Phase-shifting transformer and voltage conversion circuit, medical device

Abstract

The application discloses a phase-shifting transformer, a voltage conversion circuit and medical equipment. The phase-shifting transformer comprises a first primary winding and a second primary winding, the first primary winding and the second primary winding are connected in parallel, and there is a phase difference between the first primary winding and the second primary winding; a plurality of secondary windings, each secondary winding comprises a first coil and a second coil, the first coil corresponds to the first primary winding, the second coil corresponds to the second primary winding, there is a phase difference between the plurality of secondary windings, and there is a phase difference between the first coil and the second coil in each secondary winding. Therefore, the high-order harmonic of the primary side of the phase-shifting transformer can be effectively inhibited, the hardware cost is basically unchanged, and the performance-price ratio of the phase-shifting transformer is relatively high.

Description

Technical Field

[0001] This invention relates to the field of voltage conversion, and more particularly to a phase-shifting transformer and voltage conversion circuit, and medical equipment. Background Technology

[0002] In the field of voltage conversion, to power DC equipment using AC power from the grid, transformers and rectifier circuits are typically installed between the grid and the equipment to achieve AC-DC conversion. Since the equipment is usually not a resistive load, the secondary winding current of the transformer will experience waveform distortion, resulting in a higher number of high-order harmonics. These harmonics will superimpose onto the primary winding, causing it to also generate significant high-order harmonics, thus causing considerable pollution to the power grid. To address this, some technologies have proposed a multiphase rectifier circuit using a phase-shifting transformer, as referenced... Figure 1 As shown, this phase-shifting transformer uses two coils in each secondary winding. By utilizing the phase difference between the two coils, the induced current in the secondary winding is superimposed on the primary winding in a phase-shifted manner, thereby suppressing high-order harmonics in the primary winding and reducing pollution to the power grid.

[0003] The drawback of the phase-shifting transformers mentioned above is that, due to design limitations, Figure 1 The phase-shifting transformer shown has limited harmonic suppression capability, which means that the PF value (power correction factor) of the phase-shifting transformer can only reach a maximum of about 0.8, resulting in a low conversion efficiency of the phase-shifting transformer that is difficult to improve. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, the first objective of this invention is to propose a phase-shifting transformer. This transformer has a first primary winding and a second primary winding with a phase difference on the primary side, and corresponding first coils and second coils with phase differences are arranged in multiple secondary windings. When the transformer is operating normally, the currents in the multiple secondary winding coils can be superimposed onto the first primary winding and the second primary winding in a staggered phase, suppressing primary current harmonics. Simultaneously, since the first and second primary windings also have a phase difference, the primary currents after the staggered phase superposition can be further superimposed to further suppress primary current harmonics. This enhances the harmonic suppression performance of the phase-shifting transformer, improves its conversion efficiency, and maintains essentially the same hardware cost, thus improving the cost-effectiveness of the phase-shifting transformer and achieving overall optimization of the phase-shifting transformer.

[0005] The second objective of this invention is to provide a voltage conversion circuit.

[0006] The third objective of this invention is to provide a medical device.

[0007] To achieve the above objectives, a first aspect of the present invention provides a phase-shifting transformer, comprising: a first primary winding and a second primary winding, wherein the first primary winding and the second primary winding are connected in parallel and there is a phase difference between the first primary winding and the second primary winding; and a plurality of secondary windings, each secondary winding comprising a first coil and a second coil, wherein the first coil corresponds to the first primary winding and the second coil corresponds to the second primary winding, and there is a phase difference between the plurality of secondary windings, wherein there is a phase difference between the first coil and the second coil in each secondary winding.

[0008] According to an embodiment of the present invention, a phase-shifting transformer is provided on the primary side of the transformer with a first primary winding and a second primary winding having a phase difference, and correspondingly provided on the secondary windings with a first coil and a second coil having a phase difference. When the transformer is working normally, the current in the coils of the multiple secondary windings can be superimposed on the first primary winding and the first primary winding of the primary side in a phase-shifted manner, suppressing the primary current harmonics. At the same time, since the first primary winding and the second primary winding also have a phase difference, the primary current after phase-shifting superposition can be further superimposed in a phase-shifted manner to further suppress the primary current harmonics. This enhances the harmonic suppression performance of the phase-shifting transformer, improves the conversion efficiency of the phase-shifting transformer, and keeps the hardware cost basically unchanged, thereby improving the cost-effectiveness of the phase-shifting transformer and realizing the overall optimization of the phase-shifting transformer.

[0009] According to one embodiment of the present invention, a plurality of secondary windings include a first secondary winding and at least one pair of second secondary windings, wherein the phase of one of the second secondary windings in each pair of second secondary windings leads the phase of the first secondary winding, and the phase of the other second secondary winding in each pair of second secondary windings lags the phase of the first secondary winding.

[0010] According to one embodiment of the present invention, the phase of the first secondary winding is determined based on the phases of the first primary winding and the second primary winding.

[0011] According to one embodiment of the present invention, the phase of the first coil in the first secondary winding is the same as the phase of the first primary winding, and the phase of the second coil in the first secondary winding is the same as the phase of the second primary winding.

[0012] According to one embodiment of the present invention, the second primary winding and the second coil in each secondary winding each include at least one, and at least one second primary winding corresponds one-to-one with at least one second coil in each secondary winding.

[0013] According to one embodiment of the present invention, the phase difference between the first primary winding and each of the second primary windings is the same.

[0014] According to one embodiment of the present invention, the phase difference between the first primary winding and each second primary winding is 30° / n, where n is the number of second primary windings.

[0015] According to one embodiment of the present invention, the phase difference between the plurality of secondary windings is determined based on the number of secondary windings and the number of coils in each secondary winding.

