Three-phase power supply circuit and three-phase power supply device

Abstract

The present application provides a three-phase power supply circuit and a three-phase power supply device, including a three-phase AC source, a clamping unit and a first switch unit; the three first ends of the clamping unit are respectively connected to the three-phase AC source through three loads, and the two second ends of the clamping unit are respectively connected to the two ends of the first switch unit, for clamping the absolute value of the voltage at the two second ends to a first voltage value range or a zero voltage value; when the first switch unit is in a first on state, the clamping unit clamps the absolute value of the voltage at the two second ends to a zero voltage value, so that the current paths of the three phase voltages provided to the three loads are simultaneously turned on; when the first switch unit is in a first off state, the clamping unit clamps the absolute value of the voltage at the two second ends to a first voltage value range, so that the current paths of the three phase voltages provided to the three loads are simultaneously turned off. The present application can provide or stop providing electric energy to the three loads at the same time as needed.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a three-phase power supply circuit and a three-phase power supply device having the three-phase power supply circuit. Background Art

[0002] Three-phase power supply is a common power supply method, widely used in industrial and commercial fields. Since the waveforms of voltage and current of three-phase power supply are symmetrical, it makes three-phase power supply more efficient and stable than single-phase power supply in many applications, and also makes three-phase power supply better balance load and reduce voltage fluctuation. Therefore, three-phase power supply is more suitable for providing power to three independent loads. However, how to quickly, conveniently and synchronously provide or stop providing power to three loads at the same time when the three loads need to be controlled synchronously has become a problem that needs to be considered. Summary of the invention

[0003] The present application provides a three-phase power supply circuit and a three-phase power supply device, which can quickly, conveniently and synchronously provide or stop providing electrical energy to three loads at the same time.

[0004] In a first aspect, a three-phase power supply circuit is provided, the three-phase power supply circuit comprising a three-phase AC source, a clamping unit and a first switch unit; the three-phase AC source has three output terminals, and the three-phase AC source is used to output three phase voltages respectively through the three output terminals; the clamping unit has three first terminals and two second terminals, the three first terminals of the clamping unit are respectively connected to the three output terminals of the three-phase AC source through three loads, each load is connected between a corresponding output terminal and a first terminal, the two second terminals of the clamping unit are respectively connected to the two ends of the first switch unit, and the clamping unit is used to clamp the absolute value of the voltage at the two second terminals to a first voltage value range or a zero voltage value, wherein the minimum voltage value of the first voltage value range is greater than the maximum voltage absolute value of any phase voltage; the first switch unit has a first on state and a first off state, wherein, when the first switch unit is in the first on state, the clamping unit clamps the absolute values ​​of the voltages at the two second ends to the zero voltage value, so that the current paths provided by the three phase voltages to the three loads are simultaneously turned on, so that the electric energy of the three phase voltages is correspondingly and simultaneously provided to the three loads; when the first switch unit is in the first off state, the clamping unit clamps the absolute values ​​of the voltages at the two second ends to the first voltage value range, so that the current paths provided by the three phase voltages to the three loads are simultaneously turned off, so that the electric energy of the three phase voltages is stopped from being provided to the three loads simultaneously.

[0005] In a possible implementation, the clamping unit includes three clamping switch modules, the input ends of the three clamping switch modules are respectively connected to the three first ends of the clamping unit, and the three clamping switch modules are connected in parallel between the two second ends of the clamping unit; wherein, when the first switch unit is in a first on state, the two second ends of the clamping unit are connected, each clamping switch module is disconnected, and the voltage values ​​of both ends of each clamping switch module connected to the two second ends of the clamping unit are clamped to the zero voltage value, thereby clamping the absolute value of the voltage at the two second ends of the clamping unit to the zero voltage value; when the first switch unit is in a first off state, the connection between the two second ends of the clamping unit is disconnected, the three clamping switch modules are selectively turned on according to the three phase voltages, and the sum of the absolute values ​​of the voltages of one end of the three clamping switch modules connected to the same second end of the clamping unit is clamped to the first voltage value range, thereby clamping the absolute values ​​of the voltages at the two second ends of the clamping unit to the first voltage value range.

[0006] In a possible implementation, each clamp switch module includes a first diode and a second diode, the connection point between the anode of each first diode and the cathode of the corresponding second diode is the input end of the corresponding clamp switch module, the cathode of each first diode is connected to one of the second ends of the clamp unit, and the anode of each second diode is connected to the other second end of the clamp unit; wherein, when the first switch unit is in a first on state, each first diode and each second diode are disconnected, so that each clamp switch module is disconnected; when the first switch unit is in a first off state, each first diode is turned on in the positive half cycle of the corresponding phase voltage, and each second diode is turned on in the negative half cycle of the corresponding phase voltage, so that each clamp switch module can be selectively turned on according to the corresponding phase voltage.

[0007] In a possible implementation, the first switch unit includes a first switch, two ends of the first switch are two ends of the first switch unit, and the first switch is turned on or off so that the first switch unit is correspondingly in a first on state or a first off state.

[0008] In a possible implementation, the three-phase power supply circuit further includes a second switch unit, which is connected between the three output terminals of the three-phase AC source and the three loads; wherein the second switch unit has a second on-state and a second off-state, and when the second switch unit is in the second on-state, the connection paths between the three output terminals of the three-phase AC source and the three loads are simultaneously turned on; when the second switch unit is in the second off-state, the connection paths between the three output terminals of the three-phase AC source and the three loads are simultaneously turned off.

