CN106130434A - A kind of utilize solar powered pump motor control system - Google Patents

Abstract

A water pump motor control system powered by solar energy, including a solar module, a DC-DC boost module, a DC-AC inverter module, a load water pump motor, a PWM control circuit, a voltage detection circuit, a current detection circuit, a power supply unit, and a photovoltaic UI Sampling circuit, CPU control unit and water level detection circuit. The solar module output is connected to the DC‑DC booster module, and the power supply unit provides DC power supply for the PWM control circuit, DC‑AC inverter module and CPU control unit; the DC‑DC booster module is connected to the DC‑AC inverter module, and the DC‑AC inverter module is connected to the DC‑DC The output of the AC inverter module is connected to the load pump motor, the voltage detection circuit and the current detection circuit are connected to the output of the DC-DC step-up module, and the detection signal is sent to the PWM control circuit; the input of the photovoltaic UI sampling circuit is connected to the solar module, and the output is connected to the CPU control unit; The output of the CPU control unit is sent to the DC-AC inverter module; the system has high energy efficiency, strong stability, small system size, and low cost; the structure is versatile and has good promotion and application value.

Description

A water pump motor control system powered by solar energy

technical field

The invention relates to a water pump motor control system powered by solar energy, which belongs to the technical field of solar energy application.

Background technique

In recent years, solar energy application technology has received extensive attention in market application, R&D and production. As a system integrating multiple disciplines and high technologies, the solar water pump system has great practical significance in solving domestic water shortages, farmland irrigation and other occasions. Solar water pump technology can not only realize the sustainable development of energy, but also promote the local economic development and improve the ecological environment.

Usually, the solar water pump system is composed of solar energy conversion and water pump motor control. The corresponding control method is adopted to realize the maximum power output of the solar cell, and the control system controls the work of the water pump motor to realize water intake from deep wells, rivers and other water sources for residents' lives or industrial production. Since the output voltage of solar energy changes continuously with the influence of meteorological factors such as external ambient temperature and light intensity, most of the existing solar water pump control systems using general-purpose controllers have unsatisfactory effects on energy utilization and system stability. Therefore, how to keep the output power of solar modules at the maximum value under the current environment at any time, and adopt corresponding control strategies to achieve efficient and stable operation of the water pump system is a topic worthy of further study.

Contents of the invention

The object of the present invention is to provide a water pump motor control system powered by solar energy to improve the utilization rate of solar energy and realize stable and reliable operation of the system in order to overcome the deficiencies of the prior art.

The technical solution for realizing the present invention is as follows: a water pump motor control system powered by solar energy includes a solar module, a DC-DC boost module, a DC-AC inverter module, a load water pump motor, a PWM control circuit, a voltage detection circuit, and a current detection circuit. circuit, power supply unit, photovoltaic UI sampling circuit, CPU control unit and water level detection circuit.

The entire water pump control system is powered by solar modules, the output of the solar module is connected to the power supply unit, and the output of the other end is connected to the DC-DC step-up module; the power supply unit provides corresponding power for the PWM control circuit, DC-AC inverter module and CPU control unit. DC power supply; DC-DC step-up module output connected to the input of the DC-AC inverter module; DC-AC inverter module output connected to the load pump motor; voltage detection circuit and current detection circuit for collecting DC- The output voltage and current of the DC boost module are input to the PWM control circuit; the input terminal of the photovoltaic UI sampling circuit is connected to the output terminal of the solar module, and the output terminal is connected to the CPU control unit; the water level detection circuit sends the detected water level signal to the CPU In the control unit; the output terminal of the CPU control unit is connected with the DC-AC inverter module.

The DC-DC step-up module adopts a push-pull circuit outputted by full-bridge rectification and filtering, including an input voltage stabilizing capacitor C1, a high-frequency transformer, and a high-voltage power switch tube , ,rectifier diode , , , , an output filter inductor L, and a filter capacitor C2; the DC-DC step-up module is used to step up the DC voltage 48V output by the solar module to a stable output of 350V.

