Control power quick power-down system for regulating and controlling servo driver

Abstract

The invention relates to the technical field of servo driver control, solves the technical problem that the operation efficiency of a servo system is affected due to long power-down time of control power in a main loop bus power taking scheme of a traditional switching power supply, and particularly relates to a control power quick power-down system for regulating and controlling a servo driver. The system comprises a power input module, a main loop rectifying and filtering module, a main loop rectifying and filtering module, a main loop rectifying and filtering module, a main loop rectifying and filtering module, a main loop rectifying and filtering module and an auxiliary loop rectifying and filtering module, an input detection module used for controlling the switching power supply module to stop working rapidly according to the power failure state of the power supply input module is additionally arranged between the power supply input module and the switching power supply module. When the input is powered off, the control power supply can be quickly cut off without waiting for the electric energy of the main loop bus to be exhausted. The circuit not only greatly shortens the restart time of the equipment, improves the efficiency of the equipment and improves the production benefit, but also has the characteristics of simple circuit, high stability and low cost.

Description

Technical Field

[0001] The invention relates to the technical field of servo drive control, and in particular to a control electric fast power-off system for regulating a servo drive. Background Art

[0002] With the rapid expansion of industries such as industrial robots and electronic manufacturing equipment, the application scale of servo systems in China has grown rapidly. For small-volume, high-power density single-board solutions below 750W, more and more applications are being made. The control power supply of the single-board solution needs to be powered from the main circuit bus, and the main circuit bus voltage is converted into a low-voltage power supply through the switching power supply to supply the MCU control circuit, etc. Figure 1 As shown. However, when the servo drive input is powered off, the control power supply must wait until the power of the main circuit bus filter capacitor is basically consumed before the control power supply can stop working. The process of the control power supply completing the power-off may take up to ten seconds. Since the servo drive has a long power-off time, it affects the restart time of the entire device using the drive, reduces the efficiency of the equipment, and reduces production benefits. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a control power fast power-off system for regulating a servo drive, which solves the technical problem that the traditional switching power supply scheme of taking power from the main circuit bus affects the operating efficiency of the servo system due to the long control power-off time.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions: a control power fast power-off system for regulating a servo drive, the system comprising a power input module for connecting to the mains and passing a regulated current, a main circuit rectifier and filter module for rectifying and filtering the regulated current input by the power input module, and the DC power output by the main circuit rectifier and filter module is supplied to a switching power module through a DC bus and then outputs a low-voltage power supply to supply power to an MCU module, and an input detection module for controlling the switching power module to quickly stop working according to the power-off state of the power input module is added between the power input module and the switching power module;

[0005] The input detection module is an input current detection circuit that detects in real time when the power input module is powered off and outputs a low-level signal to the control chip of the switching power module to stop the output and realize rapid power off of the control circuit.

[0006] Furthermore, the power input module is a 200-240V AC±10% power source including power input terminals L1 and L2.

[0007] Furthermore, the input current detection circuit includes a trigger U2 which is connected to the OE enable terminal through a diode D3 and a current limiting resistor R2 after being connected to the power input L1. A voltage regulator D4, a filter capacitor C4, and a resistor R4 for discharging the power in the filter capacitor C4 when power is off are connected in sequence between the OE enable terminal and the control signal input terminal A of the trigger U2. The Vref end output power supply of the control chip U3 is connected to the capacitor C5 to form a stable power supply and then connected to the VCC power supply pin of the trigger U2. The control signal output terminal Y of the trigger U2 is connected to the control chip of the switching power supply module. The control signal input terminal A of the trigger U2 is connected in parallel with the reference ground GND terminal. The resistor R4 and one end of the capacitor C5 are both grounded. The trigger U2 is a three-state trigger.

[0008] Furthermore, the model of the MCU module is STM32F407, and the MCU module is controlled and connected with the servo driver.

[0009] Furthermore, the low-voltage power supply provided by the switching power supply module to the MCU module is 5V.

[0010] Furthermore, the main circuit rectification and filtering module includes a rectifier bridge U1 connected to the power input terminals L1 and L2. After the power input is rectified by the rectifier bridge U1, it is filtered by the bus capacitor C1 to obtain a DC voltage Vbus for inputting power to the switching power module.

