CN201303308Y - Dynamic simulation device for prime mover system of electric generator - Google Patents
Dynamic simulation device for prime mover system of electric generator Download PDFInfo
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- CN201303308Y CN201303308Y CNU2008201592938U CN200820159293U CN201303308Y CN 201303308 Y CN201303308 Y CN 201303308Y CN U2008201592938 U CNU2008201592938 U CN U2008201592938U CN 200820159293 U CN200820159293 U CN 200820159293U CN 201303308 Y CN201303308 Y CN 201303308Y
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Abstract
The utility model discloses a dynamic simulation device for a prime mover system of an electric generator. The dynamic simulation device is characterized by the inclusion of a microprocessor, a detection circuit used for being connected with a sensor, an output circuit used for being connected with the electric generator and a display; and the detection circuit, the output circuit and the display are respectively connected with the microprocessor. The dynamic simulation device further comprises a communication circuit, and the communication circuit is connected with an upper computer in a communication manner. The device can intuitively display various data parameters and can be in communication with the upper computer.
Description
Technical field
The utility model belongs to electric and electronic technical field, relates to a kind of device of generator prime system dynamic simulation.
Background technology
The generator prime system simulation model is one of visual plant of Electrical Power System Dynamic simulation, be mainly used in the electric power system scientific research of scientific research institutions and Electric Power Automation Equipment manufacturing enterprise, research and development and the power product check and measurement of electric power new technology and equipment, and the scientific research of institution of higher learning and experimental teaching.
At present both at home and abroad the simulator that adopts mostly is full simulation control, has shortcomings such as complex structure, electronic devices and components are aging easily, easily influenced by ambient temperature, poor anti jamming capability and automaticity be low.Minority adopts D/A control, but fails to realize and PC communication function and functions such as remote sensing, remote measurement, remote control, definite employing conventional method of PI parameter, system debug with safeguard complexity.
Table 1: domestic and international Electrical Power System Dynamic simulated profile
Table 2: generator prime system emulation device the key technical indexes contrast both at home and abroad
*Refer to analogue system dynamic characteristic index and MATLAB Digital Simulation relative error as a result,
*KGS type silicon controlled rectifier operation instructions (rectifier factory, Shanghai)
The utility model content
Technical problem to be solved of the present utility model provides a kind of device of generator prime system dynamic simulation, and this device can intuitively show various data parameters and can communicate by letter with host computer.
For solving the problems of the technologies described above, the technical scheme that the utility model adopted is:
A kind of device of generator prime system dynamic simulation is characterized in that, the testing circuit that comprise microprocessor, is used for being connected with transducer, is used for the output circuit and the display that are connected with generator; Described testing circuit, output circuit and display all are connected with microprocessor.
This device also comprises telecommunication circuit, and this telecommunication circuit and host computer communicate to connect.
Described telecommunication circuit adopts the R485 telecommunication circuit.
Described output circuit is a rectifying output circuit; Described testing circuit is gathered armature supply, armature voltage, exciting current and rotary speed data; Described display adopts LCD display.
The beneficial effect that the utility model had has:
This device adopts LCD liquid crystal Chinese data to show in real time, makes the user can carry out operations such as parameter adjustment more intuitively.
This device has the R485 serial communication interface, can be used to be connected with PC or with control and monitor console, monitors use for the monitor staff.
Description of drawings
Fig. 1 device general principles block diagram;
Fig. 2 armature supply circuit;
Fig. 3 excitation power supply circuits;
Fig. 4 piezo-resistance protective circuit;
Fig. 5 open-phase protection circuit;
Fig. 6 operation circuit schematic diagram;
The digital control part theory diagram of Fig. 7.
Embodiment
The utility model is described in further detail below in conjunction with accompanying drawing.
Embodiment 1:
Utilization electric power system physical analogy and mathematical simulation basic theories and physical similarity fundamental theorem, set up generator prime system (speed regulator, pipe characteristic and prime mover self-equilibrium characteristic) common simulation (mathematics) model, break through the traditional thought of pure simulation hardware and full simulation control, employing is based on micro-processor controlled driving system dynamic emulation method, utilization simulation hardware and software emulation, simulation are controlled with digital control and method that mathematical simulation combines with physical analogy and are utilized the communication technology, have realized the emulation of generator prime system dynamic characteristic.
This device is simulated the true prime mover (hydraulic turbine and steam turbine) and the speed regulator thereof of electric power system, is made up of digital control part, simulation control part and major loop, as shown in Figure 1.Digital control part is finished the emulation of prime mover speed regulator, and it is the emulation of the hydraulic turbine and steam turbine self-equilibrium characteristic that simulation control part, major loop and DC motor are finished prime mover, and they finish the emulation of prime mover and governing system thereof jointly.