[0016] According to one embodiment of the present invention, the phase difference between a plurality of secondary windings is determined in the following manner:

[0017]

[0018] Where δ1 is the phase difference between multiple secondary windings, M is the number of secondary windings, and N is the number of coils.

[0019] According to one embodiment of the present invention, the phase difference between multiple secondary windings includes a first phase difference between first coils in different secondary windings and a second phase difference between second coils in different secondary windings, wherein the value range of the first phase difference is -30° to 30° and the value range of the second phase difference is -60° to 0°.

[0020] According to one embodiment of the present invention, the phase difference between the first coil and the second coil in each secondary winding is determined based on the number of coils in each secondary winding.

[0021] According to one embodiment of the present invention, the phase difference between the first coil and the second coil in each secondary winding is determined by the following method:

[0022]

[0023] Where δ2 is the phase difference between the first and second coils in each secondary winding, and N is the number of coils.

[0024] According to one embodiment of the present invention, the number of turns of the first coil in the second secondary winding is determined based on the phase difference between the plurality of first coils, the voltage of the first primary winding, the voltage of the first coil, and the winding method of the first coil.

[0025] According to one embodiment of the present invention, the first coil is composed of a three-phase winding. When the winding method of the first primary winding is Y-connected and the winding method of the second coil of the second secondary winding is positive extended delta connection, the number of turns of the first coil in the second secondary winding is determined in the following way:

[0026]

[0027] Wherein, the sum of N2 and N3 is the number of turns of each phase winding of the first coil, N3 is used to determine the position of the center tap of each phase winding, δ3 is the phase difference between multiple first coils, VAB is the voltage of the first primary winding, Vab is the voltage of the first coil, and N1 is the number of turns of the first primary winding.

[0028] According to one embodiment of the present invention, the number of turns of the second coil in the second secondary winding is determined based on the phase difference between the plurality of second coils, the voltage of the second primary winding, the voltage of the second coil, and the winding method of the second coil.

[0029] According to one embodiment of the present invention, the second coil is composed of a three-phase winding. When the winding method of the second primary winding is delta connection and the winding method of the second coil of the second secondary winding is positive extended delta connection, the number of turns of the second coil in the second secondary winding is determined in the following way:

[0030]

[0031] Wherein, the sum of N2' and N3' is the number of turns in each phase winding of the second coil, N3' is used to determine the position of the center tap of each phase winding, δ4 is the phase difference between multiple second coils, VAB' is the voltage of the second primary winding, Vab' is the voltage of the second coil, and N1' is the number of turns in the second primary winding.

[0032] According to one embodiment of the present invention, the second coil is composed of a three-phase winding. When the winding method of the first primary winding is delta connection and the winding method of the second coil of the second secondary winding is reverse extended delta connection, the number of turns of the second coil in the second secondary winding is determined in the following way:

[0033]

[0034] Wherein, the sum of N2' and N3' is the number of turns in each phase winding of the second coil, N3' is used to determine the position of the center tap of each phase winding, δ4 is the phase difference between multiple second coils, VAB' is the voltage of the second primary winding, Vab' is the voltage of the second coil, and N1' is the number of turns in the second primary winding.

[0035] To achieve the above objectives, a second aspect of the present invention provides a voltage conversion circuit, including the aforementioned phase-shifting transformer.

[0036] According to the voltage conversion circuit of the present invention, the aforementioned phase-shifting transformer can improve the harmonic suppression performance and conversion efficiency of the voltage conversion circuit, while the hardware cost remains basically unchanged, making the voltage conversion circuit more cost-effective and achieving overall optimization of the voltage conversion circuit.

[0037] To achieve the above objectives, a third aspect of the present invention provides a medical device including the aforementioned phase-shifting transformer.

[0038] According to the medical device of the present invention, the aforementioned phase-shifting transformer can improve the harmonic suppression performance and conversion efficiency of the medical device, while the hardware cost remains basically unchanged, making the medical device more cost-effective and achieving overall optimization of the medical device.

[0039] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of a multiphase rectifier circuit according to related technologies;

[0041] Figure 2 This is a schematic diagram of the structure of a phase-shifting transformer according to an embodiment of the present invention;

[0042] Figure 3 This is a schematic diagram of a multiphase rectifier circuit according to an embodiment of the present invention;

[0043] Figure 4 This is a schematic diagram of the harmonic components of the phase current in a phase-shifting transformer in related technologies.

[0044] Figure 5 A schematic diagram of the harmonic components of the phase current of a phase-shifting transformer according to an embodiment of the present invention;

[0045] Figure 6 This is another type of multiphase rectifier circuit in related technologies;

[0046] Figure 7 This is a schematic diagram of the structure of a phase-shifting transformer according to another embodiment of the present invention;

[0047] Figure 8 This is a schematic diagram of the structure of a phase-shifting transformer according to yet another embodiment of the present invention;

[0048] Figure 9 This is a waveform diagram of the output voltage of a phase-shifting transformer according to an embodiment of the present invention;

[0049] Figures 10a-10d This is a schematic diagram of the winding method of the coil in the secondary winding according to an embodiment of the present invention;

[0050] Figures 11a-11d This is a vector analysis diagram of the secondary winding coil winding method according to some embodiments of the present invention;

[0051] Figure 12This is a schematic diagram of a voltage conversion circuit according to an embodiment of the present invention;

[0052] Figure 13 This is a schematic diagram of the structure of a medical device according to an embodiment of the present invention. Detailed Implementation

[0053] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0054] The following description, with reference to the accompanying drawings, describes the phase-shifting transformer and voltage conversion circuit, as well as the medical device, proposed in the embodiments of the present invention.

