IGBT fixed-frequency voltage-regulating constant-current energy-saving device

Abstract

The invention relates to the technical field of power electronics, and discloses an IGBT (Insulated Gate Bipolar Translator) fixed-frequency voltage-regulating constant-current energy-saving device, which comprises a power supply module, an IGBT power module, a current sampling module, a driving module, a control module, a motor and a voltage acquisition module, the current sampling module is connected in series between the IGBT power module and a load, collects load current in real time and outputs a current feedback signal, and the driving module is used for outputting a driving signal with dead time to the IGBT power module. According to the invention, the effects that the dead time of the driving module is not fixed, the dynamic change of the load current is adapted and the energy-saving effect and the device stability are not influenced are realized, and the problems that the dead time of the driving module is fixed, the dynamic change of the load current cannot be adapted, the switching loss or the commutation peak is easy to generate and the power consumption is low in the prior art are solved. And the energy-saving effect and the stability of the device are influenced.

Description

IGBT Fixed Frequency Voltage Regulation Constant Current Energy Saving Device Technical Field

[0001] This invention relates to the field of power electronics technology, and in particular to an IGBT fixed-frequency voltage regulation constant current energy-saving device. Background Technology

[0002] The IGBT fixed-frequency voltage-regulating constant-current energy-saving system is a power regulation system with IGBT power devices as the core and a fixed-frequency voltage-regulating control strategy. It achieves constant output current through precise power regulation. Relying on the characteristics of low conduction and low switching loss of IGBT, it reduces reactive power loss in power conversion and transmission, improves overall power utilization efficiency, and ensures power supply stability. It is suitable for various industrial and power application scenarios that require constant current power supply.

[0003] Existing IGBT voltage regulation constant current devices mostly adopt frequency conversion control or constant current schemes with fixed voltage regulation range. For example, frequency conversion schemes have the disadvantages of large fluctuations in switching losses with frequency changes and strong electromagnetic interference; while fixed frequency schemes with fixed voltage regulation ranges have the disadvantages of high energy consumption due to redundant voltage regulation under light load and poor constant current accuracy due to untimely current compensation under heavy load. At the same time, the dead time of traditional drive modules is fixed and cannot adapt to the dynamic changes of load current, which can easily generate switching losses or commutation spikes, affecting energy saving effect and device stability. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides the following technical solution: an IGBT fixed-frequency voltage-regulating constant-current energy-saving device, comprising: a power supply module, an IGBT power module, a current sampling module, a drive module, a control module, a motor, and a voltage acquisition module, wherein the power supply module receives a drive signal and outputs an adjustable voltage to the load, wherein the current sampling module is connected in series between the IGBT power module and the load, and acquires the load current in real time and outputs a current feedback signal, wherein the drive module is used to output a drive signal with dead time to the IGBT power module, wherein the control module is electrically connected to the current sampling module and the drive module respectively, and the control module is configured with a segmented voltage-regulating constant-current algorithm with a fixed switching frequency.

[0005] The above technical solution describes an IGBT fixed-frequency voltage-regulating constant-current energy-saving device, which is comprised of a power supply module, an IGBT power module, a current sampling module, a drive module, a control module, a motor, and a voltage acquisition module. The IGBT power module, as the core execution unit, accurately receives signals from the drive module and adjusts the output voltage to adapt to load demands, achieving efficient energy transfer. The current sampling module is connected in series between the power module and the load, capturing and feeding back the load current in real time, providing data support for closed-loop control. The drive module outputs a drive signal with dead time to prevent IGBT bridge arm shoot-through damage. The control module, relying on a segmented voltage-regulating constant-current algorithm with a fixed switching frequency, coordinates the collaborative work of all modules, significantly reducing energy consumption under load fluctuations and improving the device's operational stability and energy efficiency.

[0006] As a further description of the above technical solution: the drive module is electrically connected to the motor.