[0009] In a possible implementation, the second switch unit switches from the second disconnected state / first disconnected state to the second conductive state / first conductive state correspondingly with the first switch unit with a difference of the first time period, so that the current paths for providing the electric energy of the three phase voltages to the three loads are delayed and turned on at the same time after the first time period, so that the electric energy of the three phase voltages is delayed and provided to the three loads correspondingly and simultaneously after the first time period; and the second switch unit switches from the second conductive state / first conductive state to the second disconnected state / first disconnected state correspondingly with the first time period with a difference of the first time period, and when any one of the second switch unit and the first switch unit switches states, the current paths for providing the electric energy of the three phase voltages to the three loads are disconnected at the same time, so that the electric energy of the three phase voltages stops being provided to the three loads at the same time.

[0010] In one possible implementation, after the first time period in which the second switch unit switches from the second disconnected state to the second conductive state, the first switch unit switches from the first disconnected state to the first conductive state, so that the current paths through which the electric energy of the three phase voltages is provided to the three loads are delayed and turned on at the same time after the first time period; when the first switch unit switches from the first conductive state to the first disconnected state, so that the current paths through which the electric energy of the three phase voltages is provided to the three loads are disconnected at the same time, after the first time period, the second switch unit switches from the second conductive state to the second disconnected state.

[0011] In a possible implementation, the second switch unit includes one or more mechanical switches, and the first switch unit includes one or more electronic switches.

[0012] In a possible implementation, the second switch unit includes a second switch, a third switch and a fourth switch, one end of the second switch, one end of the third switch and one end of the fourth switch are respectively connected to the three output ends of the three-phase AC source, and the other end of the second switch, the other end of the third switch and the other end of the fourth switch are respectively connected to the three loads; wherein the second switch, the third switch and the fourth switch are turned on or off at the same time, so that the second switch unit is in a second on state or a second off state correspondingly.

[0013] In the second aspect, a three-phase power supply device is also provided, and the three-phase power supply device includes a three-phase power supply circuit. The three-phase power supply circuit includes a three-phase AC source, a clamping unit and a first switch unit; the three-phase AC source has three output terminals, and the three-phase AC source is used to output three phase voltages respectively through the three output terminals; the clamping unit has three first terminals and two second terminals, and the three first terminals of the clamping unit are respectively connected to the three output terminals of the three-phase AC source through three loads, each load is connected between a corresponding output terminal and a first terminal, and the two second terminals of the clamping unit are respectively connected to the two ends of the first switch unit, and the clamping unit is used to clamp the absolute value of the voltage at the two second terminals to a first voltage value range or a zero voltage value, wherein the minimum voltage value of the first voltage value range is greater than the maximum voltage value of any phase voltage. The first switch unit has a first on-state and a first off-state, wherein when the first switch unit is in the first on-state, the clamping unit clamps the absolute values ​​of the voltages at the two second ends to the zero voltage value, so that the current paths provided by the three phase voltages to the three loads are simultaneously turned on, thereby making the electric energy of the three phase voltages be correspondingly and simultaneously provided to the three loads; when the first switch unit is in the first off-state, the clamping unit clamps the absolute values ​​of the voltages at the two second ends to the first voltage value range, so that the current paths provided by the three phase voltages to the three loads are simultaneously turned off, thereby making the electric energy of the three phase voltages stop being provided to the three loads simultaneously.

[0014] The three-phase power supply circuit and the three-phase power supply device of the present application are configured by providing a clamping unit connected to the three output ends of the three-phase AC source through three loads, and providing a first switch unit connected to the two second ends of the clamping unit, and configuring that when the first switch unit is in a first on state or a first off state, the clamping unit clamps the absolute value of the voltage at the two second ends to a zero voltage value or a first voltage value range, so that the current paths of the three phase voltages provided to the three loads are simultaneously turned on or disconnected, so as to realize back-end control. When the three loads need to be controlled synchronously, electric energy can be quickly, conveniently and synchronously provided or stopped from being provided to the three loads at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background technology, the drawings required for use in the embodiments of the present application or the background technology will be described below.

[0016] Figure 1 Schematic diagram of a three-phase power supply circuit in an embodiment of the present application.

[0017] Figure 2 FIG. 4 is a circuit diagram of a clamping unit in an embodiment of the present application.

[0018] Figure 3 The voltage waveform diagram is a diagram showing that the absolute values ​​of the voltages at the two second ends of the clamping unit and the three phase voltages in one embodiment of the present application are clamped to a first voltage value range.

[0019] Figure 4 The voltage waveform diagram is a diagram showing that the absolute values ​​of the voltages at the two second terminals of the three phase voltages and the two second terminals of the clamping unit in an embodiment of the present application are clamped to a zero voltage value.

[0020] Figure 5 It is a block diagram of a three-phase power supply circuit in another embodiment of the present application.

[0021] Figure 6 It is a block diagram of a three-phase power supply circuit in another embodiment of the present application.

[0022] Figure 7 Schematic diagram of a three-phase power supply device in one embodiment of the present application.

[0023] Explanation of the accompanying drawings: 10, three-phase power supply circuit, 100, three-phase AC source, O1, output end, U1, phase voltage, L1, load, 200, clamping unit, T1, first end, T2, second end, 210, clamping switch module, D1, first diode, D2, second diode, 300, first switch unit, S1, first switch, 400, second switch unit, S2, second switch, S3, third switch, S4, fourth switch, 500, control unit, 1000, three-phase power supply device. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] In the description of the embodiments of the present application, it should be noted that the terms "upper", "lower", "front", "rear", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not imply or indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0026] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0027] In the following, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more.

