CN102542888A - Comprehensive electrotechnical and electronic technique experiment platform - Google Patents

Abstract

The invention discloses an electrical and electronic technology comprehensive experiment platform, which is used to solve the technical problem that the existing electrical technology experiment equipment or electronic technology experiment equipment has single function. The technical solution is to integrate the power module, motherboard, error-checking function module, sub-board and virtual oscilloscope into one platform, design each experimental content of the electrical and electronic technology to be completed as a separate sub-board, and separate the experimental sub-boards to be completed It is directly plugged on the motherboard of the platform, and the experiment is carried out through the selection switch and the power supply required for the experiment. The experimental results are connected to the external computer through the data acquisition and processing unit, the virtual instrument unit, and the experimental result data or waveform is directly obtained; the comprehensive The experimental platform not only provides various basic, self-designed and comprehensive innovative experimental contents for electrical and electronic technologies, but also provides students, teachers and engineering technicians with a scientific instrument experiment platform for secondary development and technological innovation.

Description

Comprehensive experimental platform for electrical and electronic technology

technical field

The invention relates to an experiment platform, in particular to an electrical and electronic technology comprehensive experiment platform.

Background technique

Most of the existing experimental equipment are isolated equipment for electrical technology or electronic technology, and there are also a small number of experimental equipment for electrical technology or electronic technology synthesis, but these experimental equipment can only complete part of the relevant experimental content, such as Electrotechnical equipment can only complete simple DC circuit and AC circuit experiments, such as superposition principle, transient process analysis, single-phase series impedance test and other confirmatory experiments. Another example is that the electronic technology experimental equipment divides the analog electronic technology experiment and the digital electronic technology experiment into two types of equipment, and the amplifying circuit and integrated operational amplifier in the analog electronic technology experimental equipment use different experimental equipment; various experiments of digital electronic technology Devices can only conduct experiments with relatively independent content. Since the electrical technology and electronic technology experiments use different power supplies, the measuring instruments required for each experiment are also very different. In addition, the electrical and electronic components and circuit forms used in the existing experimental equipment are all fixed, and the experimenter can only complete the predetermined experimental content in a fixed mode.

Most of the electrical and electronic experimental devices commonly used are one experimental board for each experiment. The experimental technicians have to replace an experimental board before and after each experiment, and even need to build some circuits in advance. This not only increases the workload of the laboratory, but also does not It is beneficial to exercise students' hands-on ability. Discrete components and discrete instruments, this method is conducive to training students' experimental ability, but it brings difficulties to equipment management, and it is easy to cause damage and loss of equipment. In terms of instruments, only some of the functions of the existing instruments in the laboratory are used in teaching, and many functions are not available; on the other hand, some required functions are not available, and new equipment needs to be purchased. In addition, the update of the experimental content requires the purchase of new experimental equipment, which also causes some instruments to be idle and financially burdened.

Contents of the invention

In order to overcome the single-function deficiency of the existing electrotechnical technology experimental equipment or electronic technology experimental equipment, the present invention provides a comprehensive experiment platform for electrotechnical and electronic technology. The device includes a power supply module, a motherboard, an error checking function module, a daughter board and a virtual oscilloscope. The comprehensive experimental platform integrates the power module, motherboard, error checking function module, sub-board and virtual oscilloscope on the same platform, and designs each experimental content of the electrical and electronic technology to be completed as a separate sub-board, and each experimental sub-board to be completed They are directly plugged into the motherboard of the platform, and the experiment is carried out through the selection switch and the power supply required for the experiment. The experimental results are connected to the external computer through the data acquisition and processing unit, the virtual instrument unit, and the experimental result data or waveform can be directly obtained; The comprehensive experimental platform can not only complete various basic, self-designed and comprehensive innovative experimental contents of electrical technology and electronic technology, but also provide students, teachers and engineering technicians with a scientific instrument experiment platform for secondary development and technological innovation.

The technical solution adopted by the present invention to solve the technical problem is: a comprehensive experiment platform for electrical and electronic technology, which is characterized in that it includes a power supply module, a motherboard, an error checking control module, a daughter board, a data acquisition card and a PC. The power supply module, error checking control module, sub-board and data acquisition card are connected to the motherboard by standard connectors, and the data acquisition card communicates with the PC. The power supply module provides voltages of ±5V, ±12V, and 0-12V for the system. The motherboard is arranged with power interfaces 7, low-power speakers and drive circuits 8, high-power device interfaces 9, and seven segments from left to right and from top to bottom. Digital display 10, 50-pin connector 4, circuit voltage comparison and buzzer 5, LED driven by inverting gate 3, multi-frequency adjustable clock signal source 2, relay 11, potentiometer 12, eight-way logic switch output circuit 1 And the four-way pulse circuit 22, the air hole 6 is arranged in the middle of the motherboard, and the upper and lower sides of the air hole 6 are symmetrically distributed with pin headers 21. The power supply module leads the terminal to the power interface 7 on the motherboard, and the ±5V and ±12V ports of the power interface 7 on the motherboard supply power to the daughter board.

