A power control device for a driving device, a control method thereof, and a driving device

Abstract

The present invention discloses a power control device for a driving device, its control method, and a driving device. The device includes: a first buffer module configured to perform buffering processing on a first stage during the power-on process of the power supply of the driving device; the first stage is the stage from when the power supply of the driving device is powered on to when the voltage of the bus unit rises to a set voltage threshold; a second buffer module configured to perform buffering processing on a second stage during the power-on process of the power supply of the driving device; the second stage is the stage from when the voltage of the bus unit rises to the set voltage threshold to when the power-on of the power supply of the driving device is completed. With this solution, by setting an inductor and a resistor with a defined resistance value in the main circuit, it is possible to reduce the peak current with little impact on the charging time of driving devices such as servo drivers and frequency converters.

Description

Technical Field

[0001] The present invention belongs to the technical field of driving devices, and particularly relates to a power control device for a driving device, a control method thereof, and a driving device, and more particularly to a power control device for a servo driver, a control method thereof, and a driving device. Background Art

[0002] With the development of the industrial field, devices such as robots and machine tools are increasingly widely used, and driving devices such as servo drivers and frequency converters are also popularized. In driving devices such as servo drivers and frequency converters, there is a power-on buffer circuit. For the power-on buffer circuit, most of the related solutions pre-charge through a pre-charge resistor, and then short-circuit the pre-charge resistor to enter the normal working state. However, directly short-circuiting the pre-charge resistor without any treatment is often accompanied by a relatively large current spike, which is likely to affect rectifying devices, switching devices, bus capacitors, etc., reducing their service life or even damaging them.

[0003] The above content is only used to assist in understanding the technical solution of the present invention, and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The purpose of the present invention is to provide a power control device for a driving device, a control method thereof, and a driving device, so as to solve the problem that in the power-on buffer circuit of driving devices such as servo drivers and frequency converters, pre-charging is performed through a pre-charge resistor, and then the pre-charge resistor is short-circuited to enter the normal working state, where directly short-circuiting the pre-charge resistor is accompanied by a relatively large current spike, resulting in an excessive current spike when the bus capacitor switches back to the main circuit during pre-charging, and there are safety hazards, and achieve the effect of reducing the spike current by setting an inductor and a resistor with a limited resistance value in the main circuit, with little impact on the charging time of driving devices such as servo drivers and frequency converters.

[0005] In a power control device for a driving device provided by the present invention, the power supply of the driving device includes a rectifying unit, a bus unit, and an inverting unit; the rectifying unit, the bus unit, and the inverting unit are arranged in sequence; the power control device of the driving device includes a power-on buffer unit; the power-on buffer unit is arranged between the rectifying unit and the bus unit; the power-on buffer unit includes a first buffer module and a second buffer module; the first buffer module and the second buffer module are arranged between the rectifying unit and the bus unit; wherein, the first buffer module is configured to perform a buffering process on the first stage in the power-on process of the power supply of the driving device; the first stage is the stage from the power-on of the power supply of the driving device to the voltage of the bus unit rising to a set voltage threshold; the second buffer module is configured to perform a buffering process on the second stage in the power-on process of the power supply of the driving device; the second stage is the stage from the voltage of the bus unit rising to the set voltage threshold to the completion of the power-on of the power supply of the driving device.

[0006] In some embodiments, the first buffer module includes a first buffer switch module, a first resistor module, and a thyristor module; the second buffer module includes a second resistor module, an inductor module, and a second buffer switch module; wherein, the first buffer switch module, the first resistor module, the second resistor module, and the inductor module are connected in series between the first connection end of the rectifying unit and the first connection end of the bus unit; the thyristor module is arranged between the first connection end of the rectifying unit and the common end between the first resistor module and the second resistor module; the second buffer switch module is arranged between the common end between the first resistor module and the second resistor module and the first connection end of the bus unit.

[0007] In some embodiments, the power control device of the driving device further includes a braking unit; the braking unit is located between the power-on buffer unit and the bus unit, and is arranged between the first connection end and the second connection end of the bus unit; wherein, the braking unit is configured to release the energy of the bus unit to reduce the bus voltage of the bus unit when the bus voltage of the bus unit reaches a set maximum voltage threshold.

[0008] In some embodiments, the braking unit includes a braking switch module; when the bus voltage of the bus unit reaches the set maximum voltage threshold, the braking switch module cooperates with the second buffer switch module to release the energy of the bus unit through the second resistor module.

