CN103701309A - Alternating-direct current power supply system for variable frequency equipment and variable frequency air conditioner - Google Patents

Alternating-direct current power supply system for variable frequency equipment and variable frequency air conditioner Download PDF

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CN103701309A
CN103701309A CN201310634848.5A CN201310634848A CN103701309A CN 103701309 A CN103701309 A CN 103701309A CN 201310634848 A CN201310634848 A CN 201310634848A CN 103701309 A CN103701309 A CN 103701309A
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power supply
direct current
inversion unit
voltage
controller
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CN103701309B (en
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陈坚波
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Guangdong Kelon Air Conditioner Co Ltd
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Guangdong Kelon Air Conditioner Co Ltd
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Abstract

The invention discloses an alternating-direct current power supply system for variable frequency equipment and a variable frequency air conditioner. The alternating-direct current power supply system comprises direct current power supply wiring terminals, alternating current power supply wiring terminals, a direct current sampling circuit and a controller; the alternating current power supply wiring terminals are connected with a direct current bus voltage input end of a first inversion unit through a first rectifier bridge; the direct current power supply wiring terminals are connected with the direct current bus voltage input end of the first inversion unit sequentially through a second inversion unit, an isolation transformer and a second rectifier bridge; and the direct current sampling circuit acquires direct current voltage input by the direct current power supply wiring terminals and outputs to the controller through the direct current isolation transformer. Since the alternating-direct current power supply system is designed, the variable frequency equipment such as the variable frequency air conditioner can be directly powered by an alternating current mains supply and a public direct current power grid or direct current energy generated by renewable energy sources; the working requirements of long-term continuous operation of the variable frequency equipment can be met; and the variable frequency equipment is greener and more environment-friendly.

Description

Supplied by AC/DC electricity system and transducer air conditioning for frequency conversion equipment
Technical field
The invention belongs to frequency conversion system technical field, specifically, relate to a kind of transducer air conditioning that is used to frequency conversion equipment the electric supply system of power supply supply to be provided and to adopt described electric supply system design.
Background technology
Along with the application of solar energy, wind energy and geothermal energy, in global range, use the area of regenerative resource power supply more and more.The electric energy sending due to regenerative resource is direct current mostly, and existing most electric equipment requirement accesses is Alternating Current Power Supply, therefore, for the direct current energy that can simply and easily regenerative resource be produced uses fully, current solution is mainly that the direct current energy that regenerative resource is produced is transformed into AC energy, then being incorporated to electric main electrical network, is that various electric equipment power supplies are used by utility grid.
But, the electric company that this grid-connected power supply design is only applicable to various countries is used, and need to drop into high construction cost, build regenerative resource transformer station, to realize the supply of regenerative resource to traditional energy, no matter from substation site selection and the electrical network in early stage, lay, or from power grid maintenance in the future, all have difficulty in various degree.And, for some, the country of public direct-current electrical network or enterprise or the family that sets up alone regenerative resource power supply equipment have been disposed, existingly only support that the electric equipment of Alternating Current Power Supply also cannot be made full use of these energy, just cause thus the utilance of public direct-current electrical network and regenerative resource obviously not enough.
Summary of the invention
The object of the present invention is to provide a kind of frequency conversion equipment supplied by AC/DC electricity system of supporting two kinds of powering modes of AC and DC, to realize frequency conversion equipment making full use of the direct current energy of public direct-current electrical network and regenerative resource generation.
For solving the problems of the technologies described above, the present invention is achieved by the following technical solutions:
A frequency conversion equipment supplied by AC/DC electricity system, is provided with DC power supply binding post, ac power supply terminal, direct current sample circuit, controller and for DC bus-bar voltage being reverse into the first inversion unit of the required Alternating Current Power Supply of AC load; Described ac power supply terminal sub-connection the first rectifier bridge, is rectified into the AC power of access by the first rectifier bridge the DC bus-bar voltage input of transmitting DC to the first inversion unit; Described DC power supply binding post connects the second inversion unit, by the second inversion unit, the DC power supply of access is reverse into AC power and transfers to after the isolated variable that isolating transformer carries out voltage, export the second rectifier bridge to and to be rectified into DC power supply, export the DC bus-bar voltage input of described the first inversion unit to; The collection of described direct current sample circuit is by the direct voltage of described DC power supply binding post input, and after isolating by DC-isolation converter, export described controller to, by controller, between two kinds of powering modes of AC and DC, carry out switching controls.
Selecting direct current supply pattern, be in the process of frequency conversion equipment power supply, in order to block the DC power supply output of the first rectifier bridge, the voltage magnitude of the DC power supply that setting of the present invention is exported by described the second rectifier bridge rectification is higher than the voltage peak of the AC power by the access of ac power supply terminal, thereby make the diode element in the first rectifier bridge anti-inclined to one side, cut off ac power supply line.
Further, whether the DC power supply that described controller accesses by DC power supply binding post according to the sampled voltage judgement of DC-isolation converter isolation output is normal, and described DC power supply detected when abnormal, control the second inversion unit out of service, turn by outside ac power supply, realize thus direct current supply to the seamless switching of Alternating Current Power Supply.
Further again, in described supplied by AC/DC electricity system, be also provided with alternating current sampling circuit, gather by the magnitude of voltage of the AC power of ac power supply terminal access, and transfer to described controller; Described controller, the DC power supply of access and AC power being detected when all abnormal, is controlled the first inversion unit and the second inversion unit out of service, cuts off the power supply to AC load, to protect AC load to avoid damaging.
