TW200536242A - High-efficiency high-boost-ratio DC/DC converter with reduced peak switch voltage stress - Google Patents

Abstract

The aim of this invention is to develop a high-efficiency high-boost-ratio DC/DC converter with reduced peak switch voltage stress. In general, a high-boost-ratio DC/DC converter is employed for many applications via the power source of low-voltage batteries. For examples, a high intensity discharge (HID) lamp, the high-voltage dc bus of an uninterruptible power supply (UPS), a travelling wave tube amplifier (TWTA), etc. In order to satisfy the requirement of high-voltage demand, a high-efficiency high-boost-ratio converter is one of the essential mechanisms in power supply systems with low-voltage sources. The high-efficiency high-boost-ratio DC/DC converter with reduced peak switch voltage stress utilizes a three-winding coupled transformer for providing a high conversion ratio without the extreme switch duty-cycle. This three-winding coupled inductor is also facilitated to reduce peak switch voltage stress for decreasing the conduction loss, and to reduce the turn-off rate of the output diode for alleviating the reverse-recovery problem. It can achieve the property of high-efficiency power conversion. The high-efficiency high-boost-ratio DC/DC converter with reduced peak switch voltage stress can be used for low-voltage sources, such as conventional batteries, fuel cells, photovoltaic and wind energy, to further increase the energy utility rate.

Description

200536242 Description of the invention: [Technical field to which the invention belongs] Many power supply applications, such as gas-discharge headlamps, high-voltage DC busbars of inverters in uninterruptible power systems, wideband traveling wave tube amplifiers, etc. 5 require high voltage DC power supply, however, traditional batteries are generally used as the power source, so the development of high boost ratio converters is a necessary power conversion mechanism. The high efficiency and high boost ratio converter with reduced switching withstand voltage performance of the present invention can convert the low output voltages of traditional storage batteries, fuel cells, solar power and wind power to high voltage DC power supply systems, which greatly improves energy utilization. Rate and increase power supply stability. The technical field covered by the present invention includes the fields of power electronics, DC / DC converter technology and energy technology. Although the technical field involved in the present invention is extensive, it mainly lies in the development of high efficiency and high boost ratio with reduced switching withstand voltage performance. Converter devices to improve the lack of conventional converters. [Previous technology] The traditional boost converter can control the boost ratio of the output voltage by adjusting the duty cycle of the switch. When it is applied to a high boost ratio, the duty cycle needs to be adjusted to a maximum value. However, the equivalent resistance (ESR) of the inductor in the converter causes the boost ratio to be limited. It cannot operate in a situation where the boost ratio exceeds 7 times and the conversion efficiency is poor. In addition, when the power semiconductor switch of the boost converter is turned off, the voltage value at both ends is the output voltage, which is a voltage that is several times higher than the input voltage. This forces the power semiconductor switch to choose a MOSFET with a high withstand voltage. However, It has a large on-resistance value (Rds (On)), resulting in a higher on-conduction loss. In addition to this, there is a problem of reverse recovery (Reverse_Reverver) in the diode of the traditional step-up 200536242 converter. During the transient state of the power semiconductor switch, the diode must use an instantaneous high current to establish the reverse Bias voltage, this current flows through the power semiconductor switch, causing severe switching losses and low conversion efficiencies. Based on the above, the traditional boost converter does not have a high boost ratio function. Therefore, it is limited to DC power conversion applications with a boost of 7 times or less, and cannot achieve a high-efficiency power conversion mechanism. Therefore, many experts have learned to propose a boost commutation technology to improve the above-mentioned traditional pressure-type commutation SlL as a disadvantage. The following is a comparison of the world's leading boost converter technologies to further highlight the advantages of the invention's breakthrough in high efficiency and high boost ratio converter technology with reduced switching withstand voltage performance. 1. C. W. Roh, S. H. Han, M. J. Youn, "Dual coupled inductor fed isolated boost converter for low input voltage applications," Electronics Letters, vol. 35, pp. 1791-1792 , 1999. 2 ···· S. Da Silva, L. dos Reis Barbosa, J. · B · Vieira, Jr ·, L · C. De Freitas, and VJ Farias, ccAn improved boost PWM soft-single-switched converter with low voltage and current stresses / 5 IEEE Transactions on Industrial Electronics, vol. 48? pp. 1174-1179, 2001. 3. Q · Zhao, and F · C · Lee, "High-efficiency, high step-up DC-DC converters / 5 IEEE Transactions on Power Electronics, vol. 18, pp. 65-73, 2003. 4 · DC Lu, D · K. W · Cheng, and Y · S · Lee, "A single-switch continuous-conduction-mode boost converter with reduced 200536242 reverse-recovery and switching losses / ^ IEEE Transactions on Industrial Electronics, vol. 505 pp. 767-776, 2003. 5. K. Himchi, and M. Nakaoka, UUPS circuit configuration incorporating buck-boost chopper circuit with two magnetically coupled co ils, 59 Electronics Letters, vol. 395 pp. 1345-1346, 2003. 6 ·····························, ·, Duarte, and I ·· Barbi, "An improved family of ZVS-PWM active-clamping DC-to-DC converters / 5 IEEE Transactions on