[0055] Figure 2 This is a schematic diagram of a phase-shifting transformer according to an embodiment of the present invention, with reference to... Figure 2 As shown, the phase-shifting transformer 100 includes: a first primary winding Y1 and a second primary winding Y2, and multiple secondary windings (F1 to FN).

[0056] The first primary winding Y1 and the second primary winding Y2 are connected in parallel, and there is a phase difference between the first primary winding Y1 and the second primary winding Y2; each secondary winding (F1~FN) includes a first coil X1 and a second coil X2, the first coil X1 corresponds to the first primary winding Y1, and the second coil X2 corresponds to the second primary winding Y2. There is a phase difference between the multiple secondary windings (F1~FN), and there is a phase difference between the first coil X1 and the second coil X2 in each secondary winding (F1~FN).

[0057] Specifically, the phase-shifting transformer 100 is a three-phase transformer. When the phase-shifting transformer 100 is applied to a multi-phase rectifier circuit, refer to... Figure 3As shown, the input terminal of the phase-shifting transformer 100 is connected to the power grid 200. The first primary winding Y1 and the second primary winding Y2 are connected in parallel at the input terminal of the phase-shifting transformer 100. The output terminal of the phase-shifting transformer 100 is connected to the rectifier circuit 300. Three-phase AC power flows from the input terminal of the phase-shifting transformer 100 into the primary windings (including the first primary winding Y1 and the second primary winding Y2), thereby inducing currents in the first coil X1 and the second coil X2 of the multiple secondary windings (F1 to FN). Due to the phase difference between the multiple secondary windings (F1 to FN) and the phase difference within each secondary winding (F1 to FN), There is a phase difference between the first coil X1 and the second coil X2, so these coils will output multi-phase current to the downstream end. When the multi-phase current contains high-order harmonics due to the downstream load, these high-order harmonics can be partially eliminated by phase-shifting superposition when superimposed on the primary winding, thus enabling the phase-shifting transformer to achieve the effect of harmonic suppression. Since the first coil X1 corresponds to the first primary winding Y1, the induced current of the first coil X1 of the multiple secondary windings (F1~FN) will be superimposed on the first primary winding Y1, and correspondingly, the induced current of the second coil X2 will be phase-shifted and superimposed on the second primary winding Y2. Figures 4-5 As shown; secondly, since there is also a phase difference between the first primary winding Y1 and the second primary winding Y2, the current superimposed on these two primary windings will be superimposed again in phase when flowing back to the input terminal of the phase-shifting transformer 100 and into the power grid 200. This further reduces the high-order harmonics in the input current of the phase-shifting transformer 100, giving the phase-shifting transformer better harmonic suppression performance and reducing harmonic interference to the power grid 200. (Reference) Figure 4 and Figure 5 As shown, a Fourier analysis of the input current IAN of the phase-shifting transformer in the related art and the phase-shifting transformer 100 of the present invention clearly shows that the phase-shifting transformer 100 of the present invention has lower high-order harmonics in its input current IAN. Secondly, since the phase-shifting transformer 100 of the present invention has better harmonic suppression performance, it can also reduce the conversion loss of the phase-shifting transformer 100, resulting in a higher PF (power factor) value. Typically, the PF value of the phase-shifting transformer in the related art can reach up to 0.8, while the PF value of the phase-shifting transformer 100 of the present invention can reach up to 0.88, which is significantly better than the related art. In addition, since the phase-shifting transformer 100 has the function of effectively suppressing high-order harmonics at the input, it is easier for the phase-shifting transformer to meet safety regulations and has less interference to other grid-connected equipment, thereby improving the EMC performance (electromagnetic compatibility) of the phase-shifting transformer 100.

[0058] In addition, compared to Figure 1The related technologies shown in this invention, such as the phase-shifting transformer 100, only require changing the winding method of the coil in the secondary winding and adding a primary winding to the primary side of the phase-shifting transformer 100 to achieve the above-mentioned optimization of the harmonic suppression performance of the phase-shifting transformer 100. The increased hardware cost is negligible. In other related technologies, such as Figure 6 The multiphase rectifier circuit shown employs three-phase power factor correction to reduce circuit harmonics, thereby increasing the circuit's power factor (PF) to 0.9 or higher. However, the cost of this circuit is significantly higher than... Figure 1 Compared to the phase-shifting transformer shown, the phase-shifting transformer 100 of this embodiment can achieve the same performance as the phase-shifting transformer in terms of substantially the same hardware cost. Figure 5 The power factor is similar to that of the related technologies shown; therefore, compared to Figure 1 The related technologies shown in this invention enable phase-shifting transformers to achieve better harmonic suppression performance and power factor while maintaining essentially the same hardware cost, compared to... Figure 5 Compared with the related technologies shown, the phase-shifting transformer 100 of the present invention can achieve similar harmonic suppression performance but with lower hardware cost. Therefore, compared with these related technologies, the phase-shifting transformer 100 of the present invention has a higher cost performance.

[0059] In the above embodiments, by setting a first primary winding and a second primary winding with a phase difference on the primary side of the transformer, and correspondingly setting a first coil and a second coil with a phase difference in multiple secondary windings, when the transformer is working normally, the current in the multiple secondary winding coils can be superimposed on the first primary winding and the first primary winding of the primary side in a phase-shifted manner, suppressing the primary current harmonics. At the same time, since the first primary winding and the second primary winding also have a phase difference, the primary current after phase-shifted superposition can be further superimposed in a phase-shifted manner to further suppress the primary current harmonics. This can enhance the harmonic suppression performance of the phase-shifting transformer, thereby improving the EMC performance and conversion efficiency of the phase-shifting transformer, while keeping the hardware cost basically unchanged, improving the cost-effectiveness of the phase-shifting transformer, and realizing the overall optimization of the phase-shifting transformer.

