CN111614253A - Quasi-resonant motor driving topological circuit - Google Patents
Quasi-resonant motor driving topological circuit Download PDFInfo
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- CN111614253A CN111614253A CN202010345141.2A CN202010345141A CN111614253A CN 111614253 A CN111614253 A CN 111614253A CN 202010345141 A CN202010345141 A CN 202010345141A CN 111614253 A CN111614253 A CN 111614253A
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- main switch
- power supply
- inductor
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
- H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
- H02M3/1584—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load with a plurality of power processing stages connected in parallel
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
- H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
- H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
- H02P27/085—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation wherein the PWM mode is adapted on the running conditions of the motor, e.g. the switching frequency
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0048—Circuits or arrangements for reducing losses
- H02M1/0054—Transistor switching losses
- H02M1/0058—Transistor switching losses by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The invention provides a quasi-resonant motor driving topological circuit, which is characterized in that: the power supply comprises a main switch, an auxiliary switch, a main switch parallel diode, a first diode, a second diode, an inductor, a capacitor, an inverter and a power supply; the power supply is a direct current power supply; the power supply, the main switch parallel diode, the main switch and the auxiliary switch are intersected at a point a; a main switch is connected with a diode in parallel and is internally provided with a fly-wheel diode; the main switch, the main switch parallel diode and the second diode are intersected at a point b; the capacitor and the inverter are intersected at a point c; point c connects point b; the second diode is connected with the inductor; the inductor, the auxiliary switch and the first diode are intersected at a point d; the first diode intersects the power supply at a point e; the capacitor intersects the inverter at a point f; point f connects to point e. The invention has the beneficial effects that: the volume size and the realization of the resonance function of the system are balanced, and the system has high power density, lower heat productivity and low EMI level.
Description
Technical Field
The invention relates to a soft switch, in particular to a quasi-resonant motor driving topological circuit.
Background
The most commonly used motor driving main circuit topological structure at present is a three-phase bridge inverter circuit, and the inverter circuit realizes the driving control of the motor by means of the high-frequency PWM action of a power switch. The switching of the power switch is performed under the action of respective gate driving pulses, and at the instant of switching on or off, the voltage applied across the switch or the current flowing through the switch is forced to be on or off, which is called a "hard" switch. The hard switching-on or hard switching-off can cause high switching loss, so that the heat productivity of the switch module is increased, and the requirement on system heat dissipation is increased; in addition, "hard" switching can cause very high dv/dt or di/dt in the circuitry, resulting in higher EMI. The above disadvantages make it difficult to achieve a higher power density for the driving system implemented by such a circuit topology.
As technology and manufacturing development requirements increase, motor drives require high power density, smaller volumetric sizes to facilitate easier integration into a particular use space or application. "soft" switching techniques have emerged that theoretically allow for reduced power consumption, thereby increasing driver power density, reducing system size, and reducing EMI. However, to realize the "soft" switching technology, it is generally necessary to add additional components to the original circuit structure to make the circuit in a resonant state, the addition of the resonant unit increases the system cost and complexity, and some solutions even consider one another, that is, the "soft" switching is realized, but the additional added part causes the system complexity, or the cost, or the volume, etc., even exceeds the original inverter itself, and the disadvantages are very prominent.
The following patents show the implementation of soft switching techniques and make preliminary analyses of their advantages and disadvantages.
For example, patent application No. CN 106533224a, which is filed by the present invention, discloses a soft switching inverter with a resonant dc link and a modulation method thereof. The topology in this patent implements ZVS (zero voltage) switching of the power switches on the inverter legs. The patent claims the advantage of eliminating the current reversal process of the auxiliary resonant inductor, thereby alleviating the problem of magnetic saturation of the inductor; the action frequency of the resonant circuit is reduced through a special improved SPWM (sinusoidal pulse width modulation) method, and the conduction loss of the resonant circuit is reduced.