The major loop function: three-phase alternating-current supply is transformed to DC power supply through controlled rectifier, produces trigger impulse by control circuit and regulates direct voltage, to power to DC motor and to regulate generating unit speed.
Operation circuit function: each switch on the major loop is controlled, also carried out the mutual of signal simultaneously, finish functions such as signal alarm with control circuit.
Control circuit function:, suitable trigger impulse is provided for each thyristor of three-phase controlled rectification bridge of major loop by signal acquisition process to major loop.Can provide guard signal to operation circuit during fault, cut off the power supply of major loop by operation circuit.
4.2 major loop
Major loop provides armature piezoelectric voltage and exciting current for the 20KW direct current machine, and provides protection to main circuit.
4.2.1 armature voltage forms circuit
Adopt DC motor to simulate prime mover, need provide direct current as armature voltage, adjusting to motor speed is to realize by the size that changes armature voltage, the three-phase controllable silicon rectifier circuit of design changes the three-phase alternating-current supply in the electrical network into voltage swing adjustable DC power supply.Its circuit as shown in Figure 2.
KM1 is an A.C. contactor among the figure, as the mains switch of major loop; TM1 is three phase mains transformer (no-load voltage ratio is 380/200), and its capacity is according to different units and different.
VT1～VT6 is for constituting six thyristors of rectifier bridge, and six road trigger impulses that formed by control circuit can be controlled the conducting of respective thyristor respectively, with the size of change rectifier output voltage; TDV1, TDV2 are respectively current sensor and voltage sensor, and M1 and M2 will reflect that the analog signal of armature supply actual value and armature voltage actual value passes to control circuit and handles; LK is a smoothing reactor, makes the DC side electrorheological get continuously smooth.
4.2.2 exciting current forms circuit
DC motor is in perseverance and encourages state in native system, and promptly exciting current is constant, can realize with a uncontrollable rectifier bridge, selects suitable three-phase transformer just can obtain needed dc excitation power.As Fig. 3.
4.2.3 the protective circuit of major loop
(1.) overvoltage protection
The piezo-resistance model that this device is selected for use is TVR14681, and its rated voltage U1mA is 680V, residual voltage ratio UY/U1mA=1120V/50A, discharge capacity 4500A.
The connection of piezo-resistance as shown in Figure 4.
(2) overcurrent protection
F1 among Fig. 2, F2, F3 are fast acting fuse, can protect controllable silicon when electric current is excessive.The controllable silicon capability of overload is less, with controllable silicon the fast acting fuse of same amperage is arranged, and can burn out preceding fusing at controllable silicon, and the general fuse failure time is longer, can not play a protective role, so controllable silicon will be protected with fast acting fuse.If the silicon controlled rated current is bigger, and load current is less, and short-circuit current limiting device is arranged, then can adopt generally fuse protected.This device fast acting fuse parameter is 500V/300A.
(3) open phase protection
So-called open phase protection be meant the disappearance of electric current in the phase conductor that relies on three-phase circuit and disconnect protected equipment or rely on polyphase system one mutually or a few phase decompression prevent from power supply is applied to a kind of protected mode on the protected equipment.The native system open-phase protection circuit as shown in Figure 5.
N and DX1 are respectively primary side and the secondary side neutral point of major loop transformer TM1 among the figure.If A, B, C three-phase are just often, potential-free is poor between N and the DX1, rectifier bridge VD no-output electric current, and relay is failure to actuate; If phase failure situation occurs, then balance is broken between N and the DX1, and rectifier bridge makes the actuating of relay with output current, cuts off main circuit power by operation circuit then, has protected the safety of system and device.
4.3 operation circuit
Operation circuit is the circuit that carries out information interaction between user and the system, and the function that operation circuit need be realized has: to the combined floodgate and the separating brake of main circuit power; Provide start, shutdown, speedup, reduce-speed sign to control circuit; Report to the police when breaking down and the signal indication.Operation circuit is as shown in Figure 6:
(1). close a floodgate and sub-switching operation
The control of combined floodgate and separating brake realizes that by A.C. contactor KM1 contacting controling circuit as shown in Figure 6.
