CN114362493A - Converter topology structure containing parallel harmonic compensation device and control method thereof - Google Patents
Converter topology structure containing parallel harmonic compensation device and control method thereof Download PDFInfo
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Abstract
The invention discloses a converter topological structure containing a parallel harmonic compensation device and a control method thereof. The converter comprises a main converter and a harmonic compensation converter. Each bridge arm of the main converter comprises an upper bridge arm power switch device and a lower bridge arm power switch device, and the structure of the harmonic compensation converter is the same as that of the main converter. The other ends of the main three-phase reactor and the harmonic compensation three-phase reactor are respectively connected with a three-phase winding of the motor. The invention adopts the three-phase controllable half-bridge circuit with small capacity and high switching frequency in parallel connection on the basis of the original low carrier ratio motor system, thereby effectively compensating the current harmonic waves on the three-phase winding of the motor, improving the motor efficiency, reducing the heating of the motor and the like.
Description
Technical Field
The invention belongs to the field of alternating current motor driving, and particularly relates to a converter topology structure with a parallel harmonic compensation device and a control method thereof.
Background
The application of an electronic power converter as a motor driving power source is a main mode of modern electric transmission. In the fields of high-power motor driving, high-speed motor driving and the like, the condition that the switching frequency of a converter is smaller than the fundamental frequency of a motor often occurs. The reasons for this are usually the high switching losses of the switching devices, the heavy volume of the heat sink and the excessive fundamental frequency of the motor. Under the condition of low-carrier-ratio driving, the harmonic content of the motor current is high, so that the motor generates heat, the torque pulsation is large, and the overall performance and efficiency of a motor driving system are reduced. This is even more serious if the motor inductance is small. Therefore, research aiming at reducing the motor current harmonic under the working condition of low carrier ratio is necessary.
In view of the above problems, three main solutions can be summarized from a large number of related studies: the passive filter is adopted, the sampling and switching frequency of the system is improved, and a multi-level topological structure is adopted. The passive filter device is a solution with a simple and reliable structure, but under a high-power working condition, the volume and the weight of the passive filter device are often larger. The switching frequency can be increased by adopting a novel SiC or GaN device, and the problem is fundamentally solved. However, the price of the high frequency device is still high at present, and the cost is too high for most projects, so that the high frequency device is not suitable for use. The multi-level topology reduces current harmonics by increasing the number of levels of the output voltage by adding switching devices. The scheme needs to use the power switch device in a doubling way, and has a complex control mode and reduced system reliability. Therefore, the problem of motor current harmonic suppression under the condition of low carrier ratio needs to be comprehensively considered in the aspects of converter cost, system reliability, volume and weight requirements, control algorithm complexity and the like aiming at different engineering backgrounds.
At present, relevant research at home and abroad mainly focuses on the three methods and mixed use of the three methods, and aims to find an optimal solution which is comprehensively considered in all aspects. With the increasing development of high-power motor systems and high-speed direct-drive motor systems, the drive control system in the field needs to be developed towards high reliability, small integration, flexibility and the like in the future.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a converter topological structure with a parallel harmonic compensation device and a control method thereof, so as to solve the problem of high motor current harmonic content caused by a low system carrier ratio and achieve the purposes of reducing current harmonics, optimizing torque ripple, reducing motor temperature rise and improving system efficiency.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
a converter topological structure comprising a parallel harmonic compensation device comprises a main converter and a harmonic compensation converter, wherein each bridge arm of the main converter is provided with a first upper bridge arm power switch device and a first lower bridge arm power switch device;
the harmonic compensation converter comprises three parallel bridge arms and a second direct current bus capacitor group, wherein each bridge arm is provided with a second upper bridge arm power switch device and a second lower bridge arm power switch device; the connection point of the first upper bridge arm power switching device and the second lower bridge arm power switching device is an output node of the bridge arms, and the output node of each bridge arm is connected with a first end of a harmonic compensation reactor;
the output power of the harmonic compensation converter is smaller than that of the main converter, and the frequencies of the first upper bridge arm power switching device and the first lower bridge arm power switching device are both smaller than those of the second upper bridge arm power switching device and the second lower bridge arm power switching device;
the second end of the main reactor is connected with the second end of the harmonic compensation reactor, and the joint of the two second ends is connected to the motor.