Described PWM control circuit comprises current mode control chip SG3525, peripheral resistance capacitor circuit and the voltage controller that forms with chip LM358, photosensitive coupler; The 2,3 pin input ends of chip LM358 are the voltage small signal of 2.5V, and chip LM358 The output terminal 1 of the photosensitive coupler is connected to the cathode of the light-emitting diode in the photosensitive coupler through the resistor R5; the anode of the light-emitting diode in the photosensitive coupler is connected to +12V working voltage, and the collector of the light-receiving transistor in the photosensitive coupler is connected to the control chip SG3525 through the resistor R22 Pin 2, the emitter of the phototransistor is grounded, and the base is not drawn out; the current signal collected by the current detection circuit is connected to the pin 1 of the control chip SG3525 through the resistor R20, and the pins 5, 6, and 7 are respectively externally connected with capacitors C8, Resistor R33 and resistor R30 determine the sawtooth wave frequency of SG3525, pin 12 is directly grounded, pins 8 and 16 are grounded through C12 and C7 bypass capacitors respectively, pins 13 and 15 are connected to +12V working voltage, pin 11 and lead Pin 14 is the PWM output port of the PWM control circuit, and the output PWM control signal is connected to the DC-DC step-up module.

The DC-AC inverter module is composed of a voltage-type intelligent power module IPM equipped with necessary peripheral hardware circuits, and the 350V stable high voltage output by the DC-DC step-up module is connected to the DC-AC inverter module as its DC input Power supply; the 6-channel PWM signal output by the CPU control unit is connected to the DC-AC inverter module, directly drives the IGBT power tube inside the intelligent power module IPM, and outputs corresponding AC power to connect to the load water pump motor.

The CPU control unit is implemented by a 16-bit microcontroller chip SPMC75F series single-chip microcomputer, which integrates common functional modules such as a high-performance core unit, serial interface, and programmable I/O port. It has strong anti-interference ability and is suitable for motor control applications. , the working voltage is 4.5V~5.5V, and the operation speed is 0~24MHz; the input signal of the CPU control unit is the voltage and current signal collected by the photovoltaic UI sampling circuit and the water level signal collected by the water level detection circuit, and outputs the corresponding PWM The control signal is connected to the DC-AC inverter module.

Described voltage detection circuit is made up of optocoupler OP1A, optocoupler OP1B, operational amplifier A1A, operational amplifier A1B and necessary resistance capacitance; Voltage signal SP end is connected to the anode of light-emitting diode in optocoupler OP1A through resistance R61, voltage signal SN The terminal is connected to the cathode of the light-emitting diode in the optocoupler OP1A through the resistor R62, the collector of the light-receiving transistor in the optocoupler OP1A is connected to the working voltage +12V, and the emitter is grounded through the resistor R63; The emitter of the triode is connected, the negative terminal 2 is connected to the emitter of the optocoupler OP1B light-receiving transistor through the resistor R65, the output terminal of the operational amplifier A1A is connected to the anode of the light-emitting diode in the optocoupler OP1B; the cathode of the light-emitting diode in the optocoupler OP1B is connected to the resistor R64 is grounded, the collector of the phototransistor is connected to the working voltage +12V, the emitter of the phototransistor is grounded through the resistor R66; the positive terminal 5 of the operational amplifier A1B is connected to the cathode of the light-emitting diode in the optocoupler OP1B through the resistor R67, and the negative terminal 6 is connected to the op-amp The output terminal 7 of amplifier A1B is short-circuited, and the output terminal 7 outputs the detected voltage signal and sends it to the PWM control circuit.

The current detection circuit is implemented by a Hall current sensor, and the output is connected to an operational amplifier and a corresponding resistor and capacitor to generate a corresponding current signal and send it to the PWM control circuit.

The current detection circuit is composed of a Hall current sensor, an operational amplifier and corresponding resistors and capacitors; the output of the Hall current sensor is connected to the positive terminal 3 of the operational amplifier through a resistor R42, and the negative terminal 2 of the operational amplifier is short-circuited with the output terminal 1 to form a negative terminal. For feedback, the output terminal 1 of the operational amplifier outputs the collected current signal Id through the resistor R44 and the capacitor C42, and sends it to the PWM control circuit.

The photovoltaic UI sampling circuit is composed of the voltage detection circuit and the current detection circuit, and is used to collect the output voltage and output current of the solar module and input them into the CPU control unit to calculate the solar energy The output power of the module realizes maximum power tracking control.

The power supply unit is a multi-channel output DC power supply composed of the main control chip UC3844, which can realize the 5-way DC power supply 5V, 15V, +12V1, +12V2 and -12V2 output required by the entire system; wherein, the power supply unit The input is provided by the solar module; the 5V output of the power supply unit supplies power to the CPU control unit, the 15V output supplies power to the DC-AC inverter module, and the 12V1 supplies power to the main control chip UC3844 inside the power supply unit , +12V2 and -12V2 output to supply power to other chips.

