Alternating current signal generator

Abstract

The utility model discloses an alternating current signal generator, which is characterized by comprising an alternating current power supply, a transformer, a current transformer, a rectifier, a PWM (Pulse Width Modulation) voltage regulating device, a power resistor, a single chip microcomputer and a metering chip, the alternating current power supply is connected to the high-voltage end of the transformer, and the low-voltage end of the transformer is connected with the PWM voltage regulating device through the rectifier; the PWM voltage regulating device is connected with a power resistor used for consuming power, the primary side of the current transformer is connected to a line where the low-voltage end of the transformer is connected with the rectifier, the secondary side of the current transformer is used for being externally connected with equipment, and the single chip microcomputer is electrically connected with the PWM voltage regulating device and used for controlling the PWM voltage regulating device. The metering chip is connected with the secondary side of the current transformer and the single-chip microcomputer, and is used for collecting the current information of the secondary side and transmitting the current information to the single-chip microcomputer. The device provided by the utility model can adjust the secondary side current of the current transformer as required by utilizing the arrangement of the PWM voltage regulating device and the like, so as to meet the use requirements.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic products, and particularly relates to an alternating current signal generator. Background Art

[0002] In today's society, various electrical appliances have entered thousands of households, and the research work on various power products related to electricity has also increased day by day; among them, the alternating current generating device is used more frequently. In the daily development, design and production process of power equipment products, an alternating current generating device with a size that can be flexibly adjusted is often used as a debugging signal source.

[0003] The traditional alternating current generating device generally has a relatively large volume and complex operation, and is usually only applicable to some specific occasions such as laboratories, and is not convenient to carry around. Moreover, the traditional alternating current generating device is not convenient to adjust the use range of small current, and cannot guarantee the adjustment accuracy of small current, so it cannot meet the use requirements.

[0004] Therefore, there is an urgent need for an alternating current signal generator to solve the problem that the traditional alternating current generating device is not convenient to adjust the use range of small current. Content of the Utility Model

[0005] The utility model aims at the deficiencies in the prior art and provides an alternating current signal generator to solve the problem that the traditional alternating current generating device is not convenient to adjust the use range of small current.

[0006] To achieve the above object, the utility model adopts the following technical solutions:

[0007] An alternating current signal generator, characterized in that it includes an alternating current power supply, a transformer, a current transformer, a rectifier, a PWM voltage regulating device, a power resistor, a single-chip microcomputer and a metering chip. The alternating current power supply is connected to the high-voltage end of the transformer, the low-voltage end of the transformer is connected to the PWM voltage regulating device through the rectifier, the PWM voltage regulating device is connected to the power resistor for consuming power, the primary side of the current transformer is connected to the line where the low-voltage end of the transformer is connected to the rectifier, the secondary side of the current transformer is for external equipment, the single-chip microcomputer is electrically connected to the PWM voltage regulating device for controlling the PWM voltage regulating device, and the metering chip is respectively connected to the secondary side of the current transformer and the single-chip microcomputer for collecting the current information on the secondary side and transmitting it to the single-chip microcomputer.

[0008] To optimize the above technical solution, the specific measures taken further include:

[0009] Further, it also includes an alternating current ammeter. The current terminal of the alternating current ammeter is connected to the secondary side of the current transformer, and the voltage terminal of the alternating current ammeter is connected to the alternating current power supply.

[0010] Further, the UL terminal and the UN terminal of the AC power supply are respectively connected to the UL terminal and the UN terminal of the high-voltage end of the transformer. The lead of the UL1 terminal of the low-voltage end of the transformer passes through the primary side of the current transformer and is connected to the UL1 terminal of the rectifier. The UN1 terminal of the low-voltage end of the transformer is connected to the UN1 terminal of the rectifier. The DC+ terminal of the rectifier is connected to the DC+ of the PWM voltage regulating device, and the DC- terminal of the rectifier is connected to the DC- of the PWM voltage regulating device. The OUT+ terminal and the OUT- terminal of the PWM voltage regulating device are respectively connected to both ends of the power resistor.

[0011] Further, a fuse is connected in series on the line connecting the DC+ terminal of the rectifier and the DC+ of the PWM voltage regulating device.

[0012] Further, the fuse uses an AC220V 3A glass tube fuse.