[0007] The above technical solution establishes a bidirectional electrical connection between the drive module and the motor. This connection ensures that the drive signal output by the drive module is accurately transmitted to the motor, enabling smooth start-up and operation. Furthermore, it allows the drive module to dynamically adapt to the motor's operating conditions based on feedback from the motor's operating status. This design effectively isolates electromagnetic interference generated during motor operation, preventing interference signals from affecting the drive module's output accuracy. Simultaneously, it ensures that the motor receives appropriate drive power under different loads, reducing start-up shock and operating losses, extending motor lifespan, and improving the overall operational reliability and compatibility of the device.

[0008] As a further description of the above technical solution: the segmented voltage regulation constant current algorithm includes: a preset fixed switching frequency f (f∈[10kHz, 50kHz]) and load current thresholds I1 (light load threshold) and I2 (heavy load threshold), where I1 < I2. When the load current I corresponding to the current feedback signal is ≤ I1, a wide-range voltage regulation mode (voltage adjustment range U1~Umax) and small-step constant current calibration (step size ΔU1∈[0.01V, 0.05V]) are adopted. Voltage regulation is achieved by adjusting the PWM duty cycle, and the duty cycle is dynamically compensated according to the current deviation. When the load current I corresponding to the current feedback signal is ≥ I2, the narrow-range voltage regulation mode (voltage adjustment range U2~Umax) and fast current compensation (compensation step size ΔU2∈[0.05V, 0.1V]) are switched, where U2 > U1. The control unit dynamically adjusts the dead time t (t∈[0.5μs, ...) of the drive module output according to the rate of change of the load current I. [2μs]), when the absolute value of the rate of change of I is ≥5A / ms, decrease the dead time; when the absolute value of the rate of change of I is <5A / ms, increase the dead time.

[0009] The segmented voltage regulation constant current algorithm in the above technical solution is the core of the device's energy saving and precise current control. A fixed switching frequency f of 10kHz-50kHz and light and heavy load current thresholds I1 < I2 are preset to adapt to different load scenarios. Under light load (I≤I1), wide-range voltage regulation and small-step calibration are used. By fine-tuning the PWM duty cycle and dynamic compensation, both voltage regulation flexibility and constant current accuracy are balanced, reducing energy consumption under light load. Under heavy load (I≥I2), narrow-range voltage regulation and fast compensation are switched to quickly respond to load changes and ensure output stability. Simultaneously, the dead time of 0.5μs-2μs is dynamically adjusted according to the current change rate. The dead time is reduced to lower losses when heavy load fluctuations are large, and increased to ensure safety when light loads are stable, achieving a balance between energy saving and safety.

[0010] As a further description of the above technical solution: the fixed switching frequency f is 20kHz, the load current thresholds I1=1A, I2=5A, the voltage regulation range of the wide-range voltage regulation mode is 0~380V, and the voltage regulation range of the narrow-range voltage regulation mode is 100~380V.

[0011] The above technical solution employs a fixed switching frequency of 20kHz. This frequency avoids the motor's operating noise frequency band and reduces IGBT switching losses, achieving a balance between quiet operation and energy efficiency. Current thresholds of I1=1A and I2=5A are set to precisely define the light and heavy load ranges. Wide-range voltage regulation (0-380V) adapts to low-current scenarios from no-load to light-load, enabling precise voltage adjustment from zero to meet the low-speed start-up requirements of motors. Narrow-range voltage regulation (100-380V) targets heavy-load conditions, reducing the adjustment range to improve response speed and avoid significant voltage fluctuations. This parameter configuration makes the device compatible with most industrial motor loads, maximizing energy loss reduction under different operating conditions while ensuring operational stability.

[0012] As a further description of the above technical solution: the current sampling module is composed of a shunt resistor and an operational amplifier, with a sampling accuracy of ≤±0.5% and a sampling frequency of 10 times the switching frequency.

[0013] The above technical solution employs a combination architecture of a shunt resistor and an operational amplifier in the current sampling module. The shunt resistor features low power consumption and high stability, while the operational amplifier can accurately amplify weak sampling signals. Together, they achieve high-precision sampling of ≤±0.5%, providing accurate data support for constant current control and avoiding control deviations and increased energy consumption caused by sampling errors. The sampling frequency is set to 10 times the switching frequency, enabling real-time capture of instantaneous current changes and timely feedback to the control module. This ensures the control algorithm responds quickly to load current fluctuations, effectively suppresses current ripple, improves the constant current accuracy of the device, and reduces power loss due to sampling lag, ensuring efficient device operation.

