CN2376371Y - Frequency converter for concrete vibrator - Google Patents

Abstract

The utility model relates to a frequency converter for a concrete vibrator. The utility model comprises a variable-voltage rectifying filter circuit which is connected with a power supply device, and a microcontroller which is connected with the vibrator, wherein, the microcontroller is composed of a single-chip machine with pulse-width modulation or an integrated circuit, and the microcontroller produces pulse width signals, time sequence signals and control signals; a driver is connected with the microcontroller and the filter circuit to finish the driving of the pulse-width modulation signals, to generate driving voltage; a switch power device is connected with the microcontroller and the output end of the driver to accept the driving voltage to generate three-phase sine alternating current to drive the vibrator. The utility model has the characteristics of machine maintenance elimination, no noise, small size, convenient movement, combination of electromechanical protection and electromechanical control, etc. The utility model has a variable-frequency multipurpose function and an auxiliary function.

Description

The concrete vibrator frequency converter

The utility model relates to power source special and the supporting control appliance of concrete with vibrator.

Concrete vibrator adopts two kinds of frequencies to be respectively 150 and 200HZ in the building trade, particularly hydraulic architecture construction, and the induction asynchtonous motor that voltage is 48V is the eccentric rotary insertion vibrator of power.Its supply unit is the generating set by the motor Driven by Coaxial, i.e. frequency converter, and every kind of product only provides a kind of frequency current of output, and the relay auxiliary equipment that is used for frequency converter protection and far distance controlled " startup ".Its shortcoming is: 1, adopt mechanical part, maintenance task is heavy, and 2, noise is big, 3, volume is big.

The utility model purpose provide a kind of do not have machinery part, noiselessness, volume little, be that PWM frequency conversion and control appliance are the concrete vibrator frequency converter of one.

The purpose of this utility model is achieved in that a kind of concrete vibrator frequency converter, comprises that the transformation, rectification, the filter circuit that link to each other with supply unit provide dc source, constitutes power circuit; The microcontroller that is connected with vibrator is characterized in that: microcontroller is made up of the single-chip microcomputer or the integrated circuit of the wide modulation of dai channel, produces pulsewidth, sequential, control signal; Driver is connected with microcontroller, and driver links to each other with power circuit, finishes pulse-width signal and drives, and produces driving voltage; The switch power device is connected with the drive circuit output, accepts the driving voltage that drive circuit produces, and producing the three-phase virtual value is that sinusoidal alternating current constitutes frequency converter, drives vibrator.The switch power device adopts IGBT template and MOSFET pipe.Microcontroller is that 80 * 96 series monolithics 8098 are as main frame.Four line connected modes of frequency converter and vibrator constitute the command signal testing circuit with microprocessor and interface circuit, finish to distinguish and handle, and obtain control instruction and " startup ", " stopping " and interfering signal.

Because the utility model is the inverter power supply that is made of the microcontroller of the wide modulator of dai channel (PWM) and switch power device, it is the PWM frequency converter, can supply with and realize concrete two kinds of three-phase alternating currents of 150/200HZ, its characteristics have: 1, do not have mechanical part, can exempt maintenance of machine; 2, noiselessness, volume is little, is easy to move; 3, set up variable ratio frequency changer multipurpose and miscellaneous function; 4, mechanical and electrical protection and be controlled in one is a kind of desirable vibrator special converter, can be widely used in building operations department.

Below in conjunction with drawings and Examples the utility model is further described.

Fig. 1 is a theory diagram of the present utility model.

Fig. 2 is the utility model detection signal schematic diagram.

Fig. 3 is circuit theory diagrams of the present utility model.

Fig. 4 is circuit theory diagrams of the present utility model.

Fig. 5-Fig. 7 is the flow chart of the utility model embodiment.

The driving stage that the inverter that pulsewidth modulation (PWM) and high-power switch device constitute is made asynchronous induction machine can realize the frequency control of three-phase alternating current.Its principle is that the pulsewidth of carrier frequency is with sinusoidal manner conversion three-phase SPWM frequency converter modulation pulsewidth:

△A＝T _R/2(1+MSina _i)

△B＝T _R/2(1+MSin(a _i+2/3π))

△C＝T _R/2(1+MSin(a _i+4/3π))

Wherein: T _R-carrier cycle

M-voltage modulated ratio

a _i-each carrier wave parallactic angle (i=1,2,3 ... R)

Carrier cycle T _RBe calculated as follows: $T_R=\frac{1}{\mathrm{Rf}}$ Wherein: the R-carrier wave ratio

F-frequency converter output frequency

The utility model comprises corresponding software by the single-chip microcomputer (microcontroller) of band PWM, signal deteching circuit, and compositions such as driving and holding circuit, structure is seen accompanying drawing 1.