[0013] Further, the PWM terminal and the GND terminal of the PWM voltage regulating device are respectively connected to the PWM terminal and the GND terminal of the single-chip microcomputer. The communication port of the single-chip microcomputer is connected to the communication port of the metering chip using SPI communication. The acquisition port of the metering chip is connected to the secondary side of the current transformer and acquires the current of the secondary side of the current transformer.

[0014] Further, the PWM voltage regulating device uses a DC MOS field effect transistor module.

[0015] Further, the single-chip microcomputer uses a 32-bit single-chip microcomputer with the chip model of MB9BF218SPMC.

[0016] Further, the single-chip microcomputer is communicatively connected to a communication chip and is connected to a signal converter that can be connected to the computer terminal through the communication chip.

[0017] Further, the single-chip microcomputer is communicatively connected to a Bluetooth module that can be used for wireless connection.

[0018] The beneficial effects of the present utility model are:

[0019] The device of the present utility model transforms voltage through a transformer, converts alternating current into direct current through a rectifier and outputs it, so as to facilitate voltage regulation by a PWM voltage regulation device. The PWM pulse width modulation signal of a single-chip microcomputer controls the PWM voltage regulation device to output the regulated voltage. The power resistor is connected to the PWM voltage regulation device, which can cooperate with the PWM voltage regulation device to consume power to adjust the voltage, and changes the magnitude of the current on the primary side of the current transformer after voltage regulation. The output current on the secondary side is further regulated and changed through the current transformer, that is, as the power of the load circuit unit changes, the current at the output end of the transformer also changes, and the current on the secondary side of the current transformer also changes to meet the usage requirements. When the device of the present utility model is in use, it collects the current of the current transformer through a metering chip and sends the current data to the single-chip microcomputer through SPI communication, so as to facilitate the monitoring and adjustment of the magnitude of current usage, and solves the problem that the traditional alternating current generating device is not convenient to adjust the usage range of small current.

[0020] The device of the present utility model can provide an alternating current that can be flexibly adjusted, and has multiple operation modes such as local operation and remote operation. It is small in size, light in weight and can be carried around. Its simple operation mode, small size, light weight, portability and affordable price do not require professional personnel to operate, saving time and labor costs. Brief Description of the Drawings

[0021] Figure 1 is a schematic structural diagram of an alternating current signal generator proposed by the present utility model;

[0022] Figure 2 is a schematic usage diagram of an alternating current signal generator proposed by the present utility model;

[0023] Figure 3 is a schematic diagram of a specific implementation manner of an alternating current signal generator proposed by the present utility model.

[0024] Reference Numerals: 1. AC ammeter, 2. AC power supply, 3. Transformer, 4. Current transformer, 5. Rectifier, 6. PWM voltage regulation device, 7. Power resistor, 8. Fuse, 9. Single-chip microcomputer, 10. Metering chip, 11. Bluetooth module, 12. Communication chip, 13. Signal converter, 14. Mobile phone terminal, 15. Computer terminal. Detailed Description of the Specific Embodiment

[0025] The present utility model will be described in detail below with reference to the drawings.

[0026] As shown in the atta Figure 1As shown in the figure, an alternating current signal generator according to an embodiment of the present invention includes an alternating current power supply 2, a transformer 3, a current transformer 4, a rectifier 5, a PWM voltage regulating device 6, a power resistor 7, a single-chip microcomputer 9, and a metering chip 10. The alternating current power supply 2 is connected to the high-voltage end of the transformer 3. The low-voltage end of the transformer 3 is connected to the PWM voltage regulating device 6 through the rectifier 5. The PWM voltage regulating device 6 is connected to the power resistor 7 for consuming power. The primary side of the current transformer 4 is connected to the line where the low-voltage end of the transformer 3 is connected to the rectifier 5. The secondary side of the current transformer 4 is for external devices. The single-chip microcomputer 9 is electrically connected to the PWM voltage regulating device 6 for controlling the PWM voltage regulating device 6. The metering chip 10 is respectively connected to the secondary side of the current transformer 4 and the single-chip microcomputer 9 for collecting the current information on the secondary side and transmitting it to the single-chip microcomputer 9.