[0028] In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0029] See also Figure 1 , Figure 1 FIG. 1 is a block diagram of a three-phase power supply circuit in an embodiment of the present application. Figure 1 As shown, the present application provides a three-phase power supply circuit 10, which includes a three-phase AC source 100, a clamping unit 200 and a first switch unit 300; the three-phase AC source 100 has three output terminals O1, and the three-phase AC source 100 is used to output three phase voltages U1 respectively through the three output terminals O1; the clamping unit 200 has three first terminals T1 and two second terminals T2, and the three first terminals T1 of the clamping unit 200 are respectively connected to the three output terminals O1 of the three-phase AC source 100 through three loads L1, each load L1 is connected between a corresponding output terminal O1 and a first terminal T1, and the two second terminals T2 of the clamping unit 200 are respectively connected to the two ends of the first switch unit 300, and the clamping unit 200 is used to clamp the absolute value of the voltage at the two second terminals T2 to a first voltage value range or zero voltage. value, wherein the minimum voltage value of the first voltage value range is greater than the maximum voltage absolute value of any phase voltage U1; the first switch unit 300 has a first on state and a first off state, wherein when the first switch unit 300 is in the first on state, the clamping unit 200 clamps the absolute values ​​of the voltages at the two second terminals T2 to a zero voltage value, so that the current paths provided by the three phase voltages U1 to the three loads L1 are simultaneously turned on, so that the electric energy of the three phase voltages U1 is correspondingly and simultaneously provided to the three loads L1; when the first switch unit 300 is in the first off state, the clamping unit 200 clamps the absolute values ​​of the voltages at the two second terminals T2 to the first voltage value range, so that the current paths provided by the three phase voltages U1 to the three loads L1 are simultaneously turned off, so that the electric energy of the three phase voltages U1 is simultaneously stopped from being provided to the three loads L1.

[0030] Thus, the above-mentioned three-phase power supply circuit 10 in the present application is configured by setting a clamping unit 200 that is respectively connected to the three output terminals O1 of the three-phase AC source 100 through three loads L1, and setting a first switch unit 300 that is respectively connected to the two second terminals T2 of the clamping unit 200, and configuring that when the first switch unit 300 is in a first on state or a first off state, the clamping unit 200 clamps the absolute value of the voltage at the two second terminals T2 to a zero voltage value or a first voltage value range, so that the current paths of the three phase voltages U1 provided to the three loads L1 are simultaneously turned on or disconnected, so as to realize back-end control. When the three loads L1 need to be controlled synchronously, electric energy can be quickly, conveniently and synchronously provided or stopped from being provided to the three loads L1 at the same time.

[0031] Specifically, the three-phase AC source 100 may include three single-phase AC sources connected to a neutral point, each single-phase AC source having an output terminal O1 and outputting a phase voltage U1 respectively, wherein the waveform parameters of the three phase voltages U1 including the maximum voltage absolute value, period, frequency, etc. are the same, and the phase difference between the three phase voltages U1 is 120 degrees.

[0032] It should be noted that the clamping unit 200 clamps the absolute values ​​of the voltages at the two second terminals T2 to the first voltage value range, that is, the absolute values ​​of the voltages at the two second terminals T2 can only fluctuate within the first voltage value range. Furthermore, when the clamping unit 200 clamps the absolute values ​​of the voltages at the two second ends T2 to the first voltage value range, the voltage value at one of the second ends T2 is within the positive first voltage value range, and the voltage value at the other second end T2 is within the negative first voltage value range; when the clamping unit 200 clamps the absolute values ​​of the voltages at the two second ends T2 to the zero voltage value, it does not mean that the zero voltage value is 0 volts. Ideally, the clamping unit 200 can clamp the absolute values ​​of the voltages at the two second ends T2 to a zero voltage value of 0 volts. However, due to the presence of electronic components such as diodes and switches in the clamping unit 200 and the first switch unit 300, the clamping unit 200 can actually clamp the absolute values ​​of the voltages at the two second ends T2 to a zero voltage value that is not 0 volts, that is, the zero voltage value is below a voltage threshold, wherein the voltage threshold can be set according to specific needs, for example, the voltage threshold can be 1 volt.

[0033] Specifically, the direction of current flow in the current path provided by the three phase voltages U1 to the three loads L1 is defined as from the front end to the rear end of the three-phase power supply circuit 10, that is, the three-phase AC source 100, the three loads L1, the clamping unit 200 and the first switch unit 300 are sequentially from the front end to the rear end. Thus, when the first switch unit 300 is in the first conduction state, the clamping unit 200 clamps the absolute values ​​of the voltages at the two second terminals T2 to a zero voltage value, that is, the absolute value of the voltage at the rear end is a zero voltage value, and the absolute value of the voltage at the three output terminals O1 of the three-phase AC source 100 is the maximum absolute value of the voltage of the three phase voltages U1, that is, the absolute value of the voltage at the front end is the maximum absolute value of the voltage of the three phase voltages U1. Since the absolute value of the voltage at the front end is much greater than the absolute value of the voltage at the rear end, the current paths provided by the three phase voltages U1 to the three loads L1 are simultaneously turned on, so that the electric energy of the three phase voltages U1 is correspondingly and simultaneously provided to the three loads L1, and the absolute value of the voltage at the rear end is a zero voltage value, and the electric energy of the three phase voltages U1 will not be consumed or will only be consumed very little, so that the electric energy of the three phase voltages U1 can be maximized. The three phase voltages U1 are provided to the three loads L1 to a certain extent, thereby improving the efficiency of the three-phase power supply circuit 10; when the first switch unit 300 is in the first disconnected state, the clamping unit 200 clamps the absolute values ​​of the voltages at the two second ends T2 to the first voltage value range, that is, the absolute value of the voltage at the rear end fluctuates within the first voltage value range, and the absolute value of the voltage at the front end is still the maximum absolute value of the voltage of the three phase voltages U1. Since the absolute value of the voltage at the front end is much smaller than the absolute value of the voltage at the rear end, the current paths provided by the three phase voltages U1 to the three loads L1 are disconnected at the same time, so that the electric energy of the three phase voltages U1 is stopped from being provided to the three loads L1 at the same time, and there is no need to set electronic components such as switches between the three output ends O1 of the three-phase AC source 100 and the three loads L1, and the current paths provided by the three phase voltages U1 to the three loads L1 can be disconnected at the same time.