The invention is further improved in that:
preferably, the upper nodes of the three bridge arms of the main converter are connected with the anode of the first dc bus capacitor bank, and the lower nodes of the three bridge arms are connected with the cathode of the first dc bus capacitor bank.
Preferably, the harmonic compensation converter output power is less than 30% of the main converter output power.
Preferably, the switching frequency of the second upper bridge arm power switching device and the second lower bridge arm power switching device is greater than that of the first upper bridge arm power switching device; and the switching frequency of the second upper bridge arm power switching device and the second lower bridge arm power switching device is greater than that of the first lower bridge arm power switching device.
Preferably, the switching frequency of the second upper bridge arm power switching device and the switching frequency of the second lower bridge arm power switching device are 5 times or more of the switching frequency of the first upper bridge arm power switching device; and the switching frequency of the second upper bridge arm power switching device and the switching frequency of the second lower bridge arm power switching device are 5 times or more of the switching frequency of the first lower bridge arm power switching device.
Preferably, the circuit equation of the converter with the parallel harmonic compensation device is as follows:
vabc、vfabc、vmabc、iabc、ifabcand imabcThe three-phase voltage of the joint of the main reactor and the harmonic compensation reactor, the voltage of a three-phase output node of the harmonic compensation converter, the voltage of a three-phase output node of the main converter, the current of a three-phase winding of the motor, the three-phase current of the harmonic compensation reactor and the three-phase current of the main reactor are represented respectively.
Preferably, the motor is a three-phase half-bridge drivable motor.
Preferably, the main converter and the harmonic compensation converter are both three-phase half-bridge converters; the main reactor and the harmonic compensation reactor are both three-phase filter reactors.
A control method of the converter topological structure with the parallel harmonic compensation device comprises the steps of collecting bus voltage of the harmonic compensation converter, obtaining a voltage error signal by subtracting the bus voltage from a voltage reference value, and forming a reference value of dq axis current by the voltage error signal and a current error signal of a main converter through a PI (proportional-integral) controller; collecting a three-phase current value of the harmonic compensation reactor, and converting the three-phase current value into a dq coordinate system through coordinates to be used as a current feedback value of a current inner ring; and (3) subtracting the reference value of the dq-axis current from the current feedback value, obtaining a voltage output signal of the dq axis through the difference value by an FC current controller, obtaining an alpha beta-axis voltage signal through coordinate transformation of the voltage output signal, obtaining a control signal of a power switching device of the harmonic compensation converter (2) through PWM voltage modulation of the alpha beta-axis voltage signal, and controlling the second upper bridge arm power switching device and the second lower bridge arm power switching device through the control signal.