[0060] In some embodiments, the plurality of secondary windings (F1 to FN) include a first secondary winding F1 and at least one pair of second secondary windings (FX, FX+1, N-1≥X≥1), and the phase of one of the second secondary windings FX in each pair of second secondary windings (FX, FX+1) leads the phase of the first secondary winding F1, and the phase of the other second secondary winding FX+1 in each pair of second secondary windings (FX, FX+1) lags the phase of the first secondary winding F1.

[0061] Specifically, the multiple secondary windings (F1 to FN) of the phase-shifting transformer 100 may include a first secondary winding F1 and at least one pair of second secondary windings (FX, FX+1). That is, the number of secondary windings may be an odd number, such as three, five, or seven. The phase angle of each pair of second secondary windings (FX, FX+1) may be such that one leads and the other lags behind the first secondary winding F1. This allows the waveforms of the current superimposed on the primary winding by the induced currents of the multiple secondary windings (F1 to FN) to be complementary, thereby reducing the high-order harmonics in the primary winding. The more second secondary windings (F1 to FN) there are, the better the complementary effect of the waveforms of the multiple superimposed currents, and the stronger the harmonic suppression capability of the phase-shifting transformer 100. Therefore, the number of intermediate and secondary windings (F1 to FN) of the phase-shifting transformer 100 can be flexibly set according to the harmonic suppression requirements of the phase-shifting transformer 100, so as to strengthen the harmonic suppression requirements of the phase-shifting transformer 100 and thus improve the flexibility of the phase-shifting transformer.

[0062] Therefore, by setting a first secondary winding and at least one pair of second secondary windings in the phase-shifting transformer, and making the phase of each pair of second secondary windings one leading and one lagging behind the first secondary winding, the phases of each pair of second secondary windings are symmetrically distributed on both sides of the first secondary winding. This allows the induced current of the secondary windings to achieve complementary current waveforms when superimposed on the primary winding, thereby reducing high-order harmonics. At the same time, the number of secondary windings of the phase-shifting transformer can be flexibly set according to the harmonic suppression requirements of the phase-shifting transformer to strengthen the harmonic suppression requirements of the phase-shifting transformer, thereby improving the flexibility of the phase-shifting transformer.

[0063] Furthermore, the phase of the first secondary winding F1 is determined based on the phases of the first primary winding Y1 and the second primary winding Y2.

[0064] Furthermore, the phase of the first coil X1 in the first secondary winding F1 is the same as the phase of the first primary winding Y1, and the phase of the second coil F2 in the first secondary winding F1 is the same as the phase of the second primary winding Y2.

[0065] Specifically, the phase of the first secondary winding F1 refers to the phase of the first coil X1 in the first secondary winding F1. In order to achieve the complementary effect of multiple superimposed current waveforms, the phase of the first secondary winding F1 can be determined according to the phase of the first primary winding Y1 and the second primary winding Y2. Then, the phase of each pair of second secondary windings (FX, FX+1) can be determined according to the phase of the first secondary winding F1. For example, the phase of the first coil X1 in the first secondary winding F1 can be set to be the same as the phase of the first primary winding Y1, and the phase of the second coil X2 in the first secondary winding F1 can be the same as the phase of the second primary winding Y2. Then, based on the phase angle of the first secondary winding F1, the second secondary winding FX with the leading phase and the second secondary winding FX+1 with the lagging phase in each pair of second secondary windings (FX, FX+1) can be determined. Thus, the phase angle of multiple secondary windings in the phase-shifting transformer can be determined in a simple way.

[0066] In some embodiments, reference Figure 7 As shown, the second primary winding Y2 and the second coil X2 in each secondary winding (F1 to FN) each include at least one, and at least one second primary winding Y2 corresponds one-to-one with at least one second coil X2 in each secondary winding (F1 to FN).

[0067] Specifically, refer to Figure 7 As shown, the number of the second primary winding Y2 and the second coil X2 of each secondary winding (F1 to FN) in the phase-shifting transformer 100 can be one or more, and the two need to correspond one-to-one. That is, for each second primary winding Y2 in the primary winding of the phase-shifting transformer 100, a corresponding second coil X2 needs to be set in each secondary winding (F1 to FN). This way, when the induced current on the second coil X2 of multiple secondary windings (F1 to FN) is superimposed on the corresponding second primary winding Y2, the effect of reducing high-order harmonics can be achieved.

[0068] Furthermore, the phase difference between the first primary winding Y1 and each of the second primary windings Y2 is the same.

[0069] Furthermore, the phase difference between the first primary winding Y1 and each second primary winding Y2 is 30° / n, where n is the number of second primary windings Y2.

[0070] Specifically, the phase difference between the first primary winding Y1 and the second primary winding Y2 in the phase-shifting transformer 100 needs to be designed according to the number of second primary windings Y2. In order to avoid waveform distortion caused by the superposition of the currents of the first primary winding Y1 and the second primary winding Y2 after flowing back to the grid, the phase difference between the first primary winding Y1 and each of the second primary windings Y2 should not be too large, for example, not exceeding 30°. At the same time, the phases of the first primary winding Y1 and each of the second primary windings Y2 can be evenly distributed within a range of 30° so that the effect of reducing high-order harmonics when the first primary winding Y1 and the second primary winding Y2 are superimposed in phase can be optimal.

[0071] For example, refer to Figure 8 As shown, when there is one second primary winding Y2, the phase angle of the first primary winding Y1 is 0°, and the number of second primary windings Y2 can be ±30°; when there are two second primary windings Y2, the phase angles of the two second primary windings Y2 can be +15° and -15° respectively, so as to optimize the harmonic suppression capability of the phase-shifting transformer.