[0027] The device of the present invention steps down the voltage through the transformer 3, and converts the alternating current into direct current and outputs it through the rectifier 5, so as to facilitate the voltage regulation of the PWM voltage regulating device 6. The PWM voltage regulating device 6 is controlled by the PWM pulse width modulation signal of the single-chip microcomputer 9 to output the regulated voltage. The power resistor 7 is connected to the PWM voltage regulating device 6, which can cooperate with the PWM voltage regulating device 6 to consume power to adjust the voltage, and change the current magnitude on the primary side of the current transformer 4 after voltage regulation. The output current on the secondary side is further regulated and changed through the current transformer 4, that is, as the power of the load circuit unit changes, the current at the output end of the transformer 3 also changes, and the current on the secondary side of the current transformer 4 also changes to meet the usage requirements. When the device of the present invention is in use, the metering chip 10 collects the current of the current transformer 4 and sends the current data to the single-chip microcomputer 9 through SPI communication, so as to facilitate the monitoring and adjustment of the current usage amount, and solves the problem that the traditional alternating current generating device is not convenient to adjust the usage range of small current.

[0028] Moreover, since the current transformer 4 of this device is connected to the output end of the transformer 3, and the input end of the transformer 3 is the alternating current power supply 2 of the commercial power, it can be ensured that the current generated by the current transformer 4 of this device is of the same frequency and phase as the current generated in the commercial power, which can help power R & D personnel better debug and develop products.

[0029] In another specific embodiment, it further includes an alternating current meter 1. The current terminal of the alternating current meter 1 is connected to the secondary side of the current transformer 4, and the voltage terminal of the alternating current meter 1 is connected to the alternating current power supply 2. In this way, when in use, the alternating current meter 1 can be used as a display device to respectively detect and display the corresponding voltage and current.

[0030] In another specific embodiment, the UL terminal and the UN terminal of the AC power supply 2 are respectively connected to the UL terminal and the UN terminal of the high-voltage end of the transformer 3. The lead of the UL1 terminal of the low-voltage end of the transformer 3 passes through the primary side of the current transformer 4 and is connected to the UL1 terminal of the rectifier 5. The UN1 terminal of the low-voltage end of the transformer 3 is connected to the UN1 terminal of the rectifier 5. The DC+ terminal of the rectifier 5 is connected to the DC+ of the PWM voltage regulating device 6, and the DC- terminal of the rectifier 5 is connected to the DC- of the PWM voltage regulating device 6. The OUT+ terminal and the OUT- terminal of the PWM voltage regulating device 6 are respectively connected to both ends of the power resistor 7.

[0031] Among them, a fuse 8 is connected in series on the line where the DC+ terminal of the rectifier 5 is connected to the DC+ of the PWM voltage regulating device 6, which can play a role in protecting the circuit when overloaded. Among them, the fuse 8 can adopt an AC220V 3A glass tube fuse.

[0032] In another specific embodiment, the PWM terminal and the GND terminal of the PWM voltage regulating device 6 are respectively connected to the PWM terminal and the GND terminal of the single-chip microcomputer 9. The communication port of the single-chip microcomputer 9 and the communication port of the metering chip 10 are connected by SPI communication. The acquisition port of the metering chip 10 is connected to the secondary side of the current transformer 4 and acquires the current on the secondary side of the current transformer 4.

[0033] In the above embodiment, the PWM voltage regulating device 6 can adopt a DC MOS tube field effect tube module. The single-chip microcomputer 9 can adopt a 32-bit single-chip microcomputer with the chip MB9BF218SPMC, and the metering chip 10 can adopt an ATT7022E metering chip.

[0034] As shown in the appendix Figure 2 In another specific embodiment, the single-chip microcomputer 9 is communicatively connected to the communication chip 12 and is connected to the signal converter 13 that can be connected to the computer terminal 15 through the communication chip 12. Among them, the communication chip 12 can adopt an SN65HVD2082ED communication chip, and the signal converter 13 adopts a 485 signal converter.

[0035] In this way, when in use, after being processed by the single-chip microcomputer 9, it is sent to the SN65HVD2082ED communication chip through 485 communication. After being processed by the communication chip 12, it is sent to the 485 signal converter through its A port and B port. Finally, the 485 signal converter is connected to the computer terminal through the USB port to communicate and exchange information.

