Interleaved hysteresis control soft switching power amplifier and hysteresis control method

Abstract

The invention relates to the field of motor drive. The power amplifier based on soft switch control uses a hysteresis + soft switching method to construct upper and lower hysteresis bands respectively using a sine half wave or a sine wave to achieve high dynamic hysteresis current control and soft switching mode. The filter inductor current based on the upper and lower hysteresis bands reduces system loss and enhances system redundancy. The filter inductor is easy to design, which is conducive to reducing the harmonics of the output current. Based on a half-bridge power amplifier with a sine half wave interleaved control with a bias, the hysteresis + interleaved soft switching method uses a sine half wave with a bias to construct upper and lower hysteresis bands respectively, to achieve high dynamic hysteresis current control and soft switching mode. Each loop can be optimized separately, which increases the reliability and flexibility of the system. The problem of unfixed switching frequency, difficult to determine filter inductance, large output current ripple, and failure to meet application requirements is solved.

Description

Technical Field

[0001] The present invention relates to the field of motor driving, and in particular to an interleaved hysteresis control soft switch power amplifier and a hysteresis control method. Background Art

[0002] In the field of motor drive, the current control methods mainly include deadbeat control, sliding film control, hysteresis control, etc. Deadbeat control improves tracking accuracy by calculating the pulse width of the inverter in real time, and the output phase remains basically unchanged, but the system has poor anti-interference ability and stability, is greatly affected by the accuracy of the controlled object and the external environment, has a large overshoot during the transition process, and has high requirements for digital processor performance. Sliding mode control has strong robustness and can better adapt to rapid changes in load, but the sliding mode will be affected by the sampling frequency; the ideal sliding mode surface of sliding mode control is difficult to select and is unstable. Hysteresis current control has the advantages of being fast, reliable, and able to track the reference current in real time, and has been widely used in industrial production.

[0003] Figure 4 It is a traditional half-bridge power amplifier topology and its hysteresis control method. The system reduces losses and improves efficiency. However, its switching frequency is not fixed, the filter inductor is difficult to determine, and the output current ripple is large, which cannot meet the application requirements. Summary of the invention

[0004] The present invention aims to solve the problems that the switching frequency is not fixed, the filter inductance is difficult to determine, the output current ripple is large, and the application requirements cannot be met based on the traditional half-bridge power amplifier topology and its hysteresis control method. An interleaved hysteresis control soft switching power amplifier and a hysteresis control method are provided.

[0005] The technical solution adopted by the present invention is:

[0006] The interleaved hysteresis controlled soft switching power amplifier is a general term for a soft switching controlled power amplifier and a biased sinusoidal half-wave interleaved controlled half-bridge power amplifier. The present invention also includes a hysteresis control method for half-wave or full-wave control of the above two topological structures.

[0007] A soft-switching controlled power amplifier, which is composed of n DC power supplies U dc Power supply, respectively, DC power supply No. 1 U dc1 , No.2 DC power supply U dc2 、No. 3 DC power supply U dc3 , No. 4 DC power supply U dc4 ......nth DC power supply U dcn ,

[0008] The amplifier includes power switch devices S1, S2, S3, S4...S n, resonant capacitors C1, C2, C3, C4...C n , diodes D1, D2, D3, D4...D n , resonant inductors L1, L2, L3...L 1 / 2(n-1) , L 1 / 2n , inductor L, resistor R and capacitor C, n is a natural number;

[0009] Module n: DC power supply U dcn The positive electrode of the power switch device S n The drain of diode D n The cathode and resonant capacitor C n One end of the power switch device S n The source of the diode D n The anode and resonant capacitor C n The other end of the DC power supply U dcn The negative pole is grounded;

[0010] The source of the power switch device S1 is connected to the drain of the power switch device S2 and one end of the inductor L1 at the same time, the source of the power switch device S3 is connected to the drain of the power switch device S4 and one end of the inductor L2 at the same time, and the power switch device S n-1 The source of the power switch device S n The drain and inductance L 1 / 2n One end of

[0011] Inductor L1, L2, L3...L 1 / 2(n-1) , L 1 / 2n The other end of is connected to the other end of the inductor L, one end of the inductor L is connected to one end of the resistor R and one end of the capacitor C, and the other end of the resistor R and the other end of the capacitor C are grounded.

[0012] A full-wave hysteresis control method for a power amplifier based on soft switching control, the method comprising the following steps:

[0013] Step 1: The control method is completed by a hysteresis control module;

[0014] Step 2: The hysteresis control module uses a hysteresis controller to set the hysteresis band to a double sine hysteresis band, wherein the double sine hysteresis band includes an upper hysteresis band and a lower hysteresis band;

[0015] Step 3: The upper hysteresis band is composed of switch devices S1, S3...S b ...S n-3 Control, the lower hysteresis band is controlled by the switching devices S2, S4...S c ...S nControl, where b is n%2=1; c is n%2=0, n%2 represents the remainder after n is divided by 2; Step 4, the upper hysteresis band is set to The lower hysteresis band is set to

[0016] Where: i th is the bias current, i th The setting is to meet the working conditions of soft switching;

[0017] i up is the upper hysteresis band; i out is a given current; i low It is the lower hysteresis zone;

[0018] Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

[0019] A half-bridge power amplifier with sinusoidal half-wave interleaved control with bias, which is composed of n / 2 DC power supplies U dc Power supply, respectively, DC power supply No. 1 U dc1 , No.2 DC power supply U dc2 , No. 3 DC power supply U dc3 , No. 4 DC power supply U dc4 ......n / 2 DC power supply U dc1 / 2n ,