Preferably, the difference is made between the rotating speed signal of the main converter and the reference rotating speed signal to obtain a rotating speed error signal, and the rotating speed error signal obtains a q-axis current reference value through a PI controller; collecting the current of a three-phase winding of the motor, and converting the current into a dq coordinate system through coordinates to obtain a current feedback value of a current inner loop; subtracting the dq-axis current feedback value from the dq-axis current reference value to obtain a dq-axis current error signal; the dq axis current error signal is processed by an MC current controller to obtain a dq axis voltage output signal; the voltage output signal of the dq axis obtains an alpha beta axis voltage signal through coordinate transformation, and the alpha beta axis voltage signal is modulated through PWM voltage to obtain a control signal of a power switching device of a main converter; and controlling a first upper bridge arm power switch and a first lower bridge arm power switch of the main converter (1) through control signals.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses a converter topology structure containing a parallel harmonic compensation device, which comprises two three-phase half-bridge converters, two three-phase filter reactors and two groups of direct-current bus capacitors. The converter comprises a main converter and a harmonic compensation converter. Each bridge arm of the main converter comprises an upper bridge arm power switch device and a lower bridge arm power switch device, and the structure of the harmonic compensation converter is the same as that of the main converter. The other ends of the main three-phase reactor and the harmonic compensation three-phase reactor are respectively connected with a three-phase winding of the motor. The main converter controls the main functions of the motor and provides active power; the harmonic compensation converter inhibits current harmonic waves on a three-phase winding of the motor and stabilizes the bus capacitance voltage of the motor. The capacity of the harmonic compensation converter can be designed according to the harmonic content of the winding current, and whether the harmonic compensation converter works or not can be controlled during operation. The invention is suitable for high-power or high-speed motors, can flexibly and effectively inhibit the harmonic content of the system and improve the system performance of the motor. The invention adopts the three-phase controllable half-bridge circuit with small capacity and high switching frequency in parallel connection on the basis of the original low carrier ratio motor system, thereby effectively compensating the current harmonic waves on the three-phase winding of the motor, improving the motor efficiency, reducing the heating of the motor and the like. Because the added harmonic compensation converter has smaller capacity and higher frequency, the volume and the weight of the three-phase reactor are smaller, so the added cost, the volume and the weight of the system are relatively reasonable, and the three-phase reactor is a reasonable scheme which can effectively inhibit the current ripple of the motor under the working condition of low carrier ratio.
The invention also discloses a control method of the converter topology structure containing the parallel harmonic compensation device, and the converter topology corresponding to the control method adopts two three-phase half-bridges with different capacities and switching frequencies and two three-phase reactors with different powers and switching frequencies to be connected in parallel for unified control. The control method uniformly controls the two three-phase half-bridge converters, and can more effectively suppress current harmonics of the motor winding. Under the working conditions that the rotating speed of the motor is low and the carrier wave ratio is large, namely when the current harmonic wave of the motor is small, the harmonic wave compensation converter can stop working, and the control is flexible, reliable, simple and convenient.
Drawings
Fig. 1 is a schematic diagram of a converter topology including a parallel harmonic compensation device.
Fig. 2 is a block diagram of a unified control for a converter with parallel harmonic compensation devices during normal operation.
Fig. 3 is a block diagram of a unified control for a converter with parallel harmonic compensation devices to cut off harmonic compensation portions.
Wherein, 1-main converter; 2-a harmonic compensating converter; 3, a motor; 4-a main reactor; 5-harmonic compensation reactor.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings:
in the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention; the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; furthermore, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly and encompass, for example, both fixed and removable connections; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The converter with the parallel harmonic compensation device comprises: the three-phase half-bridge converter comprises two three-phase half-bridge converters, two three-phase filter reactors and two groups of direct current bus capacitors.
Specifically, the converter includes a main converter 1 and a harmonic compensation converter 2. Each bridge arm of the main converter 1 comprises a first upper bridge arm power switch device and a first lower bridge arm power switch device, an upper node of each first upper bridge arm power switch device is connected with the anode of a first direct current bus capacitor set, and a lower node of each first lower bridge arm power switch device is connected with the cathode of the first direct current bus capacitor set. And the lower node of the first upper bridge arm power switching device is connected with the upper node of the first lower bridge arm power switching device and is used as an output node of the bridge arm, and the output node of each bridge arm is connected with the first end of the main reactor 4. The switching frequencies of the first upper bridge arm power switching device and the first lower bridge arm power switching device are both less than 10kHz, and the first upper bridge arm power switching device and the first lower bridge arm power switching device can be IGBTs or MOSFETs.