In order to improve the power factor of frequency conversion equipment, between described the first rectifier bridge and the first inversion unit, be also connected with booster circuit, described booster circuit receives the pulse signal of controller output, and the direct current of the first rectifier bridge rectification output is carried out DC boosting conversion and alternating voltage, electric current are carried out to phasing; Described booster circuit transfers to the direct current after boosting the DC bus-bar voltage input of the first described inversion unit.
In order to realize the seamless switching from direct current supply to Alternating Current Power Supply, whether the DC power supply that described controller accesses by DC power supply binding post according to the sampled voltage judgement of DC-isolation converter output is normal, and detecting when abnormal, first control booster circuit and start operation, the conducting duty ratio that exports the pulse signal of booster circuit to is increased to required conducting duty ratio gradually since 0, and during this period, the conducting duty ratio that exports the pulse signal of the second inversion unit to is reduced gradually, until be 0, thereby it is out of service to control the second inversion unit, powering mode is switched seamlessly to Alternating Current Power Supply pattern by direct current supply pattern.Can realize thus DC bus-bar voltage and variable-frequency electric stream to seamlessly transit and not occur impact phenomenon.
In order to realize the seamless switching from Alternating Current Power Supply to direct current supply, described system operate in Alternating Current Power Supply pattern during in, if detecting the DC power supply accessing by DC power supply binding post, controller recovers normal, first controlling the second inversion unit puts into operation, the conducting duty ratio that exports the pulse signal of the second inversion unit to is increased to required conducting duty ratio gradually since 0, and during this period, the conducting duty ratio that exports the pulse signal of booster circuit to is reduced gradually, until be 0, thereby it is out of service to control booster circuit, powering mode is switched seamlessly to direct current supply pattern by Alternating Current Power Supply pattern.
Based on above-mentioned frequency conversion equipment supplied by AC/DC electricity system, the invention allows for a kind of transducer air conditioning that adopts described supplied by AC/DC electricity system, comprise DC power supply binding post, ac power supply terminal, direct current sample circuit, controller and for DC bus-bar voltage being reverse into the first inversion unit of the required Alternating Current Power Supply of AC load; Described ac power supply terminal sub-connection the first rectifier bridge, is rectified into transmitting DC to the DC bus-bar voltage input of described the first inversion unit by the first rectifier bridge by the AC power of access; Described DC power supply binding post connects the second inversion unit, by the second inversion unit, the DC power supply of access is reverse into AC power and transfers to after the isolated variable that isolating transformer carries out voltage, export the second rectifier bridge to and to be rectified into DC power supply, export the DC bus-bar voltage input of described the first inversion unit to; The collection of described direct current sample circuit is by the direct voltage of described DC power supply binding post input, and after isolating by DC-isolation converter, export described controller to, by controller, between two kinds of powering modes of AC and DC, carry out switching controls; Wherein, described AC load is the compressor in air conditioner; When air conditioner operates in Alternating Current Power Supply pattern, and more than design temperature and ambient temperature differ 5 ℃ and while needing the operation of compressor high frequency, if the direct voltage of exporting by the first rectifier bridge rectification is lower than meeting the needed DC bus-bar voltage of compressor operating frequency, keep existing DC bus-bar voltage constant, control compressor weak magnetic speed-up, realize required high frequency operation, fast ambient temperature is adjusted to design temperature.
Adopt the transducer air conditioning of above-mentioned supplied by AC/DC electricity system, its power factor is generally below 0.95.In order to improve the power factor of frequency-variable controller, it is reached more than 0.95, the invention allows for the supplied by AC/DC electricity system of another transducer air conditioning, comprise DC power supply binding post, ac power supply terminal, direct current sample circuit, controller and for DC bus-bar voltage being reverse into the first inversion unit of the required Alternating Current Power Supply of AC load; Described ac power supply terminal sub-connection the first rectifier bridge, by the first rectifier bridge, the AC power of access is rectified into transmitting DC to booster circuit, described booster circuit receives the pulse signal of controller output, and the direct current of the first rectifier bridge rectification output is carried out DC boosting conversion and alternating voltage, electric current are carried out to phasing; Described booster circuit transfers to the direct current after boosting the DC bus-bar voltage input of the first described inversion unit; Described DC power supply binding post connects the second inversion unit, by the second inversion unit, the DC power supply of access is reverse into AC power and transfers to after the isolated variable that isolating transformer carries out voltage, export the second rectifier bridge to and to be rectified into DC power supply, export the DC bus-bar voltage input of described the first inversion unit to; The collection of described direct current sample circuit is by the direct voltage of described DC power supply binding post input, and after isolating by DC-isolation converter, export described controller to, by controller, between two kinds of powering modes of AC and DC, carry out switching controls; Wherein, described AC load is the compressor in air conditioner.
In order to improve the stability of transducer air conditioning operation, when described transducer air conditioning operate in direct current supply pattern during in, if detecting the voltage magnitude of the DC power supply accessing by DC power supply binding post, controller drops to early warning line, now, if design temperature and ambient temperature differ more than 5 ℃, controller switches seamlessly to Alternating Current Power Supply pattern immediately; If design temperature and ambient temperature differ in 5 ℃, first control compression low-frequency operation, and the fluctuation situation of the DC power supply that detection accesses by DC power supply binding post in real time, if the voltage magnitude of the DC power supply of access continues to decline, lower than the lower limit of setting, controller switches seamlessly to Alternating Current Power Supply pattern immediately.