[0011] Furthermore, the switching power supply module is a switching power supply circuit composed of a control chip U3, a transformer T1, diodes D1, D2, a voltage reference chip D5, resistors R1, R5, R6, R7, R8, R9, R10, R11, capacitors C2, C3, C6, C7, C8, an optocoupler U4 and a MOS tube Q1.

[0012] Furthermore, the switching power supply circuit includes a resistor R11 connected to the output end of the main circuit rectifier filter module and then connected to the power pin VCC of the control chip U3. The other end of the resistor R11 is connected to the auxiliary winding T1-2 of the transformer T1 through the capacitor C3. The output end of the auxiliary winding T1-2 is connected to the diode D2 and the resistor R1 in turn with the power pin VCC of the control chip U3 to form a loop power supply. The output end of the control chip U3 is connected to the gate of the MOS tube Q1, and the drain of the MOS tube Q1 is connected to the transformer T1. The input end of 1-1 is connected, and the voltage generated by the secondary side of the transformer T1-1 is rectified and filtered by the diode D1 and the capacitor C2 to form a stable low-voltage power supply VCC1. The low-voltage power supply VCC1 is divided by the resistors R8 and R9 and given to the voltage reference chip D5 and connected to the negative electrode of the optocoupler U4. The capacitor C7 is connected in parallel between the resistor R9 and the voltage reference chip D5. The low-voltage power supply VCC1 is connected to the positive electrode of the optocoupler U4 through the resistor R7, and the collector of the optocoupler U4 is connected to the Vref end of the control chip U3 through the resistor R6.

[0013] Furthermore, the switching power supply circuit includes an RC oscillation circuit that forms a clock required for its operation with the internal circuit of the control chip U3. The RC oscillation circuit is connected to the Vref end of the control chip U3 and then connected to the Vfb end of the control chip U3 through a resistor R5 and a capacitor C8. The RT / CT end of the control chip U3 is connected between the resistor R5 and the capacitor C8, and the Vref end of the control chip U3 is connected to a capacitor C6 connected to a reference ground.

[0014] Furthermore, the Isense terminal of the control chip U3 is connected to a resistor R10 for limiting the amplitude of the primary current, and the resistor R10 is connected to the source of the MOSFET Q1 and is grounded.

[0015] By means of the above technical solution, the present invention provides a control power fast power-off system for regulating a servo drive, which has at least the following beneficial effects:

[0016] 1. The control power fast power-off system proposed by the present invention can quickly cut off the control power supply when the input power is off, without waiting for the main circuit bus power to be exhausted. It not only greatly shortens the restart time of the equipment, improves the efficiency of the equipment, and improves the production benefits, but also has the characteristics of simple circuit, high stability and low cost.

[0017] 2. When the input current detection circuit of the present invention detects that the input power supply is powered off, it can quickly control the switch power supply circuit to stop working, thereby realizing the function of quickly powering off the control circuit of the servo drive.

[0018] 3. Based on the original control power switch power supply scheme of taking power from the main circuit bus, the present invention only needs to connect a small number of simple devices to realize the rapid power-off function of the control power, which has strong practical value and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 This is the principle block diagram of the traditional single-board switching power supply busbar power supply solution;

[0021] Figure 2 This is a principle block diagram of the control system for rapid power-off of the present invention;

[0022] Figure 3 The schematic diagram of the circuit of the fast power-off control system of the present invention is shown in FIG. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0024] To solve the problem that the traditional switching power supply in the main circuit bus power supply solution affects the operating efficiency of the servo system due to the long power-off time of the control power, please refer to Figure 2-Figure 3 , this embodiment proposes a control power fast power-off system for regulating servo drive, which can quickly cut off the control power supply when the input power is off, without waiting for the main circuit bus power to be exhausted. It not only greatly shortens the restart time of the equipment, but also improves the efficiency of the equipment and the production efficiency. The system includes a power input module for connecting to the main power supply and passing the voltage-stabilized current, a main circuit rectifier filter module for rectifying and filtering the voltage-stabilized current input by the power input module, and the DC power output by the main circuit rectifier filter module is supplied to the switching power supply module through the DC bus and then outputs a low-voltage power supply to power the MCU module. An input detection module is added between the power input module and the switching power supply module for controlling the switching power supply module to quickly stop working according to the power-off state of the power input module; the power input module is a 200-240V AC±10% power supply including power input terminals L1 and L2; the model of the MCU module is STM32F407, and the MCU module is controlled and connected with the servo drive; the low-voltage power supply of the switching power supply module to power the MCU module is 5V. Specifically, the regulated current output by the power input module is rectified and filtered by the main circuit rectifier and filter module and then supplied to the switching power module via the DC bus. The switching power module outputs a 5V low-voltage power supply to power the MCU module to control and drive the servo driver to operate. The input detection module detects the on and off state of the power input module in real time. When the power input module is disconnected from the input, the input detection module can quickly cut off the control power supply without waiting for the main circuit bus to be exhausted, thereby realizing the function of rapid power-off of the control power.