[0034] Please also read Figure 2 , Figure 3 , Figure 4 , Figure 2 is a circuit diagram of a clamping unit in an embodiment of the present application, Figure 3 is a voltage waveform diagram of the three phase voltages and the voltage absolute values ​​at the two second ends of the clamping unit in an embodiment of the present application being clamped to a first voltage value range, Figure 4 1 is a voltage waveform diagram of the three phase voltages and the voltage absolute values ​​at the two second terminals of the clamping unit in an embodiment of the present application being clamped to zero voltage value. Figure 2 , Figure 3 , Figure 4As shown, the clamping unit 200 includes three clamping switch modules 210, the input ends of the three clamping switch modules 210 are respectively connected to the three first ends T1 of the clamping unit 200, and the three clamping switch modules 210 are connected in parallel between the two second ends T2 of the clamping unit 200; wherein, when the first switch unit 300 is in the first on state, the two second ends T2 of the clamping unit 200 are connected, each clamping switch module 210 is disconnected, and the voltage values ​​of the two ends where each clamping switch module 210 is respectively connected to the two second ends T2 of the clamping unit 200 are clamped to zero voltage. voltage value, thereby clamping the absolute value of the voltage at the two second ends T2 of the clamp unit 200 to a zero voltage value; when the first switch unit 300 is in the first disconnected state, the connection between the two second ends T2 of the clamp unit 200 is disconnected, and the three clamp switch modules 210 are selectively turned on according to the three phase voltages U1, respectively, and the sum of the absolute values ​​of the voltages at one end of the three clamp switch modules 210 connected to the same second end T2 of the clamp unit 200 is clamped to a first voltage value range, thereby clamping the absolute values ​​of the voltages at the two second ends T2 of the clamp unit 200 to the first voltage value range.

[0035] Therefore, the above-mentioned three-phase power supply circuit 10 in the present application is configured such that the input ends of the three clamp switch modules 210 of the clamp unit 200 are respectively connected to the three first ends T1 of the clamp unit 200, and the three clamp switch modules 210 are connected in parallel between the two second ends T2 of the clamp unit 200. When the first switch unit 300 is in the first on-state, each clamp switch module 210 is disconnected, and the voltage values ​​at both ends of each clamp switch module 210 respectively connected to the two second ends T2 of the clamp unit 200 are clamped to a zero voltage value, thereby clamping the absolute value of the voltage at the two second ends T2 of the clamp unit 200 to a zero voltage value; and when the first switch unit 300 is in the first off-state, the three clamp switch modules 210 are selectively turned on according to the three phase voltages U1, respectively, and the sum of the absolute values ​​of the voltages at one end of the three clamp switch modules 210 connected to the same second end T2 of the clamp unit 200 is clamped to a first voltage value range, thereby clamping the absolute values ​​of the voltages at the two second ends T2 of the clamp unit 200 to the first voltage value range.

[0036] It should be noted that the second end T2 where the clamping unit 200 clamps the absolute value of the voltage to the positive first voltage value range is defined as the upper end, and the other second end T2 where the clamping unit 200 clamps the absolute value of the voltage to the negative first voltage value range is defined as the lower end. Figure 4 As shown, the voltage waveforms of the three phase voltages U1 and the voltage absolute values ​​at the two second terminals T2 of the clamping unit 200 are clamped to zero voltage values ​​using the Vt rectangular coordinate system, where V is voltage and t is time. Figure 4The V+ shown is the maximum positive voltage value of the three phase voltages U1, V- is the maximum negative voltage value of the three phase voltages U1, V0 is the zero voltage value, and U2 is the voltage waveform of the upper end or the lower end. When the first switch unit 300 is in the first conduction state, since the two second ends T2 of the clamp unit 200 are connected, the voltage values ​​of the two ends of each clamp switch module 210 respectively connected to the two second ends T2 of the clamp unit 200 are clamped to the zero voltage value, and the sum of the absolute values ​​of the voltages of one end of the three clamp switch modules 210 connected to the same second end T2 of the clamp unit 200 is the zero voltage value, that is, the sum of the absolute values ​​of the voltages at the upper end is the zero voltage value, and the sum of the absolute values ​​of the voltages at the lower end is also the zero voltage value. At this time, the electric energy of the three phase voltages U1 is correspondingly and simultaneously provided to the three loads L1, and the current waveform is three sinusoidal waveforms, and the phase difference of the three sinusoidal waveforms is 120 degrees; as shown in FIG. Figure 3 As shown, the voltage waveform of the three phase voltages U1 and the voltage absolute values ​​at the two second terminals T2 of the clamping unit 200 are clamped to the first voltage value range in the Vt rectangular coordinate system, where V is voltage and t is time. Figure 3 The V+ shown is the maximum positive voltage value of the three phase voltages U1, V- is the maximum negative voltage value of the three phase voltages U1, V0 is the zero voltage value, Vr1 is the first voltage value range, U2 is the voltage waveform of the upper end, and the voltage waveform of the lower end is not shown in the figure. The absolute value of its voltage waveform is the same as that of U2. When the first switch unit 300 is in the first disconnected state, since the connection between the two second ends T2 of the clamping unit 200 is disconnected, the sum of the absolute values ​​of the voltages of one end of the three clamping switch modules 210 connected to the same second end T2 of the clamping unit 200 fluctuates periodically within the first voltage value range, that is, the sum of the absolute values ​​of the voltages at the upper ends fluctuates periodically within the first voltage value range, and the sum of the absolute values ​​of the voltages at the lower ends also fluctuates periodically within the first voltage value range. Figure 3 It can be seen that the minimum value of Vr1 is greater than V+ of any phase voltage U1 . At this time, the electric energy of the three phase voltages U1 is correspondingly and simultaneously stopped from being provided to the three loads L1 .