[0009] In some embodiments, the power control device of the driving device further includes: a PFC unit; the PFC unit is configured to improve the power factor of the power control device of the driving device.

[0010] In some embodiments, the power control device of the driving device further includes: a PFC switch module, a first diode module, and a second diode module; wherein, the inductor module, the PFC switch module, the first diode module, and the second diode module form a PFC circuit; the inductor module is connected to the anode of the second diode module; the cathode of the second diode module is connected to the first connection end of the bus unit; the anode of the first diode module is connected to the first connection end of the bus unit; the cathode of the first diode module is connected to the second connection end of the PFC switch module; the first connection end of the PFC switch module is connected to the thyristor module; the first connection end of the second buffer switch module is connected to the common end of the first resistor module and the second resistor module; the second connection end of the second buffer module is connected to the anode of the second diode module; the first connection end of the braking switch module is connected to the anode of the second diode module; the second connection end of the braking switch module is connected to the second connection end of the bus unit.

[0011] Matched with the above device, on the other hand, the present invention provides a driving device, including: the power control device of the driving device described above.

[0012] Matched with the above driving device, on the other hand, the present invention provides a power control method for a driving device, including: when the power control device of the driving device includes a first buffer switch module, a second buffer switch module, a thyristor module, a braking switch module, and a PFC switch module, in the first stage of power-on buffering of the driving device, controlling the first buffer switch module to close, controlling the second buffer switch module to conduct, controlling the thyristor module to turn off, controlling the braking switch module to turn off, and controlling the PFC switch module to turn off; in the second stage of power-on buffering of the driving device, controlling the second buffer switch module to turn off, controlling the first buffer switch module to open, and controlling the thyristor module to conduct.

[0013] In some embodiments, it further includes: after the second stage of power-on buffering of the driving device is completed, controlling the PFC switch module to conduct to control the normal operation of the power supply of the driving device.

[0014] In some embodiments, it further includes: when the power supply of the driving device is working normally, if the bus voltage of the bus unit reaches the set maximum voltage threshold, controlling the thyristor module to turn off, controlling the PFC switch module to turn off, controlling the second buffer switch module to turn on, and controlling the braking switch module to turn on, so that the braking switch module, the second resistor module, and the first diode module form a discharge circuit to release the bus voltage of the bus unit.

[0015] Therefore, in the solution of the present invention, by setting an inductor and a resistor with a defined resistance value in the main circuit of driving devices such as servo drivers and frequency converters as a protection module, after the power-on buffer resistor is charged to the switching voltage set by the software, the circuit will be switched to the main circuit, and the impedance of the main circuit is increased through the protection module. Thus, by setting an inductor and a resistor with a defined resistance value in the main circuit, the peak current can be reduced with little impact on the charging time of driving devices such as servo drivers and frequency converters.

[0016] Furthermore, in the solution of the present invention, by setting an inductor and a resistor with a defined resistance value in the main circuit of driving devices such as servo drivers and frequency converters as a protection module; after the power-on buffering is completed, the resistor with a defined resistance value in the protection module is short-circuited, and the inductor in the protection module is used for the PFC circuit and connected to the main circuit, and driving devices such as servo drivers and frequency converters enter the normal working state; after the driving devices such as servo drivers and frequency converters are braked, the resistor with a defined resistance value in the protection module is changed from the short-circuited state to the state of being connected to the main circuit of the driving devices such as servo drivers and frequency converters and used as a braking resistor, and the braking tube uses the switching tube of the PFC circuit. Thus, the introduction of the active PFC circuit is realized, and the power factor can be greatly improved.

[0017] Furthermore, in the solution of the present invention, by introducing the active PFC circuit and combining the PFC circuit, the regenerative braking circuit, and the power-on buffering circuit together, the volume of the driver is reduced and the cost is lowered.

[0018] Other features and advantages of the present invention will be described in the following specification, and some of them will become obvious from the specification or be understood by implementing the present invention.