1QA is an automatic switch among the figure, provides operating power to operation circuit, and the selected device operation power supply of operation circuit should be the interchange of 220V as seen from the figure; D is the auxiliary contact of the closing relay in the control cabinet; SB2 is the local switch knob that is installed on the operation screen, and SB1 uses during as Long-distance Control; KM1 is an ac contactor coil, behind the coil electricity, and the main contact closure, its auxiliary contact KM1 self-locking keeps; HL1 is the start indicator light that is installed on the operation screen; K1 is the normally closed switch of separating brake relay.
The principle process of closing a floodgate is: press switch knob SB2, the 220V alternating voltage is connected at ac contactor coil KM1 two ends, its auxiliary contact KM1 action, indicator light HL1 is bright, switch closure above the major loop, realized the closing operation of major loop, the KM1 closure makes starting-up signal in the control system (STA) become effectively (low level) in the frame of broken lines simultaneously, thereby makes microsystem start operation.
As shown in Figure 6, need only one of D, SB1, SB2 closure and just can realize combined floodgate once, so have three kinds of modes can realize closing operation: (1) is passed through the top button realization combined floodgate (3) of operation screen by the realization combined floodgate of the software control relay in the control cabinet (2) and is realized combined floodgate by the button in a distant place.The separating brake control principle is similar with closing a floodgate, and it makes the KM1 tripping operation by the power supply that cuts off the closing operation loop, thereby has disconnected the power supply of major loop.B is a separating brake relay normally open auxiliary contact in the control cabinet among Fig. 6, by its folding of control system software control, SB3 is a distant place opening button, SB4 goes up switch knob for the operation screen, K4 is a normal opened contact of Fault Control relay, press the button SB4, the energising of relay K 1 two ends, its auxiliary contact all will move, and the K1 normally closed switch in the combined floodgate circuit makes the KM1 tripping operation with tripping, thereby cut off the power supply of major loop, simultaneously, the K1 closure in the separating brake part frame of broken lines makes the off signal (STO) of control system the inside become effectively (low level), and the microcomputer operation stops.
(2). speedup and deceleration-operation
The realization of speedup and deceleration is by providing pulse signal to reach to control system.On operation screen and control cabinet panel speedup and retard button have been installed all, every entering into DSP, and the suffered interference of the button signal on the control cabinet panel is little, directly enters DSP by light for the button signal on operation is shielded.
SB6 and SB7 are respectively the speedup and the retard button in a distant place among Fig. 6; SB5 and SB8 are respectively speedup and the retard button on the operation screen, are speedup and retard button on the control panel in the frame of broken lines.
3. protection shows with signal
The fault of system mainly contains open phase fault, overcurrent, overruns, loss of excitation is several, when fault takes place, by relevant protective circuit control relay action operation circuit is controlled.This part circuit mainly comprises: when breaking down, sub-switching operation is performed; Carry out fault alarm (emergency light, fault alarm bell); Can carry out fault after the fault resets.
J1 is the auxiliary contact of phase failure relay among Fig. 6, the protection relay contact that A is overcurrent, overrun, loss of excitation is shared, and they all are positioned at control cabinet; K4 is the Fault Control relay, and HL3 is a malfunction indicator lamp, and K5 is the fault recovery relay, and SB10 is a distant place fault recovery button, and SB9 is the fault recovery button on the operation screen, and BELL is the fault alarm bell.
When fault takes place; relay J 1 or A closure; thereby Fault Control relay K 4 is powered on; its all auxiliary contact actions, indicator light HL3 lights, and emergency alarm bell BELL reports to the police; the auxiliary contact closure of K4 on the sub-switching operation circuit; carry out sub-switching operation, cut off main circuit power, protected the safety of system.
After fault was eliminated, J1 and A were in off-state, and operation circuit can not automatically reset, and needed promptly to press SB9 by the reset button manual operation, made reset relay K5 action, and its normally closed switch is opened, thereby K4 returns to normal, and operation circuit is resetted.
4.4 digital control part
Prime mover simulation system, come down to a direct digital control system DDC (Direct Digital Contro1), with a single-chip microcomputer a plurality of procedure parameters (motor speed, terminal voltage Ud, armature supply Id and exciting current If) at controlled scene are gone the rounds to detect in the design, and result and set-point compared, carry out computing according to the control law in the Mathematical Modeling again, export corresponding results then, go to realize control, thereby finally finish closed-loop control motor speed to rectification module.System samples to exciting current, armature supply and the armature voltage of prime mover by AD; Simultaneously, be connected on the high speed input unit that rate signal that the Electromagnetically inductive speedometer on the motor main shaft produces has then directly entered CPU; System has obtained after the above-mentioned signal, according to the operational factor that the user sets, carries out the computing of a system complex, and last gained outputs to the silicon controlled rectifier module with digital control amount by the DA conversion; The button of system, switching value reach as the relay interface of protection and then expand by a slice 8255A; The user has designed a LCD MODULE and a serial communication interface in the system for convenience; Program running supervision and prime mover operational factor power-down protection have then passed through a slice X25043 to be realized.