The harmonic compensating converter 2 is structurally the same as the main converter 1. The wave compensating converter 2 comprises three parallel bridge arms and second direct current bus capacitor groups, each bridge arm is provided with a second upper bridge arm power switch device and a second lower bridge arm power switch device, a lower node of the first upper bridge arm power switch device is connected with an upper node of the second lower bridge arm power switch device, an upper node of each second upper bridge arm power switch device is connected with the anode of the second direct current bus capacitor group, and a lower node of each second lower bridge arm power switch device is connected with the cathode of the second direct current bus capacitor group; and the connection point of the first upper bridge arm power switching device and the second lower bridge arm power switching device is an output node of the bridge arms, and the output node of each bridge arm is connected with the first end of the harmonic compensation reactor 5. The second upper bridge arm power switch device and the second lower bridge arm power switch device are more than 10 times of the switching frequency of the first upper bridge arm power switch device and the first lower bridge arm power switch device, and the second upper bridge arm power switch device and the second lower bridge arm power switch device can be IGBTs or MOSFETs.
And a second end of the main reactor 4 is connected with a second end of the harmonic compensation reactor 5, and the joint is connected with a three-phase winding of the motor 3. The main reactor 4 and the harmonic compensation reactor 5 are three-phase filter reactors.
The main converter 1 outputs active power required by a system to provide energy for a load motor 3 and a bus capacitor of the harmonic compensation converter 2. The harmonic compensation converter 2 provides reactive compensation for the main converter 1 and the load motor 3 system, counteracts harmonic current on the three-phase output node side of the main converter 1, and reduces current harmonic on the three-phase winding of the motor 3.
The switching frequency of the power devices in the harmonic compensation converter 2 is higher than the switching frequency of the power devices in the main converter 1. The output power of the harmonic compensation converter 2 depends on the current harmonic magnitude of the three-phase winding of the motor 3 when the main converter 1 and the load motor 3 are operated in a system. In general, the output power of the harmonic compensation converter 2 is within 30% of the output power of the main converter 1, specifically depending on the switching frequency of the main converter 1, the motor 3, the fundamental frequency, and the three-phase inductance of the motor 3. Namely, the capacity of the power switch device of the harmonic compensation converter 2 is small, the switching frequency is high, and the capacities of the direct current bus capacitor bank and the harmonic compensation reactor 5 of the harmonic compensation converter 2 are small, so that the volume and the weight are small.
The electrode 3 is a three-phase half-bridge drivable motor, such as a permanent magnet motor, an asynchronous motor and the like.
The converter circuit equation with the parallel harmonic compensation device can be expressed as:
wherein v isabc、vfabc、vmabc、iabc、ifabcAnd imabcAll represent three-dimensional vectorsThe three-phase voltage at the connection point of the main reactor 4 and the harmonic compensation reactor 5, the voltage of the three-phase output node of the harmonic compensation converter 2, the voltage of the three-phase output node of the main converter 1, the current of the three-phase winding of the load motor 3, the three-phase current of the harmonic compensation reactor 5 and the three-phase current of the main reactor 4 are respectively shown. The integral mathematical model of the topology can be obtained by substituting the motor 3 equation. Integral mathematical model withma、imb、imc、ifa、ifbAnd ifcAnd obtaining an integral mathematical model of the converter topology and the load motor 3 under the dq axis through coordinate transformation as a state variable. The relationship between the coordinate transformation and the current under different coordinate systems is as follows:
the converter comprising the parallel harmonic compensation device can decompose the three-phase winding current of the motor 3 into the main three-phase reactor current and the three-phase current of the harmonic compensation reactor 5 according to the kirchhoff current law. i.e. ifabcAnd imabcAnd converting the coordinate system into a dq coordinate system through coordinate transformation, and realizing the cooperative control of the motor 3 by the double converters. The main converter 1 controls the rotation speed, flux linkage and torque of the motor 3 in a conventional control mode, and the harmonic compensation converter 2 controls the bus capacitance voltage and generates current harmonics opposite to those on the main reactor 4.