[0037] like Figure 2As shown, each clamp switch module 210 includes a first diode D1 and a second diode D2, the connection point between the anode of each first diode D1 and the cathode of the corresponding second diode D2 is the input terminal of the corresponding clamp switch module 210, the cathode of each first diode D1 is connected to one of the second terminals T2 of the clamp unit 200, and the anode of each second diode D2 is connected to the other second terminal T2 of the clamp unit 200; wherein, when the first switch unit 300 is in the first on state, each first diode D1 and each second diode D2 are disconnected, so that each clamp switch module 210 is disconnected; when the first switch unit 300 is in the first off state, each first diode D1 is turned on in the positive half cycle of the corresponding phase voltage U1, and each second diode D2 is turned on in the negative half cycle of the corresponding phase voltage U1, so that each clamp switch module 210 can be selectively turned on according to the corresponding phase voltage U1.

[0038] Therefore, the above-mentioned three-phase power supply circuit 10 in the present application, by setting each clamp switch module 210 to include a first diode D1 and a second diode D2, has formed a rectifier bridge, and no additional switching operation is required to achieve that when the first switch unit 300 is in the first conduction state, each first diode D1 and each second diode D2 are disconnected, so that each clamp switch module 210 is disconnected; and when the first switch unit 300 is in the first disconnection state, each first diode D1 is turned on in the positive half cycle of the corresponding phase voltage U1, and each second diode D2 is turned on in the negative half cycle of the corresponding phase voltage U1, so that each clamp switch module 210 can be selectively turned on according to the corresponding phase voltage U1.

[0039] Specifically, the three phase voltages U1 are defined as the first phase voltage U1, the second phase voltage U1 and the third phase voltage U1, which correspond to the first first diode D1, the second first diode D1 and the third first diode D1 from the front end to the rear end, and correspond to the first second diode D2, the second second diode D2 and the third second diode D2 from the front end to the rear end. Since the phase difference between the three phase voltages U1 is 120 degrees, when the first switch unit 300 is in the first disconnection state, two of the diodes are turned on and the other diode is turned off. For example, the first first diode D1 and the second first diode D1, the second first diode D1 and the third first diode D1, the third first diode D1 and the first first diode D1 are turned on in sequence, and the third first diode D1, the first first diode D1 and the second first diode D1 are turned off accordingly. Similarly, the first second diode D2 and the second second diode D2, the second second diode D2 and the third second diode D2, the third second diode D2 and the first second diode D2 are turned on in sequence, and the third second diode D2, the first second diode D2 and the second second diode D2 are turned off accordingly. Thus, when the first switch unit 300 is in the first disconnected state, the voltage amplitude at the connection point of the three first diodes D1 is 2√3 times the maximum positive voltage value of any phase voltage U1, and the voltage effective value is √6 times the maximum positive voltage value of any phase voltage U1, that is, the voltage effective value of the upper end is √6 times the maximum positive voltage value of any phase voltage U1, and the voltage amplitude at the connection point of the three second diodes D2 is 2√3 times the maximum negative voltage value of any phase voltage U1, and the voltage effective value is √6 times the maximum negative voltage value of any phase voltage U1, that is, the voltage effective value of the lower end is √6 times the maximum negative voltage value of any phase voltage U1, thereby always clamping the absolute value of the voltage at the two second ends T2 of the clamping unit 200 to the first voltage value range.

[0040] See also Figure 5 , Figure 5 FIG. 1 is a block diagram of a three-phase power supply circuit in another embodiment of the present application. Figure 5 As shown, the three-phase power supply circuit 10 also includes a second switch unit 400, which is connected between the three output terminals O1 of the three-phase AC source 100 and the three loads L1; wherein the second switch unit 400 has a second on state and a second off state, and when the second switch unit 400 is in the second on state, the connection paths between the three output terminals O1 of the three-phase AC source 100 and the three loads L1 are simultaneously turned on; when the second switch unit 400 is in the second off state, the connection paths between the three output terminals O1 of the three-phase AC source 100 and the three loads L1 are simultaneously turned off.

[0041] Therefore, the above-mentioned three-phase power supply circuit 10 in the present application, by providing a second switch unit 400 connected between the three output terminals O1 of the three-phase AC source 100 and the three loads L1, can at least directly disconnect the connection path between the three output terminals O1 of the three-phase AC source 100 and the three loads L1 when a failure occurs in the rear-end clamping unit 200 and the first switch unit 300 and the electric energy of the three phase voltages U1 cannot be simultaneously stopped from being provided to the three loads L1.