[0020] The amplifier includes power switch devices S1, S2, S3, S4...S n , resonant capacitors C1, C2, C3, C4...C n , diodes D1, D2, D3, D4...D n , resonant inductors L1, L2, L3...L n / 2 , inductor L, resistor R and capacitor C, n is a natural number;

[0021] No. 1 DC power supply U dc1 The positive electrode is connected to the drain of the power switch devices S1 and S3, the drain of the power switch device S1 is connected to the cathode of the diode D1 and one end of the resonant capacitor C1, the source of the power switch device S1 is connected to the anode of the diode D1 and the other end of the resonant capacitor C1; the drain of the power switch device S3 is connected to the cathode of the diode D3 and one end of the resonant capacitor C3, the source of the power switch device S3 is connected to the anode of the diode D3 and the other end of the resonant capacitor C3; DC power supply No. 1 U dc1 The negative pole is grounded;

[0022] No.2 DC power supply U dc2The positive electrode is connected to the drain of power switch devices S2 and S4, the drain of power switch device S2 is connected to the cathode of diode D2 and one end of resonant capacitor C2, the source of power switch device S2 is connected to the anode of diode D2 and the other end of resonant capacitor C2; the drain of power switch device S4 is connected to the cathode of diode D4 and one end of resonant capacitor C4, the source of power switch device S4 is connected to the anode of diode D4 and the other end of resonant capacitor C4; No. 2 DC power supply U dc2 The negative pole is grounded;

[0023] Module n: (n-1) / 2 DC power supply U dc(n-1) / 2 The positive pole of the power switch device S n-1 and S n-3 The drain of the power switch device S n-1 The drain of the diode D n-1 The cathode and resonant capacitor C n-1 One end of the power switch device S n-1 The source of the diode D n-1 The anode and resonant capacitor C n-1 The other end of the power switch device S n-3 The drain of the diode D n-3 The cathode and resonant capacitor C n-3 One end of the power switch device S n-3 The source of the diode D n-3 The anode and resonant capacitor C n-3 The other end; (n-1) / 2 DC power supply U dc(n-1) / 2 The negative pole is grounded;

[0024] n / 2 DC power supply U dc1 / 2n The positive pole of the power switch device S n and S n-2 The drain of the power switch device S n The drain of the diode D n The cathode and resonant capacitor C n One end of the power switch device S n The source of the diode D n The anode and resonant capacitor C n The other end of the power switch device S n-2 The drain of the diode D n-2 The cathode and resonant capacitor C n-2 One end of the power switch device S n-2 The source of the diode D n-2 The anode and resonant capacitor C n-2 The other end; n / 2 DC power supply U dc1 / 2nThe negative electrode of the power switch device S1 is connected to the ground; the source of the power switch device S1 is connected to the drain of the power switch device S2 and one end of the inductor L1 at the same time, the source of the power switch device S3 is connected to the drain of the power switch device S4 and one end of the inductor L2 at the same time, the drain of the power switch device S1 is connected to the drain of the power switch device S3 at the same time, the source of the power switch device S2 is connected to the source of the power switch device S4 at the same time, and so on. n-1 The source of the power switch device S n The drain and inductance L 1 / 2n One end of the power switch device S n-3 The source of the power switch device S n-2 The drain and inductance L 1 / 2(n-1) One end of the power switch device S n-1 The drain of the power switch device S n-3 The drain of the power switch device S n The source of the power switch device S n-2 The source of

[0025] Inductor L1, L2, L3.......L n / 2 The other end of the resistor R is connected to the other end of the inductor L, one end of the inductor L is connected to one end of the resistor R and one end of the capacitor C, and the other end of the resistor R and the other end of the capacitor C are grounded. ".

[0026] A hysteresis control method for a half-bridge power amplifier based on a sinusoidal half-wave interleaved control with bias, the method comprising the following steps:

[0027] Step 1: The control method is completed by a hysteresis control module;

[0028] Step 2: The hysteresis control module adopts four hysteresis controllers, and the hysteresis band is divided into four hysteresis bands to stagger the switching device to conduct; the four hysteresis bands are an upper hysteresis band of a positive half-wave, a lower hysteresis band of a positive half-wave, an upper hysteresis band of a negative half-wave, and a lower hysteresis band of a negative half-wave; the upper hysteresis band of a positive half-wave and the lower hysteresis band of a positive half-wave constitute the hysteresis band of a positive half-wave, and the upper hysteresis band of a negative half-wave and the lower hysteresis band of a negative half-wave constitute the hysteresis band of a negative half-wave;

[0029] Step 3: The hysteresis band of the positive half-wave is composed of S1, S 2... S x1... S n-7 , S n-6 and S3, S 4... S x2... S n-5 , S n-4 control; the hysteresis band of the negative half-wave is respectively composed of S8, S 7... S y1... S n , Sn-1 and S6, S 5... S y2... S n-2 , S n-3 Control, where x1 is n%8=1 or n%8=2; x2 is n%8=3 or n%8=4, y1 is n%8=5 or n%8=6; y2 is n%8=7 or n%8=0, n%8 represents the remainder after n is divided by 8;

[0030] Step 4: Set the hysteresis band of the positive half-wave as shown in equation (3) and equation (4), and set the hysteresis band of the negative half-wave as shown in equation (5) and equation (6):

[0031]

[0032] Among them, i set To set the current, i set The setting is to make the switching frequency relatively fixed, i th The setting is to meet the working conditions of soft switching; i up is the upper hysteresis band; i out is a given current; i low is the lower hysteresis band; |i out| is the absolute value of the given current;

[0033] Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

[0034] The power switch device adopts MOSFET, GTR or IGBT with reverse parallel body diode.

