CN103795323A - High-voltage frequency-conversion speed-regulation system and control method thereof - Google Patents
High-voltage frequency-conversion speed-regulation system and control method thereof Download PDFInfo
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- CN103795323A CN103795323A CN201210435122.4A CN201210435122A CN103795323A CN 103795323 A CN103795323 A CN 103795323A CN 201210435122 A CN201210435122 A CN 201210435122A CN 103795323 A CN103795323 A CN 103795323A
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Abstract
The invention discloses a high-voltage frequency-conversion speed-regulation system and a control method thereof. The system includes a phase-shifting transformer, a frequency converter which includes 3n identical power units, optical-fiber interfaces and a control unit, wherein n is larger than or equal to 2 and is an integer. Every n power units are connected serially and sequentially into one phase and the power units are connected with a motor after being connected in a three-phase star-type manner. The phase-shifting transformer includes 3n secondary windings. Each secondary winding is connected with a power unit. The control unit is connected with the different power units through the optical-fiber interfaces. The method includes: an initializing step; an interrupt-vector-table updating step; a watchdog starting step; and a PWM interrupt repeating step. Through a multi-level PWM control method and realizes, the high-voltage frequency-conversion speed-regulation system and the control method thereof provide sine-wave current output and realize high-quality control of the motor. The control method enables the high-voltage frequency-conversion speed-regulation system to operate in an efficient, accurate and orderly manner so that high efficiency, high power factor and high reliability are realized.
Description
Technical field
The present invention relates to a kind of high-voltage variable-frequency and variable-speed system and control method thereof.
Background technology
Along with promotion and China's high-tension motor capacity rapid growth of national energy-saving reduction of discharging policy, high voltage converter market has welcome the fast-developing phase.Frequency converter is installed between power supply and motor, automatically regulate the speed of service of motor by changing frequency and output voltage, improving the operational efficiency of user electric motor system and the object of electrical energy saving thereby reach, is the most desirable, the most promising motor energy-saving device at present.High voltage converter belongs to great electrical equipment, is the high, precision and frontier product in frequency converter, is mainly used in driving, the energy-saving run of high-voltage motor and the improvement of processing performance of key equipment, is widely used in electric power, metallurgy, petrochemical industry, locomotive traction etc.
The variation of topological structure and control method is the feature of high voltage converter; In numerous topological structures, all have such as friendship-ac frequency converter, GTO current source type frequency converter, three-level voltage source type frequency converter, power device series connection direct voltage two power level voltage source type frequency converters etc. that input side harmonic wave is large, output harmonic wave large and the high deficiency of output voltage rate of change.Compared with these topological structure inverters, units in series multi-electrical level inverter has the features such as harmonic wave is little, common-mode voltage is little, voltage change ratio is little, electromagnetic interference is little, switching frequency is low, system effectiveness is high, applicable mesohigh large-capacity transducer application.Therefore, the multiple-level serially connected high-voltage AC motor frequency conversion speed-adjusting system of development block is also applied, and China's industry is reduced to per unit area yield energy consumption and be significant, be also the direction that the applicant is devoted to research always.
Summary of the invention
The object of the present invention is to provide the high-voltage variable-frequency and variable-speed system of the many level-types of a kind of units in series, by many level PWMs (pulse width modulation) control mode, sine-wave current output is provided, realize the high-quality control to motor, significantly saves energy, and the real time monitoring function having has guaranteed its normal operation, thereby the high efficiency of realization, high power factor and high reliability.
The present invention also aims to provide the control method of this high-voltage variable-frequency and variable-speed system.
The technical scheme that realizes above-mentioned purpose is:
One of the present invention's high-voltage variable-frequency and variable-speed system, is connected between three phase mains and motor, and this high-voltage variable-frequency and variable-speed system comprises phase shifting transformer, frequency converter, optical fiber interface and control unit, wherein:
Frequency converter, comprises 3n identical power cell, and n >=2 and n are integer; Every n power cell is followed in series to form a phase, the star-like rear described motor that connects that is connected of three-phase;
Phase shifting transformer, comprises former limit winding and 3n secondary winding, and former limit winding connects described three phase mains, and each secondary winding all connects a power cell according to extend-triangle connection;
Control unit, connects each power cell by described optical fiber interface, controls concurrently each power cell, and the running status of real time monitoring frequency converter and each power cell.
Above-mentioned high-voltage variable-frequency and variable-speed system, wherein, described control unit comprises interconnective DSP(Digital Signal Processing) chip and FPGA(field programmable gate array) chip, fpga chip connects each power cell by described optical fiber interface.