Power Electronics, vo \. 17? Pp. L-7? 2002. References Input Voltage Output Voltage Output Capacity Conversion Efficiency Circuit Architecture Comparison of Advantages and Disadvantages [1] 12V 150V 90W 87% Advantages of Dual Coupling Inductor • Disadvantages of South Boost Ratio: Complex structure [2] 80V 200V 400W 97.5% Advantages of transformer: Flexible switching Disadvantages: Up to four times the boost ratio [3] 60V 380V lkW 91.8% Lima joint system ^ Worry points: Simple structure and use of low conduction loss parts (250V switch) Disadvantages: The step-up ratio cannot be greatly improved, the efficiency is not good when the voltage is low, and the inductive L_wave of the line can not be overcome. [4] 100V 150V 200W 95% _Mahe resonance Advantage: Flexible switching Disadvantage: Boost ratio Low and large inductance capacity [5] 48V 340V 700W 86% Uninterruptible power system ——- ^ y v. Advantages: Single-stage DC boost to AC Disadvantage: Cannot be used for voltage transformer 200536242 and switch withstand voltage south [6] 300V 400V 1.6kW 98% active clamping Advantages: Flexible switching Disadvantages: Low boost ratio and high clamping voltage The disclosed high-efficiency high boost ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention uses three-winding coupling This makes the iron powder core operate more efficiently and globally. Without increasing the duty cycle of the power semiconductor switch, the boost ratio of the traditional boost converter can be greatly improved, and it can help reduce the voltage withstand specifications of the switch. In order to reduce the conduction loss, on the other hand, because the coupling and coupling inductors have the characteristics of leakage inductance, the surge current at the output diode is reversely reversed, and the purpose of converting a high-efficiency low-voltage DC power source into a high-voltage DC power source is achieved. [Summary of the Invention] FIG. 1 shows a block diagram of a high-efficiency, high-boost-ratio converter with reduced switching voltage performance disclosed by the present invention. The present invention utilizes a DC input power supply, and after the disclosed high-efficiency and high-boost-ratio converter converter with reduced switching withstand voltage performance, the level of the DC input voltage γ is greatly improved after the source conversion, which can be applied to high-voltage demand Occasions; when the power semiconductor switch S of the primary circuit 102 is turned on, the energy of the DC input voltage source is first stored in the coupling inductor primary side of the primary circuit 102, and the energy of the DC input voltage source is stored three times through the coupling inductor. In the capacitor C3 of the side circuit 104, when the power semiconductor switch S of the primary circuit 102 is turned off, the DC input voltage source, the coupled inductor primary side, the capacitor C2 of the secondary side circuit 103, and the capacitor C3w of the tertiary side circuit 104 are connected in series. When the DC output circuit 105-11200536242 diode A is turned on, it is conducted to the DC output circuit i05 in a current mode to increase the DC output voltage of the converter. At this time, the capacitance C2 of the secondary circuit 103 and The capacitor C3 of the tertiary-side circuit 104 withstands the cross-voltage of most DC output circuits 105. The difference between the DC output voltage and this cross-voltage is the primary side. The voltage on both ends of the power semiconductor switch S of the circuit 102 is much smaller than the DC output voltage. Therefore, the power semiconductor switch of the primary circuit 102 has a low withstand voltage performance; the primary current of the coupling inductor begins to decrease and gradually becomes zero. Due to the continuous magnetic flux characteristics of the iron powder core, the second-side current 103 of the coupled inductor rises from zero crossing. When it approaches the peak value, the capacitor C2 of the secondary-side circuit 103 starts to be charged. Reach balance within the cycle. The principles and comparative effects of the present invention to improve the prior art are as follows: 1. The combination of the primary circuit 102, the secondary circuit 103, and