Compared with prior art, advantage of the present invention and good effect are mainly reflected in following several respects:
1, the present invention is by design supplied by AC/DC electricity system, make the frequency conversion equipments such as transducer air conditioning not only can directly use electric main power supply, the direct current energy that also can use public direct-current electrical network or regenerative resource to send is directly powered, for the frequency conversion equipment of the long-term continuous service of needs, can meet better undoubtedly its long-time work requirements running without interruption;
When 2, the present invention selects to switch between two kinds of powering modes of AC and DC, preferably adopting the direct current energy sending by regenerative resource is that equipment is powered, and only when DC power supply can not meet the power reguirements of equipment, just switch seamlessly to traditional Alternating Current Power Supply pattern, realize thus the utilization to greatest extent of regenerative resource, made frequency conversion equipment environmental protection and energy-conservation more;
3, the present invention by arranging isolating transformer in direct current supply line, and DC-isolation converter is set in direct current sample circuit, thereby make the power supply circuits of DC power supply realize electrical isolation completely with the power supply circuits that exchange city's net, avoided electric main to seal in DC power supply binding post, cause ac power supply line, by frequency converter and DC power supply, alternate short circuit occurs, and then cause the problem of frequency conversion equipment damage to occur, guaranteed device for electric safety;
The difference of the DC power supply that 4, the present invention can provide according to public direct-current electrical network or regenerative resource, the no-load voltage ratio of isolating transformer is carried out to suitable configuration, thereby adapt to the DC power supply that different public direct-current electrical networks or regenerative resource are sent, to expand the applicable situation of frequency conversion equipment.
Read by reference to the accompanying drawings after the detailed description of embodiment of the present invention, it is clearer that the other features and advantages of the invention will become.
Accompanying drawing explanation
Fig. 1 is the circuit theory diagrams that frequency conversion equipment proposed by the invention is used a kind of embodiment of supplied by AC/DC electricity system;
Fig. 2 is the circuit theory diagrams that frequency conversion equipment proposed by the invention is used another embodiment of supplied by AC/DC electricity system.
Embodiment
Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in detail.
The present invention can incoming transport and the brand-new powering mode of two kinds of power supplys of direct current in order to make frequency conversion equipment only support from the past that the single powering mode of tradition of Alternating Current Power Supply is transitioned into, on the basis of the ac power supply line of existing frequency conversion equipment, increase by a road direct current supply line, for receiving the DC power supply of sending by outside public direct-current electrical network or regenerative resource, thereby realized regenerative resource making full use of on frequency conversion equipment, made frequency conversion equipment energy-saving and environmental protection more.
Transducer air conditioning take below as example, by a specific embodiment, concrete assembling structure and the operation principle thereof of supplied by AC/DC electricity system proposed by the invention are described in detail.
Shown in Figure 1, the present embodiment arranges two groups of power supply terminals on transducer air conditioning: one group is for connecting the sub-X1 of ac power supply terminal, the X2 of electric main electrical network, and another group is for connecting DC power supply binding post X21, the X22 of public direct-current electrical network or the DC power supply sent of access regenerative resource.On the sub-X1 of described ac power supply terminal, X2, connect the first rectifier bridge A1, the single-phase full bridge rectification circuit being for example formed by connecting by four diodes, for the AC power by the sub-X1 of ac power supply terminal, X2 access is rectified into DC power supply, transfer to booster circuit, and then after the DC power supply of rectification output being carried out to DC boosting conversion by booster circuit and alternating voltage, current phase being proofreaied and correct, form DC bus-bar voltage, export the DC bus-bar voltage input of the first inversion unit to.Described the first inversion unit, for DC bus-bar voltage is reverse into the alternating voltage that AC load is moved required frequency, is AC load power supply in transducer air conditioning.
In the present embodiment, described AC load can specifically refer to the compressor M in transducer air conditioning.Because selected compressor M in current transducer air conditioning needs three-phase alternating-current powered mostly, therefore, when design the first inversion unit, should select six semiconductor switch device V11-V16(such as six IGBT high-power switch tubes etc.) be connected to form three-phase inverting circuit, so that DC bus-bar voltage is reverse into three-phase alternating voltage, it is the three phase alternating current motor power supply in compressor M.
In order to control compressor M converting operation, the control end of six semiconductor switch device V11-V16 (for example grid of IGBT high-power switch tube) is connected to controller D1, and described controller D1 can select a micro-chip processor MCU accurately to control the switching sequence of each semiconductor switch device V11-V16 in three-phase inverting circuit.A kind of preferred design as the present embodiment, described controller D1 is according to the design temperature of air conditioner and current ambient temperature, calculate the operating frequency of compressor M, and then according to the pwm signal of the operating frequency generation suitable duty ratio calculating, export the control end of six semiconductor switch device V11-V16 to, by controlling the break-make sequential of each semiconductor switch device V11-V16, with inversion, generate the three-phase alternating-current supply of required frequency, export compressor M to, and then realize the adjusting to compressor M operating frequency.
For described booster circuit, the present embodiment preferably adopts a semiconductor switch pipe V1 to coordinate inductance L 1 and diode V2 to be formed by connecting, shown in Figure 1.The present embodiment be take high-power IGBT pipe and is described as example as described semiconductor switch pipe V1.Described inductance L 1 is connected between the positive pole and the anode of diode V2 of the first rectifier bridge A1 direct current outlet side, the negative electrode of diode V2 connects the DC bus-bar voltage input of the first inversion unit, and by electrochemical capacitor C1 ground connection.The grid of high-power IGBT pipe V1 is connected to controller D1, receive the control signal (for example pulse signal) of controller D1 output, collector electrode connects the anode of diode V2, grounded emitter.Controller D1 requires according to the amplitude of the required DC bus-bar voltage of the first inversion unit and the demand to AC power power factor, generate the output of pulse signal of corresponding duty ratio to the grid of high-power IGBT pipe V1, by controlling the switching frequency of high-power IGBT pipe V1 and the phase relation of alternating voltage, thereby the DC power supply boosting inverter by the first rectifier bridge A1 rectification output is become to the required DC bus-bar voltage of the first inversion unit, approximately about 400V, to meet the power demands of the first inversion unit.