[0019] The technical solution of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of an embodiment of the power control device of the driving device of the present invention;

[0021] Figure 2Schematic diagram of a structure of an embodiment of a servo driver power control topology circuit in a related solution;

[0022] Figure 3 Schematic diagram of a structure of an embodiment of the servo driver power control topology circuit of the present invention;

[0023] Figure 4 Schematic diagram of the current flow direction in the first stage of the power-on buffer of the servo driver power control topology circuit of the present invention;

[0024] Figure 5 Schematic diagram of the current flow direction in the second stage of the power-on buffer of the servo driver power control topology circuit of the present invention;

[0025] Figure 6 Schematic diagram of the normal working current flow direction of the servo driver power control topology circuit of the present invention;

[0026] Figure 7 Schematic diagram of the regenerative braking current flow direction of the servo driver power control topology circuit of the present invention;

[0027] Figure 8 Table of the conduction conditions of each switching tube in each stage of the servo driver power control topology circuit of the present invention;

[0028] Figure 9 Schematic diagram of the flow of an embodiment of the power control method of the drive device of the present invention. Detailed implementation manners

[0029] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0030] For current spikes, two solutions are adopted in the related solutions: one is to use devices with a larger power rating, which can withstand larger instantaneous spike currents, but this will increase the volume and cost of the device. The other is to increase the switching bus voltage threshold to reduce the spike current, but this method will greatly increase the charging time and is not conducive to the normal use of the device.

[0031] In drive devices such as servo drivers and frequency converters, there are also PFC (power factor correction) circuits and regenerative braking circuits. However, in most servo drivers, frequency converters and other drive devices, each part of the circuit is separated, for example, the power-on buffer circuit, PFC (power factor correction) circuit and regenerative braking circuit are separated.

[0032] In addition, most servo drivers do not incorporate a PFC circuit. Among the small number of drivers with a PFC circuit, most use a single-inductor PFC circuit, i.e., a passive PFC or a non-active PFC. The power factor of this PFC is generally only between 0.7 and 0.8, and the inductor is generally relatively heavy. For the drive circuit of a multi-axis industrial robot, some solutions propose a method that can share the regenerative braking resistor and the power-on buffer resistor, but this method does not incorporate a PFC circuit and does not process current spikes.

[0033] According to an embodiment of the present invention, a power control device for a drive device is provided. Refer to Figure 1 the structural schematic diagram of an embodiment of the device of the present invention as shown. The power control device for the drive device may include: the power supply of the drive device, including: a rectification unit, a bus unit, and an inversion unit. The rectification unit, the bus unit, and the inversion unit are arranged in sequence. The rectification unit is like a rectifier bridge, the bus unit is like a bus capacitor C1, and the inversion unit is like an inverter bridge. The power control device for the drive device, such as a power control circuit, includes: a power-on buffer unit. The power-on buffer unit is arranged between the rectification unit and the bus unit.

[0034] The power-on buffer unit includes: a first buffer module and a second buffer module. The first buffer module and the second buffer module are arranged between the rectification unit and the bus unit. Specifically, the first buffer module and the second buffer module are arranged in sequence in the main circuit between the rectification unit and the bus unit, and are configured to perform staged buffer processing on the power-on process of the power supply of the drive device.

[0035] Among them, the first buffer module is configured to perform caching processing on the first stage in the power-on process of the power supply of the drive device. The first stage is the stage from the power-on of the power supply of the drive device to the voltage of the bus unit rising to a set voltage threshold.

[0036] The second buffer module is configured to perform caching processing on the second stage in the power-on process of the power supply of the drive device. The second stage is the stage from the voltage of the bus unit rising to the set voltage threshold to the completion of the power-on of the power supply of the drive device.

[0037] Figure 2 It is the structural schematic diagram of an embodiment of the power control topology circuit for the servo driver power supply in the related solution. As Figure 2 shown, the power supply circuit of the servo driver includes: a rectifier bridge, a power control circuit, a bus capacitor C1, and an inverter bridge. Among them, the power control circuit includes: a power-on buffer circuit and a braking circuit.

[0038] In Figure 2 In the example shown, the rectifier bridge is composed of diode D1, diode D2, diode D3, diode D4, diode D5, and diode D6. The power-on buffer circuit includes: switch K1, resistor R1, and thyristor D7. The braking circuit includes: resistor R2, switching transistor Q8, and switching transistor Q9. The inverter bridge includes: switching transistors Q2, Q3, Q4, Q5, Q6, and Q7.

[0039] Figure 2 The power control topology circuit of the servo driver shown is composed of two independent circuits, namely: the power-on buffer circuit and the regenerative braking circuit. When power is turned on, switch K1 closes, and it first charges through the power-on buffer resistor (such as resistor R1). After reaching the voltage threshold set by the software, switch K1 opens, and thyristor D7 closes. The current flows through thyristor D7. At this time, due to the small impedance in the loop, a very large current spike will appear instantaneously, which will affect the power components, switching devices, and even external devices. This current spike can generally be adjusted by adjusting the voltage threshold of the loop switching. However, since the power-on buffer resistor is relatively large, as the voltage across the capacitor increases, the current will decrease, and the charging time will be very long. At the same time, the power-on buffer resistor will heat up, which has a greater impact on the life of the buffer resistor and the normal operation of the entire system.