System is with power frequency supply power supply as inverter after transformation, rectification, filtering obtain the 50V direct current.According to instruction and operating condition requirement, its main program and waveform generator provide SPWM pulsewidth, sequential and control signal by microcontroller 80 * 96 series monolithics, constitute the core.Three-phase six road pwm signals that produce remove to touch drive circuit by HSO high-speed output end mouth.According to existing concrete vibrator requirement, frequency converter only need be exported the three-phase alternating current of fixing two kinds of operating frequencies of 150 and 200HZ, but frequency transformation manual switchover main program parameter can be realized.Special purpose driver IC before the high-power switch device has overcurrent, overvoltage, error-logic control protection electric circuit; to guarantee that high-power switch device is operated in legal duty; suffering can be blocked the output of this driving stage when illegal state, inform microcontroller simultaneously.High-power switch device adopts IGBT template or MOSFET pipe, and its grid is that voltage drives, and antijamming capability is strong, drives fairly simple.

Control is to adopt four lines to be connected with vibrator to former frequency converter with relay, wherein a line is the control detection signal, when this line and other a three-way wherein line touch fashionable, to obtain the instruction of " startup " "signal for " stop ", for with the original equipment compatibility, detect control signal also according to this mode realize, adopt the detection signal circuit of Fig. 2, CPU started " startup " program for the treatment of when frequency converter was in " stopping " state, if program at first stops to treat " startup " program after obtaining " startup " signal, restart the PWM frequency converter.When detecting "signal for " stop ", program should check whether be " startup " duty, if promptly stop the PWM frequency converter, working procedure is established to disappear and arrogated to oneself process, avoids interference to cause maloperation.Work safely and reliably in order to make inverter; this inverter adopts defencive functions such as overcurrent, overvoltage; system's continuous monitoring; once occur submitting to unusually to interrupt; microprocessor stops PWM ripple output, simultaneously fault is stored in the internal memory with code form, so that come by the read failure code during trouble hunting; judge whether frequency converter breaks down rapidly, thereby make maintenance work convenient rapidly.

The hardware configuration of single-chip microcomputer and PWM frequency converter;

The control section structure principle chart is selected for use the strong MOS-80 of function * 96 series monolithics 8098 as system host, and is used the 8098 PWM functions that are as shown in Figure 3.Drive and see shown in Figure 4 with inverter circuit.

1, be not with the internal processes memory owing to 8098, therefore utilize 8KEPROM2764 to make memory under program and PWM tables of data memory, 2764 addresses are 2000H-3FFFH, and chip selection signal is from the IC of decoder 74LS139 ₅BY1.I/O expands with 8255, and 8255 are operated in mode " 0 ", and the Gao Siwei of PA and PC constitutes demonstration, the warning output, and display is by B ₁-B ₇, N ₁-N ₃Drive.P _cGao Siwei and low four formation key input section.Display adopts three LED dynamically to show, instruction is by S ₁-S ₆Key in, 8255 addresses are 4000H-4004H.

2, main circuit control, data acquisition and detection all adopt light every, OP ₁With 03 and the QIBH network constitute under-voltage detection, voltage signal carries out the A/D conversion by the input of 8089 ACH port.CAO network and O ₄Constitute over-current detection, driver IC ₁Amplifier in the sheet is through O ₄To ACH ₆Carry out the A/D conversion, the electric current of conversion, the voltage detecting data are handled by microprocessor.According to fault by IC ₁Sheet inner treater and R ₁₀-R ₁₂Constitute, the fault detect network, when limit fault by IC ₁Comparator provides negative logic, blocks driver and proposes interrupt requests simultaneously, by the response of CPU external interrupt (reporting to the police, write down, stop PWM output etc.) is handled in system lock.

3, PWM port, O ₂, SCR network and R ₁₄, S ₁Protection when constituting the startup of erosion control and frequency converter ends S by the CPU program when main circuit and frequency converter startup ₁Make R ₁₄Be serially connected with in the power supply in case the rush of current when starting, during operation by programmed instruction conducting S ₁, short circuit R ₁₄Make circuit be in the operation duty.The EKG switch is accepted frequency converter remote " startup " and "signal for " stop " under cpu instruction requires.

4, driver IC ₁, finish pwm signal and drive, provide the driving voltage of power devices at different levels by internal circuit, by power device according to pwm signal " unlatchings " and " end ", the three phase sine alternation electricity of formation SPWM, the vibrator of driving asynchronous machine formation.

The software configuration of system;

Scm software structure collectivity scheme: guarantee that the frequency converter device security starts reliably and moves, adopt " startups/operation " two cycle detection controls on the software, the detection of fault and protect the software continuous monitoring of employing to carry out; Utmost point barrier fault adopts interrupts processing mode; The PWM operation adopts the HSO interrupt mode to carry out; The dynamic circulation of demonstration and keyboard work; Program sees shown in the block diagram 1.