DC bus-bar voltage input at the first inversion unit is also connected with sample circuit, specifically can adopt two divider resistance R3, R4 to be connected between DC bus-bar voltage input, the intermediate node of divider resistance R3, R4 is connected to controller D1, utilize the DC bus-bar voltage that two divider resistance R3, R4 receive the first inversion unit to carry out after dividing potential drop, Vdc is to controller D1 for output partial pressure value, and then realizes the sampling of controller D1 to DC bus-bar voltage.Controller D1 is according to the sampled value Vdc of the DC bus-bar voltage receiving, converse actual DC bus-bar voltage amplitude, and then by regulating the IGBT pipe switching frequency of V1 and the phase relation of alternating voltage, the DC bus-bar voltage of exporting by booster circuit can be stabilized in the desired amplitude of the first inversion unit.
In order to make transducer air conditioning can receive the direct current supply that outside public direct-current electrical network or regenerative resource provide, to reduce the use to electric main, the present embodiment is also provided with the second inversion unit, isolating transformer T21 and the second rectifier bridge A2 on the power panel of transducer air conditioning, shown in Figure 1.Described the second inversion unit is connected to DC power supply binding post X21, X22, receive by the direct current supply of DC power supply binding post X21, X22 access, and be reverse into AC power and export isolating transformer T21 to, and then isolated variable becomes high-voltage ac power to transfer to the second rectifier bridge A2.Described the second rectifier bridge A2 is rectified into high-voltage DC power supply (greatly about 400V left and right) by the high-voltage ac power of isolating transformer T21 conversion output, exports the first inversion unit to, for the first inversion unit provides DC bus-bar voltage.
In the present embodiment, described the second inversion unit preferably adopts four semiconductor switch device V21-V24 to connect into single-phase inversion circuit, for the DC power supply by DC power supply binding post X21, X22 access is reverse into single phase alternating current power supply, export the former limit of isolating transformer T21 to.Described four semiconductor switch device V21-V24 can select IGBT high-power switch tube to carry out circuit design, as shown in Figure 1.The control end of four semiconductor switch device V21-V24 (for example grid of IGBT high-power switch tube) is connected to controller D1, receive the pulse signal that controller D1 sends, by the switch conduction duty ratio to four semiconductor switch device V21-V24, control, to regulate the effective value of the alternating voltage of exporting by its inversion.
By the AC of secondary connection the second rectifier bridge A2 of described isolating transformer T21, by regulating the no-load voltage ratio of isolating transformer T21, can change by the effective value of the alternating voltage of isolating transformer T21 conversion output, and then with rectification, export the required DC bus-bar voltage of the first inversion unit by the second rectifier bridge A2.
The present embodiment by adopting isolating transformer T21 in direct current supply line, can make DC power-supply circuit and ac power circuit electrical isolation on the one hand, avoid Alternating Current Power Supply to import DC power supply binding post X21, X22 into, cause ac power supply line by frequency converter and DC power supply generation phase fault; On the other hand can be by regulating the no-load voltage ratio of isolating transformer T21, make transducer air conditioning go for the direct current supply that different public direct-current electrical networks or regenerative resource are sent.
In order to meet the selection of transducer air conditioning between two kinds of powering modes, switch requirement, the present embodiment is provided with respectively sample circuit at the sub-X1 of described ac power supply terminal, X2 and DC power supply binding post X21, X22 two ends, shown in Figure 1.Wherein, direct current sample circuit can adopt two divider resistance R21, R22 to be formed by connecting, and coordinates DC-isolation converter A21 to complete the voltage sample to the DC power supply by DC power supply binding post X21, X22 access.Concrete annexation is preferably: first, by after two divider resistance R21, R22 series connection, be connected to the two ends of DC power supply binding post X21, X22; Then the intermediate node of divider resistance R21, R22 is connected to input+IN of DC-isolation converter A21, the output of DC-isolation converter A21+Vo connects controller D1.When having DC power supply access by DC power supply binding post X21, X22, divider resistance R21, R22 carry out dividing potential drop to the direct voltage of access, Vi is to DC-isolation converter A21 for output partial pressure value, carry out after the isolated variable processing of DC-to-DC, be sent to described controller D1, the voltage sample of realization to input DC power, and then complete the whether abnormal real-time detection of DC power supply to input.
The present embodiment by arranging isolating transformer T21 in direct current supply line, DC-isolation converter A21 is set in direct current sample circuit, thus make regenerative resource power supply circuits (or public direct-current electrical network circuit) can with the complete electrical isolation of electrical network circuit of electric main.So,, in the time of not only can avoiding any one electrode grounding in the power supply circuits of regenerative resource, cause the problem of city's net alternating current and regenerative resource power supply circuit shorted to earth, and, even if there is no electrode grounding in the power supply circuits of regenerative resource, also can effectively avoid the hot voltage of city's net alternating current to seal in two DC electrode in regenerative resource power supply circuit, thereby the supply line of the Danger Electric shock risk causing and regenerative resource, the infringement that equipment brings because bearing the hot voltage of city's net alternating current, significantly improved the fail safe of other electric equipment operations in transducer air conditioning and user family, and for a plurality of families, use the situation of this system, if each family use three-phase alternating-current supply homophase is not powered time, can also avoid occurring forming by frequency conversion system and direct current network the phase fault problem of three phase mains.