Firstly, the adopted resonant components are more in number, 3 power switches, 2 power inductors, 4 power diodes and 3 resonant capacitors, capacitors are required to be connected in parallel to power switch tubes of 6 inverters to assist resonance, and more resonant elements and circuit structures are needed, so that not only is the system cost and complexity greatly increased, but also the control complexity and debugging difficulty are increased; secondly, the system needs to be controlled by matching with a special SPWM modulation method, otherwise, the control effect advantage is greatly reduced, and the modulation method has no universality; thirdly, the SVPWM method for controlling the motor with high performance, which is widely applied at present, is not necessarily applicable, even if the SVPWM method can be adopted, the advantage of the method can not be exerted because the SVPWM method is different from the special SPWM method provided by the invention.
Another invention, application publication No. CN106787903A, proposes a resonant very soft switching inverter circuit for driving a brushless dc motor. The resonant circuit scheme provided by the invention claims to have the advantages that a power switch connected in series on a direct current bus in the traditional resonant circuit is eliminated, so that the on-state loss of the part is eliminated, and the system efficiency is improved; in addition, the invention claims that the adopted resonant circuit has fewer resonant elements than the traditional resonant circuit, thereby reducing the cost and complexity of the circuit and reducing the overall size of the inverter.
One of the disadvantages of the invention is that up to 3 power switches are adopted, and the 3 power switches are respectively required to be driven and controlled, so that the complexity of system control is improved; in addition, another disadvantage of this invention is that the switch tube of the lower arm of the inverter bridge is connected in parallel with the resonance capacitor, and forms the resonance circuit together with other resonance components; the 3 power switches of the upper bridge arm are not connected with the resonant capacitor in parallel, which affects the symmetry and working characteristic consistency of the power switches on the upper arm and the lower arm of the three-phase bridge to a certain extent, can cause potential inconsistent switching states, generates larger harmonic waves in current and voltage components of the motor, potentially increases the working safety risk of the power switches, and reduces the system reliability; in addition, the invention designs a single-phase transformer which is connected in parallel in a direct current bus loop and completes the resonance of the circuit together with other auxiliary switches, when the circuit resonates, the amplitude of the current flowing through the primary side of the transformer can be up to 2 times of the load current, the large current amplitude directly causes the increase of the coil wire diameter of the transformer, thereby the volume of the transformer is increased, when the transformer is integrated in a system, the volume and the size of the system are inevitably increased, and when the power level of a driver is increased, the power of the transformer needs to be correspondingly increased.
Therefore, it is a challenge to achieve both the resonance of the circuit to achieve the soft switching function and to avoid the significant increase in system complexity, system volume and cost due to the presence of the resonant circuit.
Therefore, the market urgently needs a motor driving circuit which can realize the soft switching function, has less power devices of a system resonance unit, is compact as a whole, is simple to control, has smaller volume size of the resonance unit, and better balances the relationship between the volume size of the system and the realization of the resonance function, thereby realizing the high power density of a driver and having lower heat productivity and low EMI level.
Disclosure of Invention
In order to solve the technical problem, the invention discloses a quasi-resonant motor driving topological circuit, and the technical scheme of the invention is implemented as follows:
a quasi-resonant motor drive topology circuit, characterized by: the power supply comprises a main switch, an auxiliary switch, a main switch parallel diode, a first diode, a second diode, an inductor, a capacitor, an inverter and a power supply; the power supply is a direct current power supply; the power supply is intersected with the main switch parallel diode, the main switch and the auxiliary switch at a point a; a freewheeling diode is arranged in the main switch parallel diode; the main switch, the main switch parallel diode and the second diode intersect at a point b; the capacitor intersects the inverter at a point c; the point c connects the point b; the second diode is connected with an inductor; the inductor, the auxiliary switch and the first diode are intersected at a point d; the first diode intersects the power supply at a point e; the capacitor intersects the inverter at a point f; the point f connects the point e.
Preferably, the main switch, the auxiliary switch and the main switch are power switches.
Preferably, the first diode, the second diode and the main switch parallel diode are power diodes.
Preferably, the inductor is a power inductor.
Preferably, the main switches are of the same type as the power switches on the inverter legs.