[0040] Therefore, the solution of the present invention designs a power control device for a servo driver, which at least solves the problem of excessive current spikes during power-on buffer switching. The solution of the present invention proposes a power control device for a servo driver. By designing a power control device for a servo driver in the servo driver and controlling the circuit operation through the power control of the drive device, the spike current is reduced without substantially affecting the charging time of the servo driver.

[0041] In some embodiments, the first buffer module includes: a first buffer switch module, a first resistor module, and a thyristor module. The first buffer switch module is, for example, switch K1. The first resistor module is, for example, resistor R1. The thyristor module is, for example, thyristor D7.

[0042] The second buffer module includes: a second resistor module, an inductor module, and a second buffer switch module. The second resistor module is, for example, resistor R2, the inductor module is, for example, inductor L1, and the second buffer switch module is, for example, switching transistor Q9.

[0043] Among them, the first buffer switch module, the first resistor module, the second resistor module, and the inductor module are connected in series between the first connection end of the rectifier unit and the first connection end of the bus unit. The first connection end of the rectifier unit is, for example, the cathode of the rectifier diode.

[0044] The thyristor module is disposed between the first connection end of the rectifying unit and the common end between the first resistor module and the second resistor module.

[0045] The second buffer switch module is disposed between the common end between the first resistor module and the second resistor module and the first connection end of the bus unit.

[0046] Figure 3 It is a schematic structural diagram of an embodiment of the servo driver power control topology circuit of the present invention. As Figure 3 shown, in the solution of the present invention, an inductor L1 and a small-value resistor R2 are connected in the main circuit to absorb current spikes. At the same time, after the charging is completed, the inductor L1 is used as the PFC inductor of the PFC circuit, and the resistor R2 is used as the braking resistor during regenerative braking. In this way, after the power-on buffer is completed, there will be no waste of components being left unused. Since the PFC circuit needs to use a switching transistor, and when the driver is in the regenerative braking state, the PFC circuit can be not working. The PFC switching transistor is the switching transistor Q8. During braking, the current will flow through these two transistors, namely the switching transistor Q8 and the switching transistor Q9. Therefore, these two transistors, the switching transistor Q8 and the switching transistor Q9, can also be used as braking switching transistors.

[0047] In the solution of the present invention, after charging to the switching voltage set by the software through the power-on buffer resistor, the circuit will be switched to the main circuit. At this time, a small-value resistor and an inductor are provided in the main circuit to increase the impedance of the main circuit, thereby greatly reducing the excessive current spike caused by the too low impedance of the main circuit after switching the circuit, solving the problem of the too large current spike generated when the bus capacitor switches back to the main circuit during pre-charging, and at the same time solving the problem of damage or reduced lifespan of devices such as the bus capacitor, rectifying module, and switch due to current spikes. This small-value resistor, since it will be used for regenerative braking later, therefore, its resistance value depends not only on the power-on buffer, but more importantly on regenerative braking. So, for the value of the resistance of this small-value resistor, specifically, it depends on the capacity of the entire system and the usage environment of the system, and is generally 5 - 15 Ω.

[0048] Among them, using the principle that the inductor current cannot change suddenly, after the circuit is switched to the main circuit, the inductor L1 will prevent the current from rising instantaneously, reducing the current spike. At the same time, the resistor R2 will play a certain current-limiting role, making the current spike further reduced, reducing the loop current spike generated when switching the pre-charging loop, and ensuring the service life of related power devices.

[0049] In some embodiments, the power control device of the driving device, such as a power control circuit, further includes: a braking unit. The braking unit is located between the power-on buffer unit and the bus unit, and is disposed between the first connection end and the second connection end of the bus unit.

[0050] Wherein, the braking unit is configured to release the energy of the bus unit when the bus voltage of the bus unit reaches a set maximum voltage threshold, so as to reduce the bus voltage of the bus unit.

[0051] In some embodiments, the braking unit includes: a braking switch module. The braking switch module, such as switch tubes Q8 and Q9.

