阅读说明：本技术 一种2000w车载逆变器的主电路 (Main circuit of 2000W vehicle-mounted inverter ) 是由 王大钊 毕嗣君 祝军 兰士凤 赵英 于 2020-12-22 设计创作，主要内容包括：一种2000W车载逆变器的主电路,涉及一种车载逆变器的主电路。解决了现有车载逆变器功率小,使用受限的问题。本发明采用两路1000W拓扑电路的正负信号输入端分别连接电池的正负极,两路1000W拓扑电路的正极输出端连接整流滤波电容的一端,两路1000W拓扑电路的负极输出端连接整流滤波电容的另一端；整流滤波电容的一端还连接逆变电路的高压侧信号输入端,整流滤波电容的另一端还连接逆变电路的低压侧信号输入端；逆变电路的信号输出端连接LC低通滤波器的信号输入端,所述LC低通滤波器的信号输出端连接后级EMI滤波电路的信号一端,所述后级EMI滤波电路另一端为2000W车载逆变器的主电路的信号输出端。本发明适用于车载使用。(A main circuit of a 2000W vehicle-mounted inverter relates to a main circuit of a vehicle-mounted inverter. The problems that an existing vehicle-mounted inverter is small in power and limited in use are solved. The positive and negative signal input ends of two 1000W topological circuits are respectively connected with the positive and negative electrodes of a battery, the positive output ends of the two 1000W topological circuits are connected with one end of a rectifying and filtering capacitor, and the negative output ends of the two 1000W topological circuits are connected with the other end of the rectifying and filtering capacitor; one end of the rectification filter capacitor is also connected with a high-voltage side signal input end of the inverter circuit, and the other end of the rectification filter capacitor is also connected with a low-voltage side signal input end of the inverter circuit; the signal output end of the inverter circuit is connected with the signal input end of the LC low-pass filter, the signal output end of the LC low-pass filter is connected with one signal end of the rear-stage EMI filter circuit, and the other end of the rear-stage EMI filter circuit is the signal output end of the main circuit of the 2000W vehicle-mounted inverter. The invention is suitable for vehicle-mounted use.)

1. A main circuit of a 2000W vehicle-mounted inverter is characterized by comprising two 1000W topological circuits, a rectifying filter capacitor, an inverter circuit, an LC low-pass filter and a post-stage EMI filter circuit;

the positive and negative signal input ends of the two 1000W topological circuits are respectively connected with the positive and negative electrodes of the battery, the positive output ends of the two 1000W topological circuits are connected with one end of the rectifying and filtering capacitor, and the negative output ends of the two 1000W topological circuits are connected with the other end of the rectifying and filtering capacitor;

one end of the rectification filter capacitor is also connected with the high-voltage side input end of the inverter circuit, and the other end of the rectification filter capacitor is also connected with the low-voltage side input end of the inverter circuit;

the signal output end of the inverter circuit is connected with the signal input end of the LC low-pass filter, the signal output end of the LC low-pass filter is connected with one signal end of the rear-stage EMI filter circuit, and the other end of the rear-stage EMI filter circuit is the signal output end of the main circuit of the 2000W vehicle-mounted inverter.

2. The main circuit of a 2000W vehicle inverter according to claim 1, wherein the 1000W topology circuit comprises a common mode filter M1, a MOS transistor Q1, a direct current filter capacitor C1 and a push-pull boosting circuit;

the positive and negative signal input ends of the common mode filter M1 are respectively connected with the positive and negative electrodes of the battery, the positive output end of the common mode filter M1 is connected with the source electrode of the MOS tube Q1, the drain electrode of the MOS tube Q1 is connected with one end of the direct current filter capacitor C1, the other end of the direct current filter capacitor C1 is connected with one end of a resistor R1, and the other end of the resistor R1 is connected with the negative output end of the common mode filter M1;

one end of the direct current filter capacitor C1 is also connected with the positive input end of the push-pull booster circuit, the other end of the direct current filter capacitor C1 is also connected with the positive and negative input ends of the push-pull booster circuit, and the positive and negative output ends of the push-pull booster circuit are connected with the two ends of the rectifying filter capacitor.

