High-power multipurpose high-precision precise adjustable light source

Abstract

The invention provides a high-power multipurpose high-precision precise adjustable light source, which comprises a high-power precise adjustable power supply, the high-power precise adjustable power supply comprises an inverter unit and a voltage-stabilized power supply, commercial power is converted into direct current through voltage stabilization of the voltage-stabilized power supply and then is accessed to the inverter unit, and an IGBT in the inverter unit is connected with the inverter unit under the control of a controller. A precisely controlled voltage is generated to be connected with the lamp; the controller is an FPGA (Field Programmable Gate Array) controller, and the FPGA controller is internally provided with a circuit interface circuit communicated with the upper computer, a data merging and distributing latch circuit for latching, merging and distributing received data, and a PWM (Pulse Width Modulation) generating circuit for generating PWM waveforms with corresponding duty ratios according to voltage amplitude, frequency and phase numerical values provided by instructions of the upper computer. According to the invention, the PWM waveform with the corresponding duty ratio is generated according to the voltage amplitude, frequency and phase value provided by the instruction of the upper computer, and the PWM signal controls the four IGBTs of the inversion unit to generate an accurate high-power voltage source, thereby achieving the precise control of the light source.

Description

Technical Field

[0001] The invention relates to the field of high-power adjustable light sources, in particular to a high-power multi-purpose high-precision and precise adjustable light source. Background Art

[0002] In many fields such as the lithium battery industry, color sorting equipment, chromaticity, turbidity detection, etc., high-power precision adjustable light sources are important basic components. Existing technologies generally use external adjustable light sources to supplement the detection device, or use built-in non-adjustable light sources to supplement the light. Although the external light source has sufficient power, the adjustment accuracy is poor. Summary of the invention

[0003] The present invention aims at the disadvantage of poor regulation accuracy of current high-power light sources and provides a high-power multi-purpose high-precision precision adjustable light source.

[0004] The technical solution adopted by the present invention to achieve its technical purpose is: a high-power multi-purpose high-precision precision adjustable light source, including a high-power precision adjustable power supply, the high-power precision adjustable power supply includes an inverter unit and a voltage-stabilizing power supply, the AC power is converted into direct current by the voltage-stabilizing power supply and then connected to the inverter unit, and the IGBT in the inverter unit generates a precisely controlled voltage to connect the lamp under the control of the controller; the controller is an FPGA controller, and the FPGA controller is equipped with: a circuit interface circuit for communicating with a host computer, a data merging and distributing latch circuit for latching, merging and distributing received data, and a PWM waveform with a corresponding duty cycle generated according to the voltage amplitude, frequency, phase and other values ​​provided by the host computer instructions.

[0005] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the PWM generation circuit includes a DDS module, a sine wave generation module, a modulated triangle wave module, a waveform selection module, an amplitude modulation module, a carrier triangle wave module, and a comparator module; The voltage amplitude, frequency and phase values ​​transmitted by the host computer through the circuit interface circuit are combined and distributed in the data latch circuit to generate a phase control signal, a frequency control signal, an amplitude control signal and a waveform selection signal; the phase control signal, the frequency control signal and the external clock signal are input into the DDS module, and the output of the DDS module generates a sine modulation wave and a triangular modulation wave through a sine wave generation module and a modulated triangular wave module respectively. Under the control of the waveform selection signal, the waveform selection module selects one of the sine modulation wave and the triangular modulation wave as a modulation wave output, and under the control of the amplitude control signal, the amplitude modulation module performs amplitude modulation on the selected modulation wave, and the external clock signal is input into the carrier triangular wave module to generate a triangular carrier, and the triangular carrier and the modulation wave output a PWM signal through a comparator.

[0006] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the host computer controls the inverter unit to output voltage according to the following formula: u0=A(sin(ωt)+1)+C Where: u0 is the output voltage of the inverter unit, A is the amplitude of the AC component, ω is the output AC angular frequency, and C is the amplitude of the DC component.

[0007] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the circuit interface circuit adopts a "data string" serial interface circuit.

[0008] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the FPGA controller is also provided with: a PLL clock generating circuit, a voltage display circuit and a synchronization signal generating circuit.

[0009] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the inverter unit includes a bridge arm circuit composed of four IGBTs, and the four IGBTs 60N60FD1 are driven by four PWM signals generated by the PWM generation circuits in the FPGA controller respectively.