The main converter 1 is controlled by a rotating speed outer ring, the rotating speed outer ring controller outputs a current inner ring input as an output, coordinates are converted to an alpha beta axis after passing through the current ring controller, and 6 paths of PWM signals are output to each power device of the main converter 1 through modulation. The control mode of the harmonic compensation converter 2 is a bus voltage outer ring, and the input signal of a current ring is the sum of the output of a voltage ring controller and the signal error of the current ring of the main converter 1. Similarly, the coordinates are transformed to the α β axis after passing through the current loop controller, and 6 paths of PWM signals are output to each power device of the harmonic compensation converter 2 by modulation. Since the switching frequencies of the main converter 1 and the harmonic compensation converter 2 are different, the control algorithm is divided into two parts with different frequencies. The method comprises the steps that a main converter 1 rotating speed loop, a main converter 1 current signal error calculation and harmonic compensation converter 2 control algorithm are high-frequency calculation parts, and a main converter 1 current loop and a main converter 1 modulation part are low-frequency calculation parts.
When the current harmonic of the load motor 3 is in an acceptable range, for example, when the load motor operates in a working condition with a high carrier ratio such as low speed, the operation of the harmonic compensation converter 2 can be stopped. The harmonic compensation converter 2 is convenient and quick to start and stop and can be flexibly controlled according to actual working conditions.
The following is further described in conjunction with specific examples:
examples
The embodiment of the motor 3 driving system provided by the invention is controlled by a surface-mounted permanent magnet synchronous motor. The surface-mounted permanent magnet synchronous motor comprises permanent magnets, windings, a rotating shaft and other general structural members of the motor 3.
Fig. 1 shows a converter topology according to the present invention and a connection relationship with a motor 3 shown in fig. 1. The three-phase half-bridge converter comprises a main converter 1, a main reactor 4, a harmonic compensation converter 2, a harmonic compensation reactor 5 and a load motor 3, wherein the main converter 1 and the harmonic compensation converter 2 are three-phase half-bridge converters.
The main converter 1 comprises a second direct current bus capacitor set and three bridge arms, wherein an upper node of each bridge arm is connected to the anode of the direct current bus capacitor set, and a lower node of each bridge arm is connected to the cathode of the first direct current bus capacitor set. The whole capacitance value of the first direct current bus capacitor set is CmThe bulk voltage is udc1. The voltage of an output node of each phase of bridge arm of the main converter 1 is v respectivelyma、vmbAnd vmc(in this embodiment, the power switching device of the main converter 1 is an IGBT). One end of the main reactor 4 is connected with a three-phase output node of the main converter 1, and the other end is connected with a three-phase winding wire outlet end of the motor 3. The inductance value of the main reactor 4 is LmThe three phases of the current flow are ima、imbAnd imc。
The harmonic compensation converter 2 comprises a second direct-current bus capacitor bank and three bridge arms, wherein an upper node of each bridge arm is connected to the anode of the second direct-current bus capacitor bank, and a lower node of each bridge arm is connected to the cathode of the direct-current bus capacitor bank. The integral capacitance value of the DC bus capacitor bank is CfThe bulk voltage is udc2. The output node voltage of each phase of bridge arm of the harmonic compensation converter 2 is vfa、vfbAnd vfc(in this embodiment, SiC-MOSFET is used as the power switching device of the harmonic compensating converter 2). One end of the harmonic compensation reactor 5 is connected with a three-phase output node of the harmonic compensation converter 2, and the other end is connected with a three-phase winding outlet end of the motor 3. The inductance value of the harmonic compensation reactor 5 is LfThe three phases of the current flow are ifa、ifbAnd ifc. The voltages at the connection points of the main reactor 4 and the harmonic compensation reactor 5 are respectively va、vbAnd vc。
The load motor 3 selected in this embodiment is a surface-mounted permanent magnet synchronous motor 3, three-phase resistance, inductance and back electromotive force of the surface-mounted permanent magnet synchronous motor are respectively represented by R, L and e, and currents on three-phase windings of the motor 3 are respectively ia、ibAnd ic。
As shown in fig. 1, the main converter 1 and the harmonic compensating converter 2 differ in power and switching frequency. The main converter 1 and the main reactor 4 match in power requirements. The main converter 1 has a lower switching frequency, and the frequency of the main reactor 4 is matched with the fundamental frequency of the motor 3. The power requirements of the harmonic compensation converter 2 and the harmonic compensation reactor 5 are matched. The harmonic compensation converter 2 has high switching frequency, and the frequency of the harmonic compensation reactor 5 is matched with the harmonic frequency of the motor 3 capable of compensating. The power design of the branch of the harmonic compensation converter 2 depends on the harmonic content of the motor 3 (in this embodiment, the power of the harmonic compensation converter 2 is 30% of that of the main converter 1).