[0035] Beneficial effects: The present invention provides a soft-switch controlled power amplifier, a half-bridge hysteresis control method for a soft-switch controlled power amplifier (first scheme), a full-wave hysteresis control method for a soft-switch controlled power amplifier (second scheme), a biased sinusoidal half-wave interleaved controlled half-bridge power amplifier, and a hysteresis control method for a biased sinusoidal half-wave interleaved controlled half-bridge power amplifier (third scheme), with two topologies and three control methods in total, which can be summarized as an interleaved hysteresis controlled soft-switch power amplifier and a hysteresis control method.

[0036] Taking the sinusoidal drive current as an example, the first solution is based on a power amplifier controlled by a soft switch. This is a sinusoidal half-wave controlled half-bridge power amplifier topology. Through the hysteresis + soft switch control method, the upper and lower hysteresis bands are constructed using sinusoidal half waves to achieve high-dynamic hysteresis current control and soft switch mode. The upper and lower sinusoidal half-wave filtered inductor currents are conducive to further reducing system losses and enhancing system redundancy. In addition, the control method of N-way module parallel connection can also be expanded.

[0037] The second solution is based on a power amplifier controlled by a soft switch. This is a sine wave controlled half-bridge power amplifier topology. Through the hysteresis + soft switch control method, a biased sine (full) wave is used to construct the upper and lower hysteresis bands respectively to achieve high dynamic hysteresis current control and soft switch mode, making the filter inductor easy to design and conducive to reducing the harmonics of the output current. In addition, the control method of N-way module parallel connection can also be expanded.

[0038] The third solution is based on the half-bridge power amplifier topology with biased sinusoidal half-wave interleaved control. Through the hysteresis + interleaved soft switching control method, the upper and lower hysteresis bands are constructed respectively with biased sinusoidal half-waves to achieve high-dynamic hysteresis current control and soft switching mode. Each loop can be optimized separately, increasing the reliability and flexibility of the system. In addition, the control method of N-way module parallel connection can also be expanded.

[0039] The present invention uses a power amplifier based on soft switching control and hysteresis control as the main framework, which solves the problems of the traditional half-bridge power amplifier topology and its hysteresis control method, such as the unstable switching frequency, difficult to determine the filter inductor, large output current ripple, and inability to meet application requirements. It also solves the problems of the traditional hysteresis control circuit, such as the difficulty in designing the filter inductor, poor flexibility, high output harmonics, and unstable switching frequency.

[0040] By staggering the switching, the hysteresis band ( Figure 8 ) is separated so that the switching frequency is relatively fixed. The filter inductance is related to the frequency, so the filter inductance can be determined. The method of the present invention achieves the purpose of reducing the output ripple through multi-phase output, meeting the application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic diagram of a power amplifier controlled by soft switching when n is 4;

[0042] Figure 2 is a schematic diagram of a power amplifier controlled by soft switching;

[0043] Figure 3 is a schematic diagram of an inductor current waveform and an output current waveform of the method described in Implementation Mode 2;

[0044] Figure 4 It is a schematic diagram of a conventional half-bridge based power amplifier topology and its control method;

[0045] Figure 5 is a schematic diagram of an inductor current waveform and an output current waveform of the method described in Implementation Mode 3;

[0046] Figure 6 is a schematic diagram of a half-bridge power amplifier with a biased sinusoidal half-wave interleaved control when n is 8 in the fourth implementation mode;

[0047] Figure 7 is a schematic diagram of a half-bridge power amplifier with sinusoidal half-wave interleaved control with bias;

[0048] Figure 8 is a schematic diagram of an inductor current waveform of the method described in Embodiment 5;

[0049] Fig. 9 is a schematic diagram of an output current waveform of the method described in Embodiment 5;

[0050] Fig.10 Schematic diagram of various electrical states of a half bridge in one switching cycle in implementation modes four and five;

[0051] Fig.11 It is a schematic diagram of the current flow from t1 to t2;

[0052] Fig.12 , Fig.13 It is a schematic diagram of the current flow from t2 to t3;

[0053] Fig.14 It is a schematic diagram of the current flow at time t3-t4;

[0054] Fig.15 It is a schematic diagram of the current flow at time t4-t5;

[0055] Fig.16 , Fig.17 This is a schematic diagram of the current flow at t5-t6;

[0056] Fig.18 This is a schematic diagram of the current flow at t6~t1'. DETAILED DESCRIPTION

[0057] Specific implementation method 1. Reference Figures 1 to 2 Specifically describe this embodiment, the power amplifier controlled by the soft switch in this embodiment is composed of n DC power supplies U dc Power supply, respectively, DC power supply No. 1 U dc1 , No.2 DC power supply U dc2 , No. 3 DC power supply U dc3 , No. 4 DC power supply U dc4......nth DC power supply U dcn ,

[0058] The amplifier includes power switch devices S1, S2, S3, S4...S n , resonant capacitors C1, C2, C3, C4...C n , diodes D1, D2, D3, D4...D n , resonant inductors L1, L2, L3...L n , inductor L, resistor R and capacitor C;