[0052] When the bus voltage of the bus unit reaches a set maximum voltage threshold, the braking switch module cooperates with the second buffer switch module to release the energy of the bus unit through the second resistor module.

[0053] In Figure 3 In the example shown, a switch tube Q9 is also provided. The switch tube Q9 is mainly used to switch between the power-on buffer and the normal working states, and can cooperate with the switch tube Q8 to achieve this function when the system undergoes regenerative braking. The resistor R2 is used to discharge energy during regenerative braking and to reduce current spikes during power-on buffering.

[0054] In some embodiments, the power control device of the driving device, such as a power control circuit, further includes: a PFC unit, such as a PFC circuit.

[0055] The PFC unit is configured to improve the power factor of the power control device of the driving device.

[0056] The solution of the present invention also introduces an active PFC circuit and combines power-on buffering, regenerative braking, and the PFC circuit. Thus, a power control device of a servo driver provided by the solution of the present invention has PFC and regenerative braking functions while dealing with the spikes generated by power-on buffer switching, and can achieve different functions at different times.

[0057] Among them, introducing an active PFC circuit (the power factor can reach 0.98) can greatly improve the power factor. Specifically, in the solution of the present invention, after the power-on buffering is completed, a small-value resistor is short-circuited, and the inductor is used to connect the PFC circuit to the main circuit, and the driver enters the normal working state. After the driver brakes, the previously short-circuited resistor is connected to the circuit for braking, and the braking tube uses the switch tube of the PFC.

[0058] In some embodiments, the power control device of the driving device, such as a power control circuit, further includes: a PFC switch module, a first diode module, and a second diode module. The PFC switch module, such as switching transistor Q8. The first diode module, such as diode D8, and the second diode module, such as diode D9.

[0059] Among them, the inductor module, the PFC switch module, the first diode module, and the second diode module form a PFC circuit.

[0060] The inductor module is connected to the anode of the second diode module. The cathode of the second diode module is connected to the first connection end of the bus unit. The anode of the first diode module is connected to the first connection end of the bus unit. The cathode of the first diode module is connected to the second connection end of the PFC switch module (such as the emitter of switching transistor Q8). The first connection end of the PFC switch module (such as the collector of switching transistor Q8) is connected to the thyristor module.

[0061] The first connection end of the second buffer switch module (such as the collector of switching transistor Q9) is connected to the common end of the first resistor module and the second resistor module. The second connection end of the second buffer module (such as the emitter of switching transistor Q9) is connected to the anode of the second diode module. The first connection end of the braking switch module (such as the collector of switching transistor Q8) is connected to the anode of the second diode module. The second connection end of the braking switch module (such as the emitter of switching transistor Q8) is connected to the second connection end of the bus unit.

[0062] In Figure 3 the example shown, switching transistor Q1 is also provided. Switching transistor Q1 is a PFC switching transistor and is used to form a PFC circuit. In Figure 3 the example shown, diodes D8 and D9 are also provided. Diode D8 is used to form a PFC circuit and is also used as a component in the loop during regenerative braking. Inductor L1, switching transistor Q1, diode D9, and diode D8 form a PFC circuit. At the same time, inductor L1 is used to reduce current spikes during the power-on buffer switching. The PFC circuit is used to improve the power factor of the system.

[0063] Among them, in combination with Figure 2 and Figure 3 the example shown, in Figure 3In the example shown, the switch K1, resistor R1, resistor R2, inductor L1, and diode D9 are sequentially arranged between the first output terminal of the rectifier bridge and the first end of the bus capacitor (such as capacitor C1). The inductor L1 is connected to the anode of the diode D9. One end of the thyristor D7 is connected to the end of the switch K1 away from the resistor R1. The other end of the thyristor D7 is connected to the end of the resistor R1 away from the switch K1.

[0064] The drain of the switching transistor Q1 is connected to the common terminal of the resistor R1 and the resistor R2. The source of the switching transistor Q1 is connected to the cathode of the diode D8. The anode of the diode D8 is connected to the first end of the bus capacitor C1. The drain of the switching transistor Q9 is connected to the common terminal of the resistor R1 and the resistor R2. The source of the switching transistor Q9 is connected to the anode of the diode D9. The drain of the switching transistor Q8 is connected to the anode of the diode D9. The source of the switching transistor Q8 is connected to the second end of the bus capacitor.