Above-mentioned high-voltage variable-frequency and variable-speed system, wherein, described power cell comprises a protection bypass, for this power unit by-pass when breaking down.
Above-mentioned high-voltage variable-frequency and variable-speed system, wherein, described high-voltage variable-frequency and variable-speed system also comprises the touch-screen of the described control unit of a connection, for realizing man-machine interaction.
Above-mentioned high-voltage variable-frequency and variable-speed system, wherein, described n is 6.
The present invention's two the control method based on above-mentioned high-voltage variable-frequency and variable-speed system, comprises the following steps:
Step S1, control unit described in initialization;
Step S2, upgrades interrupt vector table;
Step S3, opens house dog;
Step S4, open PWM interrupt process, shown in interrupt vector table, described control unit gathers the information of a power cell and the input/output information of frequency converter, analyze and process alarm condition and malfunction, in the time of alarm free, fault or eliminating, report to the police, after fault, calculate PWM duty ratio and send to the power cell of current controlled unit Information Monitoring, then feed dog, repeating step S4 to house dog.
Above-mentioned control method, wherein, described step S4 comprises the following steps:
Step S401, whether detection alarm, failure reset flag bit be effective, as effectively, enters step S402; As invalid, enter step S403;
Step S402, warning, failure reset flag bit reset;
Step S403, according to interrupt vector table, determines the power cell of the Information Monitoring of wanting;
Step S404, busbar voltage, output voltage and the communication state of the determined power cell of acquisition step S403, analyze alarm condition and the malfunction of this power cell;
Step S405, input current, output current and the output voltage of collection frequency converter, carry out digital filtering, obtains each digital signal;
Step S406, the each digital signal obtaining in read step S405, alarm condition and the malfunction of analysis frequency converter;
Step S407, for alarm condition and the malfunction of frequency converter in the alarm condition of power cell in step S404 and malfunction and step S406, reports to the police or fault if existed, and moves corresponding processing instruction, and enters step S408; If there is no report to the police or fault, enter step S409;
Step S408, whether the processing instruction that detects operation is effective, if effectively, enter step S409; If invalid, enter step S410;
Step S409, calculates the PWM duty ratio for controlling the determined power cell of step S403 and is transferred to this power cell;
Step S410, house dog feeds dog, then enters step S401.
The invention has the beneficial effects as follows: one of the present invention's high-voltage variable-frequency and variable-speed system adopts multiple power cells to form the topological structure of multiplex series connection, each power cell is powered by one group of secondary of phase shifting transformer respectively, secondary winding adopts extend-triangle connection, thereby reaches the object that reduces Harmonics of Input; And high-voltage variable-frequency and variable-speed system adopts many level PWMs control mode, provide sine-wave current output, reduce output harmonic wave, the electric motor overheating, noise and the torque pulsation that are caused by harmonic wave are all reduced greatly, thereby realize the high-quality control to motor, significantly saves energy; And; high-voltage variable-frequency and variable-speed system has the function of the operation conditions of Real-Time Monitoring frequency converter and each power cell; add the protection bypass that each power cell is equipped with, guaranteed its normal effectively operation, thus the high efficiency of realization, high power factor and high reliability.The present invention's two control method, has realized the concrete control mode of high-voltage variable-frequency and variable-speed system, each concrete steps steps such as () warning that especially has, fault detect, processing make high-voltage variable-frequency and variable-speed system efficiently, accurately, operation in an orderly manner.
Accompanying drawing explanation
Fig. 1 is the structural representation of one of the present invention's high-voltage variable-frequency and variable-speed system;
Fig. 2 is the main circuit diagram of power cell in one of the present invention's high-voltage variable-frequency and variable-speed system;
Fig. 3 is the flow chart of the present invention's two control method;
Fig. 4 is the flow chart of PWM interrupt process in the present invention's two control method.
Embodiment
Below in conjunction with accompanying drawing, the invention will be further described.