[0059] Module n: DC power supply U dcn The positive electrode of the power switch device S n The drain of diode D n The cathode and resonant capacitor C n One end of the power switch device S n The source of the diode D n The anode and resonant capacitor C n The other end of the DC power supply U dcn The negative pole is grounded;

[0060] The source of the power switch device S1 is connected to the drain of the power switch device S2 and one end of the inductor L1 at the same time, the source of the power switch device S3 is connected to the drain of the power switch device S4 and one end of the inductor L2 at the same time, and the power switch device S n-1 The source of the power switch device S n The drain and inductance L n One end of

[0061] Inductor L1, L2, L3...L n The other end of is connected to the other end of the inductor L, one end of the inductor L is connected to one end of the resistor R and one end of the capacitor C, and the other end of the resistor R and the other end of the capacitor C are grounded.

[0062] Specific implementation method II. Reference Figures 1 to 16 Specifically describing this embodiment, based on the half-wave hysteresis control method of the power amplifier controlled by the soft switch described in the first embodiment, the method comprises the following steps:

[0063] Step 1: The control method is completed by a hysteresis control module;

[0064] Step 2, the hysteresis control module includes two hysteresis controllers, and the two hysteresis controllers divide the hysteresis band into a positive half-wave hysteresis band and a negative half-wave hysteresis band;

[0065] Step 3: The positive half-wave hysteresis band is composed of switching devices S1, S2...Sn-3 , S n-2 Control, the negative half-wave hysteresis band is controlled by the switching devices S3, S4...S n-1 , S n control;

[0066] Step 4: Set the hysteresis band of the positive half-wave as shown in formula (1), and set the hysteresis band of the negative half-wave as shown in formula (2):

[0067]

[0068] Where: i th is the bias current, i th The setting is to meet the working conditions of soft switching;

[0069] i up is the upper hysteresis band; i out is a given current; i low is the lower hysteresis band; |i out| is the absolute value of the given current;

[0070] Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

[0071] In implementation modes 1 and 2 (Scheme 1), the soft-switching controlled power amplifier (sine half-wave controlled half-bridge power amplifier topology) is powered by a DC power supply and consists of two half-bridge inverters, a resonant circuit, and an output LC circuit. The power switch device uses a MOSFET, GTR or IGBT with an anti-parallel body diode. Figure 2 shown.

[0072] Figure 1 for Figure 2 part of Figure 1 In the figure, the half-bridge inverter consists of power switch devices S1, S2, S3, S4 and resonant capacitors C1, C2, C3, C4. The resonant circuit consists of power switch devices S1, S2 and resonant inductor L1, and S3, S4 and resonant inductor L2. The output LC circuit consists of inductor L3 and capacitor C3.

[0073] The hysteresis control part uses two hysteresis controllers to divide the hysteresis band into only positive half-wave and only negative half-wave. Figure 1 and 2 shown. Figure 1 In which the positive half-wave is controlled by S1 and S2, and the negative half-wave is controlled by S3 and S4. The hysteresis band of the positive half-wave is set as shown in formula (1), and the hysteresis band of the negative half-wave is set as shown in formula (2), where i th The setting is to meet the working conditions of soft switching. In addition, N modules are connected in parallel as Figure 2 As shown, the reliability and stability of the circuit are increased by superimposing multiple control outputs, and the ripple of the output voltage and current is reduced.

[0074]

[0075] In this embodiment, when n is 4, the power amplifier controlled by the soft switch is as follows: Figure 1 As shown, the soft-switching controlled power amplifier (half-wave sine-controlled half-bridge power amplifier topology) is powered by a DC power supply and consists of two half-bridges, a resonant circuit, and an output LC circuit. The power switch device is a MOSFET, GTR, or IGBT with an anti-parallel body diode.

[0076] Specific implementation method 3, reference Figures 1 to 5 Specifically describing this embodiment, based on the full-wave hysteresis control method of the power amplifier controlled by the soft switch described in the first embodiment, the method comprises the following steps:

[0077] Step 1: The control method is completed by a hysteresis control module;

[0078] Step 2: The hysteresis control module uses a hysteresis controller to set the hysteresis band to a double sine hysteresis band, wherein the double sine hysteresis band includes an upper hysteresis band and a lower hysteresis band;

[0079] Step 3: The upper hysteresis band is composed of switch devices S1, S3...S n-3 Control, the lower hysteresis band is controlled by the switch devices S2, S4...S n control;

[0080] Step 4: Set the upper hysteresis band to The lower hysteresis band is set to

[0081] Where: i th is the bias current, i th The setting is to meet the working conditions of soft switching;

[0082] i up is the upper hysteresis band; i out is a given current;

[0083] Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

[0084] In this implementation (Scheme 2), the soft switch controlled power amplifier (i.e., half-sine wave controlled half-bridge power amplifier) ​​when n is 4 is powered by a DC power supply and is composed of two half-bridges, a resonant circuit, and an output LC circuit. The power switch device is a MOSFET, GTR, or IGBT with an anti-parallel body diode.

[0085] The half-bridge inverter consists of power switch devices S1, S2, S3, S4 and resonant capacitors C1, C2, C3, C4. The resonant circuit consists of power switch devices S1, S2 and resonant inductor L1, S3, S4 and resonant inductor L2. The output LC circuit consists of inductor L and capacitor C.

