Half-bridge module induction type gate driving power supply based on four layers of PCBs
Technical Field
The invention belongs to the field of wireless electric energy transmission, relates to the design of a power supply of a gate drive circuit of a power semiconductor device, and particularly relates to a half-bridge module induction type gate drive power supply based on a four-layer PCB.
Background
An Insulated Gate Bipolar Transistor (IGBT) half-bridge module driving circuit usually needs an isolated power supply, and the power supply must meet design indexes such as isolated voltage, volume and weight.
At present, an isolation type driving power supply is mainly isolated by adopting a power frequency transformer, a high-frequency transformer, non-contact electric energy transmission and other modes. Although the power frequency transformer has strong insulating capability and is easy to improve the isolation voltage, the power frequency transformer has large volume and heavy weight. The high-frequency transformer is the mainstream isolation way of the commercial driving power supply at present, but compared with the common commercial driving chip, such as the HCPL-3120 chip of Avago company or the IR2110 chip of IR company, the high-frequency transformer has much larger volume and much heavier weight. For a multi-level converter widely used in high-voltage and high-power occasions, as mentioned in the application and implementation of a cascading multi-level converter without a power frequency transformer under a coal mine, the isolation voltage of a driving power supply needs to be dozens of kilovolts or even hundreds of kilovolts. Such high isolation voltages are difficult to achieve with high frequency transformer approaches.
Different from a transformer isolation mode, the isolation is carried out by adopting a non-contact electric energy transmission mode, so that very high isolation voltage can be easily obtained. However, at present, the transmitting coil and the receiving coil in the inductive non-contact power transmission are mostly wound by conducting wires by hand, and extra installation space is needed. In order to reduce the coil volume, researchers have printed the transmit coil and the receive coil separately on different pcb (printed Circuit board) boards. However, the design method using the discrete multiple PCBs often requires a larger installation space than the high frequency transformer.
In order to effectively solve the above problems, the present invention provides a half-bridge module induction type gate driving power supply based on a four-layer PCB, and the specific contents of the invention are as follows.
Disclosure of Invention
Aiming at the problems in the prior art, the invention designs a gate driving power supply with high isolation voltage, small volume and light weight by adopting an inductive non-contact electric energy transmission technology based on a multilayer PCB, namely provides a half-bridge module inductive gate driving power supply based on a four-layer PCB, and solves the problems of low isolation voltage, large volume and heavy weight of the half-bridge module driving power supply.
In order to achieve the purpose, the invention adopts the technical scheme that:
the utility model provides a half-bridge module induction type gate pole drive power supply based on four layers of PCB, half-bridge module induction type gate pole drive power supply be four layers of PCB circuit board structure, from last to being top layer, intermediate level 1, intermediate level 2, bottom down in proper order. The half-bridge module induction type gate driving power supply comprises a transmitter and two receivers, and the transmitter and the receivers are electrically isolated from each other. The transmitter consists of a transmitting circuit and a transmitting coil, and the receiver consists of a receiving circuit and a receiving coil; the input of the transmitter is 24V direct current voltage, the output of the receivers is +/-15V direct current voltage, and the two receivers respectively provide two paths of isolated power supply voltage to supply power for driving circuits of upper bridge arm switches and lower bridge arm switches of the IGBT half-bridge module.
And the transmitting circuit and the two receiving circuits are arranged on the top layer of the four-layer PCB. The receiving coil, the transmitting coil and the other receiving coil are sequentially arranged on an intermediate layer 1, an intermediate layer 2 and a bottom layer of the four-layer PCB, and the receiving coil, the transmitting coil and the other receiving coil are all spiral copper coils carved on the PCB. The transmitting coil on the middle layer 2 provides electric energy for the two receiving coils, the three coils are in electrical contact with each other, isolation is carried out by means of a PCB insulating layer, and the isolation voltage can reach 30 kV/mm. The transmitting coil and the receiving coil are electrically connected with corresponding circuits arranged on the top layer through different through holes respectively. The four-layer PCB circuit board on correspond the position all be equipped with the via hole, the via hole runs through whole PCB board, the central point that receiving coil and transmitting coil were located to the via hole position puts and the spiral copper coil outside.