The error checking control module includes two parts: function selection input and function realization. The function selection input part provides the user with a function selection panel, and the function realization part uses the corresponding relay to open or close the experimental circuit. There are sixteen selection functions from 0 to F. Except for function 0, each function corresponds to a relay. The number of relays is designed to be fifteen, and a 4-16 decoder is used.

The data acquisition card and PC form a virtual oscilloscope, which uses standard serial and parallel ports for data acquisition, control and communication, and the 8051 single-chip microcomputer realizes the automatic switching range function.

The eight-way logic switching value output circuit 1 changes the high and low level output of the circuit board through the toggle switch. Multi-frequency adjustable clock signal source 2 generates clock signal, LED 3 driven by inverting gate builds inverting integrated circuit, fifty-pin connector 4 is used to connect motherboard and function selection module 20, circuit voltage comparison and buzzer 5 Provide the reference voltage for the motherboard, when the input voltage is higher than the reference voltage, the buzzer will alarm. Low-power loudspeaker and driving circuit 8 are made up of independent power amplifier and loudspeaker, and both are connected with wire. The seven-segment digital display 10 adopts common cathode connection. The four-way pulse circuit 22 generates input signal pulses, including rising edge pulses and falling edge pulses.

The motherboard is fixed on the box base 13 by bolts. The adjustable DC power supply 18, the power switch 19 and the function selection module 20 are fixed on the control panel 14 by bolts. The function selection module 20 is installed on the control panel 14, and the output of the function selection module 20 is connected to the motherboard.

The bottom of the box base 13 has a ventilation groove 15, and the inside of the box base 13 is distributed with a power conditioning circuit board 16, a toroidal transformer 17 and a DC adjustable power supply 18. The power conditioning circuit board 16 is on the left, and the toroidal transformer 17 is on the right. connected by wires. The toroidal transformer 17 is connected with the DC adjustable power supply 18 with a power line.

The daughter board includes an electronic technology module, a circuit chip module, an operational amplifier module, a DC/AC circuit module, a triode application circuit module, a thyristor application circuit module and a single-chip microcomputer simulation circuit module.

The multi-frequency adjustable clock signal source 2 adopts an integrated circuit 74HC14.

The LED 3 driven by the inverting gate adopts the integrated circuit 74LS04.

The power amplifier is a low voltage audio power amplifier LM386.

The high-power device interface 9 adopts ULN280× series chips.

The seven-segment digital display 10 adopts the chip MC14495.

The four-way pulse circuit 22 adopts a Schmitt trigger 74HC14 (1) chip.

The beneficial effects of the present invention are: because the present invention integrates the power supply module, motherboard, error-checking function module, sub-board and virtual oscilloscope on the same platform, each experimental content of the electrical and electronic technology to be completed is designed as a separate sub-board. The completed experimental sub-boards are directly plugged into the motherboard of the platform, and the experiment is carried out through the selection switch and the power supply required for the experiment. The experimental results are connected to the external computer through the data acquisition and processing unit, and the virtual instrument unit is directly obtained. Result data or waveforms; this comprehensive experimental platform not only provides various basic, self-designed and comprehensive innovative experimental contents for electrical and electronic technologies, but also provides secondary development, scientific and technological innovation for students, teachers and engineering technicians. scientific instrument experiment platform.

The present invention will be described in detail below in combination with specific embodiments.

Description of drawings

Fig. 1 is a schematic diagram of the structure of the electrical and electronic technology comprehensive experiment platform of the present invention.

Fig. 2 is a schematic diagram of the overall functional relationship of the electrical and electronic technology comprehensive experiment platform of the present invention.

Fig. 3 is a block diagram of the data acquisition card in Fig. 1 .

FIG. 4 is a schematic plan view of the motherboard in FIG. 1 .

Fig. 5 is an external structure diagram of the experiment box of the comprehensive experiment platform of electrical engineering and electronic technology of the present invention.

Fig. 6 is a schematic plan view of the control panel of the electrical and electronic technology comprehensive experiment platform of the present invention.

Fig. 7 is a diagram of the internal structure of the experiment box of the comprehensive experiment platform of electrical engineering and electronic technology of the present invention.