Phase place realization detection for and alternating voltage whether abnormal to the alternating voltage of AC network, the present embodiment connects alternating current sampling circuit at the two ends of AC power access terminal X1, X2, as shown in Figure 1, mainly by operational amplifier N1, reference power source VREF, coordinate peripheral resistance to be formed by connecting.Wherein, the in-phase input end of the live wire X1 of AC power access terminal by resistance R 1 concatenation operation amplifier N1+, the in-phase input end of described operational amplifier N1+simultaneously by the intermediate node of resistance R 12 connection divider resistance R13, R14, described divider resistance R13, R14 are connected between reference power source VREF and ground, reference power source VREF is carried out after dividing potential drop, for the alternating voltage on live wire provides DC offset voltage.The inverting input of the zero line X2 of AC power access terminal by resistance R 2 concatenation operation amplifier N1-, the inverting input of described operational amplifier N1-connect by the feedback resistance R11 output of himself, by output output AC sampled voltage Vac, transfer to described controller D1, the voltage sample of realization to alternating current input power supplying, and then complete the whether abnormal real-time detection of the AC power of input and the phase-detection of alternating voltage.
The present embodiment utilizes controller D1 to detect direct voltage, the alternating voltage of inputting by utility grid, the phase place of alternating voltage and the DC bus-bar voltage that inputs to the first inversion unit of inputting by regenerative resource, and by computing and the logical process of controller D1, output pulse control signal, the semiconductor switch device of controlling in the first inversion unit, the second inversion unit and booster circuit is opened or is turn-offed, and then realizing DC power supply in regenerative resource output when normal, the DC power supply of being exported by regenerative resource is that transducer air conditioning is powered; When the DC power supply of regenerative resource output can not normal power supply, if city's net alternating current is normal, Ze Zhuanyou city net alternating current provides electric energy; In the process of city's net AC-powered, if the DC power supply of regenerative resource output detected, recover normal, again switch back regenerative resource power supply; If when regenerative resource and city's net alternating current all can not normal power supplies, control transducer air conditioning out of service.The present embodiment be take Alternating Current Power Supply that the direct current supply of regenerative resource is main, utility grid as auxiliary by the powering mode of design transducer air conditioning, thereby has realized to greatest extent the effective use of regenerative resource, makes transducer air conditioning environmental protection more, energy-conservation.
Below in conjunction with Fig. 1, the specific works principle of the supplied by AC/DC electricity system of the present embodiment is at length set forth.
First, according to the no-load voltage ratio situation of the inversion characteristic of the actual working characteristics of compressor in transducer air conditioning and the second inversion unit and isolating transformer T21, determine the voltage range that can meet the required direct current supply of the normal operation of compressor, writing controller D1.
Controller D1 during transducer air conditioning operation in, by direct current sample circuit, detect in real time direct voltage by DC power supply binding post X21, X22 input whether in the normal range (NR) in setting.If direct voltage is normal, enable direct current supply pattern, that is, controller D1 outputs control signals to the second inversion unit, controls the second inversion unit and starts operation, and turn-off the semiconductor switch pipe V1 in booster circuit.Controller D1 is by regulating the conducting duty ratio of each semiconductor switch device V21-V24 in the second inversion unit, make the alternating impulse power square wave of the former limit acquisition required pulse width of isolating transformer T21, through isolating transformer T21, isolate after transformation again, export the second rectifier bridge A2 to ac voltage rectifier is become to direct voltage, export the first inversion unit to, for the first inversion unit provides its work required DC bus-bar voltage.Controller D1 is according to the difference of the design temperature of transducer air conditioning and actual environment temperature, calculate the required operating frequency of compressor, and then according to the conducting duty ratio of each semiconductor switch device V11-V16 in this frequency adjustment first inversion unit, control the first inversion unit and DC bus-bar voltage is reverse into the AC power of the required frequency of compressor operating, export the power supply terminal of compressor to, the operation of drive compression machine.
The amplitude of the direct voltage of exporting by the second rectifier bridge A2 rectification in the present embodiment, should be greater than the waveform peak that accesses the alternating voltage of terminal X1, X2 access by AC power.Due to transducer air conditioning be operated in direct current supply pattern during in, controller D1 does not provide conducting pulse to the semiconductor switch pipe V1 in booster circuit, so booster circuit is not to the effect of alternating current input power supplying raising voltage, therefore diode V2 bears reversed bias voltage all the time.Like this, the DC power supply of just only having input provides DC bus-bar voltage for the first inverter circuit, avoids the use of Liao Dui city net alternating current.
Because the DC power supply providing for transducer air conditioning can be provided by regenerative resource, therefore make the operation environmental protection more of transducer air conditioning.
When controller D1 detects direct voltage by DC power supply binding post X21, X22 input and is reduced to early warning line (the corresponding magnitude of voltage of described early warning line still the normal range (NR) in setting in), first judge whether the design temperature of air conditioner and current ambient temperature differ larger, take 5 ℃ as critical value as example, describe.If design temperature and current ambient temperature are more or less the same, for example differ in 5 ℃, if now the running frequency of compressor M is lower, can controls compressor M and keep current operating frequency to continue operation; If the running frequency of compressor M is higher, first control compressor M low-frequency operation, its running frequency preferably≤30Hz, and observe by the fluctuation situation of the direct voltage of DC power supply binding post X21, X22 input simultaneously.If the direct voltage of input no longer reduces, can maintain current direct current supply pattern; If the direct voltage of input continues to decline, exceeded the lower limit of normal range (NR), should be switched to immediately Alternating Current Power Supply pattern, to guarantee that compressor M can continuous service.If the direct voltage by DC power supply binding post X21, X22 input is reduced to early warning line, and now the design temperature of air conditioner and current ambient temperature differ again larger, in the time of for example, more than differing 5 ℃, due to when design temperature and ambient temperature differ larger, for the temperature that controls environment can approach rapidly design temperature, need the operation of compressor M high frequency.In this case, in order to guarantee the continuous operation of air conditioner, need to immediately powering mode be switched to Alternating Current Power Supply pattern, the power demands while moving to meet compressor M high frequency.