Compared with the prior art, the beneficial effect of the present invention is: the present invention adopts the CPU control unit realized by the 16-bit micro-controller chip SPMC75F series single-chip microcomputer, forms the DC-AC inverter module with the voltage-type intelligent power module IPM, and is controlled by the main The multi-output DC power supply unit composed of chip UC3844 and the DC-DC boost module with full-bridge rectification and filtering output realize the efficient and stable operation of the control system; the invention discloses a water pump motor control system powered by solar energy. It can adapt to various complex environmental conditions, has high energy utilization rate and good stability; at the same time, the control system structure provided by the invention has versatility, and can meet the variable voltage and frequency control of various application motors, and the system cost is low and economical. Strong practicability and good promotion and application value.

Description of drawings

Fig. 1 is a schematic diagram of the system structure of the present invention;

Fig. 2 is the circuit principle diagram of DC-DC step-up module in the present invention;

Fig. 3 is the circuit schematic diagram of PWM control circuit among the present invention;

Fig. 4 is the circuit schematic diagram of the voltage detection circuit in the present invention;

Fig. 5 is a schematic circuit diagram of the current detection circuit in the present invention.

detailed description

The present invention will be described in detail below in conjunction with the embodiments and with reference to the accompanying drawings.

As shown in Figure 1, a water pump motor control system powered by solar energy, including solar modules, DC-DC booster modules, DC-AC inverter modules, load pump motors, PWM control circuits, voltage detection circuits, and current detection circuits , power supply unit, photovoltaic UI sampling circuit, CPU control unit and water level detection circuit.

The energy supply of the entire water pump motor control system is provided by solar modules, and its output power is related to meteorological factors such as ambient temperature and light intensity. DC step-up module, the other way is introduced into the power supply unit to meet the multi-channel DC power output required by the system. The main circuit of the DC-DC step-up module is a push-pull circuit, which is responsible for stably boosting the DC voltage of the solar module to 350V; the PWM control circuit samples the output voltage and current signals of the DC-DC step-up module through the voltage detection circuit and the current detection circuit , feedback to the control chip SG3525 in the PWM control circuit to generate two complementary PWM drive signals, which are used to control the conduction time of the high-voltage power switch tube of the DC-DC boost module, so that the output voltage is stable at 350V. The photovoltaic UI sampling circuit is used to realize the maximum power tracking of solar modules, that is, the MPPT control part collects the voltage and current signals output by the solar modules through the photovoltaic UI sampling circuit, sends them to the CPU main control unit, and completes the control of solar modules in combination with the corresponding MPPT control algorithm. Maximum power point tracking control; the function of the DC-AC inverter module is based on the voltage space vector (SVPWM) modulation technology to convert the DC high voltage output by the DC-DC step-up module into AC power with variable voltage and frequency. The 6-channel PWM trigger pulse signal generated by the SVPWM waveform generator controls the duty ratio of the power switch tube in the DC-AC inverter module to adjust the output voltage and frequency of the DC-AC inverter module, thereby controlling the output power of the water pump load motor and Torque to adjust the speed of the pump motor; the system load is a centrifugal water pump, which is driven by a three-phase AC asynchronous motor. The water level detection circuit is used to prevent the motor from idling damage caused by the water level falling and the pump cannot pump water. The collected water level signal is sent to the CPU main control unit to control the output of the pulse signal to realize the protection function of the water pump system.

As shown in Figure 2, the DC-DC step-up module adopts a push-pull circuit outputted by full-bridge rectification and filtering, including an input voltage stabilizing capacitor C1, a high-frequency transformer, and a high-voltage power switch tube , ,rectifier diode , , , , output filter inductance L, filter capacitor C2; high frequency transformer , high voltage power switch tube , The on-off control is driven by the drive circuit in PWM mode, and the power switch tube and The drain of the circuit generates a periodic square wave signal, that is, the periodic square wave signal is output at the secondary side of the high-frequency transformer, and a stable 350V DC high voltage is output after a full-bridge rectifier filter circuit. The entire boost module only needs 2 power tubes to realize, the loss is low and the efficiency is high, which greatly reduces the system volume and cost.

As shown in Figure 3, the PWM control circuit includes a current-mode control chip SG3525, a peripheral resistor-capacitor circuit, and is composed of a chip LM358 and a photosensitive coupler; the 2 and 3 pin input terminals of the chip LM358 are small voltage signals of 2.5V, The output terminal 1 of the chip LM358 is connected to the cathode of the light-emitting diode in the photosensitive coupler through the resistor R5; the anode of the light-emitting diode in the photosensitive coupler is connected to the +12V working voltage, and the collector of the light-receiving transistor in the photosensitive coupler is connected to the control chip through the resistor R22 Pin 2 of SG3525, the emitter of the phototransistor is grounded, and the base is not drawn out; the current signal collected by the current detection circuit is connected to pin 1 of the control chip SG3525 through resistor R20, and pins 5, 6, and 7 are respectively connected to external capacitors C8, resistor R33 and resistor R30 determine the sawtooth wave frequency of SG3525, pin 12 is directly grounded, pins 8 and 16 are grounded through C12 and C7 bypass capacitors respectively, pins 13 and 15 are connected to +12V working voltage, pin 11 And pin 14 is the PWM output port of the PWM control circuit, and the output PWM control signal is connected to the DC-DC step-up module.