the tertiary circuit 104 has the effect of increasing the boost ratio and reducing the withstand voltage specifications of the power semiconductor switch S. Utilizing the characteristic that the number of handle inductors is proportional to the voltage 'The device of the present invention has a high step-up ratio and provides a step-up ratio higher than that of a conventional step-up converter; the capacitor C2 of the secondary circuit 103 And the voltage on the capacitor C3 of the tertiary circuit 104 shares the voltage across the power semiconductor switch S of the primary circuit 103 so that this voltage is lower than the output voltage & of the DC output circuit 105. 2. Reduce the power semiconductor switch 5 withstand voltage specification to reduce the conduction loss: the voltage across the two ends of the power semiconductor switch S of the primary circuit 102 is limited to the low voltage range. A MOSFET with a lower withstand voltage can be selected because it has a lower voltage. The on-resistance can reduce the conduction loss, which improves the conversion efficiency. 12 200536242 3. Coupling inductance increases utilization rate of iron powder core: Using the three-winding coupling inductance, when the power semiconductor switch is turned on, the current on the third side of the coupling inductor charges the capacitor C3 on the third-side circuit 104, similar to the traditional forward commutation. The working principle of the current transformer; when the power semiconductor switch S is turned off, the energy stored in the coupled inductor passes through the secondary side of the coupled inductor, releases energy to the load end, and then charges the capacitor C2 of the secondary side circuit 103. This working principle is traditional Flyback converters are similar; based on the above, the coupling inductance of the three windings under full-range operation increases the utilization of the iron core of the coupled inductor. 0 4. The leakage inductance of the coupled inductor reduces the problem of reverse recovery of the output diode: When the power semiconductor switch of the primary circuit 102 is turned off, the output diode is turned on. 5 The current slope of the diode is the leakage inductance of the inductor. The function 'its current decreases to zero and cuts off, which reduces the problem of reverse recovery, does not cause reverse current surges, reduces component heating and power consumption, and thereby improves conversion efficiency. 5. Closed loop control mechanism: Generally, the DC input voltage γ of the DC input circuit 101 is easy to change with the load. It can be stabilized by the closed loop control mechanism 106 _ DC output voltage of the DC output circuit 105 &. [Embodiment] FIG. 2 shows an equivalent circuit of a high-efficiency and high-boost converter with reduced switching withstand voltage efficiency disclosed in the present invention, in which a three-winding coupled inductor uses a set of one-to-two ideal transformers, excitation inductors & The equivalent leakage inductance 4 is represented, and the number of turns of this ideal transformer is TV3, and the number of turns is seven and can be expressed as follows: ⑴ n2 ~ 13 200536242 The cover of the right-hand side is assumed, the capacitance q of the secondary circuit and one person The capacitance C3 of the electric test phen 104 is large enough to be regarded as a constant voltage source, the voltages of which are dagger 2 and dagger 3, respectively, and the DC input circuit 101 is simplified as a constant voltage source. Figure 3 Table 7F Migration and current waveform timing. FIG. 4 shows the working mode of the present invention, and its description is as follows: Mode 1 丨 ϋ j:… when the time is wide, the power semiconductor switch s is turned on, and the diodes q and 2 are reversed and the unipolar body A is turned on. At this time, the DC input voltage Capacitor C3 is charged through the coupling circuit of the tertiary circuit 104, and the charging current of the capacitor can be deduced via Kirchhoff voltage = law. The rate of change of the magnetizing inductance and the light-winding inductance of the secondary side is as follows:- (3) dt < Lk a-vs dt — 0 + Ά -h dt and the voltage across the magnetizing inductance (4) n ^ Lm (5)