By implementing the technical scheme of the invention, the technical problems of low power density, high heat productivity and high EMI level of a driver caused by the fact that the system resonance unit in the prior art has more power devices, a complex system, a large volume size of the resonance unit and incapability of balancing the relationship between the volume size of the system and the realization of a resonance function can be solved; by implementing the technical scheme of the invention, the system can realize less power devices of the resonant unit, is compact in whole, simple to control and smaller in volume size of the resonant unit, and better balances the relationship between the volume size of the system and the realization of the resonant function, thereby realizing the high power density of the driver and having the technical effects of lower heat productivity and low EMI level.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only one embodiment of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is an overall circuit state diagram of a quasi-resonant motor drive topology;
FIG. 2 is an initial state path diagram of a quasi-resonant motor drive topology;
FIG. 3 shows a quasi-resonant motor driving topology circuit t0-t1A state pathway diagram;
FIG. 4 shows a quasi-resonant motor driving topology circuit t1-t2A state pathway diagram;
FIG. 5 shows a quasi-resonant motor driving topology circuit t2-t3A state pathway diagram;
FIG. 6 shows a quasi-resonant motor driving topology circuit t3-t4A state pathway diagram;
FIG. 7 shows a quasi-resonant motor driving topology circuit t4-t5State path diagram
Fig. 8 is a state diagram of components of a quasi-resonant motor drive topology at different time periods.
In the above drawings, the reference numerals denote:
the circuit comprises a main switch (1), an auxiliary switch (2), a main switch parallel diode (3), a first diode (4), a second diode (5), an inductor (6), a capacitor (7), an inverter (8) and a power supply (9)
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
For convenience of description, the following is defined:
Vcr: the voltage across the capacitor (7);
Vdc: a power supply (9) voltage;
iDC: a load current in an operating state;
icr: a current flowing through the capacitor (7);
ilr: a current flowing through the inductor (6);
T1: a main switch (1);
T2: an auxiliary switch (2).
In a specific embodiment, as shown in fig. 1-6, a quasi-resonant motor drive topology, comprising: the circuit comprises a main switch (1), an auxiliary switch (2), a main switch parallel diode (3), a first diode (4), a second diode (5), an inductor (6), a capacitor (7), an inverter (8) and a power supply (9); the power supply (9) is a direct current power supply (9); the power supply (9) is intersected with the main switch parallel diode (3), the main switch (1) and the auxiliary switch (2) at a point a; a freewheeling diode (3) is connected in parallel in the main switch (1); the main switch (1), the main switch parallel diode (3) and the second diode (5) intersect at a point b; the capacitor (7) intersects the inverter (8) at a point c; the point c connects the point b; the second diode (5) is connected with an inductor (6); the inductor (6), the auxiliary switch (2) and the first diode (4) intersect at a point d; the first diode (4) intersects the power supply (9) at a point e; the capacitor (7) intersects the inverter (8) at a point f; the point f connects the point e; the main switch (1) and the auxiliary switch (2) are power switches; the first diode (4), the second diode (5) and the main switch parallel diode (3) are power diodes; the inductor (6) is a power inductor; the main switch (1) is of the same type as the power switches on the legs of the inverter (8).
In the specific embodiment, in the initial state, the main switch (1) is in a conducting state, the auxiliary switch (2) is in a disconnecting state, the capacitor (7) and the inverter (8) are in a state of working together, the resonant unit has no energy storage, and the current directions are a, b, c, f and e; at t0-t1At that time, the main switch (1) is turned off, the power supply (9) stops supplying power to the inverter (8), the capacitor (7) starts discharging, and power is supplied to the inverter (8) until VcrThe voltage across is zero, and then a period of time is up to t1At the moment, the power switch on the inverter (8) carries out switching state in the period, so that zero-voltage switching action is completely realized, and the current directions are c and f; at t1At the moment, the auxiliary switch (2) is turned on, the current direction of the power supply (9) is a, d, b, c, f, e, and the current ilrGradually increasing from zero to t2At the moment, the inductor (6) current reaches the load current iDCAmplitude, and simultaneously starting to charge the resonant capacitor (7), forming a series resonant circuit between the capacitor (7) and the inductor (6), and starting to increase the voltage at two ends of the capacitor (7) when V is greater than VcrHigher than VdcWhen the switch is turned on, the diode (3) connected in parallel with the two ends of the main switch (1) is conducted in the forward direction, and V iscrIs clamped toSupply voltage VDC. To t3At the moment, the main switch tube (1) is switched on at zero voltage, the switching-on of the main switch (1) causes the zero-voltage switching-off condition of the auxiliary switch (2) to be met, and then the auxiliary switch tube (2) is switched off. From t3From moment to moment, the main switch (1) is switched on, the auxiliary switch (2) is switched off, current flowing through the inductor (6) continues to flow through the first diode (4), meanwhile, the main switch parallel diode (3) is continuously in a forward conduction state, the current of the inductor (6) is gradually reduced, and the amplitude is reduced to load current. As the current flowing through the inductor (6) gradually decreases from t4From time to time, the main switch parallel diode (3) is cut off until the current drops to zero, the first diode (4) finishes the follow current and is converted into a cut-off state, and the circuit returns to the initial state.