Refer to Fig. 1, a kind of high-voltage variable-frequency and variable-speed system of one of the present invention, is connected between three phase mains 100 and motor 300, and high-voltage variable-frequency and variable-speed system comprises phase shifting transformer 1, frequency converter 2, optical fiber interface 3 and control unit 4, wherein:
Phase shifting transformer 1 comprises former limit winding and 3n secondary winding, former limit winding connects three phase mains 100, each secondary winding all connects a power cell 21 according to extend-triangle connection, powers to power cell 21, thereby reaches the object that reduces Harmonics of Input;
Control unit 4 connects each power cell 21 by optical fiber interface 3, controls concurrently each power cell 21 with many level PWMs control mode, makes frequency converter 2 sine wave output electric currents, thereby realizes the high-quality control to motor 300; And the running status of control unit 4 real time monitoring frequency converters 2 and each power cell 21, gather the information (input current, output current and output voltage) of frequency converter 2 and the information (busbar voltage, output voltage and communication condition) of each power cell 21, and determine alarm condition and malfunction according to these information, report to the police or fault if existed, by manually getting rid of, the instruction of operation respective handling; In the present embodiment, control unit 4 is not shown in the figures by interconnective dsp chip (not shown) and FPGA() realization of chip formation, fpga chip connects each power cells 21 by optical fiber interface 3; It is TMS320F28335 that dsp chip is selected model.
In the present embodiment, high-voltage variable-frequency and variable-speed system also comprises the touch-screen 5 of a connection control unit 4, for realizing man-machine interaction, realizes the demonstration of the running status of frequency converter 2 and each power cell 21, and for manual control; Meanwhile, the present invention also can realize remote control by telecommunication agreement.
As shown in Figure 2, in the present embodiment, power cell 21 comprises:
Three-phase commutation bridge 211, is made up of six diode D1 to D6, is direct current for the interchange input rectifying that a secondary winding of phase shifting transformer 1 is provided;
In capacitance group 212(the present embodiment, be single electric capacity), for storing the direct current being obtained by three-phase commutation bridge 211 rectifications;
Refer to Fig. 3, the present invention's two the control method based on one of the present invention high-voltage variable-frequency and variable-speed system, comprises the following steps:
Step S1, initialization control unit 4, makes each parameter initialization of control unit 4;
Step S2, upgrades interrupt vector table;
Step S3, opens house dog;
Step S4, open PWM interrupt process, shown in interrupt vector table, control unit 4 gathers the information of a power cell 21 and the input/output information of frequency converter 2, analyze and process alarm condition and malfunction, in the time of alarm free, fault or eliminating, report to the police, after fault, calculate PWM duty ratio and send to the power cell 21 of current controlled unit Information Monitoring, then feed dog, repeating step S4 to house dog;
Refer to Fig. 4, the concrete steps of step S4 are as follows:
Step S401, whether detection alarm, failure reset flag bit be effective, as effectively, enters step S402; As invalid, enter step S403;
Step S402, warning, failure reset flag bit reset;
Step S403, according to interrupt vector table, determines the power cell 21 of current wanted Information Monitoring;
Step S404, busbar voltage, output voltage and the communication state of the determined power cell 21 of acquisition step S403, analyze alarm condition and the malfunction of this power cell 21;
Step S405, input current, output current and the output voltage of collection frequency converter 2, carry out digital filtering, obtains each digital signal, carries out electrical quantity safety protection control, in the time that each parameter exceeds threshold value, takes corresponding protection control, Accident prevention;
Step S406, the each digital signal obtaining in read step S405, alarm condition and the malfunction of analysis frequency converter 2;
Step S407, for alarm condition and the malfunction of power cell 21 in step S404, and alarm condition and the malfunction of frequency converter 2 in step S406, report to the police or fault if existed, move corresponding processing instruction (manual operation, eliminating, input), and enter step S408; If there is no report to the police or fault, enter step S409;
Step S408, whether the processing instruction that detects operation is effective, if effectively, enter step S409; If invalid, enter step S410;
Step S409, calculates the PWM duty ratio for controlling the determined power cell 21 of step S403 and is transferred to this power cell 21, realizes the control to it;
Step S410, house dog feeds dog, then enters step S401.
In sum, high-voltage variable-frequency and variable-speed system of the present invention can be realized the high-quality control to motor, significantly saves energy, and the control method providing can guarantee system high efficiency, safe operation in an orderly manner, thus the high efficiency of realization, high power factor and high reliability.
Above embodiment is used for illustrative purposes only, but not limitation of the present invention, person skilled in the relevant technique, without departing from the spirit and scope of the present invention, can also make various conversion or modification, therefore all technical schemes that are equal to also should belong to category of the present invention, should be limited by each claim.
