阅读说明：本技术 主动式备用电源的风扇刹车电路 (Fan brake circuit of active standby power supply ) 是由 黄柏胜 黄伟财 周初宪 于 2020-06-03 设计创作，主要内容包括：一种主动式备用电源的风扇刹车电路,包括一保护电路、一马达驱动单元、一马达、一风扇控制器及至少一旁通路径单元,该保护电路接收一输入电源,该马达驱动单元电性连接在该保护电路与该马达之间,用以输出一驱动信号至该马达,该风扇控制器电性连接该马达驱动单元与该保护电路,用以输出一控制信号至该马达驱动单元,该至少一旁通路径单元电性连接在该输入电源与该马达驱动单元之间,用以供该输入电源通过且传送至该马达驱动单元,当该保护电路中断该输入电源传送至该马达时,该马达驱动单元根据该旁通路径单元传送的该输入电源以输出该驱动信号至该马达,使该马达形成一短路回路而刹车。(A fan brake circuit of active standby power supply comprises a protection circuit, a motor driving unit, a motor, a fan controller and at least one bypass path unit, wherein the protection circuit receives an input power supply, the motor driving unit is electrically connected between the protection circuit and the motor and used for outputting a driving signal to the motor, the fan controller is electrically connected with the motor driving unit and the protection circuit and used for outputting a control signal to the motor driving unit, the at least one bypass path unit is electrically connected between the input power supply and the motor driving unit and used for allowing the input power supply to pass through and transmitting the input power supply to the motor driving unit, when the protection circuit interrupts the input power supply from transmitting to the motor, the motor driving unit outputs the driving signal to the motor according to the input power supply transmitted by the bypass path unit, so that the motor forms a short circuit loop to brake.)

1. A fan brake circuit of active standby power supply is characterized by comprising:

a protection circuit, receiving an input power;

a motor electrically connected to the protection circuit;

a motor driving unit electrically connected between the protection circuit and the motor for outputting a driving signal to the motor;

a fan controller electrically connected to the motor driving unit and the protection circuit for outputting a control signal to the motor driving unit;

at least one bypass path unit electrically connected between the input power supply and the motor driving unit for the input power supply to pass through and transmit to the motor driving unit; and

when the input power supply is interrupted by the protection circuit and transmitted to the motor, the motor driving unit outputs the driving signal to the motor according to the input power supply transmitted by the bypass path unit, so that the motor forms a short circuit loop to brake.

2. The active back-up fan brake circuit of claim 1, wherein the protection circuit comprises a protection circuit breaker, a first diode and a second diode, one end of the protection circuit breaker is connected to the input power source, the other end of the protection circuit breaker is electrically connected to one end of the first diode and one end of the second diode, the other end of the first diode is electrically connected to the motor driving unit, and the fan controller is electrically connected to the other end of the second diode and the motor driving unit, respectively.

3. The active fan brake circuit of claim 2, wherein the first diode has an anode terminal and a cathode terminal, the other terminal of the protection circuit breaker is electrically connected to the anode terminal of the first diode, and the cathode terminal of the first diode is electrically connected to the motor driving unit.

4. The active fan brake circuit of claim 2, wherein the second diode has an anode terminal and a cathode terminal, the anode terminal of the second diode is electrically connected to the other terminal of the protection circuit breaker and the first diode, and the cathode terminal of the second diode is electrically connected to the fan controller.

5. The active standby power fan brake circuit of claim 2, wherein the protection circuit breaker is a gas circuit breaker or a fuse.

6. The active standby power fan brake circuit of claim 2, wherein the fan controller is a microprocessor controller, a central processing unit or a digital signal processor.

7. The active fan brake circuit of claim 1, wherein the bypass path unit comprises a bypass breaker and a bypass diode, the bypass diode having an anode terminal and a cathode terminal, the bypass breaker electrically connecting the input power source and the anode terminal of the bypass diode, respectively, and the cathode terminal of the bypass diode electrically connecting the motor driving unit.

8. The active standby power fan brake circuit of claim 7, wherein the bypass breaker is a gas breaker or a fuse.

Technical Field

The invention relates to the field of fan control, in particular to a fan brake circuit of an active standby power supply.

Background

The existing fan brake mechanism mainly controls an electronic switch (MOSFET) of a fan driving unit through a digital signal of a control switch unit, or realizes an equivalent switch function by matching discrete resistors or capacitors with a switch element, controls the on-off of the electronic switch (MOSFET) for driving the front end of a motor through the two modes, and achieves the brake function by singly switching on one of an upper bridge electronic switch (MOSFET) or a lower bridge electronic switch (MOSFET) of the motor driving unit to realize the short-circuit circulation of a motor coil.