[0042] See also Figure 6 , Figure 6 FIG. 1 is a block diagram of a three-phase power supply circuit in another embodiment of the present application. Figure 6 As shown, the first switch unit 300 includes a first switch S1 , two ends of the first switch S1 are two ends of the first switch unit 300 , and the first switch S1 is turned on or off, so that the first switch unit 300 is in a first on state or a first off state correspondingly.

[0043] Therefore, the above-mentioned three-phase power supply circuit 10 in the present application, by setting the first switch unit 300 to include the first switch S1, can simply and conveniently make the first switch unit 300 correspondingly in the first on state or the first off state, and then correspondingly connect or disconnect the two second ends T2 of the clamping unit 200.

[0044] In one or more embodiments, the second switch unit 400 switches from the second disconnected state / first disconnected state to the second conductive state / first conductive state correspondingly with the first switch unit 300 with a difference of the first time period, so that the current paths through which the electric energy of the three phase voltages U1 is provided to the three loads L1 are delayed by the first time period and are turned on at the same time, so that the electric energy of the three phase voltages U1 is delayed by the first time period and is provided to the three loads L1 correspondingly and simultaneously; and the second switch unit 400 switches from the second conductive state / first conductive state to the second disconnected state / first disconnected state correspondingly with the first time period, and when any one of the second switch unit 400 and the first switch unit 300 switches states, the current paths through which the electric energy of the three phase voltages U1 is provided to the three loads L1 are disconnected at the same time, so that the electric energy of the three phase voltages U1 stops being provided to the three loads L1 at the same time.

[0045] Thus, the above-mentioned three-phase power supply circuit 10 in the present application, when the three-phase power supply circuit 10 includes both the first switch unit 300 and the second switch unit 400, can realize soft switching of either the second switch unit 400 or the first switch unit 300 by configuring the second switch unit 400 to switch from the second disconnected state / first disconnected state to the second conductive state / first conductive state corresponding to a first time period difference with the first switch unit 300, thereby reducing the loss of either the second switch unit 400 or the first switch unit 300 and extending the service life.

[0046] Specifically, when any one of the second switch unit 400 and the first switch unit 300 switches state first, no current flows through the three-phase power supply circuit 10. At this time, when the other one of the second switch unit 400 and the first switch unit 300 is switched state, zero current conduction can be achieved, thereby reducing the loss of the other one of the second switch unit 400 and the first switch unit 300.

[0047] In one or more embodiments, the first time period may be set according to specific needs. Since the purpose is to achieve soft switching, the first time period may refer to the response time of any switching state of the second switch unit 400 and the first switch unit 300.

[0048] Further, after the first time period when the second switch unit 400 switches from the second disconnected state to the second on state, the first switch unit 300 switches from the first disconnected state to the first on state, so that the current paths through which the electric energy of the three phase voltages U1 is provided to the three loads L1 are delayed and turned on at the same time after the first time period; when the first switch unit 300 switches from the first on state to the first disconnected state, so that the current paths through which the electric energy of the three phase voltages U1 is provided to the three loads L1 are disconnected at the same time, after the first time period, the second switch unit 400 switches from the second on state to the second disconnected state.

[0049] Therefore, in the above three-phase power supply circuit 10 in the present application, generally speaking, the first switch unit 300 only needs Figure 6 The first switch S1 shown is sufficient, so that soft switching of the second switch unit 400 can be achieved.

[0050] like Figure 6As shown, the second switch unit 400 includes a second switch S2, a third switch S3 and a fourth switch S4, one end of the second switch S2, one end of the third switch S3 and one end of the fourth switch S4 are respectively connected to the three output ends O1 of the three-phase AC source 100, and the other end of the second switch S2, the other end of the third switch S3 and the other end of the fourth switch S4 are respectively connected to the three loads L1; wherein the second switch S2, the third switch S3 and the fourth switch S4 are simultaneously turned on or turned off, so that the second switch unit 400 is correspondingly in the second on state or the second off state.

[0051] Thus, in the above-mentioned three-phase power supply circuit 10 in the present application, when the second switch unit 400 includes the second switch S2, the third switch S3 and the fourth switch S4, the second switch S2, the third switch S3 and the fourth switch S4 are turned on or turned off at the same time, so that the second switch unit 400 is correspondingly in the second on state or the second off state, so that when the soft switching of the second switch unit 400 is realized, the second switch S2, the third switch S3 and the fourth switch S4 can all realize soft switching, thereby reducing the switching loss of the three switches.

[0052] In some other embodiments, the second switch unit 400 may include a fifth switch, which is a three-pole single-throw knife switch, and the three poles of the fifth switch are respectively connected between the three output terminals O1 of the three-phase AC source 100 and the three loads L1. The knife of the fifth switch is turned on or off, which makes it easier to make the three connection paths between the three output terminals O1 of the three-phase AC source 100 and the three loads L1 turned on or off at the same time.

[0053] like Figure 6 As shown, the second switch unit 400 includes one or more mechanical switches, and the first switch unit 300 includes one or more electronic switches.