As shown in FIG. 2, the unified control method for converter topology with parallel harmonic compensation device according to the present invention includes compensating converter 2 for the rotating speed, dq axis current and harmonic of surface-mounted permanent magnet synchronous motor 3And controlling and compensating the bus voltage and the current harmonic of the winding of the motor 3. Because the mathematical model of the converter topology with the parallel harmonic compensation device is transformed to the dq coordinate system, the main converter 1 and the harmonic compensation converter 2 can be decoupled to a certain degree, but coupling still exists. The main converter 1 is controlled by a rotating speed outer ring and a current inner ring. Obtaining a rotation speed signal omega by a rotor position sensor or a position-free control algorithmeThen, the reference speed signal omegaerefMaking difference to obtain a rotating speed error signal, and then obtaining a reference value i of the q-axis current through a PI (proportional integral) controllermqref. Collecting 4 three-phase current i of main reactorma、imbAnd imcTransforming the coordinates into dq coordinate system to obtain imdAnd imqAs the current feedback value of the current inner loop. Reference value i of dq axis currentmdrefAnd imqrefAnd dq axis current feedback value imdAnd imqObtaining a dq axis current error signal delta i by differencemdAnd Δ imqAnd respectively obtaining voltage output signals of dq axes through the MC current controller. The alpha and beta axis voltage signals obtained by coordinate transformation are modulated by PWM voltage to obtain control signals S of 6 power switching devices of the main converter 1m1-6。
The control mode of the harmonic compensation converter 2 is a bus voltage outer ring and a current inner ring. By collecting the bus voltage u of the harmonic compensating converter 2dc2And is in parallel with the voltage reference value udc2refMaking difference to obtain voltage error signal, then making PI controller to obtain udc2outAnd Δ imqAdding the reference values i constituting the q-axis currentfqref. Collecting three-phase current i of harmonic compensation reactor 5fa、ifbAnd ifcTransforming the coordinates into dq coordinate system to obtain ifdAnd ifqAs the current feedback value of the current inner loop. Harmonic compensation converter 2dq axis current reference value delta imdAnd ifqrefFor the main converter 1dq axis current error signal delta imdAnd Δ imqAnd voltage outer loop output signal udc2outThe harmonic compensation converter 2dq axis current reference value delta imdAnd ifqrefAnd dq axis current feedback value ifdAnd ifqAnd (5) performing difference making, and obtaining voltage output signals of dq axes through FC current controllers respectively. The alpha and beta axis voltage signals obtained by coordinate transformation are modulated by PWM voltage to obtain control signals S of 6 power switching devices of the harmonic compensation converter 2f1-6。
Because the converter topology with the parallel harmonic compensation device has power switching devices which operate at high and low frequencies, the control method is also divided into a high-frequency part and a low-frequency part. When the harmonic content of the motor current is large, the main converter 1 and the harmonic compensation converter 2 are controlled in a unified mode at the moment. As shown in fig. 2, the high frequency part and the low frequency part are running simultaneously, the high frequency part updates faster and the low frequency part updates slower. The method comprises the steps that a main converter 1 rotating speed loop, a main converter 1 current signal error calculation and harmonic compensation converter 2 control algorithm are high-frequency calculation parts, and a main converter 1 current loop and a main converter 1 modulation part are low-frequency calculation parts. The control algorithm frequency division can reduce the calculation force demand on the main control chip and save the cost.