[0025] The input detection module is an input current detection circuit for real-time detection of the power input module when the power is off, and outputs a low-level signal to the control chip of the switching power module to stop the output to realize the rapid power off of the control power. The input current detection circuit includes a trigger U2 connected to the OE enable end through a diode D3 and a current limiting resistor R2 after being connected to the power input L1, and a voltage regulator tube D4, a filter capacitor C4, and a resistor R4 for discharging the electric quantity in the filter capacitor C4 when the power is off are connected in sequence between the OE enable end and the control signal input end A of the trigger U2, the Vref end output power supply of the control chip U3 is connected to the capacitor C5 to form a stable power supply and then connected to the VCC power supply pin of the trigger U2, and the control signal output end Y of the trigger U2 is connected to the control chip of the switching power module, the control signal input end A of the trigger U2 is connected in parallel with the reference ground GND end, and one end of the resistor R4 and the capacitor C5 are both grounded, and the trigger U2 is a three-state trigger.

[0026] Specifically, the input power supply L1 is composed of a diode D3 that ensures unidirectional current flow, a current-limiting resistor R2 that limits the current flowing through the voltage-regulating tube D4, a filter capacitor C4 that ensures electrical level stability and filters out interference, and a resistor R4 that discharges the electricity in the filter capacitor C4 when power is off. The resistance value of the current-limiting resistor R2 is selected according to the current passing through the selected voltage-regulating tube D4, and it must be ensured that the voltage-regulating tube D4 will not be damaged by overcurrent. The function of the trigger U2 is to output a high-impedance state when the electrical level on C4 is high, and to output a low state when the electrical level is low. U2 can be a three-state trigger (such as Figure 3 When there is normal power input, the input passes through diode D3, current limiting resistor R2, voltage regulator D4 and forms a stable 5V voltage on filter capacitor C4, which is connected to the OE enable terminal of tri-state trigger U2. The trigger enable low level is effective, so the trigger is not enabled at this time, and the output is high impedance, which does not affect the comp signal of the control chip U3 of the switch power control module connected to the control signal output terminal Y of trigger U2. At this time, the switch power module works normally.

[0027] When the power input terminal is disconnected, since there is no input at the power input terminal L1, the electric energy on the filter capacitor C4 is consumed by the resistor R4 and the voltage regulator D4, and the OE enable terminal of the trigger U2 becomes a low level. At this time, the trigger U2 is enabled and valid. Because the control signal input terminal A of the trigger U2 is connected to the reference ground, the output is a low level, and the control chip U3 of the switching power supply module is forced to be pulled to a low level. At this time, the output duty cycle of the output terminal of the control chip U3 is 0, the switching power supply module stops working, and the low-voltage power supply VCC1 outputs 0V, thereby realizing a rapid power-off of the control power when the input is disconnected.

[0028] The input current detection circuit proposed in this embodiment can quickly control the switch power circuit to stop working when detecting that the input power is off, thereby realizing the function of quickly powering off the control circuit of the servo drive.

[0029] The main circuit rectifier and filter module includes a rectifier bridge U1 connected to the power input terminals L1 and L2. After the power input is rectified by the rectifier bridge U1, it is filtered by the bus capacitor C1 to obtain a DC voltage Vbus for inputting power to the switching power module. The switching power module is a switching power circuit composed of a control chip U3, a transformer T1, diodes D1, D2, a voltage reference chip D5, resistors R1, R5, R6, R7, R8, R9, R10, R11, capacitors C2, C3, C6, C7, C8, an optocoupler U4, and a MOS tube Q1. The model of the control chip U3 is UC2844, and the model of the voltage reference chip D5 is TL431.

