axis voltage ; The conversion module converts Shaft voltage And Shaft voltage The method for converting into a three-phase voltage modulation wave is: A phase voltage modulation wave is equal to Shaft voltage ; minus one half times axis voltage plus one third times square root of two times axis voltage obtaining a phase b voltage modulation wave ; minus one half times axis voltage minus one third times square root of two times axis voltage obtain a c-phase voltage modulation wave .

9. The power decoupled electrolytic capacitorless compressor drive of claim 7, wherein, The compressor drive modulation module generates the drive signals for the combination switching devices in the motor control circuit according to the size of the final modulation wave and the final triangular carrier wave of the three-phase voltage The method for generating the drive signals for the combination switching devices in the motor control circuit is: Comparing the i-phase voltage final modulation wave by a comparator m i with the size of the final triangular carrier i = A, B, C; if the i-phase voltage final modulation wave m i greater than or equal to the final triangular carrier , the comparator output high level, get i-phase Si- Mos the driving signal PWM of tube I i1 and Si-Mos the driving signal PWM of tube II i2 high level, for high level through NOT get i-phase Si-Mos the driving signal PWM of tube III i3 and Si-Mos the driving signal PWM of tube IV i4 low level; if the i-phase voltage final modulation wave m i less than the final triangular carrier , the comparator output low level, get i-phase Si-Mos tube I drive signal PWM i1 and Si-Mos tube II drive signal PWM i2 for low level, low level by NOT after getting i-phase Si-Mos tube III drive signal PWM i3 and Si-Mos tube IV drive signal PWM i4 for high level.

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