[0036] In another specific embodiment, the single-chip microcomputer 9 is communicatively connected to the Bluetooth module 11 that can be wirelessly connected to the mobile phone terminal 14. Among them, the Bluetooth module 11 can adopt an HC-05 Bluetooth module.

[0037] Therefore, during use, after being processed by the single-chip microcomputer 9, the data information processed by the single-chip microcomputer 9 can be connected to the external HC-05 Bluetooth module through UART communication, and after being processed by the HC-05 Bluetooth module, it can communicate with the mobile phone terminal wirelessly.

[0038] During use of the present utility model, the user can send command information to the single-chip microcomputer 9 through a computer terminal or a mobile phone terminal to adjust the magnitude of the secondary side current of the current transformer 4, thereby facilitating the R & D and debugging of products by power R & D personnel and enabling local operation or remote APP operation as needed; since the device is provided with a metering chip 10, etc., the amount of current calibrated by the user can be displayed on the computer terminal or the mobile phone terminal at all times, which is beneficial for the user to perform specific current settings.

[0039] As shown in the Figure 3 accompanying figure, in a specific implementation manner of this solution, leads are connected from the UL terminal and the UN terminal of the AC power supply 2 of the commercial power to both ends of the high-voltage side of the transformer 3. After being stepped down by the transformer 3 to output AV6V, the UL1 line at the output end of the transformer 3 passes through the current transformer 4 and is connected to the UL1 input end of the rectifier 5, and the UN1 of the transformer 3 is connected to the UN1 input end of the rectifier 5; the rectifier 5 converts the alternating current into direct current DC6V for output. The DC+ output end of the rectifier 5 is connected to the DC+ of the PWM voltage regulating device 6, and a fuse 8 is connected in series between them to play a role in protecting the circuit against overload. The DC- of the rectifier 5 is connected to the DC- of the PWM voltage regulating device 6. The PWM and GND ports of this PWM voltage regulating device 6 are respectively connected to the PWM and GND ports of the MB9BF218SPMC single-chip microcomputer. The PWM pulse width modulation signal of the single-chip microcomputer 9 is used to control the PWM voltage regulating device 6 to output a high-precision DC0 to 6V voltage. The OUT+ and OUT- ports at the output end of the PWM voltage regulating device 6 are connected in series with a voltage gold power resistor 3Ω100W to form a load circuit loop, which plays a role in power consumption, thereby affecting the magnitude of the output of the current transformer 4 and playing a role in assisting power R & D personnel in R & D and debugging products.

[0040] Among them, considering that it is necessary to reduce the power consumption of the load circuit and the output voltage of the transformer 3 can enable the PWM voltage regulating device 6 to work properly in terms of the transformer 3, a transformer with an AC voltage of 220V stepped down to 6V and a power output of 20VA can be selected in consideration of the above. In this way, the output current of the transformer 3 passing through the opening of the current transformer 4 can be increased from an AC current of 0A to a maximum of 3A. The red wire of the transformer 3 is the input end of the AC 220V, and the green wire is the output end of the AC 6V.

[0041] Among them, the current transformer 4 selected is of the 50 / 5A model. In order to make the secondary current generated by the current transformer 4 about twice the primary current, the wire at the output end of the transformer needs to pass through the opening of the current transformer 20 turns. In this way, if the current at the output end of the transformer 3 is 1A, the current on the secondary side of the current transformer 4 can reach about 2A.

[0042] Among them, the voltage at the output end of the transformer 3 is rectified by a rectifier bridge into a DC 6V voltage, and a fuse 8 is connected in series and then connected to the voltage input port of the PWM voltage regulation device 6. In the whole circuit, in case of overload or short circuit, the fuse 8 will be preferentially blown to protect the normal use of each unit module in the circuit later.