[0072] In some embodiments, the phase difference between the multiple secondary windings is determined based on the number of secondary windings and the number of coils in each secondary winding (F1 to FN).

[0073] Furthermore, the phase difference between the multiple secondary windings (F1-FN) is determined by the following formula (1):

[0074]

[0075] Where δ1 is the phase difference between multiple secondary windings (F1-FN), M is the number of secondary windings, and N is the number of coils.

[0076] Specifically, the phase difference δ1 between multiple secondary windings (F1-FN) refers to the phase difference between two adjacent secondary windings. The phase of the secondary winding is the same as the phase of the first coil X1 inside it. The phases of multiple secondary windings (F1-FN) can be set to a stepped distribution, and the phase difference between two adjacent secondary windings (F1-FN) can be fixed. At the same time, considering that the phase difference between multiple secondary windings (F1-FN) cannot be too large when the phase-shifting transformer is running normally, and that the phase angles of multiple secondary windings (F1-FN) and their internal coils need to be distributed as evenly as possible within a reasonable phase difference range to achieve multi-phase current output, it is necessary to determine the phase difference δ1 between multiple secondary windings based on the number of secondary windings and the number of coils in each secondary winding. For example, the phase difference between multiple secondary windings (F1-FN) can be determined using formula (1) to optimize the harmonic suppression capability of the phase-shifting transformer.

[0077] As a concrete example, see reference Figure 8 As shown, when the phase-shifting transformer 100 includes three secondary windings (F1-F3) and each secondary winding includes two coils, the phase difference between the secondary windings of the phase-shifting transformer 100 can be determined to be 15°. At this time, the phase of the first coil X1 in the three secondary windings (F1~F3) of the phase-shifting transformer 100 can be 0°, +15°, and -15° respectively, thereby optimizing the harmonic suppression capability of the phase-shifting transformer.

[0078] Optionally, the phase difference of the phase-shifting transformer 100 can be adjusted within a reasonable phase difference range; for example, it can be adjusted to... Figure 8 The phase difference between the secondary windings of the phase-shifting transformer 100 shown becomes 20°. The phase of the first coil X1 in the three secondary windings (F1 to F3) of the phase-shifting transformer 100 can be 0°, +20°, and -20° respectively, thereby optimizing the suppression effect on specific frequency harmonics to meet the different harmonic suppression requirements of the phase-shifting transformer and making the phase-shifting transformer more flexible.

[0079] In some embodiments, the phase difference between the first coil X1 and the second coil X2 in each secondary winding is determined based on the number of coils in each secondary winding (F1 to FN).

[0080] Furthermore, the phase difference between the first coil X1 and the second coil X2 in each secondary winding (F1~FN) is determined by the following formula (2):

[0081]

[0082] Where δ2 is the phase difference between the first coil X1 and the second coil X2 in each secondary winding (F1~FN), and N is the number of coils.

[0083] Specifically, since at least one second coil X2 in each secondary winding (F1~FN) needs to correspond one-to-one with at least one second primary winding Y2, and the phase difference between the primary windings of the phase-shifting transformer 100 is a fixed value, the phase difference between the first coil X1 and the second coil X2 in each secondary winding (F1~FN) needs to be a fixed value, and this phase difference needs to be determined based on the number of primary windings. As mentioned above, the number of coils in each secondary winding (F1~FN) of the phase-shifting transformer 100 needs to be equal to the number of second primary windings Y2. Therefore, the number of coils in each secondary winding (F1~FN) can be determined based on the number of coils in each secondary winding (F1~FN). The phase difference between the first coil X1 and the second coil X2 within (1~FN) can be determined, for example, according to the above formula (2), to ensure that the induced current of the second coil X2 can be superimposed on the corresponding second primary winding Y2 when superimposed on the primary current, thereby improving the harmonic suppression effect after superposition. Moreover, when the phase-shifting transformer 100 is used in a multi-phase rectifier circuit, the first coil X1 and the second coil X2 of each secondary winding (F1~FN) share a rectifier circuit, and the phase difference is determined by the above formula (2). Therefore, a 6*N multiple frequency can be output to the filter capacitor of the rectifier circuit at the back end. For example, when N=2, refer to Figure 9 As shown, each secondary winding of the phase-shifting transformer 100 can output a voltage (VBUS1-VBUS3) of 12 times the frequency to the downstream filter capacitor, thereby eliminating the ripple of the downstream filter capacitor, reducing the capacity requirement of the filter capacitor, and optimizing the multiphase rectifier circuit.

[0084] It should be noted that when the phase-shifting transformer 100 of this embodiment is used in a multi-phase rectifier circuit, there is no restriction on the type of rectifier circuit. It can use a commonly used three-phase diode rectifier circuit or other types of rectifier circuits such as a three-phase SCR controlled rectifier. No specific restrictions are imposed here.

[0085] In some embodiments, the number of turns of the first coil X1 in the second secondary winding (FX, FX+1) is determined based on the phase difference between the plurality of first coils X1, the voltage of the first primary winding Y1, the voltage of the first coil X1, and the winding method of the first coil X1.

[0086] Furthermore, the first coil X1 is composed of three-phase windings. When the winding method of the first primary winding Y1 is Y-connected and the winding method of the second coil X2 of the second secondary winding (FX, FX+1) is delta-connected, the number of turns of the first coil X1 in the second secondary winding (FX, FX+1) is determined by the following formula (3):

[0087]

[0088] Wherein, the sum of N2 and N3 is the number of turns of each phase winding of the first coil X1, N3 is used to determine the position of the middle tap of each phase winding, δ3 is the phase difference between multiple first coils X1, VAB is the voltage of the first primary winding Y1, Vab is the voltage of the first coil X1, and N1 is the number of turns of the first primary winding Y1.