[0014] As a further description of the above technical solution: the control unit is an STM32 series microcontroller or DSP chip, and the segmented voltage regulation constant current algorithm is embedded in the control unit through firmware.

[0015] The above technical solution utilizes an STM32 series microcontroller or DSP chip in the control unit. Both possess high-performance computing capabilities, rich peripheral interfaces, and strong anti-interference capabilities, enabling rapid processing of current and voltage feedback signals and precise execution of the segmented voltage regulation constant current algorithm. The algorithm is embedded in the control unit via firmware, preventing software lag or data loss and ensuring the stability and real-time performance of the algorithm. This design not only meets the complex control logic requirements of the device but also facilitates future firmware upgrades and algorithm optimization to adapt to different load scenarios. Furthermore, the chip's low-power characteristics further reduce the device's own energy consumption, improving overall energy efficiency and making it widely applicable in fields such as industrial automation and new energy.

[0016] As a further description of the above technical solution: the IGBT power module adopts an IGBT half-bridge or full-bridge topology, and the driving module is an optocoupler-isolated driving chip.

[0017] The above technical solution employs a half-bridge or full-bridge topology for the IGBT power module. The half-bridge topology is suitable for small to medium power loads, while the full-bridge topology can output higher power to meet the power requirements of different scenarios. A well-designed topology reduces IGBT switching stress, lowers switching losses, and extends module lifespan. The drive module uses an optocoupler-isolated drive chip, providing strong electrical isolation. This effectively isolates the high-voltage power circuit from the low-voltage control circuit, preventing high-voltage interference from damaging the control module. It also improves the accuracy of drive signal transmission, ensuring precise IGBT module turn-on and turn-off. The two work together to enhance the device's anti-interference capability and operational safety, providing reliable hardware support for energy-saving current control.

[0018] As a further description of the above technical solution: the voltage sampling module is used to collect the output voltage of the IGBT power module and feed it back to the control module to form a voltage-current dual closed-loop control.

[0019] The above technical solution involves a voltage sampling module that accurately acquires the output voltage of the IGBT power module and transmits the voltage feedback signal to the control module. This, together with the feedback signal from the current sampling module, forms a voltage-current dual closed-loop control. The voltage loop stabilizes the output voltage in real time, preventing voltage fluctuations from affecting load operation, while the current loop precisely controls the load current, ensuring a constant current. The synergistic effect of the dual closed loops significantly improves the device's control accuracy and anti-interference capability, effectively suppressing voltage and current deviations caused by load changes and reducing energy loss due to parameter fluctuations. Simultaneously, the dual closed-loop design enables the device to respond quickly to sudden load changes, maintaining stable output, improving operational reliability, and further enhancing energy-saving effects.

[0020] The present invention has the following beneficial effects: In the present invention, by configuring a segmented voltage regulation constant current algorithm with a fixed switching frequency in the power supply module, IGBT power module, current sampling module, drive module, control module, motor, voltage acquisition module and control unit, the dead time of the drive module is not fixed, adapting to the dynamic changes of the load current, and without affecting the energy saving effect and device stability. It solves the problem in the prior art that the dead time of the drive module is fixed, which cannot adapt to the dynamic changes of the load current, and is prone to switching losses or commutation spikes, affecting the energy saving effect and device stability.

[0021] In this invention, by dynamically adjusting the dead time, the switching loss of IGBTs is reduced by 15% to 20%, and the overall energy consumption of the load is reduced by 8% to 12%.

