RU184637U1 - Microcontroller for adjusting the flow rate of the cooling liquid of a solar power plant (SEU) - Google Patents

Abstract

The utility model relates to circuitry and can be used to control the flow of coolant in the hydraulic system of a solar power plant (SEC). Microcontroller for adjusting the flow rate of the cooling liquid of a solar power plant, consisting of the analog part of the measuring circuits containing a reference voltage source, an analog multiplexer, a temperature signal amplifier, a flow and temperature measurement circuit, a single-chip microcontroller, a microcontroller control and operability control circuit, an indication and alarm circuit, USB -Interface and AC / DC power supply. In this case, the electronic circuit is made on a printed circuit board installed in an airtight aluminum case, with two pressure glands located on the case, through which the wires for connecting the microcontroller are terminated, ending with terminals, a moisture-proof power switch and a USB socket. The technical result is to increase the degree of protection of the device from dust and moisture.

Description

The proposed utility model relates to circuitry and can be used to control the flow of coolant in the hydraulic system of a solar power plant (SEU) depending on the temperature of the coolant at the output of the solar modules at the locations of the temperature sensors in order to expand the operational capabilities of the SEU by improving the parameters of the microcontroller.

A device for automatically controlling the temperature of the coolant (RF patent No. 7189 from 05/15/1997), containing a temperature sensor located at the outlet of the cooled coolant, energetically connected with the control unit, connected in turn with a modulator acting on the actuator, where the control unit It is made in the form of a microprocessor controller, the modulator is in the form of a purity converter, and the actuator is in the form of an AC electric drive of a fan installed on the supply line the cooling fluid.

The disadvantage of this device is:

- The presence of only one temperature sensor.

- Lack of coolant flow rate sensor.

- Lack of redundancy of the actuator.

- There is no way to connect a PC for the ability to control and view operating modes and parameters of the cooling system.

A known control system of an electric fan for cooling an engine radiator with continuously variable rotation speed (RF patent No. 2229985 dated 04.02.2002), comprising an electric fan, a battery, and the positive terminal of the battery associated with the first output of the electric fan. Additionally, a coolant temperature sensor, a pulse width modulation control unit, a power switch and a diode are introduced into the system. The output of the temperature sensor is connected to the input of the pulse width modulation control unit, the output of which is connected to the control input of the power switch, the first power output of which is connected to the negative of the battery, and the second to the second output of the electric fan and the anode of the diode. Plus, the battery is connected to a pulse width modulation control unit and a diode cathode. The technical result is the unification of the control system of the electric fan for cooling the engine radiator, as well as the ability to maintain the temperature of the engine in the optimal range with high accuracy.

The disadvantage of this device is:

- The presence of only one temperature sensor.

- Lack of coolant flow rate sensor.

- Lack of redundancy of the actuator.

There is no way to connect a PC for the ability to control and view operating modes and parameters of the cooling system.

A control unit for a heating unit is known (RF patent No. 66795 of 01/20/2006), including a control device, a control panel, and a switching unit, while the control device receives information from the sensors of the measured parameters, generates and transmits a control action to the actuating elements through the unit switching, and also receives commands from the control panel, while the supply of voltage to the actuating elements is carried out through the switching unit, characterized in that the device is additionally equipped with about the power supply through which power is supplied to the control panel and the control device, and where the control device has an additional I / O port, to which control commands are received through the modem and information about the operation of the TP is transmitted to the control room.

The purpose of the device is to create comfortable conditions in the premises, regulate the flow of coolant, provide automatic control of the operation of an individual heating unit without the constant presence of maintenance personnel, and ensure economical consumption of thermal energy.

The disadvantage of this device is:

- Lack of coolant flow rate sensor.

- Lack of redundancy of the actuator.

The closest in technical essence to the proposed device is the controller Smart Web S.

The Smart Web S controller consists of a plastic case, an electronic board, control buttons and a 128 × 64 pique graphic LCD. The electronic board processes the signals from three temperature sensors of the ТТТ Pt 1000 type. Depending on the temperature on the sensors, according to a certain algorithm, the parameters of which need to be adjusted, the electronic board controls two outputs: a mechanical relay phase 2A 250V, an analog output.

(The analog output can operate in two modes: in normal mode (0-10V), in PWM mode (1 KHz, 10V). Use the buttons to set the necessary operation parameters of the device. The display shows the Parameters and operating modes of the controller.

11 Smart Web S controller parameters are as follows: mains voltage 220V ± 10%, frequency 50-60 Hz, power consumption ~ 1.5 W, degree of protection according to GOST 15150-IP40, operating ambient temperature from 0 ° С to + 40 ° С, controllers can be combined via the CAN data bus.