[0043] Among them, the DC 6V voltage rectified by the rectifier bridge is connected to the voltage input port of the PWM voltage regulation device 6, and then the voltage output of the PWM voltage regulation device 6 is controlled by the PWM pulse width modulation signal of the single-chip microcomputer system. After experimental debugging, when there is no load at the output end of the PWM voltage regulation device 6, the adjustable range of the output voltage is 0 to 6V. When a 3Ω gold power resistor is connected to the output end, the adjustable range of the output voltage is 0 to 4V. This PWM voltage regulation device 6 can adopt a MOS tube structure of 4 ME60N03. The input voltage range of its module is within 0 to 30V and the current is within 5A, the output voltage range is within 0 to 30V and the current is within 5A, the input voltage range of the PWM modulation signal is 0 to 5V and the current is 5mA, the frequency range of the PWM is 0 to 20KHZ, and it has four input and four output ports, which is very suitable for output control of high-power devices. For example, controlling the brightness of an LED light, controlling the speed of a DC motor, controlling the direction and speed of a stepper motor, etc.

[0044] The communication port of the metering chip 10 is connected to the communication port of the single-chip microcomputer 9 using SPI communication. The acquisition ports V1P and V1N pins of the metering chip 10 collect the current of the current transformer 4, and send the current data to the single-chip microcomputer 9 through SPI communication. After being processed by the single-chip microcomputer 9, it is sent to the SN65HVD2082ED communication chip through 485 communication. After being processed by the 485 communication chip, it is sent to the 485 signal converter through ports A and B. Finally, the 485 signal converter is connected to the computer terminal through the USB port to communicate with each other. In addition, the data information processed by the single-chip microcomputer 9 can be connected to an external HC-05 Bluetooth module through UART communication, and after being processed by the HC-05 Bluetooth module, it communicates wirelessly with the mobile phone terminal.

[0045] Among them, in the single-chip microcomputer system, the 32-bit single-chip microcomputer chip MB9BF218SPMC is used as the core, and the metering and acquisition chip ATT7022E continuously collects the current on the secondary side of the instrument current transformer 4 inside the instrument, and displays it on the mobile phone or computer through HC-05 Bluetooth communication or the 485 communication chip SN65HVD3082ED. According to the existing current value of the instrument, the user can send instructions to the single-chip microcomputer system through the computer or mobile phone, and after being processed by the single-chip microcomputer system, a PWM signal is sent to adjust the magnitude of the current generated by the current signal generator.

[0046] In this embodiment, the PWM voltage regulation device 6 can adopt a DC field-effect transistor drive module. For this DC voltage regulation module, its output terminal can adjust the voltage without connecting a power resistor, etc., and has a very high precision, which can achieve an adjustment from 0 to 6V, that is to say, its output voltage can reach the 0.01V standard or even lower. At the same time, it can also be controlled by the PWM signal.

[0047] In this solution, in order to enable the PWM voltage regulation device 6 to work properly, the input terminal of the PWM voltage regulation device 6 is rectified by the rectifier 5, and the AC 6V alternating voltage at the output terminal of the transformer 3 is rectified and converted into a DC 6V direct current voltage, so that the field-effect transistor drive module can work smoothly.

[0048] In this solution, in order to achieve the purpose of changing the power consumption of the PWM voltage regulation device 6, according to the power formula P = U^2 / R, the higher the voltage regulation accuracy, the higher the generated power W. According to the law of conservation of energy, the input power and output power of the PWM voltage regulation device 6 are the same. By analogy, the input power and output power of the rectifier 5 are also the same. The difference is that the output terminal of the PWM voltage regulation device 6 is direct current, while the input terminal of the rectifier 5 is alternating current, but their powers are the same. Therefore, when the output power of the PWM voltage regulation device 6 changes with high precision, the input power of the rectifier 5 also changes synchronously with high precision. Since the output voltage U at the output terminal of the transformer 3 is a fixed value of 6V, then according to the power formula P = UI, when U is constant and P changes, then I will change accordingly, and this I is the primary side alternating current of the current transformer 4, and the secondary side current of the corresponding current transformer 4 can also change with high precision correspondingly.

[0049] The device of the present utility model can provide an alternating current that can be flexibly adjusted, and has multiple operation modes including local operation and remote operation. It is small in size and light in weight, and can be carried around. Its simple operation mode, small size, light weight, portability and affordable price do not require professional personnel to operate, saving time and labor costs. In the daily development, design and production process of power equipment, alternating current signals that need to be flexibly adjusted in magnitude are often used. The device of the present utility model can meet the flexible adjustment of the magnitude of the alternating current signal, can flexibly obtain alternating current signals with various values, and has multiple operation modes including local operation and remote operation. The whole operation process is simple and flexible, the overall volume is small, the weight is light, and it is a portable alternating current signal generator.