[0022] In this invention, electromagnetic interference fluctuations are avoided by fixing the switching frequency, making it suitable for scenarios with high electromagnetic compatibility requirements, such as motors. Attached Figure Description

[0023] Figure 1 is a flowchart of the present invention. Detailed Implementation

[0024] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0025] Referring to Figure 1, one embodiment of the present invention provides an IGBT fixed-frequency voltage-regulating constant-current energy-saving device, comprising: a power supply module, an IGBT power module, a current sampling module, a drive module, a control module, a motor, and a voltage acquisition module. The power supply module receives drive signals and outputs adjustable voltage to the load. The current sampling module is connected in series between the IGBT power module and the load, acquiring the load current in real time and outputting a current feedback signal. The drive module outputs a drive signal with dead time to the IGBT power module. The control module is electrically connected to the current sampling module and the drive module, respectively. The control module is configured with a segmented voltage-regulating constant-current algorithm with a fixed switching frequency.

[0026] In the above embodiment, the hardware architecture of this device includes: the IGBT power module can be selected from the IGBT4 series FF450R12ME4; the shunt resistor of the current sampling module is an alloy resistor RX24 - 1W - 0.01Ω; the operational amplifier is LM358; the driver module is a TLP250 optocoupler isolation driver chip; the control module is an STM32F103 microcontroller; and the voltage sampling module consists of voltage divider resistors + ADS1115 analog-to-digital converter chip.

[0027] Referring to Figure 1, the drive module is electrically connected to the motor.

[0028] Referring to Figure 1, the segmented voltage regulation constant current algorithm includes: a preset fixed switching frequency f (f∈[10kHz, 50kHz]) and a load current threshold, where I1 is the light load threshold and I2 is the heavy load threshold, where I1 < I2. When the load current I corresponding to the current feedback signal is ≤ I1, a wide-range voltage regulation mode (voltage adjustment range U1~Umax) and small-step constant current calibration (step size ΔU1∈[0.01V, 0.05V]) are adopted, and voltage regulation is achieved by adjusting the PWM duty cycle. At the same time, the duty cycle is dynamically compensated according to the current deviation. When the load current I corresponding to the current feedback signal is ≥ I2, the algorithm switches to a narrow-range voltage regulation mode (voltage adjustment range U2~Umax) and fast current compensation (compensation step size ΔU2∈[0.05V, 0.1V]), where U2 > U1. The control unit dynamically adjusts the dead time t (t∈[0.5μs, ..., ...) of the drive module output according to the rate of change of the load current I. [2μs]), when the absolute value of the rate of change of I is ≥5A / ms, decrease the dead time; when the absolute value of the rate of change of I is <5A / ms, increase the dead time.

[0029] Referring to Figure 1, the fixed switching frequency f is 20kHz, the load current thresholds I1=1A, I2=5A, the voltage regulation range of the wide-range voltage regulation mode is 0~380V, and the voltage regulation range of the narrow-range voltage regulation mode is 100~380V.

[0030] Referring to Figure 1, the current sampling module is composed of a shunt resistor and an operational amplifier, with a sampling accuracy of ≤±0.5% and a sampling frequency of 10 times the switching frequency.

[0031] Referring to Figure 1, the control unit is an STM32 series microcontroller or DSP chip, and the segmented voltage regulation constant current algorithm is embedded in the control unit through firmware.

[0032] Referring to Figure 1, the IGBT power module adopts an IGBT half-bridge or full-bridge topology, and the driving module is an optocoupler-isolated driving chip.

[0033] Referring to Figure 1, the voltage sampling module is used to collect the output voltage of the IGBT power module and feed it back to the control module to form a voltage-current dual closed-loop control.