Fig. 3 shows a unified control method when the converter with the parallel harmonic compensation device stops the harmonic compensation part. When the motor 3 operates under the working condition of low rotating speed and the like with low current harmonic content, the harmonic compensation part does not need to work, the operation of the harmonic compensation part can be stopped, and the converter is integrally switched to another control method. As shown in fig. 3, at this time, all of the 6 switching tubes of the harmonic compensation converter 2 are turned off, that is, the harmonic compensation converter 2 stops working, and the system operates in a normal operating condition where the main converter 1 controls the motor alone. This is beneficial to reducing the switching loss of the device and prolonging the service life of the converter. In this control mode, the control method of the main converter 1 is the same as that in normal operation, and the control signal of the power switching device of the harmonic compensation converter 2 is changed to a low level. Meanwhile, the overall control method adopts low-frequency calculation.
The control method shown in fig. 3 can be smoothly switched with the control method shown in fig. 2 without impacting the stability of the system.
In summary, the invention adopts a three-phase half-bridge converter parallel topology, which is divided into the main converter 1 and the harmonic compensation converter 2, and the power and the switching frequency of the main converter and the harmonic compensation converter are different, so that the current harmonic of the motor 3 can be effectively inhibited under a unified control method, and the harmonic compensation converter 2 can be started and stopped at any time, and the control mode is flexible. On the whole, the increased cost, volume and weight are all in a reasonable range, and the method is a novel effective driving topology and control method for reducing the current harmonic content under the working condition of low carrier ratio.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (10)
1. A converter topology structure containing a parallel harmonic compensation device is characterized by comprising a main converter (1) and a harmonic compensation converter (2), wherein each bridge arm of the main converter (1) is provided with a first upper bridge arm power switch device and a first lower bridge arm power switch device, a node between the first upper bridge arm power switch and the first lower bridge arm power switch is an output node of the bridge arm, and the output node of each bridge arm is connected with a first end of a main reactor (4);
the harmonic compensation converter (2) comprises three parallel bridge arms and a second direct-current bus capacitor group, wherein each bridge arm is provided with a second upper bridge arm power switch device and a second lower bridge arm power switch device; the connection point of the first upper bridge arm power switching device and the second lower bridge arm power switching device is an output node of the bridge arms, and the output node of each bridge arm is connected with a first end of a harmonic compensation reactor (5);
the output power of the harmonic compensation converter (2) is less than that of the main converter (1), and the frequencies of the first upper bridge arm power switch device and the first lower bridge arm power switch device are both less than those of the second upper bridge arm power switch device and the second lower bridge arm power switch device;
the second end of the main reactor (4) is connected with the second end of the harmonic compensation reactor (5), and the joint of the two second ends is connected to the motor (3).
2. The converter topology structure with the parallel harmonic compensation device according to claim 1, characterized in that the upper nodes of the three legs of the main converter (1) are commonly connected with the positive electrode of the first dc bus capacitor set, and the lower nodes of the three legs are commonly connected with the negative electrode of the first dc bus capacitor set.
3. The converter topology with the parallel harmonic compensation device according to claim 1, characterized in that the output power of the harmonic compensation converter (2) is less than 30% of the output power of the main converter (1).
4. The converter topology structure with the parallel harmonic compensation device according to claim 1, wherein the switching frequency of the second upper bridge arm power switching device and the second lower bridge arm power switching device is greater than that of the first upper bridge arm power switching device; and the switching frequency of the second upper bridge arm power switching device and the second lower bridge arm power switching device is greater than that of the first lower bridge arm power switching device.
5. The converter topology structure with the parallel harmonic compensation device according to claim 1, wherein the switching frequency of the second upper bridge arm power switching device and the switching frequency of the second lower bridge arm power switching device are 5 times or more of the switching frequency of the first upper bridge arm power switching device; and the switching frequency of the second upper bridge arm power switching device and the switching frequency of the second lower bridge arm power switching device are 5 times or more of the switching frequency of the first lower bridge arm power switching device.
6. The converter topology with the parallel harmonic compensation device according to claim 1, wherein the circuit equation of the converter with the parallel harmonic compensation device is as follows:
vabc、vfabc、vmabc、iabc、ifabcand imabcThe three-phase voltage respectively represents the three-phase voltage of the joint of the main reactor (4) and the harmonic compensation reactor (5), the voltage of the three-phase output node of the harmonic compensation converter (5), the voltage of the three-phase output node of the main converter (1), the current of the three-phase winding of the motor (3), the three-phase current of the harmonic compensation reactor (5) and the three-phase current of the main reactor (4).