Through the interaction among the modules, the system resonance unit has the advantages of few power devices, compact whole, simple control, small volume size of the resonance unit, and better balance between the volume size of the system and the realization of the resonance function, thereby realizing the high power density of the driver and having the technical effects of lower heat productivity and low EMI level.
It should be understood that the above-described embodiments are merely exemplary of the present invention, and are not intended to limit the present invention, and that any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Claims (5)
1. A quasi-resonant motor drive topology circuit, characterized by: the power supply comprises a main switch, an auxiliary switch, a main switch parallel diode, a first diode, a second diode, an inductor, a capacitor, an inverter and a power supply; the power supply is a direct current power supply;
the power supply is intersected with the main switch parallel diode, the main switch and the auxiliary switch at a point a; a freewheeling diode is arranged in the main switch parallel diode;
the main switch, the main switch parallel diode and the second diode intersect at a point b;
the capacitor intersects the inverter at a point c; the point c connects the point b;
the second diode is connected with an inductor;
the inductor, the auxiliary switch and the first diode are intersected at a point d;
the first diode intersects the power supply at a point e;
the capacitor intersects the inverter at a point f; the point f connects the point e.
2. The quasi-resonant motor drive topology of claim 1, wherein: the main switch, the auxiliary switch and the main switch parallel diode are power semiconductor switches.
3. The quasi-resonant motor drive topology of claim 1, wherein: the first diode, the second diode and the main switch parallel diode are power diodes.
4. The quasi-resonant motor drive topology of claim 1, wherein: the inductor is a power inductor.
5. The quasi-resonant motor drive topology of claim 1, wherein: the main switch is consistent with the power switch on the bridge arm of the inverter in type.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010345141.2A CN111614253A (en) | 2020-04-27 | 2020-04-27 | Quasi-resonant motor driving topological circuit |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010345141.2A CN111614253A (en) | 2020-04-27 | 2020-04-27 | Quasi-resonant motor driving topological circuit |
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| CN111614253A true CN111614253A (en) | 2020-09-01 |
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| CN202010345141.2A Pending CN111614253A (en) | 2020-04-27 | 2020-04-27 | Quasi-resonant motor driving topological circuit |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112366944A (en) * | 2020-12-03 | 2021-02-12 | 上海英联电子系统有限公司 | Soft switch resonance BOOST converter controlled by pulse width modulation |
| CN113541520A (en) * | 2021-07-20 | 2021-10-22 | 东北大学 | SVPWM-based resonant DC link three-phase inverter modulation method |
-
2020
- 2020-04-27 CN CN202010345141.2A patent/CN111614253A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112366944A (en) * | 2020-12-03 | 2021-02-12 | 上海英联电子系统有限公司 | Soft switch resonance BOOST converter controlled by pulse width modulation |
| CN112366944B (en) * | 2020-12-03 | 2023-09-22 | 上海英联电子系统有限公司 | Soft switch resonance BOOST converter controlled by pulse width modulation |
| CN113541520A (en) * | 2021-07-20 | 2021-10-22 | 东北大学 | SVPWM-based resonant DC link three-phase inverter modulation method |
| CN113541520B (en) * | 2021-07-20 | 2023-10-31 | 东北大学 | Modulation method of resonant direct-current link three-phase inverter based on SVPWM |
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