[0034] The core control flow of the above embodiment is as follows: 1. The control unit initializes a fixed switching frequency f = 20kHz, preset I1 = 1A, I2 = 5A, wide-range voltage regulation U1 = 0V~380V, narrow-range voltage regulation U2 = 100V~380V, and initial dead time t = 1μs; 2. The current sampling module collects the load current I in real time and feeds it back to the control unit; 3. The control unit judges the magnitude of I: if I≤1A (light load), the control unit outputs a wide-range PWM signal, adjusting the duty cycle in small steps of ΔU1 = 0.03V to adapt the output voltage to the load within the range of 0~380V, and at the same time compensates the duty cycle according to the current deviation to ensure current stability; if I≥5A (heavy load), it switches to a narrow-range PWM signal, adjusting the duty cycle in small steps of ΔU2 = 0.03V to ensure that the output voltage adapts to the load within the range of 0~380V. At the same time, it compensates the duty cycle according to the current deviation to ensure current stability; if I≥5A (heavy load), it switches to a narrow-range PWM signal, adjusting the duty cycle in small steps of ΔU2 = 0.03V to ensure that the output voltage adapts to the load within the range of 0~380V. 4. The duty cycle is adjusted in a fast step size of 0.08V to avoid frequent voltage fluctuations and accelerate current compensation. 5. The control unit calculates the load current change rate dI / dt in real time: if |dI / dt|≥5A / ms: the current changes rapidly, such as when a motor starts, the dead time is reduced to 0.5μs to reduce commutation spikes; if |dI / dt|<5A / ms: (current is stable), the dead time is increased to 1.5μs to reduce switching losses. 6. The voltage sampling module collects the output voltage and forms a dual closed-loop control with the current feedback to further improve the accuracy of voltage regulation and constant current.

[0035] The above embodiments are merely illustrative of the technical solutions of the present invention and are not intended to limit it. Anyone skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An IGBT fixed-frequency voltage-regulating constant-current energy-saving device, characterized in that, include: The system comprises a power supply module, an IGBT power module, a current sampling module, a drive module, a control module, a motor, and a voltage acquisition module. The motor receives drive signals and outputs adjustable voltage to the load. The current sampling module is connected in series between the IGBT power module and the load, acquiring the load current in real time and outputting a current feedback signal. The drive module outputs a drive signal with dead time to the IGBT power module. The control module is electrically connected to the current sampling module and the drive module, respectively. The control module is configured with a segmented voltage-current regulation algorithm with a fixed switching frequency.

2. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 1, characterized in that: The drive module is electrically connected to the motor.

3. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 1, characterized in that: The segmented voltage regulation constant current algorithm includes: a preset fixed switching frequency f (f∈[10kHz, 50kHz]) and a load current threshold, where I1 is the light load threshold and I2 is the heavy load threshold, and I1 < I2; when the load current I corresponding to the current feedback signal is ≤ I1, a wide-range voltage regulation mode (voltage adjustment range U1~Umax) and small-step constant current calibration (step size ΔU1∈[0.01V, 0.05V]) are adopted, and voltage regulation is achieved by adjusting the PWM duty cycle, while the duty cycle is dynamically compensated according to the current deviation; when the load current I corresponding to the current feedback signal is ≥ I2, the algorithm switches to a narrow-range voltage regulation mode (voltage adjustment range U2~Umax) and fast current compensation (compensation step size ΔU2∈[0.05V, 0.1V]), where U2 > U1; the control unit dynamically adjusts the dead time t (t∈[0.5μs, ..., ...) of the drive module output according to the rate of change of the load current I. [2μs]), when the absolute value of the rate of change of I is ≥5A / ms, decrease the dead time; when the absolute value of the rate of change of I is <5A / ms, increase the dead time.

4. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 3, characterized in that: The fixed switching frequency f is 20kHz, the load current thresholds I1=1A, I2=5A, the voltage regulation range of the wide-range voltage regulation mode is 0~380V, and the voltage regulation range of the narrow-range voltage regulation mode is 100~380V.

5. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 4, characterized in that: The current sampling module is composed of a shunt resistor and an operational amplifier, with a sampling accuracy of ≤±0.5% and a sampling frequency of 10 times the switching frequency.

6. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 4, characterized in that: The control unit is an STM32 series microcontroller or DSP chip, and the segmented voltage regulation constant current algorithm is embedded in the control unit through firmware.

7. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 4, characterized in that: The IGBT power module adopts an IGBT half-bridge or full-bridge topology, and the driving module is an optocoupler-isolated driving chip.

8. The IGBT fixed-frequency voltage-regulating constant-current energy-saving device according to claim 4, characterized in that: The voltage sampling module is used to collect the output voltage of the IGBT power module and feed it back to the control module to form a voltage-current dual closed-loop control.

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