[0089] Specifically, since the phase-shifting transformer 100 is a three-phase transformer, the first coil X1 is also usually a three-phase winding. Considering the cost and ease of winding the phase-shifting transformer 100, the first primary winding Y1 of the phase-shifting transformer 100 is usually connected in a Y-type configuration. In this embodiment of the invention, the phase of the first coil X1 in the first secondary winding F1 of the multiple secondary windings (F1~FN) is consistent with the phase of the first primary winding Y1. Therefore, the first coil X1 can also be connected in a Y-type configuration. The first coil X1 in the multiple second secondary windings (FX, FX+1) needs to achieve phase shifts of different angles. Therefore, an extended delta connection is usually used to achieve an adjustable phase shift angle. In this embodiment of the invention, the phase difference δ3 between the plurality of first coils X1 is a vector. The value of the phase difference δ3 represents the phase angle difference between the phase of the first coil X1 of a certain second secondary winding (FX, FX+1) and the phase angle difference between the first coil X1 of the first secondary winding F1. The phase difference δ3 represents the direction of the phase angle difference. When the phase difference δ3 is positive, it indicates that the phase of the first coil X1 of the second secondary winding (FX, FX+1) needs to lead the phase of the first coil X1 of the first secondary winding F1. In this case, it can be used as follows: Figure 10a The positive extended delta connection shown requires a phase difference δ3 of positive value, meaning the phase of the first coil X1 of the second secondary winding (FX, FX+1) needs to lag behind the phase of the first coil X1 of the first secondary winding F1. In this case, the following can be used: Figure 10b The reverse extended delta connection shown is implemented by tapping a single coil into two parts, where N2 is the number of turns in the first part and N3 is the number of turns in the second part. Simultaneously, when determining the number of turns per phase of the first coil X1, the voltage of the first primary winding Y1 and the voltage of the first coil X1 must also be considered to achieve the corresponding boost or buck effect.

[0090] Therefore, to determine the number of turns of the first coil X1 of the phase-shifting transformer 100, the winding method of the first coil X1 can be determined firstly based on the preset phase difference δ3 between multiple first coils X1. Then, the number of turns of the first coil X1 can be determined based on the voltage of the first primary winding Y1, the voltage of the first coil X1, the determined phase difference δ3, and the winding method, so that the first coil X1 can achieve the preset phase shifting and voltage transformation effect.

[0091] For example, the winding method of the first primary winding Y1 is Y-connected, and the winding method of the first coil X1 of the second secondary winding (FX, FX+1) is... Figure 10a When the positive extended delta connection is shown, the phase vector diagram of the first primary winding Y1 and the first coil X1 is as follows: Figure 10a As shown, for Figure 10a Geometric analysis yields the following formula (4).

[0092]

[0093] Where δ is the phase difference between the first primary winding Y1 and the first coil X1, in this embodiment of the invention, since the first coil X1 in the first secondary winding F1 is in phase with the first primary winding Y1, the phase difference δ3 between the first primary winding Y1 and the first coil X1 is the preset phase difference δ3 between the multiple first coils X1. Q V is the voltage value of winding N3 in each phase winding of the first coil X1. by for Figure 11a The voltage values ​​at points b and y are such that, since the amplitude of the voltage in each phase of the three-phase winding is the same, V by =V ax , where V ax for Figure 10b The voltage values ​​at points a and x, and the reference... Figure 10a As shown, V ax This means that the voltage value across the N2+N3 winding is represented. Therefore, after simplifying the above formula (4), the upper part of the above formula (3) can be obtained to determine the tap position of each phase winding of the first coil X1.

[0094] Continue to Figure 11a Geometric analysis yields the following formulas (5) to (6).

[0095]

[0096]

[0097] At the same time, due to V ax =V by And V AX =V AB Therefore, the lower half of the above formula (3) can be obtained according to the above formula (5) to (6). When the number of turns of the first coil X1 is determined according to the above formula (3), the first coil X1 can achieve the preset phase shift and voltage transformation effect.

[0098] It should be noted that when the first coil X1 adopts... Figure 10b When the reverse extended delta connection is shown, the phase vector diagram of the first primary winding Y1 and the first coil X1 is as follows: Figure 11b As shown, since V at this time Q V ax and V ab The triangular relationship remains unchanged; therefore, the above formula (3) can also be applied. Figure 10b The reverse extension triangle connection method shown; additionally, according to Figure 11a and Figure 11b As shown in the phase vector relationship, when the first coil X1 adopts the extended delta connection, the phase shift angle of the first coil X1 in the second secondary winding (F1-FN) based on the first primary winding Y1 varies from -30° to 30°. Since the phase of each secondary winding (F1-FN) is the same as the phase of the first coil X1 inside it, when adjusting the phase difference δ1 between multiple secondary windings (F1-FN) according to the harmonic suppression requirements of the phase shift transformer 100, it is necessary to ensure that the phase shift angle of the first coil X1 in the second secondary winding (FX, FX+1) based on the first primary winding Y1 is within -30° to 30°, so as to avoid the first coil X1 failing to achieve the preset phase shift effect.

[0099] In some embodiments, the number of turns of the second coil X2 in the second secondary winding (FX, FX+1) is determined based on the phase difference between the plurality of second coils X2, the voltage of the second primary winding Y2, the voltage of the second coil X2, and the winding method of the second coil X2.