[0010] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the PWM generation circuit in the FPGA controller generates a PWM signal which is added to the gate of the IGBT after being isolated by an optical coupler.

[0011] Furthermore, in the above-mentioned high-power multi-purpose high-precision precision adjustable light source: the PWM generation circuit in the FPGA controller generates PWM, and when it is added to the gate of the IGBT, a gate resistor R2 is also connected in series, and also includes a diode D1 and a resistor R3. The diode D1 is connected in parallel at both ends of the resistor R2, the anode of the transistor D1 is connected to the gate of the IGBT, and the resistor R3 is arranged between the gate and the source of the IGBT.

[0012] Furthermore, the above-mentioned high-power multi-purpose high-precision precision adjustable light source also includes a current acquisition circuit, which acquires the voltage of a current-sensing resistor, and the current-sensing resistor includes a group of high-power precision sampling resistors connected in series to the anode or cathode of the output end of the voltage-stabilized power supply.

[0013] In the present invention, a PWM waveform with a corresponding duty cycle is generated according to the voltage amplitude, frequency and phase values ​​provided by the host computer instruction. The PWM signal controls the inverter unit including four IGBTs to generate an accurate sinusoidal voltage signal to achieve precise control of the light source.

[0014] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Attached Figure 1 This is a block diagram of the lamp control principle of the present invention; Attached Figure 2 This is a block diagram of the internal structure of FPGA used in the present invention; Attached Figure 3 It is the principle diagram of the inverter circuit of the present invention; Attached Figure 4 The present invention is a current detection circuit; Attached Figure 5 The auxiliary power supply circuit and the driving circuit of the present invention; Attached Figure 6 is the output sinusoidal voltage waveform of embodiment 1 of the present invention; Attached Figure 7 This is a block diagram of the PWM generation module in the FPGA used in the present invention. DETAILED DESCRIPTION

[0016] Embodiment 1, this embodiment is a high-power multi-purpose high-precision precision adjustable light source for lamps used in many fields such as lithium battery industry, color sorting equipment, chromaticity, turbidity detection, etc., which can be precisely adjusted by controlling the input power of the lamp to achieve light precision adjustment, such as Figure 1 The power supply circuit of the lamp of this embodiment is shown in FIG. 1 , which precisely controls the 220VAC mains power supply. The power supply process is as follows: Figure 1 As shown in the figure, the 220VAC mains electricity is converted into direct current after passing through the voltage stabilizing circuit, which is 400VDC in this case, and then passes through Figure 3 The inverter unit shown in the figure is inverted into a high voltage in the shape of an AC, and its waveform is as follows Figure 6 In this embodiment, the output voltage of the inverter unit is: u o =A(M*sin(ωt)+1+D) (M+D≤1)m——AC componentd——DC component Where M (0≤M≤1) is the AC modulation, D (0≤D≤1) is the DC modulation, and M+D≤1. If there is a “-” before d, the DC component decreases, and if there is a “+” before d, the DC component increases. A is the amplitude of the AC voltage. If the DC voltage is U d , then A=U d / 2. n is half of the triangular carrier amplitude. Figure 6 As shown, if d is "0" and m is n, then the expression of the output voltage is u0=200(sin(ωt)+1) Because (-1≤sin(ωt)≤1), the output voltage is 0≤u0≤400V, and the output is a sine wave with a maximum value of 400V and a minimum value of 0. If m=0, d=n, the output voltage is a DC voltage of u0=400V. In the expression, n is the number of digital control bits. If the triangular carrier and the sine wave are 10 bits, n is half of the carrier, that is, n=511. The triangular carrier here is used to generate PWM. The generated PWM signal is used to drive four IGBTs. The four IGBTs are connected into an H bridge. The IGBT signals on the diagonal are the same, and the IGBTs on the same bridge arm are complementary. According to the "area equivalence principle" of PWM modulation, the voltage of the corresponding waveform can be output to drive the lamps.