7. Converter topology with parallel harmonic compensation device according to claim 1, characterized in that the electrical machine (3) is a three-phase half-bridge drivable electrical machine.
8. The converter topology structure with the parallel harmonic compensation device according to claim 1, wherein the main converter (1) and the harmonic compensation converter (2) are three-phase half-bridge converters; the main reactor (4) and the harmonic compensation reactor (5) are both three-phase filter reactors.
9. The control method of the converter topology structure with the parallel harmonic compensation device according to claim 1, characterized by collecting the bus voltage of the harmonic compensation converter (2), and obtaining a voltage error signal by making a difference between the bus voltage and a voltage reference value, wherein the voltage error signal and the current error signal of the main converter (1) form a reference value of dq-axis current through a PI controller; collecting a three-phase current value of the harmonic compensation reactor (5), and converting the three-phase current value into a dq coordinate system through a coordinate to be used as a current feedback value of a current inner ring; and (3) subtracting the reference value of the dq-axis current from the current feedback value, obtaining a voltage output signal of the dq axis through the difference value by an FC current controller, obtaining an alpha beta-axis voltage signal through coordinate transformation of the voltage output signal, obtaining a control signal of a power switching device of the harmonic compensation converter (2) through PWM voltage modulation of the alpha beta-axis voltage signal, and controlling the second upper bridge arm power switching device and the second lower bridge arm power switching device through the control signal.
10. The control method according to claim 9, characterized in that the difference is made between the rotation speed signal of the main converter (1) and the reference rotation speed signal to obtain a rotation speed error signal, and the rotation speed error signal is used for obtaining a q-axis current reference value through a PI controller; collecting the current of a three-phase winding of the motor, and converting the current into a dq coordinate system through coordinates to obtain a current feedback value of a current inner loop; subtracting the dq-axis current feedback value from the dq-axis current reference value to obtain a dq-axis current error signal; the dq axis current error signal is processed by an MC current controller to obtain a dq axis voltage output signal; the voltage output signal of the dq axis obtains an alpha beta axis voltage signal through coordinate transformation, and the alpha beta axis voltage signal is modulated through PWM voltage to obtain a control signal of a power switching device of a main converter (1); and controlling a first upper bridge arm power switch and a first lower bridge arm power switch of the main converter (1) through control signals.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6385064B1 (en) * | 2001-05-07 | 2002-05-07 | Rockwell Technologies, Llc | Harmonic blocking reactor for nine-phase converter system |
| CN107482940A (en) * | 2017-07-27 | 2017-12-15 | 东南大学 | A kind of Modular multilevel converter for high-speed permanent magnet motor drive system |
| WO2021179709A1 (en) * | 2020-03-11 | 2021-09-16 | 合肥科威尔电源***股份有限公司 | Three phase dual active bridge direct current converter control system and control method |
-
2022
- 2022-01-11 CN CN202210026881.9A patent/CN114362493A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6385064B1 (en) * | 2001-05-07 | 2002-05-07 | Rockwell Technologies, Llc | Harmonic blocking reactor for nine-phase converter system |
| CN107482940A (en) * | 2017-07-27 | 2017-12-15 | 东南大学 | A kind of Modular multilevel converter for high-speed permanent magnet motor drive system |
| WO2021179709A1 (en) * | 2020-03-11 | 2021-09-16 | 合肥科威尔电源***股份有限公司 | Three phase dual active bridge direct current converter control system and control method |
Non-Patent Citations (1)
| Title |
|---|
| YANG LIANG等: "Current Control System of Hybrid Converter for Suppressing Current Harmonics", 2021 IEEE INTERNATIONAL ELECTRIC MACHINES & DRIVES CONFERENCE (IEMDC), pages 1 - 6 * |
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