3. The main circuit of a 2000W vehicle inverter according to claim 1 or 2, wherein the push-pull boost circuit comprises a MOS transistor Q3, a MOS transistor Q4, a high frequency transformer T1, a resonant inductor L3, a resonant capacitor C3 and a rectifier bridge B1;

the source electrode of the MOS tube Q3 is connected with the source electrode of the MOS tube Q4, the source electrode of the MOS tube Q3 is the positive input end of the push-pull booster circuit, and the center tap of the primary side of the high-frequency transformer T1 is the negative input end of the push-pull booster circuit;

the drain electrode of the MOS transistor Q3 and the drain electrode of the MOS transistor Q4 are respectively connected with two ends of the primary side of the high-frequency transformer T1;

one end of the secondary side of the high-frequency transformer T1 is connected with one end of a resonant inductor L3, the other end of the resonant inductor L3 is connected with one end of a resonant capacitor C3, and the other end of the resonant capacitor C3 is connected with an alternating current input end of a rectifier bridge B1;

the other end of the secondary side of the high-frequency transformer T1 is connected with the other alternating current input end of the rectifier bridge B1, and the positive output end and the negative output end which are connected with the rectifier bridge B1 are respectively connected with two ends of the rectifying filter capacitor.

Technical Field

The invention relates to a main circuit of a vehicle-mounted inverter.

Background

In long-distance traveling, especially when large trucks are going out, drivers spend most of their time in vehicles, so that high-power vehicle-mounted electric appliances are indispensable for use in vehicles due to the needs of daily life, such as kettles, electric rice cookers, microwave ovens and other electric appliances.

The conventional 300W and 1000W vehicle-mounted inverter is only suitable for some entertainment equipment, such as a mobile phone charger, a notebook computer and the like, due to power limitation, and cannot use some common living electric appliances, so that the development of a 2000W inverter is urgent.

Disclosure of Invention

The invention aims to solve the problems of low power and limited use of the conventional vehicle-mounted inverter and provides a main circuit of a 2000W vehicle-mounted inverter.

The main circuit of the 2000W vehicle-mounted inverter comprises two 1000W topological circuits, a rectifying filter capacitor, an inverter circuit, an LC low-pass filter and a post-stage EMI filter circuit;

the positive and negative signal input ends of the two 1000W topological circuits are respectively connected with the positive and negative electrodes of the battery, the positive output ends of the two 1000W topological circuits are connected with one end of the rectifying and filtering capacitor, and the negative output ends of the two 1000W topological circuits are connected with the other end of the rectifying and filtering capacitor;

one end of the rectification filter capacitor is also connected with a high-voltage side signal input end of the inverter circuit, and the other end of the rectification filter capacitor is also connected with a low-voltage side signal input end of the inverter circuit;

the signal output end of the inverter circuit is connected with the signal input end of the LC low-pass filter, the signal output end of the LC low-pass filter is connected with one signal end of the rear-stage EMI filter circuit, and the other end of the rear-stage EMI filter circuit is the signal output end of the main circuit of the 2000W vehicle-mounted inverter.

Further, the 1000W topology circuit comprises a common mode filter M1, a MOS tube Q1, a direct current filter capacitor C1 and a push-pull boosting circuit;

the positive and negative signal input ends of the common mode filter M1 are respectively connected with the positive and negative electrodes of the battery, the positive output end of the common mode filter M1 is connected with the source electrode of the MOS tube Q1, the drain electrode of the MOS tube Q1 is connected with one end of the direct current filter capacitor C1, the other end of the direct current filter capacitor C1 is connected with one end of a resistor R1, and the other end of the resistor R1 is connected with the negative output end of the common mode filter M1;

one end of the direct current filter capacitor C1 is also connected with the positive input end of the push-pull booster circuit, the other end of the direct current filter capacitor C1 is also connected with the positive and negative input ends of the push-pull booster circuit, and the positive and negative output ends of the push-pull booster circuit are connected with the two ends of the rectifying filter capacitor.

Further, the push-pull boost circuit comprises a MOS transistor Q3, a MOS transistor Q4, a high-frequency transformer T1, a resonant inductor L3, a resonant capacitor C3 and a rectifier bridge B1;

the source electrode of the MOS tube Q3 is connected with the source electrode of the MOS tube Q4, the source electrode of the MOS tube Q3 is the positive input end of the push-pull booster circuit, and the center tap of the primary side of the high-frequency transformer T1 is the negative input end of the push-pull booster circuit;

the drain electrode of the MOS transistor Q3 and the drain electrode of the MOS transistor Q4 are respectively connected with two ends of the primary side of the high-frequency transformer T1;

one end of the secondary side of the high-frequency transformer T1 is connected with one end of a resonant inductor L3, the other end of the resonant inductor L3 is connected with one end of a resonant capacitor C3, and the other end of the resonant capacitor C3 is connected with an alternating current input end of a rectifier bridge B1;

the other end of the secondary side of the high-frequency transformer T1 is connected with the other alternating current input end of the rectifier bridge B1, and the positive output end and the negative output end which are connected with the rectifier bridge B1 are respectively connected with two ends of the rectifying filter capacitor.