In the process that powering mode is switched to Alternating Current Power Supply pattern by direct current supply pattern, in order to realize the seamless switching of two kinds of power supplies, the present embodiment is first to carrying out sample detecting by the AC power of the sub-X1 of ac power supply terminal, X2 input.If the AC power of input is normal, controller D1 first output pulse signal to semiconductor switch pipe V1, control booster circuit and start operation, the conducting duty ratio that exports the pulse signal of booster circuit to is increased to required conducting duty ratio gradually since 0, and during this period, controller D1 reduces the conducting duty ratio that exports the pulse signal of the second inversion unit to gradually, until be 0, thereby it is out of service to control the second inversion unit, cut off the input of DC power supply, realize the seamless switching of supply power mode from direct current supply pattern to Alternating Current Power Supply pattern.
When air conditioner operates in Alternating Current Power Supply pattern lower time, the first rectifier bridge A1 is rectified into DC power supply by the AC power by the sub-X1 of ac power supply terminal, X2 input, export booster circuit to, boosting inverter becomes the required DC bus-bar voltage of the first inversion unit work, export the DC bus-bar voltage input of the first inversion unit to, and then generate by the first inversion unit inversion the three-phase alternating-current supply that compressor M moves required frequency, be compressor M power supply.
Transducer air conditioning operate in Alternating Current Power Supply pattern during in, controller D1 in real time to by DC power supply binding post X21, X22 input DC power supply carry out sample detecting.If the DC power supply of input being detected comes back in normal range (NR), first start the second inversion unit, to each semiconductor switch device V21-V24 transmitted signal in the second inversion unit, the conducting duty ratio of controlling described pulse signal since 0 be increased to gradually required conducting duty ratio during in, the conducting duty ratio that exports the switching pulse signal of semiconductor switch pipe V1 in booster circuit to is reduced gradually simultaneously, until be 0, thereby it is out of service to control booster circuit, then realize the seamless switching of supply power mode from Alternating Current Power Supply pattern to direct current supply pattern.
When controller D1 detects the AC power of input and DC power supply when undesired; block immediately the pulse signal that exports each semiconductor switch device V11-V16, V21-V24, V1 to; control the first inversion unit, the second inversion unit and booster circuit out of service, to protect the safety of compressor M.
The present embodiment adopts above-mentioned power supply control strategy, in during making that transducer air conditioning can normal power supply in regenerative resource, the DC power supply of using regenerative resource to send is completely powered, and only when DC power supply is abnormal, just turn by traditional electric main mains supply, not only meet thus the requirement of transducer air conditioning long-time continuous operation, and realized the utilization to greatest extent to regenerative resource.
Above-mentioned supplied by AC/DC electricity system is owing to having used booster circuit in ac power supply line, therefore, when air conditioner operates in Alternating Current Power Supply pattern, according to the phase place of alternating voltage, semiconductor switch pipe V1 is sent to voltage boosting pulse, its power factor can reach more than 0.95.The transducer air conditioning that is less than 0.95 for current power factor, owing to not using booster circuit in its ac power supply line, therefore,, when introducing the design of direct current supply line shown in Fig. 1 in this class transducer air conditioning, need to adjust accordingly its control strategy.
Specifically, when design power factor is less than 0.95 transducer air conditioning, AC power by the sub-X1 of ac power supply terminal, X2 access is undertaken after rectifying conversion by the first rectifier bridge A1, after electrochemical capacitor C1 filtering, directly export the first inversion unit to, for the first inversion unit provides DC bus-bar voltage.Owing to there is no the DC boosting effect of booster circuit, therefore, when adopting electric main mains supply, offer the DC bus-bar voltage of the first inversion unit approximately only in 300V left and right.Same design direct current supply line as shown in Figure 1 on the power panel of such transducer air conditioning, comprise DC power supply binding post X21, X22, the second inversion unit, isolating transformer T21 and the second rectifier bridge A2, shown in Figure 2, after DC power supply to outside input is carried out successively inversion, is boosted, rectification processes, export the direct voltage of about 400V left and right, for the first inversion unit provides its work required DC bus-bar voltage.
The direct voltage that regenerative resource output detected by direct current sample circuit as controller D1 is in normal range (NR) time, control the second inversion unit and start operation, and by regulating the conducting duty ratio of semiconductor switch device V21-V24, while making direct voltage by the second rectifier bridge A2 rectification output reach the operation of compressor M high frequency, the amplitude of the DC bus-bar voltage that the first inversion unit work is required.Now, due to the amplitude of the DC bus-bar voltage by the second rectifier bridge A2 rectification output peak value higher than city's net alternating voltage waveform, therefore, make the diode in the first rectifier bridge A1 bear reversed bias voltage all the time and end.So, just only have the DC power supply of input for the first inversion unit provides DC bus-bar voltage, just reduced thus the consumption of air conditioner to city's net alternating current.
When controller D1 detects direct voltage by DC power supply binding post X21, X22 access while dropping to early warning line, judge that whether the design temperature of transducer air conditioning and the difference of current environmental temperature larger, still take 5 ℃ describe as example.If design temperature and current environmental temperature differ more than 5 ℃, and transducer air conditioning needs high frequency operation, now, the operation of transducer air conditioning can further drag down the current potential of DC power supply, therefore, the conducting pulse duty factor that controller D1 controls the second inversion unit is immediately reduced to 0 and out of service gradually, switches seamlessly to Alternating Current Power Supply pattern, to guarantee normally continuous service of air conditioner.If design temperature and current environmental temperature differ less, for example, in 5 ℃, maintain the current operating frequency of air conditioner and continue operation, and whether the direct voltage that continues to observe input continues to decline.If the direct voltage of input continues to drop to the lower limit of safe range, controller D1 switches seamlessly to Alternating Current Power Supply pattern immediately, adopts city's net alternating current to continue as air conditioner power supply.