Referring to fig. 1, a block diagram of a current fan braking circuit is shown, when a control switch unit fails or an electronic switch (MOSFET) of a fan driving unit fails and is shorted, a frontmost circuit breaker is turned off in a protection manner, so that the entire fan is powered off, and at this time, the active electronic braking function cannot work because the power is not supplied.

Continuing above, in order to solve the above problems, the back electromotive force generated after the fan blade is blown by the return air is used to generate electricity, and the generated electricity is transmitted to the electronic brake to perform braking.

Therefore, how to solve the above problems and disadvantages is a direction in which the present inventors and related manufacturers engaged in the industry are keenly interested in studying and improving.

Disclosure of Invention

To solve the above problems, an object of the present invention is to provide an active stand-by fan brake circuit using an additional independent line as a stand-by power supply.

Another objective of the present invention is to provide a fan braking circuit of an active standby power supply capable of reducing reverse return loss.

To achieve the above objective, the present invention provides an active fan brake circuit of a standby power supply, which includes a protection circuit for receiving an input power supply; a motor driving unit electrically connected between the protection circuit and the motor for outputting a driving signal to the motor; a fan controller electrically connected to the motor driving unit and the protection circuit for outputting a control signal to the motor driving unit; at least one bypass path unit electrically connected between the input power supply and the motor driving unit for the input power supply to pass through and transmit to the motor driving unit; when the input power supply is interrupted by the protection circuit and transmitted to the motor, the motor driving unit outputs the driving signal to the motor according to the input power supply transmitted by the bypass path unit, so that the motor forms a short circuit loop to brake.

Through the structure, in a general state, the power for supplying to the motor driving unit can be supplied through either or both of the protection circuit and the bypass path unit, and when the protection circuit is disconnected due to any factor, the bypass path unit supplies the power to the fan controller so as to achieve the purpose of effective braking.

Drawings

FIG. 1 is a block diagram of a conventional fan brake circuit;

FIG. 2 is a block diagram of a fan braking circuit according to the present invention;

FIG. 3 is a schematic diagram of an actual circuit of the present invention.

Description of reference numerals: vcc-input power; 2-a protection circuit; 21-a protective circuit breaker; 22-a first diode; 23-a second diode; 3-a bypass path unit; 31-a bypass breaker; 32-bypass diode; 4-a fan controller; 41-output pin; 5-a motor drive unit; 51-motor drive; 6-a motor; q1, Q2, Q3-bridge arm transistors; 61-coil.

Detailed Description

The above objects, together with the structural and functional features thereof, are accomplished by the preferred embodiments according to the accompanying drawings.

Referring to fig. 2 and fig. 3, which are block diagrams of the fan brake circuit of the present invention and actual circuit diagrams of the present invention, the fan brake circuit of the active standby power supply of the present invention includes a protection circuit 2, a motor 6, a motor driving unit 5, a fan controller 4 and at least one bypass unit 3, the protection circuit 2 is connected to an input power Vcc (e.g. 12 volts), in this embodiment, the input power Vcc is provided to a power supply, the protection circuit 2 includes a protection circuit breaker 21, a first diode 22 and a second diode 23, the protection circuit breaker is illustrated as a fuse in this embodiment, and is used for tripping to protect circuit breaking during overload, one end of the protection circuit breaker 21 is connected to the input power Vcc, and the other end of the protection circuit breaker 21 is electrically connected to one end of the first diode 22 and one end of the second diode 23, the other end of the first diode 22 is electrically connected to the motor driving unit 5, and the fan controller 4 is electrically connected to the other end of the second diode 23 and the motor driving unit 5, respectively.

The first diode 22 has an anode end and a cathode end, the other end of the protection circuit breaker 21 is electrically connected to the anode end of the first diode 22, the cathode end of the first diode 22 is electrically connected to the motor driving unit 5, the second diode 23 has an anode end and a cathode end, the anode end of the second diode 23 is electrically connected to the other end of the protection circuit breaker 21 and the first diode 22, and the cathode end of the second diode 23 is electrically connected to the fan controller 4. The motor 6 is electrically connected to the motor driving unit 5, and in the embodiment, the motor 6 is a three-phase motor, but the invention is not limited thereto, and in the implementation, the motor 6 may also be a single-phase motor, and the number and the circuit of the motor 6 and the motor driving unit 5 may be changed adaptively. The motor 6 includes a plurality of bridge arm transistors Q1, Q2, Q3 and a motor coil 61, the bridge arm transistors Q1, Q2 and Q3 are connected to the motor driving unit 5 and the motor coil 61, the bridge arm transistors Q1, Q2 and Q3 include a P-MOS transistor and an N-MOS transistor for use as switches of the driving motor 6, in the embodiment, the upper bridge switch is an N-MOS transistor and a lower bridge switch is a P-MOS transistor, but not limited thereto.