[0065] By adopting the technical solution of the present invention, an inductor and a resistor with a defined resistance value are arranged in the main circuit of driving devices such as servo drivers and frequency converters as a protection module. After the power-on buffer resistor is charged to the switching voltage set by the software, the circuit will be switched to the main circuit, and the impedance of the main circuit is increased through the protection module. Thus, by arranging an inductor and a resistor with a defined resistance value in the main circuit, the peak current can be reduced with little impact on the charging time of driving devices such as servo drivers and frequency converters.

[0066] According to an embodiment of the present invention, there is also provided a driving device corresponding to a power control device of a driving device. The driving device may include: the power control device of the driving device described above.

[0067] Since the processing and functions implemented by the driving device in this embodiment are basically corresponding to the embodiments, principles, and examples of the device, for the details not described in the description of this embodiment, reference may be made to the relevant descriptions in the foregoing embodiments, and no further elaboration will be provided here.

[0068] By adopting the technical solution of the present invention, an inductor and a resistor with a defined resistance value are arranged in the main circuit of driving devices such as servo drivers and frequency converters as a protection module. After the power-on buffer is completed, the resistor with a defined resistance value in the protection module is short-circuited, and the inductor in the protection module is used for the PFC circuit and connected to the main circuit. The servo driver, frequency converter, and other driving devices enter the normal working state. After the servo driver, frequency converter, and other driving devices are braked, the resistor with a defined resistance value in the protection module is changed from the short-circuited state to the state of being connected to the main circuit of the servo driver, frequency converter, and other driving devices and used as a braking resistor, and the braking tube uses the switching transistor of the PFC circuit. Thus, the introduction of the active PFC circuit is realized, and the power factor can be greatly improved.

[0069] According to an embodiment of the present invention, there is also provided a power control method for a driving device corresponding to the driving device, as Figure 9 shown in the flowchart of an embodiment of the method of the present invention. The power control method for the driving device may include: a power control process in the case of power-on buffering, specifically including: step S110 and step S120.

[0070] At step S110, when the power control device of the driving device includes a first buffer switch module, a second buffer switch module, a thyristor module, a braking switch module, and a PFC switch module, in the first stage of power-on buffering of the driving device, control the first buffer switch module to close, control the second buffer switch module to conduct, control the thyristor module to turn off, control the braking switch module to turn off, and control the PFC switch module to turn off.

[0071] At step S120, in the second stage of power-on buffering of the driving device, control the second buffer switch module to turn off, control the first buffer switch module to disconnect, and control the thyristor module to conduct.

[0072] Figure 8 This is a table showing the conduction conditions of each switching tube in each stage of the power control topology circuit of the servo driver of the present invention. In Figure 3 the example shown, the above several components are not used simultaneously at the same time, so they can be multiplexed, which not only saves space, reduces the volume, but also reduces the cost. Its specific working process is as follows (the conduction conditions of each switching tube are as shown in the example of Table 8):

[0073] Figure 4 This is a schematic diagram of the current flow direction in the first stage of power-on buffering of the power control topology circuit of the servo driver of the present invention. When just powered on, the switch K1 (such as a relay) closes, the switching tube Q9 conducts, and the rest of the switching devices do not conduct. Its current flow direction is as Figure 4 shown. After the current is rectified, it passes through the buffer resistor (such as resistor R1), the switching tube Q9, the diode D9, and the bus capacitor C1 to the ground to charge the capacitor. At this time, the magnitude of the current and the charging speed are determined by the resistor R1.

[0074] Figure 5 This is a schematic diagram of the current flow direction in the second stage of power-on buffering of the power control topology circuit of the servo driver of the present invention. When the capacitor voltage rises to the switching threshold set by the software, it starts to switch to the main circuit for charging. At this time, the switching tube Q9 turns off, the switch K1 (such as a relay) disconnects, and the thyristor D7 conducts. Its current flow direction is as Figure 5, after rectification, the current passes through thyristor D7, current-limiting resistor R2, absorption inductor L1, diode D9, and bus capacitor C1 to continue charging the capacitor. During this stage, since the inductor current cannot change suddenly, at the moment of switching, the inductor will provide a large impedance to reduce the current spike. Then the inductor impedance will become smaller, equivalent to a wire. At this time, the charging current is determined by resistor R2. Since the bus capacitor voltage has been charged to a certain value after the first-stage charging process, the voltage across resistor R2 decreases. At this time, a resistor smaller than R1 needs to be selected to shorten the charging time.