[0030] The switching power supply circuit includes a resistor R11 connected to the output end of the main circuit rectifier and filter module and then connected to the power pin VCC of the control chip U3. The other end of the resistor R11 is connected to the auxiliary winding T1-2 of the transformer T1 through the capacitor C3. The output end of the auxiliary winding T1-2 is connected to the diode D2 and the resistor R1 in sequence with the power pin VCC of the control chip U3 to form a loop power supply. The output end of the control chip U3 is connected to the gate of the MOS tube Q1, the drain of the MOS tube Q1 is connected to the input end of the transformer T1-1, and the voltage generated by the secondary side of the transformer T1-1 is rectified and filtered by the diode D1 and the capacitor C2 to form a stable low-voltage power supply VCC1. The low-voltage power supply VCC1 is divided by the resistors R8 and R9 and is given to the voltage reference chip D5 and connected to the negative electrode of the optocoupler U4. The capacitor C7 is connected in parallel between the resistor R9 and the voltage reference chip D5. The low-voltage power supply VCC1 is connected to the positive electrode of the optocoupler U4 through the resistor R7, and the collector of the optocoupler U4 is connected to the Vref end of the control chip U3 through the resistor R6.

[0031] The switching power supply circuit includes an RC oscillator circuit that forms the clock required for its operation with the internal circuit of the control chip U3. The RC oscillator circuit is connected to the Vref end of the control chip U3 and then connected to the Vfb end of the control chip U3 through the resistor R5 and the capacitor C8. The RT / CT end of the control chip U3 is connected between the resistor R5 and the capacitor C8, and the Vref end of the control chip U3 is connected to the capacitor C6 connected to the reference ground. The Isense end of the control chip U3 is connected to the resistor R10 that limits the amplitude of its primary current, and the resistor R10 is connected to the source of the MOS tube Q1 and grounded.

[0032] Specifically, one end of the resistor R11 is connected to the positive bus, and the other end is connected to the power pin Vcc of the control chip U3. When the power is on, the capacitor C3 is charged. When the voltage on the capacitor C3 reaches the start-up voltage of the control chip U3, the control chip U3 starts to work. When the switching power supply module works, the auxiliary winding T1-2 generates a voltage, which is rectified and filtered by the diode D2, the resistor R1 and the capacitor C3 to supply power to the control chip U3. The resistor R5 and the capacitor C8 form an RC oscillation circuit with the internal circuit of the control chip U3 to provide the clock required for the internal operation of the control chip U3. The control chip U3 outputs a PWM signal to control the Mos tube Q1 to turn on and off, and the transformer T1-1 transfers the electric energy from the primary side to the secondary side. The voltage generated by the secondary side of the transformer is rectified and filtered by the diode D1 and the capacitor C2 to form a stable low-voltage power supply VCC1.

[0033] The low-voltage power supply VCC1 is divided by resistors R8 and R9 and then given to the voltage reference chip D5 of model TL431. Compared with the internal reference 2.5V of the voltage reference chip D5, when the voltage of the low-voltage power supply VCC1 is higher than the target value, the voltage divided by resistors R8 and R9 is higher than the internal reference 2.5V of the voltage reference chip D5. At this time, the voltage reference chip D5 is turned on, the optocoupler U4 is turned on, the resistor R7 is the current limiting resistor, and the capacitor C7 is the filter capacitor. After the optocoupler U4 is turned on, the voltage of the Comp pin of the control chip U3 will become lower, and the duty cycle of the PWM output by the control chip U3 will become smaller. After the PWM duty cycle is reduced, the voltage of the output low-voltage power supply VCC1 becomes lower, completing the negative feedback. When the low-voltage power supply VCC1 is lower than the target value, the process is reversed, and the low-voltage power supply VCC1 will increase after negative feedback regulation. Through negative feedback, the stable output of the low-voltage power supply VCC1 is finally achieved. Resistor R10 is a current sampling resistor. When the primary current exceeds the set value, the Isense pin voltage of the control chip U3 exceeds the protection value, and the control chip U3 stops outputting the PWM signal, thereby playing a protective role.

[0034] This embodiment is based on the original control power switch power supply from the main circuit bus power supply scheme. Only a small number of simple devices need to be connected to achieve the fast power-off function of the control power, which has strong practical value and economic benefits.

[0035] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the above embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0036] The above implementation methods have been described in detail. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A control power fast power-off system for regulating a servo drive, the system comprising a power input module for connecting to the mains and passing a regulated current, a main circuit rectifier and filter module for rectifying and filtering the regulated current input by the power input module, and the DC power output by the main circuit rectifier and filter module is supplied to a switching power supply module through a DC bus and then outputs a low-voltage power supply to power an MCU module. It is characterized in that An input detection module is added between the power input module and the switch power module to control the switch power module to quickly stop working according to the power-off state of the power input module; The input detection module is an input current detection circuit that detects in real time when the power input module is powered off and outputs a low-level signal to the control chip of the switching power module to stop the output and realize rapid power off of the control circuit.