1, main program

Include two circulations in the main program, detect the main circuit state-detection before frequency converter work is finished in circulation before main circuit is opened, only when fault-free, allow " startup " indication L ₁Set.Can enter second circulation, the outside input instruction of inquiry " startups " " stops " " just/reverse " and frequency setting, starts every trace routine and display and dynamically shows by the display buffer content.After the main program initialization, the adhesive of instruction undercurrent relay makes main circuit and power connection, and continuous measuring voltage U, when U＜when 80% rectification output was unstable, instruction controllable silicon SOR-F ended circuit R ₁₄In the serial connection main circuit, the electric capacity charge circuit can be avoided heavy current impact, when stationary value is exported in U＞80% rectification, and instruction triggers SCR conducting short circuit resistance R ₁₄The startup stage of frequency converter, by software instruction by SCR, the excessive frequency converter operate as normal that influences of electric current when being used for the main circuit step-down and avoiding induction machine to start.

2, initialize routine

Remove setting and the 8255 working method initialization of finishing system parameter setting, interrupt vector in the initialize routine, simultaneously to log zero clearing and driver IC ₁Initial set makes power device avoid abnormal state when circuit is opened.

3, show the key assignments response, operation detects circulation

Demonstration and keyboard detection adopt 8255 dynamic operation processing modes; CPU need go on doing in processing; working state of system is as " startup "; " stop " allowing whether to start; frequency values; just/inverted status; display routine converts state to reveal codes in the equal writing system status register of malfunction; write the buffer area demonstration that circulates; and key assignments detected; after disappearing and arrogate to oneself, record judges whether the instruction establishment; and execution command adapted thereto program; testing process is respectively protected in the cyclic program startup under the no instruction situation; the permission A/D converter interrupts; this cycle period is controlled at less than 20ms; answer the check system state before the cycle detection; judge whether necessity, as in frequency converter " startup " stage.

4, " startup ", " stopping " handling procedure

In out of service, remote " starting/stop " control also uses HSO to interrupt providing sensed signal sources, and therefore startup and halt instruction promptly are according to system mode, and whether decision instruction sets up, and carries out corresponding processing program.Halted state HSO is conducting U regularly ₁-U ₃, U ₄-U ₆All the time be in cut-off state, the EKG termination is received enabled instruction.The EKG end is in equally and treats that " stopping " detecting under the running status, should whether judge at definite starting state during as the acquisition instruction.

5, the HSO of PWM operation interrupts handling

PWM is in operation pulsewidth should be by the sinusoidal manner conversion, its pwm value is stored among the EPROM by phase place with forms mode, at first detect the phase counter of written data last time during the response of HSO interrupt routine, judge the minimum value of phase place during each mutually, calculate according to this and should write the pulsewidth address its next time, look into lookup table mode and to get pwm value, its time value as calculated with trigger mutually number, after write in the lump in the HSO register " CAM ", treat HSO by oneself, the HSO interrupt priority level should be only second to " WCINT " external interrupt.

6, the interrupt routine of running protection detection and limit fault

Regularly start A/D converter in the main program circulation, the data after the conversion are handled with interrupt mode.A/D conversion startup should be controlled in the wideest pulse to avoid the influence of PWM to detecting.Detection data and last secondary data after the interrupt response compare, and check situation of change, situation of change is noted down wait to look into, and the delta data absolute value increases progressively continuously, and during the value of overstepping the extreme limit, system should quit work and report to the police, record under instruct.CPU only stops PWM output in the interrupt requests of limit fault, and it is for future reference to make log on request.

Claims (4)

1, a kind of concrete vibrator frequency converter comprises that the transformation, rectification, the filter circuit that link to each other with supply unit provide dc source, constitutes power circuit; The microcontroller that is connected with vibrator is characterized in that: microcontroller is made up of the single-chip microcomputer or the integrated circuit of the wide modulation of dai channel, produces pulsewidth, sequential, control signal; Driver is connected with microcontroller, and driver links to each other with power circuit, finishes pulse-width signal and drives, and produces driving voltage; The switch power device is connected with the drive circuit output, accepts the driving voltage that drive circuit produces, and producing the three-phase virtual value is that sinusoidal alternating current constitutes frequency converter, drives vibrator.

2, concrete vibrator frequency converter according to claim 1 is characterized in that the switch power device adopts IGBT template and MOSFET pipe.

3, concrete vibrator frequency converter according to claim 1 is characterized in that microcontroller is that 80 * 96 series monolithics 8098 are as main frame.

4, concrete vibrator frequency converter according to claim 1, the four line connected modes that it is characterized in that frequency converter and vibrator, constitute the command signal testing circuit with microprocessor and interface circuit, finish and distinguish and handle, obtain control instruction and " startup ", " stopping " and interfering signal.

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