[0075] In the solution of the present invention, the power-on buffer is processed in segments, and one of the resistors is used for regenerative braking. In this way, by using two resistors in cooperation, the braking resistor parameters can be changed without affecting the charging time. In the solution of the present invention, although a resistor is added, this resistor is subsequently used for the regenerative braking function and will not cause an increase in cost and volume.

[0076] In some embodiments, the power supply control method of the drive device further includes: the power supply control process under normal working conditions after the power-on buffer is completed, specifically including: after the second stage of the power-on buffer of the power supply of the drive device is completed, controlling the PFC switch module to conduct to control the normal operation of the power supply of the drive device.

[0077] Figure 6 It is a schematic diagram of the normal working current direction of the power supply control topology circuit of the servo driver of the present invention. When the bus capacitor voltage reaches the threshold set by the software, at this time the bus capacitor voltage has basically reached the target value, and switch Q1 conducts to bypass resistor R2 and switch the loop to the main loop. At this time, PFC inductor L1, switch Q8, and boost diode D9 form a PFC circuit to improve the power factor of the circuit.

[0078] In some embodiments, the power supply control method of the drive device further includes: the power supply control process during braking under normal working conditions, specifically including: when the power supply of the drive device is operating normally, if the bus voltage of the bus unit reaches the set maximum voltage threshold, then control the thyristor module to turn off, control the PFC switch module to turn off, control the second buffer switch module to conduct, and control the braking switch module to conduct, so that the braking switch module, the second resistor module, and the first diode module form a discharge loop to release the bus voltage of the bus unit.

[0079] Figure 7Schematic diagram of the regenerative braking current path of the servo drive power control topology circuit of the present invention. During the operation of the drive, motor deceleration or other reasons will cause the bus voltage to rise. If not handled in time and the energy is dissipated, the bus voltage will continue to rise. When it reaches the maximum voltage value that the capacitor can withstand, the capacitor will be damaged. Therefore, when the bus voltage reaches the maximum threshold set by the software, the braking circuit will be activated to dissipate the energy through the braking resistor, thereby reducing the bus voltage. The present invention uses the switching transistor Q8, the switching transistor Q9, the resistor R2 and the diode D8 to form a discharge circuit to discharge the system. The current flow in this process is as Figure 7 , at this stage, the thyristor D7 is turned off, the switching transistor Q1 is turned off, and the switching transistors Q8 and Q9 are turned on. Since the bus voltage is relatively high, that is, the capacitor voltage is high, the diode D9 is reverse cut-off. Since the braking time is relatively short and generally in the form of pulses, for the inductor L1, the current mutation is relatively large, so the impedance presented is relatively large, and the current will pass through the resistor R2 branch instead of the inductor L1 branch. Therefore, the current flow is: through the diode D8, the resistor R2, the switching transistor Q9, the switching transistor Q8 to the ground. After the braking is completed, it returns to the main circuit for operation.

[0080] In the above embodiment, the switching device can be replaced by any device with switching characteristics.

[0081] In the solution of the present invention, the PFC circuit, the regenerative braking circuit and the power-on buffer circuit are also combined together, with reduced volume, simple structure, low cost and strong practicability. Combining the power-on buffer, braking and PFC circuits together reduces the volume, reduces the cost and improves the power factor.

[0082] Specifically, in the solution of the present invention, an active PFC circuit is introduced, and the power-on buffer, PFC and braking circuits are combined into one, which improves the power factor, reduces the volume of the drive, reduces the cost, and solves the problem that the inductors, switching transistors in the PFC circuit and the buffer resistors in the power-on buffer circuit are used singly, resulting in a relatively large overall volume. The solution of the present invention combines the PFC circuit with the power-on buffer circuit and the regenerative braking circuit, which not only stabilizes the bus voltage, but also enables the circuit to reuse components at different time periods, reduces the cost, enhances the reliability of the servo drive, can adjust parameters according to the application occasion, and increases the applicable range.

[0083] Since the processing and functions implemented by the method of this embodiment are basically corresponding to the embodiments, principles and examples of the foregoing driving device, for the parts not detailed in the description of this embodiment, reference can be made to the relevant descriptions in the foregoing embodiments and will not be elaborated here.

[0084] Adopting the technical solution of this embodiment, by introducing an active PFC circuit and combining the PFC circuit, the regenerative braking circuit and the power-on buffer circuit, the volume of the driver is reduced and the cost is lowered.

[0085] In summary, it is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned advantageous ways can be freely combined and superimposed.