The transmitting circuit comprises a class E amplifier and a transmitting coil compensating circuit. Electric energy is input by a 24V direct current power supply, and is transmitted to the transmitting coil by the transmitting coil compensating circuit after high-frequency inversion of the class-E amplifier. The transmitting coil compensation circuit adopts an LCL compensation mode, so that the input reactive power can be reduced, and the current of the transmitting coil is kept constant.
The receiving circuit comprises a receiving compensation circuit, a rectifying circuit, a filter circuit, a voltage stabilizing circuit and a driving unit. The high-frequency alternating current electric energy is received by the receiving coil, converted to +/-15V direct current voltage through the receiving compensation circuit, the rectifying filter circuit and the voltage stabilizing circuit, and sent to the driving unit to provide stable power supply. The receiving compensation circuit is a series capacitor, and a series compensation mode is adopted, so that the reactive power of a receiving side can be compensated, and the stability of the circuit is improved. The rectification circuit is an uncontrollable full-bridge rectification circuit and is used for converting high-frequency alternating current into direct current. The filter circuit is a parallel capacitor. The voltage stabilizing circuit adopts LM7815 and LM7915 chips, can export 15V direct current voltage.
The volume of the driving power supply depends on the size of the PCB and the height of components in the circuit, and the weight depends on the weight of the four layers of PCBs and the weight of the top layer patch element.
The invention has the beneficial effects that:
(1) by adopting the inductive non-contact power transmission technology, no electric contact exists between the transmitting coil and the receiving coil. The coils are carved on different layers of the PCB, and the driving power supply can obtain the isolation voltage of 30 kV/mm.
(2) Based on the multilayer PCB technology, all components (a transmitting circuit, a receiving circuit, a transmitting coil and a receiving coil) of the driving power supply are highly integrated on a four-layer PCB, so that the coils are prevented from occupying extra installation space, and the volume of the driving power supply is greatly reduced. The length and width of the invented driving power supply depend on the designed PCB size, and the height depends on the thickness of the four-layer PCB plus the height of the top-layer component. The top component can be a patch element with small volume, so that the overall height is not high. The design enables the invented driving power supply to be miniaturized, and high integration of the half-bridge module and the driver thereof is convenient to realize.
(3) The weight of the invented driving power supply depends on the weight of the four-layer PCB board and the weight of the top-layer patch element, and the light weight is realized.
(4) One transmitting coil is provided with two receiving coils which can respectively supply power to the upper bridge arm switch and the lower bridge arm switch of the half-bridge module in an isolated manner, so that the material cost is saved.
Drawings
Fig. 1 is a side view of the overall structure of the inventive driving power supply.
Fig. 2 is a schematic diagram of the overall structure of the inventive driving power supply.
Fig. 3 is a transmitter circuit diagram.
Fig. 4 is a circuit diagram of the receiver 1.
Detailed Description
The following detailed description of the embodiments and the working principle of the present invention will be made with reference to the accompanying drawings.
As shown in fig. 1, the inventive half-bridge modular induction gate driving power supply is highly integrated on a PCB. The PCB comprises four layers, a transmitting circuit and a receiving circuit are arranged on the top layer of the PCB, and a receiving coil 1, a transmitting coil and a receiving coil 2 are respectively carved on the middle layer 1, the middle layer 2 and the bottom layer of the PCB. The through holes penetrate through the whole PCB and are respectively connected with different coils and corresponding circuits. As can be seen from fig. 1, the volume of the invented driving power supply depends on the size of the PCB board and the height of the components in the circuit, which facilitates miniaturization and light-weight.