⑹ Mode-In the DC input voltage, the magnetizing current is charged with the leakage inductance and the capacitance q of the tertiary circuit 1 () 4 to store energy in the magnetizing inductance.

An, leakage inductance & capacitor C3. Module 14 200536242 Voltage: ΓΓΓΤ switch s is turned off, the two ends of the switch are electrically reversed, and the current is flowing through the electric valley C2 of Erdi Road 103 and the private ideal transformer 11 of the secondary side circuit 11 through the county In a combined manner, the excitation is conducted to the secondary side of the ideal transformer, and the secondary side of the transformer goes to the DC output circuit 105 to release energy to the load. Using 2 grams of ::: voltage law, the relationship of voltage can be derived as follows. Kirchhoff

Vds (0 + ^ C2 ^ ^ C3 ^ Vc2 = -n2 ^ vNl (t)

V

Lm C3 ⑺⑻ (9) At this time, the withstand voltage of the switch is vds (〇 = ys ^^ m (〇-vLk (t) = V〇-VC2-VC3 < κ). It can be known from formula (10) that this commutation II has the effect of reducing _withstand voltage, which helps to select the semiconductor switching elements with low withstand voltage and low conduction loss, and the conversion efficiency of the device. Using the above,… The above is the voltage on the inductor 4 and the leakage inductance 4 of the coupled inductor. The current change rate can be deduced as follows: (10) ^ Lrn dt ^ JA dt n2Lm vs + Vc3} ± (^ n2) V (n2 Lk (11) C2 15 (12) (13) 200536242 di Zou =-(l + n2 + Lk / LJVC2 dt n2 Lk dt ^ Π-, + ^ + ^ 3) + (1 + n2) VC2 (14) n2

Jk_ 2 T ηΊ L Mode 3 [i2 ~ i3 J: When the time is G, the discharge current of the capacitor C2 of the secondary circuit decreases to

Zero value, / C2 (/ 2) = 0. The energy of the magnetizing inductance passes through the ideal transformer to charge the capacitor q of the secondary circuit 103. Therefore, the current of the capacitor Q is negative, and the current change rate is as shown in equation (14). Means. On the other hand, the capacitor C * 3 of the tertiary side circuit 104 continuously discharges to the load, and its current change rate can be expressed by equation (12), and the current of the series path decreases with time. 1 Mode Four [ί3 ~ 々]:

Tian Ri Shoujian ^ Day t, the current on the primary side of the coupled inductor decreases to the value of Wen =) = 〇 'The stored energy of the coupled inductor is based on the combined inductor 2 ::: see, the temple diode, The electric means, 'can reduce the ceramic end diode. The current change rate is as follows: 2; 0_3 of the electric valley q charge' excitation inductance reduction 'T circuit. The capacitance of 3 varies with electric current ;: VC2 ^ n22 L (15 secondary side circuit 1023 2. One pole body current 'and the magnetizing inductor current ^ 16 200536242 proportional relationship, the diode current' also showed Linear decreasing function. Since the leakage inductance current is zero, the current change rate is also zero, so the voltage on the leakage inductance is zero, which makes the voltage of the power semiconductor switch s decrease. The voltage value across the power semiconductor switch can be expressed as (16) Assuming that all components are ideal, the capacitor voltage factory of the secondary side circuit 103 and the capacitor voltage FC3 of the tertiary side circuit 104 can be expressed as Vci ^ -n2vLm {t), tx < t < tA (Π)