2. The control power fast power-off system according to claim 1, It is characterized in that The power input module is a 200-240V AC±10% power supply including power input terminals L1 and L2.

3. The control power fast power-off system according to claim 1, It is characterized in that The input current detection circuit includes a trigger U2 which is connected to the OE enable terminal through a diode D3 and a current limiting resistor R2 after being connected to the power input L1. A voltage regulator D4, a filter capacitor C4, and a resistor R4 for discharging the power in the filter capacitor C4 when power is off are connected in sequence between the OE enable terminal and the control signal input terminal A of the trigger U2. The Vref end output power supply of the control chip U3 is connected to the capacitor C5 to form a stable power supply and then connected to the VCC power supply pin of the trigger U2. The control signal output terminal Y of the trigger U2 is connected to the control chip of the switching power supply module. The control signal input terminal A of the trigger U2 is connected in parallel with the reference ground GND terminal. The resistor R4 and one end of the capacitor C5 are both grounded. The trigger U2 is a three-state trigger.

4. The control power fast power-off system according to claim 1, It is characterized in that The model of the MCU module is STM32F407, and the MCU module is controlled and connected with the servo driver.

5. The control power fast power-off system according to claim 1, It is characterized in that The switching power supply module supplies power to the MCU module with a low voltage power supply of 5V.

6. The control power fast power-off system according to claim 1, It is characterized in that The main circuit rectification and filtering module includes a rectifier bridge U1 connected to the power input terminals L1 and L2. After the power input is rectified by the rectifier bridge U1, it is filtered by the bus capacitor C1 to obtain a DC voltage Vbus for inputting power to the switching power module.

7. The control power fast power-off system according to claim 1, It is characterized in that The switching power supply module is a switching power supply circuit composed of a control chip U3, a transformer T1, diodes D1, D2, a voltage reference chip D5, resistors R1, R5, R6, R7, R8, R9, R10, R11, capacitors C2, C3, C6, C7, C8, an optocoupler U4 and a MOS tube Q1.

8. The control power rapid power-off system according to claim 7, It is characterized in that The switching power supply circuit includes a resistor R11 connected to the output end of the main loop rectifier and filter module and then connected to the power pin VCC of the control chip U3. The other end of the resistor R11 is connected to the auxiliary winding T1-2 of the transformer T1 through the capacitor C3. The output end of the auxiliary winding T1-2 is connected to the diode D2 and the resistor R1 in sequence with the power pin VCC of the control chip U3 to form a loop power supply. The output end of the control chip U3 is connected to the gate of the MOS tube Q1, and the drain of the MOS tube Q1 is connected to the input end of the transformer T1-1. The voltage generated by the secondary side of the transformer T1-1 is rectified and filtered by the diode D1 and the capacitor C2 to form a stable low-voltage power supply VCC1. The low-voltage power supply VCC1 is divided by the resistors R8 and R9 and is given to the voltage reference chip D5 and connected to the negative electrode of the optocoupler U4. The capacitor C7 is connected in parallel between the resistor R9 and the voltage reference chip D5. The low-voltage power supply VCC1 is connected to the positive electrode of the optocoupler U4 through the resistor R7, and the collector of the optocoupler U4 is connected to the Vref end of the control chip U3 through the resistor R6.

9. The control power rapid power-off system according to claim 7 or 8, It is characterized in that The switching power supply circuit includes an RC oscillation circuit that forms a clock required for its operation with the internal circuit of the control chip U3. The RC oscillation circuit is connected to the Vref end of the control chip U3 and then connected to the Vfb end of the control chip U3 through a resistor R5 and a capacitor C8. The RT / CT end of the control chip U3 is connected between the resistor R5 and the capacitor C8, and the Vref end of the control chip U3 is connected to a capacitor C6 connected to a reference ground.

10. The control power fast power-off system according to claim 7 or 8, It is characterized in that The Isense terminal of the control chip U3 is connected to a resistor R10 for limiting the amplitude of the primary current, and the resistor R10 is connected to the source of the MOSFET Q1 and is grounded.

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