The 2000W vehicle-mounted inverter main circuit adopts 2 paths of 1000W topological parallel connection, when one path is damaged, the other path can independently operate, and the maximum output power is 1000W. The 2-path 1000W parallel connection is adopted, so that the voltage and current stress of a single component can be reduced, such as an MOS (metal oxide semiconductor) tube, a high-frequency transformer and other devices, and the long-term reliable operation of the inverter can be ensured. By adopting the topological structure, the heat distribution in the inverter can be more uniform, and the heat dissipation design is facilitated. The power supply is applied to a vehicle-mounted high-power inverter power supply, the applied power is effectively improved, and the use is more convenient.

Drawings

Fig. 1 is a circuit diagram of a main circuit of a 2000W onboard inverter according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The first embodiment is as follows: the main circuit of the 2000W vehicle-mounted inverter according to the embodiment is described below with reference to fig. 1, and includes two 1000W topology circuits, a rectifying filter capacitor, an inverter circuit, an LC low-pass filter, and a post-stage EMI filter circuit;

the positive and negative signal input ends of the two 1000W topological circuits are respectively connected with the positive and negative electrodes of the battery, the positive output ends of the two 1000W topological circuits are connected with one end of the rectifying and filtering capacitor, and the negative output ends of the two 1000W topological circuits are connected with the other end of the rectifying and filtering capacitor;

one end of the rectification filter capacitor is also connected with a high-voltage side signal input end of the inverter circuit, and the other end of the rectification filter capacitor is also connected with a low-voltage side signal input end of the inverter circuit;

the signal output end of the inverter circuit is connected with the signal input end of the LC low-pass filter, the signal output end of the LC low-pass filter is connected with one signal end of the rear-stage EMI filter circuit, and the other end of the rear-stage EMI filter circuit is the signal output end of the main circuit of the 2000W vehicle-mounted inverter.

The main circuit topology structure of the 2000W vehicle-mounted inverter described in this embodiment is formed by connecting two 1000W topology circuits in parallel. The input end of the circuit is connected with 2 input common mode filters which are connected in parallel, so that external electromagnetic interference signals are prevented from entering the inverter, and electromagnetic interference signals generated by the inverter are inhibited from radiating outwards; the output of the positive pole of the input common mode filter is connected with an MOS tube, and the function is to prevent the damage of the device caused by the reverse connection of the positive pole and the negative pole of the input end; the output negative electrode of the input filter is connected with a current sampling circuit, the current sampling circuit consists of a high-precision resistance shunt, and the part of the circuit collects bus current to prevent an MOS (metal oxide semiconductor) tube from being burnt due to overlarge current; the sampling circuit is connected with a direct current filter capacitor, and the capacitor has the functions of filtering and energy storage, can filter burr voltage generated by switching action, and can maintain a section of voltage output when the input power supply is suddenly cut off; the filter capacitor is connected with the push-pull boosting circuit, the push-pull MOS tubes are connected in parallel by two paths, the current stress of a single MOS tube can be reduced, the high-frequency transformer adopts a PQ5050 structure transformer, the working frequency is 24k to 100kHz, and the push-pull circuit is beneficial to improving the integral EMC performance of the inverter when working at low frequency; the output of the high-frequency transformer is connected with an LC resonance circuit, so that zero-voltage switching-on and zero-current switching-off of an MOS (metal oxide semiconductor) tube of a push-pull circuit are realized, the switching loss of the MOS tube is reduced, and the efficiency of the whole machine is improved; the rear end of the resonant circuit is provided with a high-frequency rectifying circuit, and a fast recovery diode is selected; all the circuits are connected in parallel by a 1kW circuit, two 1000W circuits are connected in parallel after rectification, a filter capacitor is shared, and the rectification filter capacitor can make the DC bus voltage of the inverter circuit more stable; the inverter circuit adopts a single-phase full-bridge mode, consists of 4 MOS (metal oxide semiconductor) tubes, adopts an SPWM (sinusoidal pulse width modulation) method, and obtains an alternating voltage of 220V/50Hz through an LC (inductance-capacitance) low-pass filter; the output voltage is output by the post-stage EMI filter circuit, and high-frequency electromagnetic waves are restrained from being emitted outwards.

Further, the 1000W topology circuit comprises a common mode filter M1, a MOS tube Q1, a direct current filter capacitor C1 and a push-pull boosting circuit;

the positive and negative signal input ends of the common mode filter M1 are respectively connected with the positive and negative electrodes of the battery, the positive output end of the common mode filter M1 is connected with the source electrode of the MOS tube Q1, the drain electrode of the MOS tube Q1 is connected with one end of the direct current filter capacitor C1, the other end of the direct current filter capacitor C1 is connected with one end of a resistor R1, and the other end of the resistor R1 is connected with the negative output end of the common mode filter M1;

one end of the direct current filter capacitor C1 is also connected with the positive input end of the push-pull booster circuit, the other end of the direct current filter capacitor C1 is also connected with the positive and negative input ends of the push-pull booster circuit, and the positive and negative output ends of the push-pull booster circuit are connected with the two ends of the rectifying filter capacitor.