Vc ^ (l + n3) Vs (18) The duty cycle for turning on the power semiconductor switch S is d, using formula (6), formula (9), formula (17), formula (18) and the magnetizing inductance in a cycle The average voltage within zero can be derived as follows: ^ = (l + „3) + _i_ + _ ^ _, 2 (19) As can be seen from equation (19), the boost ratio of this circuit is high The traditional boost converter is able to compensate the deficiency of the boost ratio of the traditional boost converter by adjusting the turns ratio. Fig. 5 shows that the high rate of reducing the withstand voltage performance of the switch disclosed in the present invention is still high. One of the embodiments of the voltage ratio converter, the low voltage power source used is the American bandit H_P0 body, the fuel cell P_rPEMTM-PS250 produced by the company, and the output power of this Chu Zhen is 250 watts. The rated output voltage is 28 volts c. Γ: The voltage of the two-cell output reduces the switch riser. The inverter element of the present invention is selected. The power is 4 17 200536242. The semiconductor switch S uses IRFPS4710 (100V, RDS (ON) = 14mQ). The lower on-resistance is beneficial to reduce the on-conduction loss and greatly improve the conversion efficiency of the converter. The Schottky diode is used as the diode SR20100 can also reduce its conduction voltage to improve efficiency. Diodes 2 and 3 are selected as SFA1608. Parallel damping circuit RCD is used at the ends of diodes 2 and 3 to reduce the reverse bias of the diode. When the voltage surge is caused by the parasitic capacitance of the diode and the leakage inductance resonance of the secondary and tertiary sides of the coupled inductor, the closed-loop control mechanism 106 uses a TL494 pulse width modulation control chip, and the frequency operation of the power semiconductor switching element At 100kHz, the output power is 20 ~ 300 Watts. The detailed specifications of this embodiment are as follows: β 27 ~ 38V V0: 400V R0: 534 ^ 80000 C2: 4.75 μ ¥ C3: 4.75 // F Ct: 2200 // F C0: 100 // F Lx: 10.7 // H Lk: 0.6 // H n2 ·· 6.33 «3: 5 The embodiment of the high efficiency and high boost ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention First, when operating at an output power of 300 watts, the measurement efficiency is 94.1%, and the measured waveform response is recorded as follows. Figure 18 Table 18 200536242 shows the voltage and current measured waveforms of the power semiconductor switch s. The power is shown in the figure The parasitic capacitance is charged when the semiconductor switch is turned off, The terminal voltage rises, due to the influence of line leakage inductance, the switching voltage has the phenomenon of oscillation, this voltage is about 60 volts when stable. Figure 7 shows the coupled inductor primary side current L, coupled inductor secondary side current k, and coupled inductor tertiary side current. k The measured waveform shows the response of the primary and secondary currents of the coupled inductor during the energy transfer in the coupled inductor, and the charging current to the capacitor C3 on the tertiary side of the coupled inductor. Figures 8 (a), (b), and (c) show the voltage and current waveforms of diodes 0, 2, and D3, respectively. Figure 8 (a) shows that diode A has almost no reverse direction when it is turned off. The current surge effectively reduces the problem of reverse recovery. Figure 9 shows the response of the DC output voltage, DC output current 4 and DC input current / z. Of the fuel cell when the load changes between 0 watts of no-load output power and 300 watts of full-load output power, in cooperation with the closed-loop control mechanism 106 Under high-frequency operation, the ripple of the DC input current of the fuel cell and the output voltage of the DC output circuit 105 is small, which enables the fuel cell to work stably and output a DC voltage of 400 volts. FIG. 10 shows one of the embodiments of the high-efficiency and high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention, which uses a fuel cell as a DC input voltage and operates at different output powers corresponding to the conversion efficiency, the highest conversion Efficiency is greater than 95%. FIG. 11 shows a block diagram of another preferred embodiment of the high-efficiency and high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed in the present invention. The biggest difference between FIG. 1 and FIG. 11 lies in the auxiliary circuit 1104. The capacitor Q of the auxiliary circuit 1104 further increases the output voltage of the DC output circuit and absorbs the leakage in the circuit. 