[0100] Specifically, similar to the considerations for selecting the winding method of the second coil X2 mentioned above, the second primary winding Y2 and the second coil X2 in the first secondary winding F1 of the phase-shifting transformer 100 usually adopt the same connection method, such as a delta connection or an extended delta connection. The specific method needs to be determined according to the phase shift angle. The second coil X2 in multiple secondary windings (FX, FX+1) usually adopts an extended delta connection to achieve an adjustable phase shift angle. Therefore, the winding method of the second coil X2 also needs to be determined based on the phase difference between the multiple second coils X2. Subsequently, based on the voltage of the second primary winding Y2, the voltage of the second coil X2, and the determined phase shift angle and winding method of the second coil X2, the second coil X2 can achieve the preset phase shift and transformation effect.

[0101] Furthermore, the second coil X2 is composed of three-phase windings. When the winding method of the second primary winding Y2 is delta connection and the winding method of the second coil X2 of the second secondary winding (FX, FX+1) is positive extended delta connection, the number of turns of the second coil X2 in the second secondary winding (FX, FX+1) is determined by the following formula (7):

[0102]

[0103] Wherein, the sum of N2' and N3' is the number of turns of each phase winding of the second coil X2, N3' is used to determine the position of the center tap of each phase winding, δ4 is the phase difference between multiple second coils X2, VAB' is the voltage of the second primary winding Y2, Vab' is the voltage of the second coil X2, and N1' is the number of turns of the second primary winding Y2.

[0104] Furthermore, the second coil X2 is composed of three-phase windings. When the winding method of the second primary winding Y2 is delta connection and the winding method of the second coil X2 of the second secondary winding (FX, FX+1) is reverse delta connection, the number of turns of the second coil X2 in the second secondary winding (FX, FX+1) is determined by the following formula (8):

[0105]

[0106] Wherein, the sum of N2' and N3' is the number of turns of each phase winding of the second coil X2, N3' is used to determine the position of the center tap of each phase winding, δ4 is the phase difference between multiple secondary windings (F1~FN), VAB' is the voltage of the second primary winding Y1, Vab' is the voltage of the second coil X2, and N1' is the number of turns of the second primary winding Y2.

[0107] Specifically, the phase difference δ4 between the multiple second coils X2 is a vector, and its specific meaning is the same as that of the multiple off-site coils X1 mentioned above, which will not be repeated here. In this embodiment of the invention, the phase difference δ4 between the multiple second coils X2 represents the phase difference between the second coil X2 in the second secondary winding (FX, FX+1) and the second coil X2 in the first secondary winding F1. When the winding method of the second primary winding Y2 is delta connection, and the phase difference δ4 is between -30° and 0°, the winding method of the second coil X2 in the second secondary winding (FX, FX+1) can be as follows: Figure 10c The positive extended delta connection shown in the diagram has the following phase vector diagrams for the second primary winding Y2 and the second coil X2: Figure 11c As shown, for Figure 11c Geometric analysis reveals that, based on the sine theorem, the above formula (7) can be obtained; similarly, when the phase difference δ4 is between -60° and 30°, the winding method of the second primary winding Y2 is delta connection and the winding method of the second coil X2 of the second secondary winding (FX, FX+1) is... Figure 10d When the reverse extended delta connection is shown, the phase vector diagram of the second primary winding Y2 and the second coil X2 is as follows: Figure 11d As shown, for Figure 11d After performing geometric analysis, the above formula (8) can also be obtained. The specific derivation process is similar to that of formula (3) above, and will not be repeated here.

[0108] It should be noted that, according to Figures 11c-11d As shown in the phase vector relationship, when the second coil X2 adopts a forward-extending delta connection, the phase shift angle of the second coil X2 in the second secondary winding (FX, FX+1) based on the second primary winding Y2 varies from -30° to 0°. When the second coil X2 adopts a reverse-extending delta connection, the phase shift angle of the second coil X2 in the second secondary winding (FX, FX+1) based on the second primary winding Y2 varies from -60° to -30°. Therefore, when adjusting the phase difference δ1 between multiple secondary windings (F1-FN) according to the harmonic suppression requirements of the phase-shifting transformer 100, it is necessary to ensure that the phase shift angle of the second coil X2 in the second secondary winding (FX, FX+1) based on the second primary winding Y2 is within the range of -60° to 0°, so as to avoid the second coil X2 failing to achieve the preset phase shift effect.

[0109] In the above embodiments, the winding method of the multiple first coils and second coils is determined based on the phase difference between the multiple first coils and second coils. Then, the number of turns of the corresponding first coils and second coils is determined according to the above formula, thereby enabling the first coils and second coils to achieve the corresponding phase shifting and voltage transformation effects. At the same time, the number of turns of the multiple first coils is determined based on the first primary winding, and the number of turns of the multiple second coils is determined based on the second primary winding. This allows each coil of the secondary winding to be superimposed on the corresponding primary winding when the high-order harmonic current of the secondary winding is superimposed on the primary winding, thereby enhancing the harmonic suppression capability of the phase shifting transformer.

[0110] In summary, the phase-shifting transformer according to embodiments of the present invention, by setting a first primary winding and a second primary winding with a phase difference on the primary side of the transformer, and correspondingly setting a first coil and a second coil with a phase difference in multiple secondary windings, and determining the number of second coils in multiple secondary windings based on the number of second primary windings, and determining the phase difference between the corresponding multiple coils based on the number of secondary windings and the number of coils in the secondary windings, allows the current in the multiple secondary winding coils to be superimposed on the first primary winding and the first primary winding of the primary side in a phase-shifted manner when the transformer is operating normally, thus suppressing primary current harmonics. Simultaneously, since the first primary winding and the second primary winding also have a phase difference, the primary current after phase-shifted superposition can be further superimposed in a phase-shifted manner to further suppress primary current harmonics. This enhances the harmonic suppression performance of the phase-shifting transformer, improves its conversion efficiency, and maintains essentially the same hardware cost, thereby improving the cost-effectiveness of the phase-shifting transformer and achieving overall optimization of the phase-shifting transformer.