Claims (7)
1. a high-voltage variable-frequency and variable-speed system, is connected between three phase mains and motor, it is characterized in that, this high-voltage variable-frequency and variable-speed system comprises phase shifting transformer, frequency converter, optical fiber interface and control unit, wherein:
Frequency converter, comprises 3n identical power cell, and n >=2 and n are integer; Every n power cell is followed in series to form a phase, the star-like rear described motor that connects that is connected of three-phase;
Phase shifting transformer, comprises former limit winding and 3n secondary winding, and former limit winding connects described three phase mains, and each secondary winding all connects a power cell according to extend-triangle connection;
Control unit, connects each power cell by described optical fiber interface, controls concurrently each power cell, and the running status of real time monitoring frequency converter and each power cell.
2. high-voltage variable-frequency and variable-speed system according to claim 1, is characterized in that, described control unit comprises interconnective dsp chip and fpga chip, and fpga chip connects each power cell by described optical fiber interface.
3. high-voltage variable-frequency and variable-speed system according to claim 1 and 2, is characterized in that, described power cell comprises a protection bypass, for this power unit by-pass when breaking down.
4. high-voltage variable-frequency and variable-speed system according to claim 3, is characterized in that, described high-voltage variable-frequency and variable-speed system also comprises the touch-screen of the described control unit of a connection, for realizing man-machine interaction.
5. high-voltage variable-frequency and variable-speed system according to claim 3, is characterized in that, described n is 6.
6. the control method based on high-voltage variable-frequency and variable-speed system described in claim 1, is characterized in that, comprises the following steps:
Step S1, control unit described in initialization;
Step S2, upgrades interrupt vector table;
Step S3, opens house dog;
Step S4, open PWM interrupt process, shown in interrupt vector table, described control unit gathers the information of a power cell and the input/output information of frequency converter, analyze and process alarm condition and malfunction, in the time of alarm free, fault or eliminating, report to the police, after fault, calculate PWM duty ratio and send to the power cell of current controlled unit Information Monitoring, then feed dog, repeating step S4 to house dog.
7. control method according to claim 6, is characterized in that, described step S4 comprises the following steps:
Step S401, whether detection alarm, failure reset flag bit be effective, as effectively, enters step S402; As invalid, enter step S403;
Step S402, warning, failure reset flag bit reset;
Step S403, according to interrupt vector table, determines the power cell of the Information Monitoring of wanting;
Step S404, busbar voltage, output voltage and the communication state of the determined power cell of acquisition step S403, analyze alarm condition and the malfunction of this power cell;
Step S405, input current, output current and the output voltage of collection frequency converter, carry out digital filtering, obtains each digital signal;
Step S406, the each digital signal obtaining in read step S405, alarm condition and the malfunction of analysis frequency converter;
Step S407, for alarm condition and the malfunction of frequency converter in the alarm condition of power cell in step S404 and malfunction and step S406, reports to the police or fault if existed, and moves corresponding processing instruction, and enters step S408; If there is no report to the police or fault, enter step S409;
Step S408, whether the processing instruction that detects operation is effective, if effectively, enter step S409; If invalid, enter step S410;
Step S409, calculates the PWM duty ratio for controlling the determined power cell of step S403 and is transferred to this power cell;
Step S410, house dog feeds dog, then enters step S401.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN105978357A (en) * | 2015-03-10 | 2016-09-28 | Ls产电株式会社 | Inverter system |
| CN106712648A (en) * | 2017-03-08 | 2017-05-24 | 南通大学 | Online fault rapid detection and bypass protecting method for high-voltage variable-frequency speed control system |
| CN106712647A (en) * | 2017-03-08 | 2017-05-24 | 南通大学 | High voltage variable frequency speed regulation system with on-line fault detection and bypass protection functions |
| CN107037359A (en) * | 2017-03-21 | 2017-08-11 | 上海新时达电气股份有限公司 | A kind of method of the use cascaded high-voltage frequency converter off-line identification parameter of electric machine |
| CN113839597A (en) * | 2021-09-08 | 2021-12-24 | 西安陕鼓动力股份有限公司 | Motor starting method, motor starting and synchronous operation method with different power supplies supplying power |
| WO2023221386A1 (en) * | 2022-05-18 | 2023-11-23 | 烟台杰瑞石油装备技术有限公司 | Variable-frequency drive system, frequency conversion and speed regulation all-in-one machine, pumping system and well site arrangement |
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| CN113839597A (en) * | 2021-09-08 | 2021-12-24 | 西安陕鼓动力股份有限公司 | Motor starting method, motor starting and synchronous operation method with different power supplies supplying power |
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| WO2023221386A1 (en) * | 2022-05-18 | 2023-11-23 | 烟台杰瑞石油装备技术有限公司 | Variable-frequency drive system, frequency conversion and speed regulation all-in-one machine, pumping system and well site arrangement |
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Application publication date: 20140514 |