[0086] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A power control device for a driving device, characterized in that, The power supply of the drive device includes a rectification unit, a bus unit, and an inversion unit; the rectification unit, the bus unit, and the inversion unit are arranged in sequence; the power supply control device of the drive device includes a power-on buffer unit; the power-on buffer unit is arranged between the rectification unit and the bus unit; The power-on buffer unit includes a first buffer module and a second buffer module; the first buffer module and the second buffer module are arranged between the rectification unit and the bus unit; Wherein, The first buffer module is configured to perform buffering processing on the first stage during the power-on process of the power supply of the drive device; the first stage is the stage from the power-on of the power supply of the drive device to the voltage of the bus unit rising to a set voltage threshold; The second buffer module is configured to perform buffering processing on the second stage during the power-on process of the power supply of the drive device; the second stage is the stage from the voltage of the bus unit rising to the set voltage threshold to the completion of the power-on of the power supply of the drive device; The first buffer module includes a first buffer switch module, a first resistor module, and a thyristor module; The second buffer module includes a second resistor module, an inductor module, and a second buffer switch module; Wherein, The first buffer switch module, the first resistor module, the second resistor module, and the inductor module are connected in series between the first connection end of the rectification unit and the first connection end of the bus unit; The thyristor module is arranged between the first connection end of the rectification unit and the common end between the first resistor module and the second resistor module; The second buffer switch module is arranged between the common end between the first resistor module and the second resistor module and the first connection end of the bus unit.

2. The power supply control device of the drive device according to claim 1, characterized in that, The power supply control device of the drive device further includes a braking unit; the braking unit is located between the power-on buffer unit and the bus unit, and is arranged between the first connection end and the second connection end of the bus unit; Wherein, the braking unit is configured to release the energy of the bus unit to reduce the bus voltage of the bus unit when the bus voltage of the bus unit reaches a set maximum voltage threshold.

3. The power supply control device of the drive device according to claim 2, characterized in that, The braking unit includes a braking switch module; When the bus voltage of the bus unit reaches the set maximum voltage threshold, the braking switch module cooperates with the second buffer switch module to release the energy of the bus unit through the second resistor module.

4. The power supply control device of the drive device according to claim 3, characterized in that, The power supply control device of the drive device further includes a PFC unit; The PFC unit is configured to improve the power factor of the power supply control device of the drive device.

5. The power supply control device of the drive device according to claim 4, characterized in that The power supply control device of the drive device further includes a PFC switch module, a first diode module, and a second diode module; Wherein, the inductor module, the PFC switch module, the first diode module, and the second diode module form a PFC circuit; The inductor module is connected to the anode of the second diode module; the cathode of the second diode module is connected to the first connection end of the bus unit; the anode of the first diode module is connected to the first connection end of the bus unit; the cathode of the first diode module is connected to the second connection end of the PFC switch module; the first connection end of the PFC switch module is connected to the thyristor module; The first connection end of the second buffer switch module is connected to the common end of the first resistor module and the second resistor module; the second connection end of the second buffer module is connected to the anode of the second diode module; the first connection end of the braking switch module is connected to the anode of the second diode module; the second connection end of the braking switch module is connected to the second connection end of the bus unit.

6. A driving device, characterized in that, Comprising: The power control device of the driving device according to any one of claims 1 to 5.

7. A power control method for a driving device as claimed in claim 6, characterized in that, Comprising: When the power control device of the driving device includes a first buffer switch module, a second buffer switch module, a thyristor module, a braking switch module and a PFC switch module, in the first stage of power-on buffering of the driving device, control the first buffer switch module to close, control the second buffer switch module to conduct, control the thyristor module to turn off, control the braking switch module to turn off, and control the PFC switch module to turn off; In the second stage of power-on buffering of the driving device, control the second buffer switch module to turn off, control the first buffer switch module to open, and control the thyristor module to conduct.

8. The power supply control method of the drive device according to claim 7, characterized in that, Further comprising: After the second stage of power-on buffering of the driving device is completed, control the PFC switch module to conduct to control the normal operation of the power supply of the driving device.

9. The power supply control method of the drive device according to claim 8, characterized in that, Further comprising: When the power supply of the driving device is operating normally, if the bus voltage of the bus unit reaches the set maximum voltage threshold, control the thyristor module to turn off, control the PFC switch module to turn off, control the second buffer switch module to conduct, control the braking switch module to conduct, so that the braking switch module, the second resistor module and the first diode module form a discharge circuit to release the bus voltage of the bus unit.

Images