In the figure, 1- eight-way logic switch output; 2- multi-frequency adjustable clock signal source; 3- LED driven by inverting gate; 4- fifty-pin connector; 5- circuit voltage comparison and buzzer; 6- Air vent; 7-power interface; 8-low-power speaker and drive circuit; 9-high-power device interface; 10-seven-segment digital display; 11-relay; 12-potentiometer; 13-box base; 14-control panel 15-ventilation slot; 16-power conditioning circuit board; 17-ring transformer; 18-DC adjustable power supply; 19-power switch; 20-function selection module;

Detailed ways

Referring to Figures 1-7, the electrical and electronic technology comprehensive experiment platform of the present invention includes a power supply module, a motherboard, an error checking control module, a daughter board, a data acquisition card and a PC.

As an independent module of the system, the power module is physically represented as a PCB board, and the interface with the platform adopts a standard connector. The power input of the experimental system is 220V, 50Hz AC, and the power module provides voltages of ±5V, ±12V, and 0-12V for the system after step-down, rectification, filtering, and voltage stabilization. According to the design of the general power supply, this part will use the conventional method to design the circuit by first regulating the voltage of the transformer, then filtering and rectifying, and then sending it to the three-terminal voltage stabilizer to output the DC voltage. The fixed three-terminal voltage stabilizer is selected as the core device for design. 0 ~ 12V adjustable DC (VDC) adopts the design scheme of series feedback regulator circuit.

The mother board is arranged from left to right and from top to bottom with power interface 7, low-power speaker and drive circuit 8, high-power device interface 9, seven-segment digital display 10, fifty-pin connector 4, circuit voltage comparison and buzzer Device 5, LED driven by inverting gate, multi-frequency adjustable clock signal source, relay 11, potentiometer 12, eight-way logic switch output circuit 1 and four-way pulse circuit, vent hole 6 is set in the middle of the motherboard, and the vent hole 6 A row of pins 21 are distributed up and down. The motherboard connects all other modules and is the core of the structure. The motherboard PCB is composed of multiple functional areas, and it is also the support platform for each experimental sub-board, that is, the sub-board is connected to the motherboard through a connector. Motherboard function is a common element of multiple experiments, which is extracted and placed on the motherboard. The interface is a common connector. During the experiment, the motherboard is connected to the daughter board circuit through the connector to provide input and output interfaces. Each experiment also has a separate circuit board, which is plugged into the motherboard through a connector connection.

The error checking control module includes two parts: function selection input and function realization (that is, the action of the relay). Its function is to enable the experimenter to find out the problem in time when the experimental result does not match the expected result, mainly relying on the opening and closing of the relay to realize the circuit on and off. The function input part provides a function selection panel for the user, and the function selected by the user is output as a corresponding signal. There are two input methods: manual input and computer input. The function of the function realization part is to activate the corresponding relay according to different input signals, so as to open or close the experimental circuit. There are 16 selection functions from 0 to F. Except for function 0, each function corresponds to a relay, that is, when a function is selected, a relay will act. Therefore, the number of relays is designed to be 15, and a 4-16 decoder can meet the requirements.

The daughter board includes an electronic technology module, a circuit chip module, an operational amplifier module, a DC/AC circuit module, a triode application circuit module, a thyristor application circuit module, and a single-chip computer simulation circuit module. The design of the sub-board is to leave more space for users to play freely and avoid the constraints of verification experiments, so the above-mentioned modules can be designed individually or by students according to the needs of users.

The virtual oscilloscope is composed of a data acquisition card and a PC data processing program. Use the standard serial and parallel port of the microcomputer for data acquisition, control and communication, and use the enhanced parallel port (EPP) for data acquisition. In order to measure the signal beyond the A/D input range and improve the accuracy of measuring small signals, it is controlled by 8051 single-chip microcomputer to realize automatic control. Function to switch the range. The software part includes the 8051 program and the waveform display program running on the PC. The single-chip microcomputer program realizes the functions of receiving commands such as PC startup and setting sampling rate, range conversion, starting A/D, reading conversion results in response to A/D interrupts, and writing results to the EPP port of the PC. The PC program reads the measurement result data sent by the 8051 from the EPP, and after necessary processing, it is displayed graphically. 8051 uses a piece of 8255A programmable parallel I/O interface to realize the interface circuit with PC parallel port.

