Fan speed regulation circuit of energy storage inverter

Abstract

The utility model relates to a fan speed regulation circuit of an energy storage inverter, which belongs to the technical field of inverters and comprises a digital signal processor (DSP) control module, a temperature detection module, a fan driving module, a rotating speed detection module and a direct current power supply. Wherein the temperature detection module is electrically connected with a temperature signal input end IO3 of the DSP control module; one end of the fan driving module is electrically connected with the control signal output end IO1 of the DSP control module, and the other end of the fan driving module is electrically connected with the PWM signal input end of the fan; one end of the rotating speed detection module is electrically connected with a rotating speed feedback signal input end IO2 of the DSP control module, and the other end of the rotating speed detection module is electrically connected with a Speed signal output end of the fan; inverter internal temperature signals collected by the temperature detection module and fan Speed signals obtained by the rotating speed detection module are transmitted to the DSP control module in real time, and the DSP control module outputs control PWM signals to drive a fan motor to operate. The utility model has the advantages of state monitoring and strong anti-interference capability.

Description

Technical Field

[0001] This utility model belongs to the field of inverter technology, specifically relating to a fan speed control circuit for an energy storage inverter. Background Technology

[0002] During operation, energy storage inverters generate a significant amount of heat from their internal power semiconductor devices (such as IGBTs and MOSFETs). Insufficient heat dissipation can lead to increased junction temperatures, affecting efficiency and lifespan, or even causing overheating damage and system failure. Forced air cooling via fans is generally required, so the quality of fan control directly impacts heat dissipation, system reliability, and overall energy consumption.

[0003] However, the existing fan drive solutions currently in use typically have the following shortcomings:

[0004] The control method is crude: many solutions use simple temperature control switches or fixed duty cycle PWM control, which cannot make smooth and precise speed adjustment according to the continuous changes in the internal temperature of the inverter. This results in either insufficient heat dissipation or the fan running at high speed for a long time, generating unnecessary noise and shortening the fan's life.

[0005] Lack of effective feedback and fault diagnosis: Most open-loop control schemes cannot obtain real-time information about the actual operating status of the fan (such as whether it is running or whether the speed is normal). Once the fan fails due to stalling, aging, or cable detachment, the control system cannot detect it in time and continues to operate under high load, which can easily lead to overheating and damage to the equipment, posing a safety hazard.

[0006] Weak anti-interference capability: There is strong electromagnetic interference inside the inverter. If the drive signal and speed feedback signal are not isolated, they are easily interfered with, which may lead to DSP misjudgment or damage, affecting control stability and system reliability.

[0007] Low level of intelligence: It fails to form a closed-loop intelligent control system that integrates temperature monitoring, fan drive, and speed feedback, making it impossible to dynamically optimize heat dissipation strategies based on actual heat load, resulting in relatively low energy efficiency. Utility Model Content

[0008] The purpose of this invention is to address the problems existing in the prior art by providing a fan speed control circuit for an energy storage inverter. This circuit achieves precise closed-loop control through optocoupler isolation and provides a highly reliable fan drive with status monitoring and strong anti-interference capabilities.

[0009] The technical solution is as follows:

[0010] A fan speed control circuit for an energy storage inverter includes a DSP control module, a temperature detection module, a fan drive module, a speed detection module, and a DC power supply. The temperature detection module is electrically connected to the temperature signal input terminal IO3 of the DSP control module. One end of the fan drive module is electrically connected to the control signal output terminal IO1 of the DSP control module, and the other end is electrically connected to the PWM signal input terminal of the fan. One end of the speed detection module is electrically connected to the speed feedback signal input terminal IO2 of the DSP control module, and the other end is electrically connected to the Speed ​​signal output terminal of the fan. The DC power supply is divided into three parts: S_1 connected to the fan, S_2 connected to the fan drive module, and S_3 connected to the speed detection module. The internal temperature signal of the inverter collected by the temperature detection module and the fan Speed ​​signal obtained by the speed detection module are transmitted in real time to the DSP control module, which then outputs a control PWM signal to drive the fan motor.