19 200536242 Leakage inductance causes the surge voltage of the power semiconductor switch s. When the power semiconductor switch s is turned off, the low voltage on the primary side of the coupling inductor is large. The current passes through the auxiliary circuit 1104's diode A to charge the capacitor Q, and the capacitor absorbs the energy of the leakage inductance in the line of the primary circuit 102 to reduce the peak voltage oscillation of the power semiconductor switch. On the other hand, since the primary side current of the coupled inductor charges most of the capacitor Q, the peak current of the diode flowing through the DC output circuit 105 is reduced, and this current path also passes through the inductance A of the auxiliary circuit 1104. The purpose of this inductance is to reduce The small current climbing rate strengthens the function of reducing the peak current of the diode A of the DC output circuit 105, makes the current more even, and reduces the conduction loss. FIG. 12 shows another preferred embodiment of the high efficiency and high boost ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention. The fuel cell is used as a DC input voltage, a DC output voltage of 400V and an output power of 300W. Figure 12 (a) is the voltage and current of the diode ZV of the DC output circuit 105. Compared with the current waveform 5 of Figure 8 (a), Figure 5 (a) shows that the current peak is significantly reduced and averaged. This current path Lead to the high-voltage side of the 105 φ DC output circuit. This preferred embodiment has high-voltage low-current and low-voltage large-current characteristics. It fully utilizes the characteristics and capacity of the components to reduce the output voltage and current ripple; Figure 12 (b) is The voltage and current of the diode of the auxiliary circuit 1104 show that when the power semiconductor switch S is turned off, most of the coupling inductance flows through the diode A of the auxiliary circuit 1104 to charge the capacitor of the auxiliary circuit 1104. Although the present invention has been disclosed in the foregoing preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can still depart from the spirit of the present invention within the scope of 2005 200536242 and various changes and modifications. The scope of protection of the invention shall be determined by the scope of the attached patent application. [Brief description of the figure] FIG. 1 shows a block diagram of a high-efficiency high-boost converter with reduced switching withstand voltage efficiency disclosed by the present invention. FIG. 2 shows an equivalent circuit diagram of a high-efficiency, high-boost converter with reduced switching withstand voltage efficiency disclosed by the present invention. FIG. 3 shows the waveform sequence of voltage and current of the high-efficiency and high-boost converter with reduced switching withstand voltage efficiency disclosed by the present invention. FIG. 4 shows a high-efficiency, high-boost-ratio converter with reduced switching voltage withstanding efficiency, and a circuit working mode diagram of the present invention. FIG. 5 shows a circuit diagram of a high-efficiency high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention, using a fuel cell as a power supply. FIG. 6 shows one embodiment of a high-efficiency, high-boost-ratio converter with reduced switching and low voltage efficiency disclosed by the present invention, the measured waveform of the power semiconductor switch S across the voltage and the current dagger. FIG. 7 shows one of the embodiments of the high-efficiency and high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed in the present invention, the coupled inductor primary-side current L, the coupled inductor secondary-side current //), and the coupled inductor tertiary-side Current / D3 measured waveform. FIG. 8 shows one embodiment of the high-efficiency and high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed in the present invention. The measured voltage and current waveforms of the diodes are: (a) the voltage across the diode A of the DC output circuit and Current 21 200536242