[0111] Corresponding to the above embodiments, this invention also provides a voltage conversion circuit, see reference. Figure 12 As shown, the voltage conversion circuit 1000 includes the aforementioned phase-shifting transformer 100.

[0112] According to the voltage conversion circuit of the present invention, the aforementioned phase-shifting transformer can improve the harmonic suppression performance and conversion efficiency of the voltage conversion circuit, while the hardware cost remains basically unchanged, making the voltage conversion circuit more cost-effective and achieving overall optimization of the voltage conversion circuit.

[0113] Corresponding to the above embodiments, this invention also provides a medical device, see reference. Figure 13 As shown, the medical device 1000 includes the aforementioned phase-shifting transformer 100.

[0114] According to the medical device of the present invention, the aforementioned phase-shifting transformer can improve the harmonic suppression performance and conversion efficiency of the medical device, while the hardware cost remains basically unchanged, making the medical device more cost-effective and achieving overall optimization of the medical device.

[0115] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0116] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0117] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0118] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0119] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0120] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A phase-shifting transformer, characterized in that, include: A first primary winding and a second primary winding are connected in parallel, and there is a phase difference between the first primary winding and the second primary winding. Multiple secondary windings, each of the secondary windings including a first coil and a second coil, the first coil corresponding to the first primary winding, the second coil corresponding to the second primary winding, a phase difference between the multiple secondary windings, and a phase difference between the first coil and the second coil in each secondary winding; The plurality of said secondary windings include a first secondary winding and at least one pair of second secondary windings, wherein the phase of one of the second secondary windings in each pair of second secondary windings leads the phase of the first secondary winding, and the phase of the other second secondary winding in each pair of second secondary windings lags the phase of the first secondary winding. The number of turns of the first coil in the second secondary winding is determined based on the phase difference between multiple first coils, the voltage of the first primary winding, the voltage of the first coil, and the winding method of the first coil. The first coil consists of three-phase windings. When the winding method of the first primary winding is Y-connected and the winding method of the first coil of the second secondary winding is extended delta-connected, the number of turns of the first coil in the second secondary winding is determined in the following way: Wherein, the sum of N2 and N3 is the number of turns in each phase winding of the first coil, and N3 is used to determine the position of the center tap of each phase winding. The phase difference between the multiple first coils is VAB, the voltage of the first primary winding is Vab, the voltage of the first coil is N1, and the number of turns of the first primary winding is N1. or, The number of turns of the second coil in the second secondary winding is determined based on the phase difference between multiple second coils, the voltage of the second primary winding, the voltage of the second coil, and the winding method of the first coil; The second coil consists of three-phase windings. When the primary winding of the second coil is wound in a delta configuration and the secondary winding of the second coil is wound in a forward-extending delta configuration, the number of turns of the second coil in the secondary winding is determined as follows: Wherein, the sum of N2' and N3' is the number of turns in each phase winding of the second coil, and N3' is used to determine the position of the center tap of each phase winding. The phase difference between multiple second coils is given by VAB', the voltage of the second primary winding is given by Vab', the voltage of the second coil is given by N1', and the number of turns of the second primary winding is given by N1. Alternatively, if the second coil is composed of three-phase windings, and the winding method of the second primary winding is delta connection, and the winding method of the second coil of the second secondary winding is reverse delta connection, the number of turns of the second coil in the second secondary winding is determined by the following method: Wherein, the sum of N2' and N3' is the number of turns in each phase winding of the second coil, and N3' is used to determine the position of the center tap of each phase winding. VAB' is the phase difference between multiple second coils, VAB' is the voltage of the second primary winding, Vab' is the voltage of the second coil, and N1' is the number of turns of the second primary winding.

2. The phase-shifting transformer according to claim 1, characterized in that, The phase of the first secondary winding is determined based on the phases of the first primary winding and the second primary winding.

3. The phase-shifting transformer according to claim 2, characterized in that, The phase of the first coil in the first secondary winding is the same as the phase of the first primary winding, and the phase of the second coil in the first secondary winding is the same as the phase of the second primary winding.

4. The phase-shifting transformer according to any one of claims 1-3, characterized in that, The second primary winding and each of the secondary windings each include at least one second coil, and at least one second primary winding corresponds one-to-one with at least one second coil in each of the secondary windings.

5. The phase-shifting transformer according to claim 4, characterized in that, The phase difference between the first primary winding and each of the second primary windings is the same.

6. The phase-shifting transformer according to claim 5, characterized in that, The phase difference between the first primary winding and each of the second primary windings is 30° / n, where n is the number of the second primary windings.

7. The phase-shifting transformer according to claim 4, characterized in that, The phase difference between the multiple secondary windings is determined based on the number of the secondary windings and the number of coils in each secondary winding.

8. The phase-shifting transformer according to claim 7, characterized in that, The phase difference between the multiple secondary windings is determined in the following manner: in, M represents the phase difference between the multiple secondary windings, M represents the number of secondary windings, and N represents the number of coils.

9. The phase-shifting transformer according to claim 4, characterized in that, The phase difference between the first and second coils in each of the secondary windings is determined based on the number of coils in each of the secondary windings.

10. The phase-shifting transformer according to claim 9, characterized in that, The phase difference between the first and second coils in each secondary winding is determined by the following method: in, The phase difference between the first and second coils in each of the secondary windings is N, where N is the number of coils.

11. A voltage conversion circuit, characterized in that, Including the phase-shifting transformer according to any one of claims 1-10.

12. A medical device, characterized in that, Including the phase-shifting transformer according to any one of claims 1-10.

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