When air conditioner operate in Alternating Current Power Supply pattern during in, owing to offering by ac power supply line, the DC bus-bar voltage of the first inversion unit is lower, may not meet the high frequency service requirement of compressor, thereby the following control strategy of the present embodiment design:
Controller D1 detects the design temperature of air conditioner and the difference of current environmental temperature, if be more or less the same, for example, in 5 ℃,, by the first inversion unit control compressor M low-frequency operation, makes ambient temperature slowly approach design temperature.Now, the DC bus-bar voltage by the first rectifier bridge A1 output just can meet the job requirement of the first inversion unit completely.When design temperature and current environmental temperature differ larger, for example difference is more than or equal to 5 ℃, now needs the operation of compressor M high frequency.While moving due to compressor M high frequency, need to provide higher DC bus-bar voltage to the first inversion unit, now just there will be the situation that can not meet the required DC bus-bar voltage of the first inversion unit by the direct voltage of the first rectifier bridge A1 output.In order to meet the requirement of compressor M high frequency operation, the present embodiment adopts weak magnetic speed-up technology, utilize controller D1 to detect the induced potential of compressor M, by operation FOC algorithm, calculate the angle between the back electromotive force of permanent magnet synchronous motor in time that provides of the pwm pulse that is applied to the first inversion unit and compressor M, by weakening the magnetic field of permanent magnet in motor, make motor produce weak magnetic speed-up, realize high frequency running, the service requirement that meets air conditioner fast-refrigerating or heat.
When air conditioner operate in Alternating Current Power Supply pattern during in, if detecting the DC power supply of regenerative resource output, controller D1 recovers normal, switch seamlessly to direct current supply pattern, continuing to adopt the regenerative resource of environmental protection is transducer air conditioning power supply, to save to greatest extent electric main.
Although the APFC that the supplied by AC/DC electricity system shown in Fig. 2 does not have booster circuit to form, it adopted equally take regenerative resource direct current supply as main, city's net Alternating Current Power Supply be that auxiliary energy-conservation power supply is tactful.
Certainly, the circuit design of the supplied by AC/DC electricity system that the present embodiment proposes, except being applied in transducer air conditioning, realizes the green energy conservation of transducer air conditioning, and applicable equally for other frequency conversion equipments, and the present embodiment does not specifically limit this.
It should be noted that; the above is only a kind of preferred implementation of the present invention, for those skilled in the art, and under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (10)

1. a frequency conversion equipment supplied by AC/DC electricity system, is characterized in that: be provided with DC power supply binding post, ac power supply terminal, direct current sample circuit, controller and for DC bus-bar voltage being reverse into the first inversion unit of the required Alternating Current Power Supply of AC load; Described ac power supply terminal sub-connection the first rectifier bridge, is rectified into the AC power of access by the first rectifier bridge the DC bus-bar voltage input of transmitting DC to the first inversion unit; Described DC power supply binding post connects the second inversion unit, by the second inversion unit, the DC power supply of access is reverse into AC power and transfers to after the isolated variable that isolating transformer carries out voltage, export the second rectifier bridge to and to be rectified into DC power supply, export the DC bus-bar voltage input of described the first inversion unit to; The collection of described direct current sample circuit is by the direct voltage of described DC power supply binding post input, and after isolating by DC-isolation converter, export described controller to, by controller, between two kinds of powering modes of AC and DC, carry out switching controls.
2. frequency conversion equipment according to claim 1 supplied by AC/DC electricity system, is characterized in that: the voltage magnitude of the DC power supply of exporting by described the second rectifier bridge rectification is higher than the voltage peak of the AC power by the access of ac power supply terminal.
3. frequency conversion equipment according to claim 2 supplied by AC/DC electricity system, it is characterized in that: whether the DC power supply that described controller accesses by DC power supply binding post according to the sampled voltage judgement of DC-isolation converter isolation output is normal, and detecting when abnormal, control the second inversion unit out of service, turn by outside ac power supply.
4. frequency conversion equipment according to claim 3 supplied by AC/DC electricity system, it is characterized in that: in described supplied by AC/DC electricity system, be also provided with alternating current sampling circuit, gather by the magnitude of voltage of the AC power of ac power supply terminal access, and transfer to described controller; Described controller, the DC power supply of access and AC power being detected when all abnormal, is controlled the first inversion unit and the second inversion unit out of service, cuts off the power supply to AC load.
5. frequency conversion equipment according to claim 1 and 2 supplied by AC/DC electricity system, it is characterized in that: between described the first rectifier bridge and the first inversion unit, be also connected with booster circuit, described booster circuit receives the pulse signal of controller output, and the direct current of the first rectifier bridge rectification output is carried out DC boosting conversion and alternating voltage, electric current are carried out to phasing; Described booster circuit transfers to the direct current after boosting the DC bus-bar voltage input of the first described inversion unit.
6. frequency conversion equipment according to claim 5 supplied by AC/DC electricity system, it is characterized in that: whether the DC power supply that described controller accesses by DC power supply binding post according to the sampled voltage judgement of DC-isolation converter output is normal, and detecting when abnormal, first control booster circuit and start operation, the conducting duty ratio that exports the pulse signal of booster circuit to is increased to required conducting duty ratio gradually since 0, and during this period, the conducting duty ratio that exports the pulse signal of the second inversion unit to is reduced gradually, until be 0, thereby it is out of service to control the second inversion unit, powering mode is switched seamlessly to Alternating Current Power Supply pattern by direct current supply pattern.