Further, the push-pull boost circuit comprises a MOS transistor Q3, a MOS transistor Q4, a high-frequency transformer T1, a resonant inductor L3, a resonant capacitor C3 and a rectifier bridge B1;

the source electrode of the MOS tube Q3 is connected with the source electrode of the MOS tube Q4, the source electrode of the MOS tube Q3 is the positive input end of the push-pull booster circuit, and the center tap of the primary side of the high-frequency transformer T1 is the negative input end of the push-pull booster circuit;

the drain electrode of the MOS transistor Q3 and the drain electrode of the MOS transistor Q4 are respectively connected with two ends of the primary side of the high-frequency transformer T1;

one end of the secondary side of the high-frequency transformer T1 is connected with one end of a resonant inductor L3, the other end of the resonant inductor L3 is connected with one end of a resonant capacitor C3, and the other end of the resonant capacitor C3 is connected with an alternating current input end of a rectifier bridge B1;

the other end of the secondary side of the high-frequency transformer T1 is connected with the other alternating current input end of the rectifier bridge B1, and the positive output end and the negative output end which are connected with the rectifier bridge B1 are respectively connected with two ends of the rectifying filter capacitor.

The invention provides a scheme of a 2000W vehicle-mounted inverter which is easy to realize, and on the basis of the existing 1000W technology, the design of the 2000W inverter can be quickly realized only by considering a heat dissipation mode without additionally carrying out design research and development.

With reference to fig. 1, the output positive and negative electrodes of the storage battery are connected with two common mode inductors M1 and M2, and M1 and M2 are connected in parallel; one output end of the anode of the common-mode inductor M1 is connected with an MOS tube Q1, and one output end of the cathode of the common-mode inductor M1 is connected with a sampling resistor R1; one output end of the anode of the common-mode inductor M2 is connected with an MOS tube Q2, and one output end of the cathode of the common-mode inductor M2 is connected with a sampling resistor R2; the MOS tube Q1 is connected with the anode of a direct current filter capacitor C1, and the other end of the sampling resistor R1 is connected with the cathode of the filter capacitor; the MOS tube Q2 is connected with the anode of a direct current filter capacitor C2, and the other end of the sampling resistor R2 is connected with the cathode of the filter capacitor; the positive electrode of the filter capacitor C1 is connected with the input end (the source electrode connection point of Q3 and Q4) of the push-pull circuit 1, and the negative electrode is connected with the center tap of the primary side of the high-frequency transformer T1; the positive electrode of the filter capacitor C2 is connected with the input end (the source electrode connection point of Q5 and Q6) of the push-pull circuit 2, and the negative electrode is connected with the center tap of the primary side of the high-frequency transformer T2; the secondary side of the high-frequency transformer T1 is respectively connected with the AC input of a resonant inductor L3 and a rectifier bridge B1, the other end of the resonant inductor L3 is connected with a resonant capacitor C3, and the resonant capacitor is connected with the AC input of a rectifier bridge B1; the secondary side of the high-frequency transformer T2 is respectively connected with the AC input of a resonant inductor L4 and a rectifier bridge B2, the other end of the resonant inductor L4 is connected with a resonant capacitor C4, and the resonant capacitor is connected with the AC input of a rectifier bridge B2; the output anodes of the rectifier bridges B1 and B2 are connected with the anode of the filter capacitor C5, and the output cathodes of the rectifier bridges are connected with the cathode of the filter capacitor C5; the positive electrode of the filter capacitor C5 is connected with the high-voltage side of the inverter bridge, and the negative electrode of the filter capacitor C5 is connected with the low-voltage side; the output of the inverter bridge is connected with an inductor L5, an inductor L5 is connected with a C6 to form a low-pass filter, and the output of the filter is connected with a common-mode inductor M3.

The 2000W vehicle inverter main circuit topological structure is applied to a vehicle-mounted high-power inverter power supply, is a beneficial improvement on the existing 1000W inverter power supply, and has very important practical significance. On one hand, the research and development period of the 2000W inverter can be shortened, so that the product can be rapidly put into the market; on the other hand, for users, the use of the 2000W inverter can greatly improve the living conditions of drivers and passengers in long-distance driving.

The main circuit topological structure of the 2000W vehicle-mounted inverter is easy to realize, does not need to carry out complex technical development, and has high market competitiveness.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that features described in different dependent claims and herein may be combined in ways different from those described in the original claims. It is also to be understood that features described in connection with individual embodiments may be used in other described embodiments.