[0086] The hysteresis control part uses a hysteresis controller to set the hysteresis band to double sine, such as Figure 5 As shown. The upper hysteresis band is controlled by S1, and the lower hysteresis band is controlled by S2. Set the upper hysteresis band to The lower hysteresis band is set to where i th The setting is to meet the working conditions of soft switching. In addition, N modules are connected in parallel as follows Figure 2 As shown, the reliability and stability of the circuit are increased by superimposing multiple control outputs. At the same time, there is no magnetic bias, electromagnetic interference is reduced, and the switching frequency is distributed more evenly, avoiding excessive noise in a specific frequency band.

[0087] The second solution is a soft-switching controlled power amplifier and its full-wave hysteresis control method (i.e., a sine half-wave controlled half-bridge power amplifier topology). Through the hysteresis + soft-switching control method, a biased sine wave is used to construct the upper and lower hysteresis bands respectively to achieve high-dynamic hysteresis current control and soft-switching mode, making the filter inductor easy to design and conducive to reducing the harmonics of the output current. In addition, the control method of N-way parallel modules can also be expanded.

[0088] Specific implementation method 4. Reference Figures 6 to 9 Specifically describe this embodiment, the half-bridge power amplifier with biased sinusoidal half-wave interleaved control described in this embodiment is composed of n DC power supplies U dc Power supply, respectively, DC power supply No. 1 U dc1 , No.2 DC power supply U dc2 、No. 3 DC power supply U dc3 , No. 4 DC power supply U dc4 ......nth DC power supply U dcn ,

[0089] The amplifier includes power switch devices S1, S2, S3, S4...S n , resonant capacitors C1, C2, C3, C4...C n, diodes D1, D2, D3, D4...D n , resonant inductors L1, L2, L3...L n , inductor L, resistor R and capacitor C;

[0090] Module n: DC power supply U dcn The positive electrode of the power switch device S n The drain of diode D n The cathode and resonant capacitor C n One end of the power switch device S n The source of the diode D n The anode and resonant capacitor C n The other end of the DC power supply U dcn The negative pole is grounded;

[0091] The source of the power switch device S1 is connected to the drain of the power switch device S2 and one end of the inductor L1 at the same time, the source of the power switch device S3 is connected to the drain of the power switch device S4 and one end of the inductor L2 at the same time, the drain of the power switch device S3 is connected to the drain of the power switch device S3 at the same time, the source of the power switch device S2 is connected to the source of the power switch device S4 at the same time, and so on, ... the power switch device S n-1 The source of the power switch device S n The drain and inductance L n One end of the power switch device S n-1 The source of the power switch device S n The drain and inductance L 1 / 2n One end of the power switch device S n-3 The source of the power switch device S n-2 The drain and inductance L 1 / 2(n-1) One end of the power switch device S n-1 The drain of the power switch device S n-3 The drain of the power switch device S n The source of the power switch device S n-2 The source of

[0092] Inductor L1, L2, L3...L 1 / 2(n-1) The other end of is connected to the other end of the inductor L, one end of the inductor L is connected to one end of the resistor R and one end of the capacitor C, and the other end of the resistor R and the other end of the capacitor C are grounded.

[0093] Specific implementation method 5. Reference Figures 6 to 9 Specifically describing this embodiment, based on the hysteresis control method of the half-bridge power amplifier with biased sinusoidal half-wave interleaved control described in Embodiment 4, the method comprises the following steps:

[0094] Step 1: The control method is completed by a hysteresis control module;

[0095] Step 2: The hysteresis control module uses four hysteresis controllers, and the hysteresis band is divided into four hysteresis bands to control the switching devices to be turned on in an interlaced manner;

[0096] Step 3: The hysteresis band of the positive half-wave is respectively composed of S1, S2...S n-7 , S n-6 and S3, S4...S n-5 , S n-4 Control; the hysteresis band of the negative half-wave is respectively composed of S8, S7...S n , S n-1 and S6, S5...S n-2 , S n-3 control;

[0097] Step 4: Set the hysteresis band of the positive half-wave as shown in equation (3) and equation (4), and set the hysteresis band of the negative half-wave as shown in equation (5) and equation (6):

[0098]

[0099] Among them, i set To set the current, i set The setting is to make the switching frequency relatively fixed, i th The setting is to meet the working conditions of soft switching; i up is the upper hysteresis band; i out is a given current; i low is the lower hysteresis band; |i out| is the absolute value of the given current;

[0100] Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

[0101] Implementation methods 4 and 5 are the third solution, based on the half-bridge power amplifier topology controlled by half-wave interleaved control with bias, and the control method of hysteresis + interleaved soft switching, using half-wave sine with bias to construct upper and lower hysteresis bands respectively, to achieve high dynamic hysteresis current control and soft switching mode, each loop can be optimized separately, increasing the reliability and flexibility of the system. In addition, the control method of N-way module parallel connection can also be expanded.

[0102] Specific implementation method 6: This implementation method is a further explanation of implementation method 1 or 4. The power switch device adopts MOSFET, GTR or IGBT with an anti-parallel body diode.

[0103] The hysteresis band is generated by setting and can be obtained through the formula.

[0104] The process of the control method is: first use a formula to set the shape of the hysteresis band, then compare the inductor current with the hysteresis band, and send the comparison result to the hysteresis comparator to control the on and off of the power switch device.

[0105] Figure 6 In the example, n=8, the half-bridge power amplifier with half-wave interleaved control with bias is Figure 6 As shown, it is powered by a DC power supply and consists of two half bridges, a resonant circuit, and an output LC circuit.