The motor driving unit 5 is electrically connected between the protection circuit 2 and the motor 6, the motor driving unit 5 outputs a driving signal to the motor 6 according to the fan controller 4 to drive the motor 6 to operate, in the embodiment, the motor driving unit 5 includes three sets of motor drivers 51 electrically connected to a plurality of corresponding bridge arm transistors Q1, Q2, and Q3, and each set of motor drivers 51 is composed of a transistor and a plurality of resistor elements. The fan controller 4 is a micro-processing controller (MCU) in this embodiment, the fan controller 4 is electrically connected to the motor driving unit 5 and the protection circuit 2, the fan controller 4 has a plurality of output pins 41, the plurality of output pins 41 are electrically connected to the input terminals of the three sets of motor drivers 51 for outputting the control signal (such as PWM signal) to the motor driving unit 5, wherein a power pin of the fan controller 4 is electrically connected to the cathode terminal of the second diode 23. In a possible embodiment, the fan controller 4 may be a Central Processing Unit (CPU) or a Digital Signal Processor (DSP).

The at least one bypass path unit 3 is electrically connected between the input power source 1 and the motor driving unit 5, and is used for the input power source Vcc to pass through and transmit to the motor driving unit 5, so that the bypass path unit 3 can be used as a standby power source for the motor driving unit 5 to drive the upper bridge switches Q1, Q2, and Q3 to be turned on (or turned on by the lower bridge switches). The bypass path unit 3 includes a bypass breaker 31 and a bypass diode 32, the bypass breaker 31 is used for tripping for circuit breaking protection or overcurrent circuit breaking protection when overload occurs, the bypass breaker 31 is connected with the input power source 1, the anode side of the bypass diode 32 is electrically connected with the bypass breaker 31, and the cathode side is connected with the motor driving unit 5.

In this embodiment, the protection breaker 21 and the bypass breaker 31 are not limited to the fuse, and the equivalent elements for preventing the current from being too large or overloaded are the breakers of the present invention, for example, the protection breaker 21 and the bypass breaker 31 are gas breakers, and the first diode 22, the second diode 23 and the bypass diode 32 are used as the rectifying and dividing lines. In an alternative embodiment, the bypass path unit 3 may be a plurality of bypass path units 3 electrically connected between the input power source 1 and the motor driving unit 5.

When the fan motor 6 is in normal operation, the input power source 1 provides a large current required by the motor driving unit 5 to operate through the path of the protection circuit breaker 21 and the first diode 22 of the protection circuit 2, and the path of the protection circuit breaker 21, the first diode 22 and the fan controller 4 provides a small current used by the control signal when the motor driving unit 5 operates, so as to achieve the operation of controlling the rotation speed of the motor 6 and braking.

When the motor 6 is in an abnormal state, the abnormal large current causes the protective circuit breaker 21 of the protective circuit 2 to trip or fuse, so that the protective circuit 2 is disconnected (interrupted) and the motor 6 has no power input, at the moment, the fan blade still rotates due to inertia and cannot be stopped immediately, meanwhile, the bypass path unit 3 provides an input power Vcc to the motor driving unit 5, so that the pin G1 of the transistors (upper bridge switch N-MOS) in the bridge arm transistors Q1, Q2 and Q3 is at a high potential and is turned on (conducted), and all the U phase, the V phase and the W phase of the motor 6 form a short-circuit cycle (short-circuit loop) relative to the terrain to achieve the braking effect.

That is, in a normal state, if the fan controller 4 performs a braking operation, the input power Vcc may be provided by either or both of the protection circuit 2 and the bypass path unit 3, so that the upper and lower switches of the bridge arm transistors Q1, Q2, and Q3 operate together to achieve a better braking effect, and when an abnormality occurs, the bypass path unit 3 provides the input power Vcc to turn on the upper or lower switch of the bridge arm transistors Q1, Q2, and Q3 to perform a braking operation, so as to ensure that the braking operation of the fan can be performed in any state.

In addition, the bypass path unit 3 is composed of only a few elements, so that the occupied space is very small, the manufacturing difficulty is low, the implementation can be easily realized, and moreover, no large current passes through the bypass path unit, so that the failure condition is few, the reliability is high, the brake function is ensured not to fail, and the reverse backflow loss is further reduced.

In summary, the present invention has the following advantages:

1. ensuring the normal braking function:

2. the number of elements is small, and the manufacturing and the implementation are easy;

3. reducing reverse return loss.

The present invention has been described in detail, and the above description is only a preferred embodiment of the present invention, but should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should also be covered by the patent of the present invention.