The power supply module provides voltages of ±5V, ±12V, and 0-12V, which are connected to the experimental platform through connecting wires. According to the purpose of the experiment, the operator builds the experimental circuit on the experimental platform and prepares for the experiment. The operator designs a given function input, and the error-checking control module decides whether the relay operates and transmits the result to the motherboard. After the experiment starts, the ±5V and ±12V ports on the motherboard supply power to the daughter board, receive the relay action signal at the same time, and send corresponding signals to the daughter board. After the experiment is completed, the display module or virtual instrument on the template transmits the experimental results to the operator. This completes a functional process, and if the operator needs to continue the experiment, the above actions are repeated.

The data acquisition card adopts an external type, and the data acquisition card collects the voltage data, and then communicates with the PC, and the data processing program on the PC processes and displays the waveform. The commonly used A/D converter input voltage generally does not exceed the range of plus or minus 20 volts, and the bipolar input voltage is even smaller. However, the voltage parameters to be measured on the platform will exceed the input range allowed by the A/D, so the data acquisition card has a voltage dividing function. When the measured voltage is relatively small, the A/D conversion accuracy is not high enough, and the signal needs to be amplified, so it is necessary to add a programmable amplifying circuit. After sampling and holding and A/D conversion, the data can be sent to the PC interface, and these processes are controlled by the 8051 single-chip microcomputer program. The PC program reads the data and processes the display.

In the eight-way logic switch output 1, the direct toggle switch can change the high and low level output of the circuit board. When the middle pin of the switch is connected to 0 volts, the logic output is 0 (low); when the middle pin of the switch is connected to 5V, the logic output is 1 (high). Each level output terminal is connected with a load resistor, and its function is to limit the current. The purpose of the multi-frequency adjustable clock signal source 2 is to generate clock signals in the frequency ranges of 60-600 Hz and 0.5-5 Hz. The ranges are realized by toggle switches. These clock signals can be used in sequential circuits. In this embodiment, an integrated circuit 74HC14, +5V power supply is used to generate clock pulses. In the LED 3 driven by the inverting gate, 74LS04 is selected to build the inverting integrated circuit, and a light-emitting diode is designed at the output end to display the level of the output end. When no signal is input, the state of the light-emitting diode is off. The function of the fifty-pin connector 4 is to connect the motherboard and the function selection module 20, select a double row single in-line plug to connect, and install four metal supports at the two ends of the plug to ensure stress. Circuit voltage comparison and buzzer 5 provides reference voltage for the mother board, when the input voltage is higher than the reference voltage, the buzzer will alarm. In this embodiment, a dedicated voltage comparison chip is selected, a pull-up resistor is connected to the output terminal of the comparison circuit, and a buzzer is connected to the output terminal. The function of the vent hole 6 is to assist heat dissipation. The power interface 7 provides a power interface for the circuit. It only needs to lead the terminal from the power module to the motherboard, including four types of +5V, -5V, +12V and -12V. The low-power loudspeaker and drive circuit 8 are composed of independent power amplifiers and loudspeakers, which can be connected with wires. The power amplifier is a low-voltage audio power amplifier LM386. The high-power device interface 9 adopts ULN280× series chips, and the function of eight light-emitting diodes is to display the potential level of the output terminal. A current-limiting resistor connected in series at the output terminal of the chip can prevent the diode from burning out due to excessive current. The chip MC14495 is selected in the seven-segment digital display 10, and the common cathode connection is adopted. The relay 11 provides two controllable relays for the circuit, and the Darlington tube is selected in the driving circuit. When the input is low level, the Darlington tube is not conducted, and the relay does not work; when the input is high level, the The Linton tube is turned on and the relay works. Potentiometer 12 is composed of three simple potentiometers, its function is to provide variable resistance or potentiometer for the experimental circuit, and each potentiometer provides three contacts. The pin header 21 is a single-row in-line type, which is symmetrically installed at the center of the motherboard. The function of the four-way pulse circuit 22 is to generate input signal pulses, including rising edge pulses and falling edge pulses. The switch is realized by a key switch, and the Schmitt trigger 74HC14 (1) chip is selected. When the switch is pressed, both rising and falling pulses will be generated simultaneously.

The box base 13 is used to support the mother board, and the mother board is fixed by bolt connection. The control panel 14 is used to support and fix the function selection switch 20 , the adjustable DC power supply 18 and the power switch 19 . The function selection module 20 is fixed on the control panel 14 by bolts. The function selection module 20 is installed on the control panel 14 and must be connected with the power circuit board and the function input circuit board. In addition, the output of the function selection module 20 is connected to the motherboard to control the opening and closing of the circuit.

Ventilation groove 15 is positioned at the bottom of casing, and its effect is to dissipate heat. The power conditioning circuit board 16 is on the left, and the toroidal transformer 17 is on the right, and the two are connected by wires. The power part needs to be grounded, and the power conditioning circuit board 16 and the toroidal transformer 17 are fixed on the box base 13 with screws. The toroidal transformer 17 and the DC adjustable power supply 18 are connected with a power line.