[0011] Furthermore, the fan drive module includes resistors R1-R7, transistor Q1, and a TO-5 packaged optocoupler PC1. The anode pin of the optocoupler is connected to the DC power supply S_1 via resistor R1. Its cathode pin is connected to the IO1 of the DSP control module via resistor R3. Its positive power supply pin Vcc is connected to the DC power supply S_1 and then connected to the PWM signal input terminal of the fan and transistor Q1 via resistor R4. Its output voltage pin Vout is connected to transistor Q1 via resistor R6, and its negative power supply pin Vee is grounded. Resistor R2 is connected in parallel between the anode and cathode pins of the optocoupler. Resistor R4 is connected in series with resistor R5 and then grounded. Resistor R6 is connected in parallel with the grounded terminal of transistor Q1 via resistor R7. The PWM signal output from the IO1 of the DSP control module is isolated and output through optocoupler PC1 to drive the fan motor.

[0012] Furthermore, transistor Q1 is an NPN transistor, with its collector connected to the PWM signal input terminal of the fan, its emitter grounded, and its control terminal connected to the junction of resistors R6 and R7.

[0013] Furthermore, transistor Q1 is an N-channel MOSFET, with its drain connected to the PWM signal input terminal of the fan, its source grounded, and its gate connected to the junction of resistors R6 and R7.

[0014] Furthermore, the speed detection module includes resistors R8-R10 and a TO-4 packaged optocoupler PC2. The collector pin of the optocoupler is connected to IO2 of the DSP control module and connected to the DC power supply S_3 through resistor R8. Its emitter pin is grounded, its anode pin is connected to the DC power supply S_1, and its cathode pin is connected to the fan's speed signal output terminal after being connected in series with resistor R10. A resistor R9 is connected in parallel between the anode and cathode pins of the optocoupler. The speed pulse signal generated when the fan is running is converted into a pulse signal by the optocoupler and input to IO2 of the DSP control module, which calculates the actual speed of the fan based on the pulse frequency.

[0015] Furthermore, the temperature detection module sets up multiple temperature measurement points inside the energy storage inverter and collects temperature data through temperature sensors. The DSP control module compares the temperature data, the actual fan speed signal, and the preset temperature-speed curve to output different PWM signals.

[0016] Beneficial effects:

[0017] 1) Based on the internal temperature of the inverter, the DSP control module generates a PWM signal to control the fan and simultaneously collects the actual fan speed signal for feedback comparison and adjustment, thereby realizing stepless smooth adjustment of the fan speed. This ensures that the heat dissipation capacity is accurately matched with the actual heat load, avoiding the risk of overheating and significantly reducing the speed at low temperatures or light loads, reducing fan wear, lowering operating noise and saving energy.

[0018] 2) Both the fan drive module and the speed detection module adopt optocoupler isolation design, which realizes electrical isolation between the DSP control module and the fan drive circuit, effectively prevents interference such as power supply noise from entering the control core, protects the DSP control module, and enhances the system's stable operation capability in complex electromagnetic environments. Attached Figure Description

[0019] Figure 1 This is the complete circuit diagram of this utility model;

[0020] Figure 2 This is a schematic diagram illustrating the principle of this utility model in application.

[0021] Figure 3 The circuit diagram for transistor Q1 in the fan drive module is a bipolar transistor.

[0022] Figure 4 The circuit diagram shows that transistor Q1 in the fan drive module uses a MOSFET.

[0023] Figure 5 This is the circuit diagram for the speed detection module. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not intended to limit it. Terms such as "upper," "lower," "front," "rear," "left," "right," "bottom," "inner," and "outer," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the utility model. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the utility model.

[0025] like Figures 1 to 2 The circuit shown is a fan speed control circuit for an energy storage inverter, including a DSP control module, a temperature detection module, a fan drive module, a speed detection module, and a DC power supply. The temperature detection module is electrically connected to the temperature signal input terminal IO3 of the DSP control module. One end of the fan drive module is electrically connected to the control signal output terminal IO1 of the DSP control module, and the other end is electrically connected to the PWM signal input terminal of the fan. One end of the speed detection module is electrically connected to the speed feedback signal input terminal IO2 of the DSP control module, and the other end is electrically connected to the Speed ​​signal output terminal of the fan. The DC power supply is divided into three parts: S_1 connected to the fan, S_2 connected to the fan drive module, and S_3 connected to the speed detection module. The internal temperature signal of the inverter collected by the temperature detection module and the fan Speed ​​signal obtained by the speed detection module are transmitted in real time to the DSP control module, which then outputs a control PWM signal to drive the fan motor.