[0106] The half-bridge inverter is composed of power switch devices S1, S2, S3, S4, S5, S6, S7, S8 and resonant capacitors C1, C2, C3, C4, C5, C6, C7, C8. The resonant circuit is composed of power switch devices S1, S2 and resonant inductor L1, S3, S4 and resonant inductor L2, S5, S6 and resonant inductor L3, S7, S8 and resonant inductor L4. The output LC circuit is composed of inductor L and capacitor C.

[0107] The hysteresis control part uses four hysteresis controllers to divide the hysteresis band into four hysteresis bands and stagger the switching devices to conduct. Figure 8 As shown. The hysteresis band of the positive half-wave is controlled by S1, S2 and S3, S4 respectively. The hysteresis band of the negative half-wave is controlled by S5, S6 and S7, S8 respectively. The hysteresis band of the positive half-wave is set as shown in formula (3) and as shown in formula (4), and the hysteresis band of the negative half-wave is set as shown in formula (5) and as shown in formula (6), where i set The setting is to make the switching frequency relatively fixed, i th The setting is to meet the working conditions of soft switching. In addition, N modules are connected in parallel as Figure 7 As shown in the figure, the circuit stability is increased by superimposing multiple control loop outputs. At the same time, the frequency distribution of the module is more uniform, and the filter inductor is easy to design, which is conducive to reducing the harmonics of the output current. In addition, each loop can be optimized and designed separately, which increases the flexibility and reliability of the system.

[0108]

[0109]

[0110] Solution 3: Working principle of half-bridge power amplifier with half-wave interleaved control with bias ( Figure 11-18 ):

[0111] The upper boundary of this strategy is the reference current iref plus the bandwidth ΔI; the lower boundary is the reference current iref minus the bandwidth ΔI. By staggered switch conduction, the inductor currents iL1, iL2, iL3, and iL4 are compared with the upper and lower boundaries respectively. Taking switches S1 and S2 as examples, when iL1 exceeds the upper boundary, a set of control signals is obtained, so that the switch tube S1 is turned off, S2 is turned on, and the inductor current decreases; when iL1 is less than the lower boundary, another set of control signals is obtained, so that the switch tube S1 is turned on, S2 is turned off, and the inductor current increases. In other cases, the states of switches S1 and S2 do not change. Similarly, other hysteresis controllers and other solutions work in the same way.

[0112] The electrical states of a half-bridge in a switching cycle are as follows: Fig.10 As shown, V S1 is the driving signal on the switch tube S1, V S2 is the driving signal on the switch tube S2, S Q1 Indicates the on / off state of the switch tube S1, S Q2 Indicates the on / off state of the switch tube S2, V ds1 Represents the voltage across the switch tube S1, V ds2 Indicates the voltage across the switch tube S2, i L is the current value on the inductor. Assume that the upper boundary of the inductor current is i up , the lower boundary is i low Taking one of the half bridges of Scheme 3 as an example, the analysis method of the remaining half bridges is the same as it is, and the analysis methods of other schemes are similar.

[0113] During the time period from t1 to t2, V S1 A high level pulse is sent out, the switch tube S1 is turned on, V S2 A low level pulse is sent out, and the switch tube S2 is turned off. DC Provide energy to the load. Since the inductor L has a certain resistance to the changing current, the current i flowing through the inductor L L It will slowly increase and reach the upper boundary at time t2. The voltage polarity across the inductor L is positive on the left and negative on the right. At this time, the voltage V across the switch tube S1 is ds1 The value of is zero, and the voltage V across the switch tube Q2 ds2 The value is equal to U DC The current flows as follows Fig.11 shown.

[0114] During the time period from t2 to t3, since the inductor current reaches the upper boundary at time t2, V S1 Send out a low level pulse, V S2 A high level pulse is sent, and the switch tube S1 is turned off. At this time, the parallel capacitor C2 of the switch tube S2 is discharged, and the parallel capacitor C1 of the switch tube S1 is charged. The voltage V ds1The value of the switch tube S2 increases, and the voltage V ds2 The value of is reduced, and the current flows as Fig.12 When the voltage across S2 drops to zero, the freewheeling diode D2 starts to conduct, and the current flows as shown in Fig.13 shown.

[0115] During the time period from t3 to t4, the DC power supply U DC Provides energy to the load, at this time V S1 Send out a low level pulse, V S2 A high level pulse is emitted. At t3, the parallel capacitor C2 of the switch tube S2 is completely discharged. At this time, the voltage V ds1 The value is equal to U DC , the voltage across the switch tube S2 is V ds2 The value of drops to zero, and the switch tube S2 is turned on under zero voltage. The inductor L still generates an electromotive force that is positive on the left and negative on the right. The direction of the inductor current is still from left to right, but the current decreases as the electromotive force on the inductor L decreases. At time t4, the current i on the inductor L is L becomes 0, such as Fig.14 shown.

[0116] During the time period from t4 to t5, the current i flowing through the inductor L is L The current direction is opposite to that during t1 to t4. S1 Send out a low level pulse, V S2 A high level pulse is sent, the switch tube S1 is turned off, and the switch tube S2 is turned on. Since the inductor L has a certain resistance to the changing current, the current i flowing through the inductor L L The value will increase slowly. The voltage polarity of the two ends of the inductor L is negative on the left and positive on the right. The current flow direction at t3~t5 is as follows Fig.15 shown.