Zw; (b) Diode A across voltage of secondary circuit% 2 and current core 2; (C) Diode of tertiary circuit is 3 voltage across vD3 and current k. FIG. 9 shows one embodiment of a high efficiency and high boost ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention. The DC output voltage G, the DC output current tolerance, and the DC input current Λ of the fuel cell when the load changes Transient measured waveform. FIG. 10 shows one embodiment of the high-efficiency high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention, which operates at different output power corresponding to the conversion efficiency. FIG. 11 shows a block diagram of another preferred embodiment of the high-efficiency high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention. FIG. 12 shows another preferred embodiment of a high-efficiency and high-boost-ratio converter with reduced switching withstand voltage efficiency disclosed by the present invention. The measured voltage and current waveforms of the diodes are: (a) Diode A span of the DC output circuit Voltage and current; (b) Diode voltage and current / 仏 of auxiliary circuit. The numbers of the main parts of the figure represent the following meanings: _ 101: DC input circuit 102: — Secondary side circuit 103: Secondary side circuit 104: Tertiary side circuit 105: DC output circuit 106: Closed-loop control mechanism 1104: Auxiliary circuit 22

Claims (1)

200536242 Scope of patent application: A high-efficiency and high-boost converter with reduced switching withstand voltage performance, which includes a DC input circuit: a DC input voltage and an input filter capacitor;-Secondary circuit: a coupled inductor primary side and a power semiconductor switch The circuit is composed of a secondary side of a coupled inductor, a diode and a capacitor; a circuit of a tertiary side: a third side of a coupled inductor, a diode and a capacitor; Current output circuit: a diode, output filter capacitor and load; a closed-loop control mechanism: the error value is generated by comparing the voltage command with the voltage feedback, and it is controlled by proportional integral control, pulse width modulation, and the drive amplifier circuit. The output is the drive signal with adjustable duty cycle ratio, which triggers and cuts off the power semiconductor switch. When the power semiconductor of the primary circuit is turned on, the energy of the DC input voltage is stored on the primary side of the coupled inductor of the primary circuit. The field current type is stored, and the DC input voltage source is The quantity is transferred to the capacitance of the tertiary circuit based on the principle of a transformer; when the power semiconductor switch of the primary circuit is turned off, the DC input voltage, the capacitance of the coupled inductor primary, secondary circuit, and the capacitance of the tertiary circuit are connected in series. Energy, when the DC output circuit 23 200536242 is turned on, the current is conducted to the DC output circuit to increase the DC output voltage of the converter; at this time, the capacitance of the secondary circuit and the capacitance of the tertiary circuit bear most of it. The voltage across the DC output circuit. The difference between the DC output voltage and this voltage is the voltage across the power semiconductor switch of the primary circuit. This voltage is much smaller than the DC output voltage, so the power semiconductor switch of the primary circuit has a low voltage. Efficiency of withstand voltage; During the current of the primary side of the coupled inductor begins to decrease and gradually becomes zero, due to the continuous characteristics of the iron powder core, the secondary side current of the coupled inductor rises from zero crossing. When it approaches the peak, the secondary Capacitor of the side circuit; The characteristics of this device are: First, the device has the characteristics of high boost ratio The second point is that the device uses the coupling inductance of three windings to improve the utilization rate of the high-frequency magnetic element iron powder core. The third point is that the device can reduce the voltage resistance of the switch, which can reduce the The withstand voltage specification of the power semiconductor switch of the primary circuit, that is, the MOSFET with a lower on-resistance can be selected to reduce the conduction loss; the fourth point, the filtering inductor can be omitted at the output end; the fifth point, the diode used in the DC output circuit The Schottky diode with low voltage and low on-voltage can reduce the conduction loss. The sixth point of this device is that the circuit of this device has the characteristics of low current on the low side and low current on the south side. It can fully use the specifications and capacity of the component, so the efficiency Higher than conventional circuits. 2. The high-efficiency and high-boost converter with reduced switching withstand voltage performance as described in item 1 of the scope of patent applications, where the capacitor of the DC input circuit is made of general electrolytic capacitors or supercapacitors, which can absorb high-frequency harmonics. Wave energy 24 200536242 component 5 stabilizes the DC input voltage. 3. High efficiency and high boost ratio converter with reduced switching withstand voltage performance as described in item i of the patent, in which the capacitor of the DC wheel output circuit has the main function of absorbing the instantaneous charging current from the secondary circuit. The component of high-frequency harmonic energy and stabilizes the output voltage of the DC output circuit. 4 · If special: The high-amplitude step-up ratio converter with reduced switching withstand voltage performance as described in J Shenye's target circle item # 1, where the primary-side circuit, secondary-side circuit, and primary-side circuit are coupled inductors The principle of energy transfer is to divide the primary side of the coupling inductor into three phases to increase the voltage. In the first phase, when the power semiconductor switch is turned on, the primary side circuit's coupling inductor is charged on the primary side, and through the transformer operation principle, When the diode of the side circuit is forward biased, the capacitor of the circuit is charged; in the second stage, when the power semiconductor switch is turned off, the diode of the secondary side circuit is forward biased, and the energy stored in the primary side of the switching inductor is stored. According to the flux immortality theorem, the energy is released to the load in the current mode. In the third stage, when the power semiconductor is still off, the residual magnetic flux φ bin b stored in the primary side of the coupled inductor is stored in the secondary magnetic flux immortal theorem. The capacitor of the side circuit is charged. 