[0026] like Figure 3 or Figure 4As shown, the fan drive module includes resistors R1-R7, transistor Q1, and a TO-5 packaged optocoupler PC1. The anode pin of the optocoupler is connected to the DC power supply S_1 via resistor R1. Its cathode pin is connected to the IO1 of the DSP control module via resistor R3. Its positive power supply pin Vcc is connected to the DC power supply S_1 and, via resistor R4, to the PWM signal input of the fan and transistor Q1. Its output voltage pin Vout is connected to transistor Q1 via resistor R6, and its negative power supply pin Vee is grounded. Resistor R2 is connected in parallel between the anode and cathode pins of the optocoupler. Resistor R4 is connected in series with resistor R5 and then grounded. Resistor R6 is connected in parallel with the grounded terminal of transistor Q1 via resistor R7. The PWM signal output from the IO1 of the DSP control module is isolated and output through optocoupler PC1 to drive the fan motor. When transistor Q1 is an NPN transistor, its collector is connected to the PWM signal input of the fan, its emitter is grounded, and its control electrode is connected to the junction of resistors R6 and R7. When transistor Q1 is an N-channel MOSFET, its drain is connected to the PWM signal input terminal of the fan, its source is grounded, and its gate is connected to the junction of resistors R6 and R7.

[0027] like Figure 5 As shown, the speed detection module includes resistors R8-R10 and a TO-4 packaged optocoupler PC2. The collector pin of the optocoupler is connected to IO2 of the DSP control module and to the DC power supply S_3 through resistor R8. Its emitter pin is grounded, its anode pin is connected to the DC power supply S_1, and its cathode pin is connected to the fan's speed signal output terminal after being connected in series with resistor R10. A resistor R9 is connected in parallel between the anode and cathode pins of the optocoupler. The speed pulse signal generated by the fan during operation is converted into a pulse signal by the optocoupler and input to IO2 of the DSP control module, which calculates the actual speed of the fan based on the pulse frequency.

[0028] The temperature detection module sets up multiple temperature measurement points in the energy storage inverter and collects temperature data through temperature sensors. The DSP control module compares the temperature data, the actual fan speed signal and the preset temperature-speed curve, and outputs different PWM signals.

[0029] The fan's PWM is the PWM signal output terminal, Speed ​​is the speed signal output terminal, U+ is the positive terminal of DC power supply, and U- is the negative terminal of DC power supply; the optocoupler PC1's Anode is the anode pin, Cathode is the cathode pin, Vcc is the positive power supply pin, Vout is the output voltage pin, and Vee is the negative power supply pin; the optocoupler PC2's Anode is the anode pin, Cathode is the cathode pin, Collector is the collector pin, and Emitter is the emitter pin.

[0030] Example: A heat sink is installed on the DC / DC module of the energy storage inverter. The fan of the heat sink is controlled by the speed control circuit of this invention. The temperature detection module has multiple temperature measurement points set within the energy storage inverter, and temperature data is collected by a temperature sensor (NTC). The DSP control module acts as the control core, processing temperature information, calculating the fan speed, and generating PWM. At least one GPIO port is configured as a control signal output terminal (IO1) for outputting a PWM wave; at least one GPIO port is configured as a speed feedback signal input terminal (IO2) for receiving pulse signals characterizing the fan speed; and at least one GPIO port is configured as a temperature signal input terminal (IO3). The input terminal of the fan drive module, isolated by the optocoupler PC1, is connected to the IO1 pin of the DSP control module through a current-limiting resistor to control the PWM signal. Its output side is connected between the DC power supply S_1 and the PWM signal input of the fan motor. When IO1 outputs a low-level PWM pulse, the optocoupler conducts, the transistor conducts, and both the drain and source voltages are 0V, so the fan motor does not rotate. Conversely, when IO1 outputs a high level or is left floating, the fan motor rotates at full speed. By changing the PWM duty cycle, the average voltage applied to the fan is effectively adjusted, thereby controlling its speed.