[0117] During the time period from t5 to t6, since the inductor current reaches the lower boundary at t5, V S1 Send out a high level pulse, V S2 A low level pulse is sent, and the switch tube S2 is turned off. At this time, the parallel capacitor C1 of the switch tube S1 is discharged, and the parallel capacitor C2 of the switch tube S2 is charged. The voltage V ds2 The value of the switch tube S1 increases, and the voltage V ds1 The current flows as Fig.16 When the voltage across S1 drops to zero, the freewheeling diode D1 starts to conduct, and the current flows as shown in Fig.17 shown.

[0118] During the time period from t6 to t1', the upper DC power supply U DCProvide energy to the load. At t6, the parallel capacitor C1 of the switch tube S1 is completely discharged. At this time, the voltage V ds2 The value is equal to U DC , the voltage across the switch tube S1 is V ds1 The value of drops to zero, and the switch tube S1 is turned on under zero voltage environment. The inductor L still generates an electromotive force with negative on the left and positive on the right. The direction of the inductor current is still from right to left, but the current decreases as the electromotive force on the inductor L decreases. At time t1', the current i on the inductor L is L becomes 0. The current flows as Fig.18 shown.

[0119] The topological combination and method of the present invention, combined with the hysteresis control method Figure 5 , Figure 8 , Fig. 9 It can be known that this method solves the problem of non-fixed switching frequency based on the traditional half-bridge power amplifier topology and its hysteresis control method, and the present invention provides a method for optimizing the filter inductor, which reduces the output current ripple, so that the topology and hysteresis control method of the present invention meet the requirements of field applications.

[0120] The present invention is described by several specific embodiments, and it should be understood by those skilled in the art that various changes and equivalent substitutions may be made to the present invention without departing from the scope of the present invention. In addition, various modifications may be made to the present invention for specific situations or specific circumstances without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed, but should include all implementation methods falling within the scope of the claims of the present invention.

Claims

1. Half-wave hysteresis control method of power amplifier based on soft switching control, A soft-switching controlled power amplifier, which is composed of n DC power supplies U dc Power supply, respectively, DC power supply No. 1 U dc1 , No.2 DC power supply U dc2 、No. 3 DC power supply U dc3 , No. 4 DC power supply U dc4 ......nth DC power supply U dcn , The amplifier includes power switch devices S1, S2, S3, S4...S n , resonant capacitors C1, C2, C3, C4...C n , diodes D1, D2, D3, D4...D n , resonant inductor L1, L2, L3.......L 1 / 2(n-1) , L 1 / 2n , inductor L, resistor R and capacitor C, n is a natural number; Module n: DC power supply U dcn The positive pole of the power switch device S is grounded. n The drain of the diode D n The cathode and resonant capacitor C n One end of the inductor L 1 / 2n One end of the power switch device S n-1 The source of diode D n-1 The anode and resonant capacitor C n-1 The other end of the power switch device S n The source of is connected to the DC power supply U dcn The cathode of diode D n The anode and resonant capacitor C n The other end of the power switch device S n-1 The drain of the diode D n-1 The cathode and resonant capacitor C n-1 One end and DC power supply U dcn-1 The positive pole of the DC power supply U dcn-1 The negative pole is grounded; The source of the power switch device S1 is connected to the drain of the power switch device S2 and one end of the inductor L1 at the same time, the source of the power switch device S3 is connected to the drain of the power switch device S4 and one end of the inductor L2 at the same time, and the power switch device S n-1 The source of the power switch device S n The drain and inductance L 1 / 2n One end of Inductor L1, L2, L3.....L 1 / 2(n-1) , L 1 / 2n The other end of is connected to the other end of the inductor L, one end of the inductor L is connected to one end of the resistor R and one end of the capacitor C, and the other end of the resistor R and the other end of the capacitor C are grounded; The power switch device adopts MOSFET, GTR or IGBT with reverse parallel body diode; It is characterized in that The method comprises the following steps: Step 1: The control method is completed by a hysteresis control module; Step 2, the hysteresis control module includes two hysteresis controllers, and the two hysteresis controllers divide the hysteresis band into a positive half-wave hysteresis band and a negative half-wave hysteresis band; Step 3: The positive half-wave hysteresis band is composed of switching devices S1, S2...S i ...S n-3 , S n-2 Control, the negative half-wave hysteresis band is controlled by the switching devices S3, S4...S j ...S n-1 , S n Control, where i is n%4=1 or n%4=2; j is n%4=3 or n%4=0, and n%4 represents the remainder after n is divided by 4; Step 4: Set the hysteresis band of the positive half-wave as shown in formula (1), and set the hysteresis band of the negative half-wave as shown in formula (2): Where: i th is the bias current, i th The setting is to meet the working conditions of soft switching; i up is the upper hysteresis band; i out is a given current; i low is the lower hysteresis band; |i out| is the absolute value of the given current; Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