The voltage error signal is obtained through the voltage detection circuit, and sent to pin 2 of the control chip SG3525 in the PWM control circuit as a given signal of the controller; the output current signal obtained by sampling the current detection circuit is sent to pin 1 of the SG3525 as a feedback signal , the comparison between the two generates an error signal, which is sent to the control chip SG3525 oscillator to generate two complementary PWM drive signals, which are amplified by the operational amplifier and sent to the high-voltage power switch tube in the DC-DC boost module respectively , The grid controls the on-off of the two power transistors. When the output voltage of the DC-DC step-up module increases, the PWM control circuit will control the PWM pulse signal output to be positive for a longer time, so that the conduction time of the power tube is shortened, so that the output voltage of the DC-DC step-up module is stable ,vice versa.

As shown in Figure 4, the voltage detection circuit is composed of optocoupler OP1A, optocoupler OP1B, operational amplifier A1A, operational amplifier A1B and necessary resistors and capacitors; the voltage signal SP end is connected to the light-emitting diode in the optocoupler OP1A through resistor R61 The anode of the voltage signal SN is connected to the cathode of the light-emitting diode in the optocoupler OP1A through the resistor R62, the collector of the phototransistor in the optocoupler OP1A is connected to the working voltage +12V, and the emitter is grounded through the resistor R63; the positive terminal of the operational amplifier A1A is 3 It is connected to the emitter of the phototransistor in the optocoupler OP1A, the negative terminal 2 is connected to the emitter of the photocoupler OP1B phototransistor through the resistor R65, and the output terminal of the operational amplifier A1A is connected to the anode of the light-emitting diode in the optocoupler OP1B; The cathode of the light-emitting diode is grounded through the resistor R64, the collector of the light-receiving triode is connected to the working voltage +12V, the emitter of the light-receiving triode is grounded through the resistor R66; the positive terminal 5 of the operational amplifier A1B is connected to the cathode of the light-emitting diode in the optocoupler OP1B through the resistor R67 , the negative terminal 6 is short-circuited with the output terminal 7 of the operational amplifier A1B, and the output terminal 7 outputs the detected voltage signal and sends it to the PWM control circuit.

As shown in Figure 5, the current detection circuit includes a Hall current sensor, an operational amplifier and a corresponding resistor and capacitor; the output of the Hall current sensor is connected to the positive terminal 3 of the operational amplifier through a resistor R42, and the negative terminal 2 of the operational amplifier is connected to the output terminal 1 is short-circuited to form negative feedback, and the output terminal 1 of the operational amplifier outputs the collected current signal Id through the resistor R44 and the capacitor C42, and sends it to the PWM control circuit. The current detection is realized by Hall current sensor, which has high precision and good dynamic performance.

The invention provides a water pump motor control system powered by solar energy, which can adapt to various complex environmental conditions and realize high energy utilization rate and good stability of the system; at the same time, the system is small in size, low in cost and strong in economical practicability; The structure has versatility, can meet the variable voltage and frequency control of various application motors, and has good popularization and application value.

The unexplained parts involved in the present invention are the same as the prior art or implemented by adopting the prior art.

Claims (6)

1. one kind utilizes solar powered pump motor control system, it is characterised in that described system include solar components, DC-DC boost module, DC-AC inversion module, water load pump motor, pwm control circuit, voltage detecting circuit, current detecting electricity Road, power subsystem, photovoltaic UI sample circuit, CPU control unit and water level detection circuit；

Described solar components outfan connects power subsystem, and other end output is connected to DC-DC boost module；Described power subsystem Corresponding direct-current power supply is provided for pwm control circuit, DC-AC inversion module and CPU control unit；Described DC-DC boosts Module outfan is connected with the input of DC-AC inversion module；Described DC-AC inversion module outfan then loads water pump electricity Machine；The input of described voltage detecting circuit and the input of current detection circuit all connect the outfan of DC-DC boost module, The output of voltage detecting circuit and current detection circuit is connected in pwm control circuit；The input of described photovoltaic UI sample circuit Being connected with solar components outfan, outfan connects CPU control unit；Sensed water level signal is sent by described water level detection circuit To CPU control unit；The outfan of described CPU control unit is connected with DC-AC inversion module.