[0031] The fan's built-in or external Hall sensor or frequency generator outputs a pulse signal proportional to its rotational speed. This signal is connected to the input side of the optocoupler PC2 in the speed detection module. The collector of the optocoupler's output side is connected to the DC power supply S_3 via a pull-up resistor, and the emitter is grounded. The collector output is the speed feedback signal IO2, which is sent to the IO2 pin of the DSP control module. Each rotation of the fan generates a fixed number of pulses. The DSP control module calculates the real-time speed by measuring the frequency of the pulses on the IO2 pin. The DSP control module receives the inverter's internal temperature signal from the temperature detection module and the fan's Speed ​​signal from the speed detection module. Based on the inverter's internal temperature, the DSP control module generates a PWM signal to control the fan, causing the fan speed to increase or decrease accordingly. Simultaneously, it collects the actual fan speed signal for feedback comparison and adjustment. If the actual fan speed is detected to be below the set value, the DSP control module promptly outputs an alarm signal, or directly sends a shutdown signal when the energy storage inverter's switching signal is also connected to the DSP control module. This forms a complete intelligent closed-loop control system for fan speed control, ensuring the safety of the energy storage inverter.

[0032] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the principles and spirit of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A fan speed control circuit for an energy storage inverter, characterized in that: The system includes a DSP control module, a temperature detection module, a fan drive module, a speed detection module, and a DC power supply. The temperature detection module is electrically connected to the temperature signal input terminal IO3 of the DSP control module. One end of the fan drive module is electrically connected to the control signal output terminal IO1 of the DSP control module, and the other end is electrically connected to the PWM signal input terminal of the fan. One end of the speed detection module is electrically connected to the speed feedback signal input terminal IO2 of the DSP control module, and the other end is electrically connected to the Speed ​​signal output terminal of the fan. The DC power supply is divided into three parts: S_1 connected to the fan, S_2 connected to the fan drive module, and S_3 connected to the speed detection module. The inverter's internal temperature signal collected by the temperature detection module and the fan Speed ​​signal obtained by the speed detection module are transmitted in real time to the DSP control module, which then outputs a control PWM signal to drive the fan motor.

2. The fan speed control circuit of the energy storage inverter as described in claim 1, characterized in that: The fan drive module includes resistors R1-R7, transistor Q1, and a TO-5 packaged optocoupler PC1. The anode pin of the optocoupler is connected to the DC power supply S_1 via resistor R1. Its cathode pin is connected to the IO1 of the DSP control module via resistor R3. Its positive power supply pin Vcc is connected to the DC power supply S_1 and then connected to the PWM signal input terminal of the fan and transistor Q1 via resistor R4. Its output voltage pin Vout is connected to transistor Q1 via resistor R6, and its negative power supply pin Vee is grounded. Resistor R2 is connected in parallel between the anode and cathode pins of the optocoupler. Resistor R4 is connected in series with resistor R5 and then grounded. Resistor R6 is connected in parallel with the grounded terminal of transistor Q1 via resistor R7. The PWM signal output from the IO1 of the DSP control module is isolated and output through optocoupler PC1 to drive the fan motor.

3. The fan speed control circuit of the energy storage inverter as described in claim 2, characterized in that: The transistor Q1 is an NPN transistor, with its collector connected to the PWM signal input terminal of the fan, its emitter grounded, and its control electrode connected to the junction of resistors R6 and R7.

4. The fan speed control circuit of the energy storage inverter as described in claim 2, characterized in that: The transistor Q1 is an N-channel MOSFET, with its drain connected to the PWM signal input terminal of the fan, its source grounded, and its gate connected to the junction of resistors R6 and R7.

5. The fan speed control circuit of the energy storage inverter as described in claim 1, characterized in that: The speed detection module includes resistors R8-R10 and a TO-4 packaged optocoupler PC2. The collector pin of the optocoupler is connected to IO2 of the DSP control module and is connected to DC power supply S_3 through resistor R8. Its emitter pin is grounded, its anode pin is connected to DC power supply S_1, and its cathode pin is connected to the fan's speed signal output terminal after being connected in series with resistor R10. A resistor R9 is connected in parallel between the anode and cathode pins of the optocoupler. The speed pulse signal generated when the fan is running is converted into a pulse signal by the optocoupler and input to IO2 of the DSP control module, which calculates the actual speed of the fan based on the pulse frequency.

6. The fan speed control circuit of the energy storage inverter as described in claim 1, characterized in that: The temperature detection module sets up multiple temperature measurement points in the energy storage inverter and collects temperature data through temperature sensors. The DSP control module compares the temperature data, the actual fan speed signal and the preset temperature-speed curve, and outputs different PWM signals.

Images