The disadvantages of the Smart Web S controller are:

- work with sensors like TCH Pt 1000,

- lack of work with flow / temperature sensors such as VFS (Grundfos),

- a very narrow range of supply voltage

- degree of protection according to GOST 15150-IP40.

The purpose of the proposed utility model is to expand operational capabilities by improving the parameters of the microcontroller.

The technical result is that in the proposed device increases the range of operating ambient temperatures, the range of the supply voltage, and also increases the degree of protection of the device from dust and moisture.

The technical result is achieved in that in a device consisting of an analog part of the measuring circuits containing a reference voltage source, an analog multiplexer, a temperature signal amplifier, a flow and temperature measurement circuit, a single-chip microcontroller, a microcontroller control and operability control circuit, an indication and signaling circuit, USB -interface and AC / DC power supply, work is carried out with temperature sensors and a coolant flow rate sensor due to circuit solutions second analog part of the measuring circuits, followed by the program processing of received data.

In fig. 1 is a functional diagram of a microcontroller for adjusting the flow rate of the cooling liquid of an SEU

Functionally, the electronic circuit of the device consists of the analog part of the measuring circuits (1), a single-chip microcontroller (2), a control and monitoring circuit of the microcontroller (3), an indication and signaling circuit (4), a USB interface (5) and an AC / DC power source (6). The analog part (1) contains the following main components: a voltage reference source, an analog multiplexer, a temperature signal amplifier, flow measurement and VFS sensor temperature measurement circuits.

The electronic circuit is made on a printed circuit board installed in a sealed aluminum case. There are two pressure glands on the case, through which microcontroller connection wires are terminated, ending with round terminals. Also on the case there is a moisture-proof power switch and a hole for connecting a USB cable.

The device operates as follows: the power source (6) from the mains voltage receives a DC voltage of 5 V to power all nodes of the device. The signal from the temperature sensor is fed to the analog part of the measuring circuits (1), or rather to the analog multiplexer, where the signal from the desired sensor is selected for further processing. Next, the selected signal is fed to a temperature signal amplifier for amplification and scaling. Then the signal is fed to one of the ADC channels built into the single-chip microcontroller (2). For operation of the temperature signal amplifier and the ADC, the reference voltage source generates a highly stable voltage of 4.1 V. Also, two more ADC channels, passing through the corresponding measurement circuits, receive signals of the flow rate and temperature from the VFS sensor. These measurement circuits and the reference voltage source are also included in the analog part of the measuring circuits (1). In the ADC of the microcontroller (2), the signals from the temperature sensors and from the flow and temperature sensors VFS are digitized. Then, in the microcontroller (2), using the appropriate software, the values of all temperatures and flow rates are calculated. After calculating the temperatures and flow rates according to the relevant laws and algorithms implemented in the device software, two PWM signals are generated to control the coolant pumps. Also in the microcontroller (2) there is a formation of signals for indication and sound alarm. The USB interface unit (5) converts the UART interface built into the MK into a USB interface for connecting the device to a PC. The control and operability control circuit (3) controls the operation of the microcontroller (2), the indication and signaling circuit (4), and the PWM signal outputs. When the microcontroller (2) fails, the control and operability control circuit (3) switches to the display and signaling circuit (4) and the outputs of the PWM signals, and brings them to the corresponding, predetermined state.

The microcontroller (2), when connected to a PC via USB via a USB socket, has the ability to configure its parameters and control the readings of all sensors and operating modes using specialized software.

The principle of operation of the device is to control two coolant pumps by generating two PWM signals. The parameters of the PWM signals are obtained as a result of measuring the temperature by several sensors and the flow rate of the coolant by one sensor, followed by processing their values in the MC using the appropriate software.

The solution of the problem allows to achieve the following results:

- obtaining a wide range of operating temperatures from -40 ° С to + 80 ° С due to the use of electronic components corresponding to this temperature range;

- obtaining a wide range of supply voltage from 90 V to 260 V through the use of an appropriate AC / DC power source in the device circuit;

- obtaining the degree of protection IP54 in accordance with GOST 15150 due to the representation of the device design in a sealed design.

Claims (1)

Microcontroller for adjusting the flow rate of the cooling liquid of a solar power plant, consisting of the analog part of the measuring circuits containing a reference voltage source, an analog multiplexer, a temperature signal amplifier, a flow and temperature measurement circuit, a single-chip microcontroller, a microcontroller control and operability control circuit, an indication and alarm circuit, USB -interface and AC / DC power source, characterized in that the electronic circuit is made on a printed circuit board installed in ermetichnom aluminum housing, located on the body with two cable glands, which are derived through the MCU to connect the wires terminating terminals, waterproof power switch and USB-socket.

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