[0050] It should be noted that the terms such as "upper", "lower", "left", "right", "front", "rear", etc. cited in the utility model are only for the convenience of description and are not used to limit the scope of implementation of the present utility model. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope of implementation of the present utility model.

[0051] The above is only the preferred implementation mode of the present utility model. The protection scope of the present utility model is not limited to the above embodiments. All technical solutions falling within the idea of the present utility model belong to the protection scope of the present utility model. It should be pointed out that for those of ordinary skill in the art in this technical field, several improvements and refinements made without departing from the principle of the present utility model should be regarded as the protection scope of the present utility model.

Claims

1. An alternating current signal generator, characterized in that: It includes an AC power supply (2), a transformer (3), a current transformer (4), a rectifier (5), a PWM voltage regulating device (6), a power resistor (7), a single-chip microcomputer (9) and a metering chip (10). The AC power supply (2) is connected to the high-voltage end of the transformer (3). The low-voltage end of the transformer (3) is connected to the PWM voltage regulating device (6) through the rectifier (5). The PWM voltage regulating device (6) is connected to the power resistor (7) for consuming power. The primary side of the current transformer (4) is connected to the line where the low-voltage end of the transformer (3) is connected to the rectifier (5). The secondary side of the current transformer (4) is for external devices. The single-chip microcomputer (9) is electrically connected to the PWM voltage regulating device (6) for controlling the PWM voltage regulating device (6). The metering chip (10) is respectively connected to the secondary side of the current transformer (4) and the single-chip microcomputer (9) for collecting the current information on the secondary side and transmitting it to the single-chip microcomputer (9).

2. The alternating current signal generator according to claim 1, wherein: It further includes an AC ammeter (1). The current terminal of the AC ammeter (1) is connected to the secondary side of the current transformer (4), and the voltage terminal of the AC ammeter (1) is connected to the AC power supply (2).

3. The alternating current signal generator according to claim 1, characterized in that: The UL terminal and the UN terminal of the AC power supply (2) are respectively connected to the UL terminal and the UN terminal of the high-voltage end of the transformer (3). The lead of the UL1 terminal of the low-voltage end of the transformer (3) passes through the primary side of the current transformer (4) and is connected to the UL1 terminal of the rectifier (5). The UN1 terminal of the low-voltage end of the transformer (3) is connected to the UN1 terminal of the rectifier (5). The DC+ terminal of the rectifier (5) is connected to the DC+ of the PWM voltage regulating device (6), and the DC- terminal of the rectifier (5) is connected to the DC- of the PWM voltage regulating device (6). The OUT+ terminal and the OUT- terminal of the PWM voltage regulating device (6) are respectively connected to both ends of the power resistor (7).

4. An alternating current signal generator according to claim 3, characterized in that: A fuse (8) is connected in series on the line where the DC+ terminal of the rectifier (5) is connected to the DC+ of the PWM voltage regulating device (6).

5. An alternating current signal generator according to claim 4, characterized in that: The fuse (8) uses an AC220V 3A glass tube fuse.

6. An alternating current signal generator according to claim 1, characterized in that: The PWM terminal and the GND terminal of the PWM voltage regulating device (6) are respectively connected to the PWM terminal and the GND terminal of the single-chip microcomputer (9). The communication port of the single-chip microcomputer (9) and the communication port of the metering chip (10) are connected by SPI communication. The acquisition port of the metering chip (10) is connected to the secondary side of the current transformer (4) and collects the current on the secondary side of the current transformer (4).

7. An alternating current signal generator according to claim 1, characterized in that: The PWM voltage regulating device (6) uses a DC MOS field effect transistor module.

8. An alternating current signal generator according to claim 1, wherein: The single-chip microcomputer (9) uses a 32-bit single-chip microcomputer with the chip MB9BF218SPMC.

9. The alternating current signal generator according to claim 1, characterized in that: The single-chip microcomputer (9) is communicatively connected to a communication chip (12) and is connected to a signal converter (13) that can be connected to a computer terminal (15) through the communication chip (12).

10. The alternating current signal generator according to claim 1, wherein: The single-chip microcomputer (9) is communicatively connected to a Bluetooth module (11) for wireless connection.

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