2. Hysteresis control method of half-bridge power amplifier based on half-wave interleaved control with bias, A half-bridge power amplifier with sinusoidal half-wave interleaved control with bias, which is composed of n / 2 DC power supplies U dc Power supply, respectively, DC power supply No. 1 U dc1 , No.2 DC power supply U dc2 、No. 3 DC power supply U dc3 , No. 4 DC power supply U dc4 ......n / 2 DC power supply U dc1 / 2n , The amplifier includes power switch devices S1, S2, S3, S4...S n , resonant capacitors C1, C2, C3, C4...C n , diodes D1, D2, D3, D4...D n , resonant inductors L1, L2, L3...L n / 2 , inductor L, resistor R and capacitor C, n is a natural number; No. 1 DC power supply U dc1 The positive electrode is connected to the drain of the power switch devices S1 and S3, the drain of the power switch device S1 is connected to the cathode of the diode D1 and one end of the resonant capacitor C1, the source of the power switch device S1 is connected to the anode of the diode D1 and the other end of the resonant capacitor C1; the drain of the power switch device S3 is connected to the cathode of the diode D3 and one end of the resonant capacitor C3, the source of the power switch device S3 is connected to the anode of the diode D3 and the other end of the resonant capacitor C3; DC power supply No. 1 U dc1 The negative pole is grounded; No.2 DC power supply U dc2 The positive electrode is connected to the drain of power switch devices S2 and S4, the drain of power switch device S2 is connected to the cathode of diode D2 and one end of resonant capacitor C2, the source of power switch device S2 is connected to the anode of diode D2 and the other end of resonant capacitor C2; the drain of power switch device S4 is connected to the cathode of diode D4 and one end of resonant capacitor C4, the source of power switch device S4 is connected to the anode of diode D4 and the other end of resonant capacitor C4; No. 2 DC power supply U dc2 The negative pole is grounded; Module n: (n-1) / 2 DC power supply U dc(n-1) / 2 The positive pole of the power switch device S n-1 and S n-3 The drain of the power switch device S n-1 The drain of the diode D n-1 The cathode and resonant capacitor C n-1 One end of the power switch device S n-1 The source of the diode D n-1 The anode and resonant capacitor C n-1 The other end of the power switch device S n-3 The drain of the diode D n-3 The cathode and resonant capacitor C n-3 One end of the power switch device S n-3 The source of the diode D n-3 The anode and resonant capacitor C n-3 The other end; (n-1) / 2 DC power supply U dc(n-1) / 2 The negative pole is grounded; DC power supply U dc1 / 2n The positive pole of the power switch device S n and S n-2 The drain of the power switch device S n The drain of the diode D n The cathode and resonant capacitor C n One end of the power switch device S n The source of the diode D n The anode and resonant capacitor C n The other end of the power switch device S n-2 The drain of the diode D n-2 The cathode and resonant capacitor C n-2 One end of the power switch device S n-2 The source of the diode D n-2 The anode and resonant capacitor C n-2 The other end; n / 2 DC power supply U dc1 / 2n The negative electrode of the power switch device S1 is grounded; the source of the power switch device S1 is connected to the drain of the power switch device S2 and one end of the inductor L1 at the same time, the source of the power switch device S3 is connected to the drain of the power switch device S4 and one end of the inductor L2 at the same time, the drain of the power switch device S1 is connected to the drain of the power switch device S3 at the same time, and the source of the power switch device S2 is connected to the source of the power switch device S4 at the same time. Power switch device S n-1 The source of the power switch device S n The drain and inductance L 1 / 2n One end of the power switch device S n-3 The source of the power switch device S n-2 The drain and inductance L 1 / 2(n-1) One end of the power switch device S n-1 The drain of the power switch device S n-3 The drain of the power switch device S n The source of the power switch device S n-2 The source of Inductor L1, L2, L3...L n / 2 The other end of is connected to the other end of the inductor L, one end of the inductor L is connected to one end of the resistor R and one end of the capacitor C, and the other end of the resistor R and the other end of the capacitor C are grounded; The power switch device adopts MOSFET, GTR or IGBT with reverse parallel body diode; It is characterized in that The method comprises the following steps: Step 1: The control method is completed by a hysteresis control module; Step 2: The hysteresis control module adopts four hysteresis controllers, and the hysteresis band is divided into four hysteresis bands to stagger the switching device to conduct; the four hysteresis bands are an upper hysteresis band of a positive half-wave, a lower hysteresis band of a positive half-wave, an upper hysteresis band of a negative half-wave, and a lower hysteresis band of a negative half-wave; the upper hysteresis band of a positive half-wave and the lower hysteresis band of a positive half-wave constitute the hysteresis band of a positive half-wave, and the upper hysteresis band of a negative half-wave and the lower hysteresis band of a negative half-wave constitute the hysteresis band of a negative half-wave; Step 3, the hysteresis band of the positive half-wave is controlled by S1, S2...Sx1...Sn-7, Sn-6 and S3, S4...Sx2...Sn-5, Sn-4 respectively; the hysteresis band of the negative half-wave is controlled by S8, S7...Sy1...Sn, Sn-1 and S6, S5...Sy2...Sn-2, Sn-3 respectively, wherein x1 is n%8=1 or n%8=2; x2 is n%8=3 or n%8=4, y1 is n%8=5 or n%8=6; y2 is n%8=7 or n%8=0, and n%8 represents the remainder after n is divided by 8; Step 4: Set the hysteresis band of the positive half-wave as shown in equation (3) and equation (4), and set the hysteresis band of the negative half-wave as shown in equation (5) and equation (6): Among them, i set To set the current, i set The setting is to make the switching frequency relatively fixed, i th The setting is to meet the working conditions of soft switching; i up is the upper hysteresis band; i out is a given current; i low is the lower hysteresis band; |i out| is the absolute value of the given current; Step 5: At this time, the hysteresis control module is set up, and the power switch devices S1, S2, S3, S4...S n Conductivity.

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