[0054] Therefore, the above three-phase power supply circuit 10 in the present application can not only reduce the switching loss of one or more mechanical switches when implementing the soft switching of the second switch unit 400 by setting the second switch unit 400 to include one or more mechanical switches. And by setting the first switch unit 300 to include one or more electronic switches, it can also make the one or more electronic switches of the first switch unit 300 respond to state switching faster to reduce the first time period, and at the same time, one or more electronic switches are turned on or off by signal control, further reducing the switching loss of one or more electronic switches.

[0055] In particular, the second switch unit 400 includes one or more mechanical switches, and the first switch unit 300 includes one or more electronic switches. Two operation modes are also provided for the user. When it is necessary to stop supplying electric energy to the three loads L1 at the same time, the user can quickly select manual or electric operation mode according to the specific situation to switch the state of the second switch unit 400 or the first switch unit 300, thereby quickly, conveniently and synchronously stopping the supply of electric energy to the three loads L1 at the same time.

[0056] like Figure 5 As shown, the three-phase power supply circuit 10 further includes a control unit 500, and the control unit 500 is used to output corresponding control signals to control the corresponding switching states of the second switch unit 400 and / or the first switch unit 300.

[0057] Among them, the control unit 500 can be a general-purpose processor such as a central processing unit (CPU), or a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate logic devices, transistor logic devices and other logic control devices, or a microprocessor such as a micro control unit (MCU).

[0058] In some other embodiments, after the first time period in which the first switch unit 300 switches from the first disconnected state to the first on state, the second switch unit 400 switches from the second disconnected state to the second on state, so that the current paths through which the electric energy of the three phase voltages U1 is provided to the three loads L1 are delayed for the first time period and are turned on at the same time; when the second switch unit 400 switches from the second on state to the second disconnected state, so that the current paths through which the electric energy of the three phase voltages U1 is provided to the three loads L1 are disconnected at the same time, after the first time period, the first switch unit 300 switches from the first on state to the first disconnected state.

[0059] Further, in these embodiments, the second switch unit 400 may include one or more electronic switches, and the first switch unit 300 may include one or more mechanical switches.

[0060] Therefore, the above-mentioned three-phase power supply circuit 10 in the present application, as mentioned above, can also realize the soft switching of the first switch unit 300 according to specific needs.

[0061] The three-phase power supply circuit 10 of the present application can realize back-end control through the above-mentioned structure, and can also adopt multiple methods. When the three loads L1 need to be controlled synchronously, electric energy can be quickly, conveniently and synchronously provided or stopped to the three loads L1 at the same time. At the same time, fewer electronic components such as switches are used, which reduces the cost of electronic components, and realizes soft switching, which greatly reduces the switching loss of the switch.

[0062] See also Figure 7 , Figure 7 FIG. 1 is a block diagram of a three-phase power supply device in an embodiment of the present application. Figure 7 As shown, the present application further provides a three-phase power supply device 1000, and the three-phase power supply device 1000 includes the three-phase power supply circuit 10 in any of the aforementioned embodiments.

[0063] Please refer again Figure 1 .like Figure 1 As shown, the three-phase power supply circuit 10 includes a three-phase AC source 100, a clamping unit 200 and a first switch unit 300; the three-phase AC source 100 has three output terminals O1, and the three-phase AC source 100 is used to output three phase voltages U1 respectively through the three output terminals O1; the clamping unit 200 has three first terminals T1 and two second terminals T2, and the three first terminals T1 of the clamping unit 200 are respectively connected to the three output terminals O1 of the three-phase AC source 100 through three loads L1, each load L1 is connected between a corresponding output terminal O1 and a first terminal T1, and the two second terminals T2 of the clamping unit 200 are respectively connected to the two ends of the first switch unit 300, and the clamping unit 200 is used to clamp the absolute value of the voltage at the two second terminals T2 to a first voltage value range or a zero voltage value, wherein the first voltage The minimum voltage value of the voltage value range is greater than the maximum voltage absolute value of any phase voltage U1; the first switch unit 300 has a first on state and a first off state, wherein when the first switch unit 300 is in the first on state, the clamping unit 200 clamps the absolute values ​​of the voltages at the two second terminals T2 to a zero voltage value, so that the current paths provided by the three phase voltages U1 to the three loads L1 are simultaneously turned on, thereby enabling the electric energy of the three phase voltages U1 to be correspondingly and simultaneously provided to the three loads L1; when the first switch unit 300 is in the first off state, the clamping unit 200 clamps the absolute values ​​of the voltages at the two second terminals T2 to a first voltage value range, so that the current paths provided by the three phase voltages U1 to the three loads L1 are simultaneously turned off, thereby enabling the electric energy of the three phase voltages U1 to be stopped from being provided to the three loads L1 at the same time.

[0064] The more specific structure of the three-phase power supply circuit 10 can refer to the relevant content of the three-phase power supply circuit 10 in any of the aforementioned embodiments, which will not be repeated here.

[0065] The three-phase power supply circuit 10 and the three-phase power supply device 1000 of the present application can realize back-end control through the above-mentioned structure, and can also adopt multiple methods. When the three loads L1 need to be controlled synchronously, electric energy can be quickly, conveniently and synchronously provided or stopped to the three loads L1 at the same time. At the same time, fewer electronic components such as switches are used, which reduces the cost of electronic components, and realizes soft switching, which greatly reduces the switching loss of the switch.