The most according to claim 1 a kind of utilize solar powered pump motor control system, it is characterised in that described DC-DC boost module uses the push-pull circuit of full-bridge type rectifying and wave-filtering output, including inputting electric capacity of voltage regulation C1, and high frequency transformer, High-voltage circuit breaker pipe,, commutation diode、、、, output inductor L, filter capacitor C2；High frequency transformer In, high-voltage circuit breaker pipe,Break-make is controlled, at power switch pipe with PWM mode excitation by drive circuit WithDrain electrode produce periodic square-wave signal, i.e. high frequency transformer secondary export periodic square-wave signal, through full-bridge Stable 350V DC high voltage is exported after formula current rectifying and wave filtering circuit；DC-DC boost module is for by defeated for described solar components The DC voltage 48V gone out boosts to 350V and stably exports.

The most according to claim 1 a kind of utilize solar powered pump motor control system, it is characterised in that described Pwm control circuit includes current-mode control chip SG3525, peripheral resistor capacitor circuit and with chip LM358, photosensitive coupling The voltage controller of device composition；The 2 of chip LM358,3 pin input end are the voltage small-signals of 2.5V, the output of chip LM358 End 1 is connected to the negative electrode of light emitting diode in photosensitive bonder by resistance R5；In photosensitive bonder the anode of light emitting diode connect+ 12V running voltage, the colelctor electrode of the illuminated triode pin by resistance R22 Access Control chip SG3525 in photosensitive bonder 2, the grounded emitter of illuminated triode, base stage is not drawn；The current signal that described current detection circuit gathers is by resistance R20 The pin 1 of Access Control chip SG3525, pin 5,6,7 external capacitor C8, resistance R33 and resistance R30 respectively, determine SG3525 Sawtooth waveforms frequency, pin 12 is directly grounded, pin 8,16 respectively by C12, C7 shunt capacitance ground connection, pin 13,15 connects+ 12V running voltage, pin 11 and pin 14 are the PWM delivery outlets of pwm control circuit, and output pwm control signal accesses DC- In DC boost module.

The most according to claim 1 a kind of utilize solar powered pump motor control system, it is characterised in that described Voltage detecting circuit is made up of the resistance capacitance of optocoupler OP1A, optocoupler OP1B, amplifier A1A, amplifier A1B and necessity；Voltage Signal SP end is the anode of light emitting diode in resistance R61 accesses optocoupler OP1A, and voltage signal SP end accesses optocoupler through resistance R62 The negative electrode of light emitting diode in OP1A, in optocoupler OP1A, the colelctor electrode of illuminated triode connects running voltage+12V, emitter stage through electricity Resistance R63 ground connection；The anode of amplifier A1A is connected with the emitter stage of illuminated triode in optocoupler OP1A, and negative terminal accesses light through resistance R65 The emitter stage of coupling OP1B illuminated triode, the outfan of amplifier A1A accesses the anode of light emitting diode in optocoupler OP1B；Optocoupler In OP1B, the negative electrode of light emitting diode is through resistance R64 ground connection, and the colelctor electrode of illuminated triode connects running voltage+12V, light three pole The emitter stage of pipe is through resistance R66 ground connection；The anode of amplifier A1B is the negative electrode phase of light emitting diode in resistance R67 and optocoupler OP1B Even, negative terminal and the outfan short circuit of amplifier A1B, the voltage signal of outfan output is delivered in described pwm control circuit.

The most according to claim 1 a kind of utilize solar powered pump motor control system, it is characterised in that described Current detection circuit is made up of Hall current sensor, operational amplifier and corresponding resistor electric capacity；Hall current sensor exports Being connected with the anode of operational amplifier through resistance R42, the negative terminal of operational amplifier forms negative feedback with outfan short circuit, and computing is put The current signal Id that the outfan of big device gathers through resistance R44 electric capacity C42 output, delivers in described pwm control circuit.

The most according to claim 1 a kind of utilize solar powered pump motor control system, it is characterised in that described Power subsystem is the multiple-channel output direct current power supply being made up of Master control chip UC3844, it is possible to needed for realizing whole system inside No. five DC source 5V, 15V ,+12Vl ,+12V2 and-12V2；Wherein, the input of described power subsystem is by described solar energy group Part provides；The 5V of described power subsystem exports and powers to described CPU control unit, and 15V exports and supplies to described DC-AC inversion module Electricity, 12V1 powers to the main control chip UC3844 within described power subsystem, and+12V2 and-12V2 exports to other chip power supplies.