As shown in fig. 2, the inventive driving power source is composed of a transmitting circuit, a transmitting coil, a pair of receiving circuits, and a pair of receiving coils. The transmitting circuit and the receiving circuit are arranged on the top layer of the PCB, and the receiving coil 1, the transmitting coil and the receiving coil 2 are respectively carved on the middle layer 1, the middle layer 2 and the bottom layer of the PCB. The transmitting circuit in the top layer is connected with the transmitting coil in the middle layer 2 through two via holes, and the receiving circuit 1 and the receiving circuit 2 in the top layer are respectively connected with the receiving coil 1 in the middle layer 1 and the receiving coil 2 in the bottom layer through other via holes. The transmitting coil and the receiving coil are insulated from each other by means of the PCB board, and the insulation voltage can be as high as 30 kV/mm. The transmitting coil and the receiving coil are both spiral copper coils, have consistent radius and are coaxially distributed. Parameters such as the number of turns of the coil, the line width, the radius and the like can be designed according to specific application. The input of the driving power supply is 24V direct current voltage, and the output is two paths of isolated +/-15V direct current voltage. The driving unit can be placed on the top layer of the PCB, and the driving power supply provides stable voltage for the driving unit to guarantee reliable work. The working principle of the driving power supply is based on an induction type non-contact electric energy transmission technology, specifically, 24V direct current voltage is converted into high-frequency alternating current through a transmitting circuit, the high-frequency alternating current flows through a transmitting coil to excite a spatial high-frequency alternating magnetic field, so that high-frequency induced current is induced in a receiving coil, and the high-frequency induced current is converted through the receiving circuit to output +/-15V direct current voltage.
As shown in fig. 3, the transmitter consists of a class E amplifier, a compensation circuit and a transmitting coil. The 24V direct current voltage provided by the power supply is inverted by the class-E amplifier to obtain high-frequency alternating current, and the high-frequency alternating current is input and transmitted by the transmitting side LCL compensation circuitRadiating the coil to create a spatial high frequency magnetic field. E amplifier composed of DC inductor L
1MOSFET type switch tube, driver thereof and resonant capacitor C
1Output inductance L
2And an output capacitor C
2And (4) forming. The coupling coefficient of the transmitting coil and the receiving coil is low, and a proper compensation circuit is needed to reduce reactive power and loss. The transmitting side compensation circuit adopts LCL compensation mode and consists of series inductor L
3Parallel capacitor C
3And coil self-inductance L
pAnd (4) forming. Inductor L is required to be ensured during LCL compensation circuit design
3Self-inductance L with transmitting coil
pEqual in order to achieve a constant transmit coil current value. Inductor L
3And a capacitor C
3Should satisfy
Where f is the switching frequency.
As shown in fig. 4, the receiver 1 is composed of a receiving coil 1, a series compensation capacitor, a rectifying circuit, a filter circuit and a voltage stabilizing circuit. The circuit structure of the receiver 2 is identical to that of the receiver 1, and the description thereof is omitted. In the electric energy transmission process, after receiving the high-frequency alternating current, the receiving coil 1 finally outputs +/-15V direct current voltage through the series compensation capacitor, the rectification filter circuit and the voltage stabilizing circuit. The compensation mode at the receiving side is series capacitance compensation, and the compensation capacitor C
4Self-inductance L with receiving coil
sShould satisfy
The circuit is in a resonance state, reactive power of a receiving side is compensated, and the stability of the circuit is improved. The rectification circuit adopts an uncontrollable full-bridge rectification circuit, high-frequency alternating current is converted into direct current, an IN4007 type surface mounted diode can be selected as a rectification diode, the maximum reverse breakdown voltage is 1000V, and the working current is 1A. The filter circuit is a parallel capacitor C
fAnd a 22 muF/50V patch capacitor can be selected. The voltage stabilizing circuit adopts LM7815 and LM7915 chips to realize the output of +15V and-15V voltages. Capacitor C on two sides of LM7815
2And C
4Can respectively select 0.33 muF and 0.1 muF chip capacitors and a voltage stabilizing diode D
5Optional IN4001 type paster diodeA tube. Capacitor C on two sides of LM7915
3And C
5Can respectively select 2.2 muF and 1 muF chip capacitors and a voltage stabilizing diode D
6An IN4001 type chip diode is optionally used.
The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.