In this embodiment, the box body and the control panel are all made of 5mm steel plates, and the connection mode between the metal plates is bolted connection. Four identical rubber washers are installed on the box body base, and the installation position is 20mm from each edge line of the base.

Claims (8)

1. a kind of electrician and electronic technology comprehensive experiment platform, it is characterized in that: comprise power supply module, mother board, error-checking control module, sub-board, data acquisition card and PC; Power supply module, error-checking control module, sub-board and data The acquisition card and the motherboard are connected by standard connectors, and the data acquisition card communicates with the PC; the power supply module provides voltages of ±5V, ±12V, and 0-12V for the system, and the motherboard is arranged from left to right and from top to bottom. Power interface (7), low-power speaker and drive circuit (8), high-power device interface (9), seven-segment digital display (10), fifty-pin connector (4), circuit voltage comparison and buzzer (5 ), an LED driven by an inverting gate (3), a multi-frequency adjustable clock signal source (2), a relay (11), a potentiometer (12), an eight-way logic switch output circuit (1) and a four-way pulse circuit (22 ), a ventilation hole (6) is arranged in the middle of the motherboard, and the pin headers (21) of the ventilation hole (6) are symmetrically distributed up and down; )’s ±5V and ±12V ports supply power to the sub-board; the error checking control module includes two parts: function selection input and function realization; the function selection input part provides the user with a function selection panel, and the function realization part uses the corresponding relay to disconnect the experimental circuit or closed; there are 16 optional functions from 0 to F, except for function 0, each function corresponds to a relay, the number of relays is designed to be 15, and a 4-16 decoder is used; the data acquisition card is composed of a PC Virtual oscilloscope, using standard serial and parallel ports for data acquisition, control and communication, automatic range switching function is realized by 8051 single-chip microcomputer; eight-way logic switch output circuit (1) changes the high and low level output of the circuit board through the toggle switch; multi-frequency adjustable The clock signal source (2) generates a clock signal, the LED (3) driven by the inverting gate builds an inverting integrated circuit, the fifty-pin connector (4) is used to connect the motherboard and the function selection module (20), the circuit voltage comparison and The buzzer (5) provides the reference voltage for the motherboard, and when the input voltage is higher than the reference voltage, the buzzer will alarm; the low-power speaker and the drive circuit (8) are composed of an independent power amplifier and speaker, and the two are connected by wires The seven-segment digital display (10) adopts a common cathode connection; the four-way pulse circuit (22) generates input signal pulses, including rising edge pulses and falling edge pulses; the motherboard is fixed on the box base (13) by bolts; The DC power supply (18), the power switch (19) and the function selection module (20) are fixed on the control panel (14) by bolts; the function selection module (20) is installed on the control panel (14), and the function selection module (20 ) is connected to the motherboard; there is a ventilation slot (15) at the bottom of the box base (13), and the internal distribution power conditioning circuit board (16), toroidal transformer (17) and DC adjustable The power supply (18), the power supply conditioning circuit board (16) is on the left, and the toroidal transformer (17) is on the right, connected by wires between the two; the toroidal transformer (17) and the DC adjustable power supply (18) are connected with a power cord. 2. The electrical and electronic technology comprehensive experiment platform according to claim 1, characterized in that: the sub-board includes an electronic technology module, a circuit chip module, an operational amplifier module, a DC/AC circuit module, a triode application circuit module, a thyristor Application circuit module and single chip simulation circuit module. 3. The comprehensive experiment platform of electrical and electronic technology according to claim 1, characterized in that: the multi-frequency adjustable clock signal source (2) adopts an integrated circuit 74HC14. 4. The comprehensive experiment platform of electrical and electronic technology according to claim 1, characterized in that: the LED (3) driven by the inverting gate adopts an integrated circuit 74LS04. 5. The electrical and electronic technology comprehensive experiment platform according to claim 1, characterized in that: the power amplifier is a low-voltage audio power amplifier LM386. 6. The electrical and electronic technology comprehensive experiment platform according to claim 1, characterized in that: the high-power device interface (9) adopts ULN280× series chips. 7. The comprehensive experiment platform of electrical and electronic technology according to claim 1, characterized in that: said seven-segment digital display (10) adopts chip MC14495. 8. The electrical and electronic technology comprehensive experiment platform according to claim 1, characterized in that: said four-way pulse circuit (22) adopts a Schmitt trigger 74HC14 (1) chip.

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