[0066] The above description is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application; in the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A three-phase power supply circuit, characterized in that: The three-phase power supply circuit includes a three-phase AC source, a clamping unit and a first switch unit; The three-phase AC source has three output terminals, and the three-phase AC source is used to output three phase voltages through the three output terminals respectively; The clamping unit has three first ends and two second ends. The three first ends of the clamping unit are respectively connected to the three output ends of the three-phase AC source through three loads, each load is connected between a corresponding output end and a first end, and the two second ends of the clamping unit are respectively connected to the two ends of the first switch unit. The clamping unit is used to clamp the absolute values ​​of the voltages at the two second ends to a first voltage value range or a zero voltage value, wherein the minimum voltage value of the first voltage value range is greater than the maximum voltage absolute value of any phase voltage; The first switch unit has a first on state and a first off state, wherein when the first switch unit is in the first on state, the clamping unit clamps the absolute values ​​of the voltages at the two second ends to the zero voltage value, so that the current paths provided by the three phase voltages to the three loads are simultaneously turned on, so that the electric energy of the three phase voltages is correspondingly and simultaneously provided to the three loads; when the first switch unit is in the first off state, the clamping unit clamps the absolute values ​​of the voltages at the two second ends to the first voltage value range, so that the current paths provided by the three phase voltages to the three loads are simultaneously turned off, so that the electric energy of the three phase voltages is stopped from being provided to the three loads simultaneously; The three-phase power supply circuit further includes a second switch unit, which is connected between the three output terminals of the three-phase AC source and the three loads; wherein the second switch unit has a second on state and a second off state, and when the second switch unit is in the second on state, the connection paths between the three output terminals of the three-phase AC source and the three loads are simultaneously turned on; when the second switch unit is in the second off state, the connection paths between the three output terminals of the three-phase AC source and the three loads are simultaneously turned off; The second switch unit is switched from the second disconnected state / first disconnected state to the second conductive state / first conductive state correspondingly with the first time period difference from the first switch unit, so that the current paths for providing the electric energy of the three phase voltages to the three loads are delayed and turned on at the same time after the first time period, so that the electric energy of the three phase voltages is delayed and provided to the three loads correspondingly and simultaneously after the first time period; and the second switch unit is switched from the second conductive state / first conductive state to the second disconnected state / first disconnected state correspondingly with the first time period difference from the first switch unit, when any one of the second switch unit and the first switch unit switches states, the current paths for providing the electric energy of the three phase voltages to the three loads are disconnected at the same time, so that the electric energy of the three phase voltages stops being provided to the three loads at the same time.

2. The three-phase power supply circuit according to claim 1, characterized in that: The clamping unit includes three clamping switch modules, the input ends of the three clamping switch modules are respectively connected to the three first ends of the clamping unit, and the three clamping switch modules are connected in parallel between the two second ends of the clamping unit; wherein, when the first switch unit is in a first on state, the two second ends of the clamping unit are connected, each clamping switch module is disconnected, and the voltage values ​​of both ends of each clamping switch module connected to the two second ends of the clamping unit are clamped to the zero voltage value, thereby clamping the absolute value of the voltage at the two second ends of the clamping unit to the zero voltage value; when the first switch unit is in a first off state, the connection between the two second ends of the clamping unit is disconnected, the three clamping switch modules are selectively turned on according to the three phase voltages, and the sum of the absolute values ​​of the voltages of one end of the three clamping switch modules connected to the same second end of the clamping unit is clamped to the first voltage value range, thereby clamping the absolute values ​​of the voltages at the two second ends of the clamping unit to the first voltage value range.

3. The three-phase power supply circuit according to claim 2, characterized in that: Each clamp switch module includes a first diode and a second diode, the connection point between the anode of each first diode and the cathode of the corresponding second diode is the input end of the corresponding clamp switch module, the cathode of each first diode is connected to one of the second ends of the clamp unit, and the anode of each second diode is connected to the other second end of the clamp unit; wherein, when the first switch unit is in the first on state, each first diode and each second diode are disconnected, so that each clamp switch module is disconnected; when the first switch unit is in the first off state, each first diode is turned on in the positive half cycle of the corresponding phase voltage, and each second diode is turned on in the negative half cycle of the corresponding phase voltage, so that each clamp switch module can be selectively turned on according to the corresponding phase voltage.

4. The three-phase power supply circuit according to claim 1, characterized in that: The first switch unit includes a first switch, two ends of the first switch are two ends of the first switch unit, and the first switch is turned on or off, so that the first switch unit is in a first on state or a first off state correspondingly.

5. The three-phase power supply circuit according to claim 1, characterized in that: After the first time period when the second switch unit switches from the second disconnected state to the second turned-on state, the first switch unit switches from the first disconnected state to the first turned-on state, so that the current paths through which the electric energy of the three phase voltages is provided to the three loads are delayed and turned on at the same time after the first time period; when the first switch unit switches from the first turned-on state to the first disconnected state, so that the current paths through which the electric energy of the three phase voltages is provided to the three loads are disconnected at the same time, after the first time period, the second switch unit switches from the second turned-on state to the second disconnected state.

6. The three-phase power supply circuit according to claim 5, characterized in that: The second switch unit includes one or more mechanical switches, and the first switch unit includes one or more electronic switches.

7. The three-phase power supply circuit according to claim 1, characterized in that: The second switch unit includes a second switch, a third switch and a fourth switch, one end of the second switch, one end of the third switch and one end of the fourth switch are respectively connected to the three output ends of the three-phase AC source, and the other end of the second switch, the other end of the third switch and the other end of the fourth switch are respectively connected to the three loads; wherein the second switch, the third switch and the fourth switch are turned on or off at the same time, so that the second switch unit is in a second on state or a second off state correspondingly.

8. A three-phase power supply device, characterized in that: Comprising a three-phase power supply circuit as described in any one of claims 1-7.

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