5. High efficiency 咼 boost ratio converter with reduced switching withstand voltage performance as described in item 丨 of the scope of patent application, where the primary side circuit, secondary side circuit and secondary side circuit are combined to reduce the switching withstand voltage Efficiency, limiting the maximum voltage of the primary circuit. 6. The “efficiency” boost ratio converter with reduced switching withstand voltage performance as described in item 丨 of the scope of patent application, where the DC input voltage source, the scope of this patent application includes storage batteries, solar cells, and DC wind power generators. 200536242 Motors and AC wind turbines are rectified into DC power for power supply. 7. The high efficiency and high boost ratio converter with reduced switching withstand voltage performance as described in item 1 of the scope of patent applications, where the DC input voltage source can be connected in parallel with two or more different power supplies to control the power input Power ratio to increase the overall DC power output. 8. The high efficiency and high boost ratio converter with reduced switching withstand voltage performance as described in item 1 of the scope of patent application, where the load of the DC output circuit, 0 The scope of this patent application includes the DC output voltage of this patent, Provide inverter, AC / DC motor control device, front-end power supply or direct application circuit device. 9. A high-efficiency, high-boost converter with reduced switching withstand voltage performance, which includes a DC input circuit: constructed by a DC input voltage and an input filter capacitor. P, —— secondary circuit: one coupled inductor once Side and a power semiconducting body switch; primary and secondary circuit: a coupled inductor secondary side, a diode and a capacitor; a tertiary circuit: a coupled inductor tertiary side, a two pole Body and a capacitor; an auxiliary circuit: a capacitor, an inductor and a diode. A DC output circuit: a diode, output filter capacitor and load 26 200536242; a closed-loop control mechanism: an error value is generated by comparing the voltage command with the voltage feedback, and is controlled by proportional integral, pulse width modulation and driving The output of the amplifying circuit 5 is a driving signal with adjustable duty cycle ratio, which triggers and cuts off the power semiconductor switch. The characteristics of this device are: First, the device has the characteristics of high boost ratio, which greatly improves the DC output voltage level; second Point, this device uses the three-winding coupling inductance to improve the utilization rate of high-frequency magnetic element iron powder core; third point, this device has the ability to reduce the withstand voltage of the switch, which can reduce the withstand voltage of the power semiconductor switch of the primary circuit Specifications, you can choose a MOSFET with a lower on-resistance to reduce the conduction loss; the fourth point, the filter inductor can be omitted at the output end; the fifth point, the low-voltage, low on-voltage Schottky diode used in the DC output circuit The pole body can reduce the conduction loss; sixthly, the device circuit has the characteristics of high current on the low side and low current on the high side, which can be charged Specifications and use of the capacity element, and therefore more efficient than conventional circuit; Seventh, the use of auxiliary circuits Lu body diode of the low-pressure, low-Schottky diode on-voltage, the conduction loss can be reduced. 10. As described in item 9 of the scope of patent application, a high-efficiency and high-boost converter with reduced switching withstand voltage performance, wherein the capacitor of the DC input circuit is made of general electrolytic capacitor or super capacitor, which can absorb high-frequency harmonics. The component of wave energy stabilizes the DC input voltage. 11. The high-efficiency and high-boost ratio converter with reduced switching withstand voltage performance as described in item 9 of the scope of patent applications, wherein the auxiliary circuit has the following functions: 27 200536242 Little one's auxiliary circuit with six voltage ratio function; The second converter device has the function of raising the lift again ", the capacitance of the auxiliary circuit and the group port of the diode, and the function of the voltage surge caused by the leakage inductance on the switch due to the leakage inductance on the line; the third point, The auxiliary rib subsidizes the combination of the electric valley, the diode and the inductor of the private road with the function of reducing the peak value of the diode current and the average current of the DC wheel. 12 ·: ί :! Please refer to the item 9 in the range to reduce the switch withstand voltage performance: Second: the compression ratio converter 'of which-the secondary side circuit, secondary side circuit to reduce secondary side circuit, to reduce _ & Maximum voltage of voltage-efficiency side circuit. 13 · = In the patent, please ask for the range 帛 9 with the gate-to-amp ratio to reduce the withstand voltage performance of the step-up ratio converter, in which the DC input voltage source, the scope of this patent application includes batteries, solar cells, DC wind power Generators and AC wind turbines are rectified into DC power and used as power supply. 14. For high-efficiency and high-boost-rate converters with high voltage-reduction performance, as described in item 9, please refer to the DC input voltage source. , You can connect two or more different power supplies in parallel and control the ratio of the input power of the power supply to increase the overall DC power output power. 15. The load of the DC output circuit in the high efficiency and high boost ratio converter with reduced on-voltage performance as described in item 9 of the scope of patent application. The scope of this patent application includes the provision of the DC output voltage of this patent. In contrast, IL is the front-end power supply of the parent DC motor control device or a direct application circuit device. U 28