4.4.1CPU and memory
16 single-chip microcomputer 80C196KC of a new generation that the digital control part of this analogue system is produced with Intel Company are as the control core, and crystal oscillator frequency is 12M, and the corresponding instruction cycle is 1.33us.80C196KC can be to 512 byte register direct controls in the CPU, very high service speed has been arranged data throughput capabilities.In addition, 80C196KC has the peripheral hardware task server, effectively the handling interrupt affairs.Peripheral hardware task server PTS (Peripheral TransactionServe) is to interrupting providing the response of a kind of similar direct memory visit DMA (Direct Memory Access), the expense of CPU than general interrupt response lack many.
Because the 80C196KC single-chip microcomputer does not have ROM in the sheet, the memory cell that itself provides is very limited, and control system need be handled lot of data, and program also will take memory space simultaneously, therefore, need expand memory.System has adopted the data storage of a slice 6264 (8K) as system; Because very big (Chinese character of Chinese character of using in the liquid crystal display program and the shared storage space of the type matrix of English character
[12]Be 32 * 32,128 bytes, and numeral or English are 16 * 32,64 bytes), so system has adopted a slice 27512 (64K) to make program storage, but because program needs and address assignment, real system has only been used the address space (2000H～9FFFH) of this program storage 32K.
4.4.2 analog signal channel
Having three tunnel analog signals (armature voltage Ud, armature supply Id, exciting current If) in the analogue system needs to detect, to be used for real-time control, protection and supervision.In order to make the shared a slice AD of three tunnel analog signals, increased a variable connector CD4051.CD4051 is one eight and selects one data selector, and its control pin A, B have been connected on HSO.0, the HSO.1 end of CPU respectively, and the C pin is ground connection then; Three tunnel analog signals then have been tapped at CH0, CH1 and CH2, rest channels ground connection; Like this, can select the signal gating that needs is sent into the A/D conversion chip by the control of CPU.8 or 10 figure place weighted-voltage D/A converters of 4 passages are arranged in the 80C196KC sheet, can directly adopt A/D in the sheet for general design.But the A/D input voltage is 0～5 volt in the sheet, and the highlyest has only 10, and in order to improve the operational precision of system, system has adopted a slice 12 A/D conversion chip AD1674 at a high speed, the connection that has adopted one pole+10V to import.Inner sampling holder (SHA) is arranged in the AD1674 sheet, need not external sampling holder again, be 10us its change-over time only, and include tristate buffer and latch, and sampling is accurately quick, thereby can simplify circuit design and improve system reliability.
Computer is handled each input data, obtains the power output Pm (K) of prime mover at last, removes to control the output voltage of SCR rectification circuit.This device has selected for use the D/A converter AD7245 of 12 of a slices to realize that power output Pm (K) is by the conversion of digital quantity to analog quantity.In order to guarantee the stable of output voltage, after AD7245, before the SCR rectification circuit, having adopted a slice OP07 that D/A is exported follows with anti-phase, strengthen its driving force, and with 0～5V voltage transition of D/A conversion output be corresponding SCR rectification circuit needed 0～-the 5V input voltage.
4.4.3 tachometric survey in real time
For real-time and the accuracy that guarantees motor speed is measured, system is the speed feedback of the Electromagnetically inductive speedometer acquisition motor of 180 pulse/commentaries on classics by a resolution, the motor revolution is crossed a circle, be connected on Electromagnetically inductive speedometer on prime mover main shaft and just can produce the square-wave signal of 180 amplitudes for+15V, signal is isolated through optocoupler and digital system, through being input to the high speed loader HSI of CPU after the Schmidt trigger shaping, high speed loader HSI is used to write down the time that a certain external event takes place again.By CPU high speed input unit HSI is programmed, respectively moment of adjacent twice pulse generation is read out and subtract each other, just can easily know the cycle of rate signal this moment, can obtain the real-time speed of prime mover again by a series of mathematical operation
4.4.4 the expansion of parallel port
When microsystem enlarges, often need expand I/O, used a 8255A parallel interface chip that the I/O of system is expanded.8255A has PA, PB and three programmable 8 I/O interfaces of PC, is the DIP40 encapsulation.Used the PA mouth to realize the input of button and switching value, the PB mouth then has been used as the output of relay protection signal, and the PC mouth then can be when being necessary resets to other peripheral hardware of system.8255A has three kinds of fundamental modes: mode 0, basic I/O mode; Mode 1, gating I/O mode; Mode 2, the bi-directional data load mode.According to system requirements, the working method of 8255A is set to 0, the input of PA mouth, and PB, the output of PC mouth, the connotation of the control word of contrast 8255A, its control word is 10010001B, i.e. 91H.