7. frequency conversion equipment according to claim 6 supplied by AC/DC electricity system, it is characterized in that: described system operate in Alternating Current Power Supply pattern during in, if detecting the DC power supply accessing by DC power supply binding post, controller recovers normal, first controlling the second inversion unit puts into operation, the conducting duty ratio that exports the pulse signal of the second inversion unit to is increased to required conducting duty ratio gradually since 0, and during this period, the conducting duty ratio that exports the pulse signal of booster circuit to is reduced gradually, until be 0, thereby it is out of service to control booster circuit, powering mode is switched seamlessly to direct current supply pattern by Alternating Current Power Supply pattern.
8. a transducer air conditioning, is characterized in that: be provided with the frequency conversion equipment supplied by AC/DC electricity system as described in any one claim in claim 1 to 4; Described AC load is the compressor in air conditioner; When air conditioner operates in Alternating Current Power Supply pattern, and more than design temperature and ambient temperature differ 5 ℃ and while needing the operation of compressor high frequency, if the direct voltage of exporting by the first rectifier bridge rectification is lower than meeting the needed DC bus-bar voltage of compressor operating frequency, keep existing DC bus-bar voltage constant, control compressor weak magnetic speed-up, realize required high frequency operation.
9. a transducer air conditioning, is characterized in that: be provided with the frequency conversion equipment supplied by AC/DC electricity system as described in any one claim in claim 5 to 7; Described AC load is the compressor in air conditioner.
10. transducer air conditioning according to claim 9, it is characterized in that: described transducer air conditioning operate in direct current supply pattern during in, the voltage magnitude that the DC power supply accessing by DC power supply binding post detected when controller drops to early warning line, now, if design temperature and ambient temperature differ more than 5 ℃, controller switches seamlessly to Alternating Current Power Supply pattern immediately; If design temperature and ambient temperature differ in 5 ℃, first control compressor low-frequency operation, and the fluctuation situation of the DC power supply that detection accesses by DC power supply binding post in real time, if the voltage magnitude of the DC power supply of access continues to decline, lower than the lower limit of setting, controller switches seamlessly to Alternating Current Power Supply pattern immediately.
CN201310634848.5A 2013-12-03 2013-12-03 Frequency conversion equipment supplied by AC/DC electricity system and transducer air conditioning Expired - Fee Related CN103701309B (en)

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CN108233719A (en) * 2018-02-01 2018-06-29 湖南意谱电动系统有限公司 A kind of llc circuits that can adapt to wide output voltage range and control method
CN110149083A (en) * 2018-02-12 2019-08-20 西安中车永电捷通电气有限公司 Inversion major loop and permanent magnet synchronous motor transmission system
CN110203040A (en) * 2019-07-01 2019-09-06 合肥天鹅制冷科技有限公司 The control system of double-standard dual system air-conditioning
CN110707990A (en) * 2019-10-16 2020-01-17 合肥学院 AC/DC motor control system
CN111720947A (en) * 2020-06-19 2020-09-29 海信(山东)空调有限公司 Method for controlling bus voltage of air conditioner, air conditioner and storage medium
CN112398329A (en) * 2019-08-14 2021-02-23 台达电子工业股份有限公司 Bidirectional power factor correction module

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CN108027159A (en) * 2015-09-18 2018-05-11 夏普株式会社 The control method of air conditioner and air conditioner
CN108027159B (en) * 2015-09-18 2020-11-10 夏普株式会社 Air conditioner and control method for air conditioner
CN105629190B (en) * 2016-01-27 2019-01-15 中车株洲电力机车有限公司 A kind of alternating current-direct current network pressure detection circuit
CN105629190A (en) * 2016-01-27 2016-06-01 中车株洲电力机车有限公司 AC/DC network voltage detection circuit
CN105510680A (en) * 2016-01-27 2016-04-20 中车株洲电力机车有限公司 Alternating current and direct current net voltage detection device
CN107395090A (en) * 2017-06-22 2017-11-24 东南大学 A kind of high-power High Power Factor drive control device for single-phase linear Stirling motor
CN107959458A (en) * 2017-12-06 2018-04-24 海信(山东)空调有限公司 Dc bus low capacity capacitance frequency conversion control circuit and frequency conversion equipment
CN108233719A (en) * 2018-02-01 2018-06-29 湖南意谱电动系统有限公司 A kind of llc circuits that can adapt to wide output voltage range and control method
CN110149083A (en) * 2018-02-12 2019-08-20 西安中车永电捷通电气有限公司 Inversion major loop and permanent magnet synchronous motor transmission system
CN110203040A (en) * 2019-07-01 2019-09-06 合肥天鹅制冷科技有限公司 The control system of double-standard dual system air-conditioning
CN110203040B (en) * 2019-07-01 2024-01-12 合肥天鹅制冷科技有限公司 Control system of double-system air conditioner
CN112398329A (en) * 2019-08-14 2021-02-23 台达电子工业股份有限公司 Bidirectional power factor correction module
CN112398329B (en) * 2019-08-14 2021-08-31 台达电子工业股份有限公司 Bidirectional power factor correction module
CN110707990A (en) * 2019-10-16 2020-01-17 合肥学院 AC/DC motor control system
CN111720947A (en) * 2020-06-19 2020-09-29 海信(山东)空调有限公司 Method for controlling bus voltage of air conditioner, air conditioner and storage medium

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