4.4.5 watchdog circuit and data cut-off protection
In order to guarantee operate as normal in system, just must monitor the operation of CPU, avoid deadlock, program fleet or enter endless loop.For this reason, select the house dog of X25043 for use, can send reset signal when out of control, make system break away from malfunction in system as system.What X25043 adopted is the SPI interface, because 80C196KC does not have the SPI interface, so use the P1 mouth of CPU to simulate the SPI interface house dog is programmed.In addition, X25043 includes the EEPROM of 512 bytes, and the data that can satisfy 10,000 times are erasable, the data retention period at least ten years.So, used as the preservation of each parameter after system's power down, make the motor operational factor after adjusting, just can remember automatically and preserve and need not each start and all will repeat to adjust.
4.4.6R485 serial communication interface and LCD
Native system has also designed a R485 serial communication interface, be used for being connected with PC or with monitoring, system accepts the various command of host computer by serial port, perhaps with information uploadings such as the various running statuses of control system, operational factors to PC, monitor use for the operations staff.
In addition, in order to give good man computer interface of user, user-friendly, it is 320 * 240 LCD that system has also adopted a resolution, link by 8 position datawires and 80KC196C single-chip microcomputer, the character of its demonstration adopts big font (Chinese character is 32 * 32, and English is 16 * 32), makes the user carry out the adjustment of prime mover operational factor more intuitively and obtains service data.
The beneficial effect that this device has:
(1) takes the magnetic induction speed probe, improved tachometric survey precision and Systems balanth.
(2) newly-increased power supply phase failure protection function, it is flexible that all protection working values can pass through panel button (update routine) No malfunction, tripping are set.
(3) have the in real time demonstration of LCD liquid crystal Chinese data, computer long distance communication and fault acousto-optic automatic alarm Function.
Claims (4)
1. the device of a generator prime system dynamic simulation is characterized in that, the testing circuit that comprise microprocessor, is used for being connected with transducer, is used for the output circuit and the display that are connected with generator; Described testing circuit, output circuit and display all are connected with microprocessor.
2. the device of generator prime system dynamic simulation according to claim 1 is characterized in that, also comprises telecommunication circuit, and this telecommunication circuit and host computer communicate to connect.
3. the device of generator prime system dynamic simulation according to claim 2 is characterized in that, described telecommunication circuit adopts the R485 telecommunication circuit.
4. according to the device of each described generator prime system dynamic simulation of claim 1～3, it is characterized in that described output circuit is a rectifying output circuit; Described testing circuit is gathered armature supply, armature voltage, exciting current and rotary speed data; Described display adopts LCD display.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201592938U CN201303308Y (en) | 2008-11-19 | 2008-11-19 | Dynamic simulation device for prime mover system of electric generator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2008201592938U CN201303308Y (en) | 2008-11-19 | 2008-11-19 | Dynamic simulation device for prime mover system of electric generator |
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| Publication Number | Publication Date |
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| CN201303308Y true CN201303308Y (en) | 2009-09-02 |
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| Application Number | Title | Priority Date | Filing Date |
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| CNU2008201592938U Expired - Fee Related CN201303308Y (en) | 2008-11-19 | 2008-11-19 | Dynamic simulation device for prime mover system of electric generator |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102184272A (en) * | 2011-01-28 | 2011-09-14 | 金华职业技术学院 | Virtual measuring and controlling system |
| CN106772042A (en) * | 2016-12-23 | 2017-05-31 | 清华大学 | A kind of generator prime system damping online test method |
-
2008
- 2008-11-19 CN CNU2008201592938U patent/CN201303308Y/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102184272A (en) * | 2011-01-28 | 2011-09-14 | 金华职业技术学院 | Virtual measuring and controlling system |
| CN102184272B (en) * | 2011-01-28 | 2012-11-14 | 金华职业技术学院 | Virtual measuring and controlling system |
| CN106772042A (en) * | 2016-12-23 | 2017-05-31 | 清华大学 | A kind of generator prime system damping online test method |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090902 Termination date: 20101119 |