[0017] In fact, the inverter unit outputs voltage according to the following formula: u0=A(sin(ωt)+1)+C Here C is the DC component amplitude, C = A (1 + D) In this embodiment, the inverter unit is as follows Figure 3 As shown, 4 IGBTs are controlled by PWM signals generated by FPGA. The internal structure diagram of FPGA is as follows Figure 2 As shown: The lighting control power supply uses the FPGA chip EP4CE6E22C8 with superior performance and high cost performance as the core controller. The FPGA is composed of circuit interface circuit, data merging and allocation latch circuit, multiple signal generation and PWM generation circuit, PLL clock generation circuit, voltage display circuit and synchronization signal generation circuit. The serial interface circuit is responsible for communication with the host computer. The data merging and allocation latch circuit first latches the received serial data. The serial interface circuit sends 11 groups of data "data strings" at a time, represented by D1-D11. Its format starts with FF and ends with AA, with 9 groups of data in the middle, representing different instructions. That is, D1 is FF, D11 is AA, D2 and D3 represent frequency, D4 and D5 represent AC component amplitude, D6 and D7 represent DC component amplitude, D8 and D9 represent the starting position of the waveform, D10 represents the instruction, 0 is start and stop, 1 is waveform, and 2-4 is spare.

[0018] The role of data merging is that since serial data is 8 bits per byte, some large data requires two 8-bit data to be merged and then sent to the corresponding control unit.

[0019] In this embodiment, PWM generation is generated by a plurality of signal generators and a PWM generation circuit. Figure 7As shown: it includes a DDS module, a sine wave generation module, a modulated triangle wave module, a waveform selection module, an amplitude modulation module, a carrier triangle wave module, and a comparator module; the voltage amplitude, frequency, and phase values ​​transmitted by the host computer through the circuit interface circuit are combined and allocated to the latch circuit to generate a phase control signal, a frequency control signal, an amplitude control signal, and a waveform selection signal; the phase control signal, the frequency control signal, and the external clock signal are input into the DDS module, and the output of the DDS module generates a sine wave and a modulated triangle wave through the sine wave generation module and the modulated triangle wave module respectively. Under the control of the waveform selection signal, the waveform selection module selects one from the sine wave and the modulated triangle wave as the modulated wave output, and under the control of the amplitude control signal, the amplitude modulation module performs amplitude modulation on the modulated wave, and the external clock signal is input into the carrier triangle wave module to generate a carrier triangle wave, and the carrier triangle wave and the modulated wave output PWM signals through the comparator.

[0020] The function of the multiple signal generation and PWM generation circuit is to generate sine and triangular waveforms, and generate PWM waveforms with corresponding duty cycles according to the voltage amplitude, frequency, phase and other values ​​provided by the host computer command, with a carrier frequency of 10kHz. After passing through the drive circuit, the corresponding voltage of the IGBT output is directly controlled. The principle of multiple signal generation is as follows Figure 7 As shown in the figure, the main component for generating various signals is the DDS waveform generator. The waveform data of the sine wave and the triangle wave are stored in the memory inside the FPGA. The frequency and phase of the waveform are controlled by DDS, and the amplitude control is achieved through an internal multiplier. A comparator is used to generate a PWM waveform with the amplitude modulated waveform and the triangle carrier.

[0021] The function of the PLL clock generation is to generate accurate multiple clock signals and provide a serial interface, namely the PWM generation circuit. The function of the voltage display circuit is to provide the voltage output of the host computer display. The function of the synchronization signal generation circuit is to output a synchronization signal corresponding to the waveform position so as to synchronously start the camera to take pictures.

[0022] Drive circuit such as Figure 5 As shown, a photocoupler TLP250 with strong driving capability is used, and each IGBT corresponds to one TLP250. Since the same bridge arm of the IGBT cannot share the same ground, an isolated power supply module AC / DC is used to convert 220V AC into 12V DC.

[0023] The inverter unit is the main circuit that generates AC power under the control of the controller. Figure 3As shown: it uses IGBT60N60FD1, and the maximum current reaches 60A. Therefore, this embodiment is a high-power adjustable light source. The city power is stabilized by the voltage stabilizing circuit to form a 400VDC DC power supply input from the interface P1 and enters the inverter bridge. Under the control of the PWM signal output by the FPGA controller, according to the timing and switching time indicated by the host computer, the direction of the DC power supply is from the L pole of the voltage stabilizing power supply, that is, the anode left upper arm - inductor L1 - capacitor C1 - right lower arm - cathode. Since the output voltage is "AC-shaped DC voltage", the right lower arm IGBT is always turned on.

[0024] In this embodiment, a current acquisition circuit for detecting the current of the main circuit, that is, the inverter circuit, is also included. Figure 4 As shown, the current acquisition is composed of 4 high-power precision sampling resistors, which are sent to the conversion module after 358 conditioning, and the collected current is converted into 4-20mA output. The current acquisition circuit is used to collect the output voltage of the voltage-stabilized power supply. Since it is a 400VDC DC output, its power can be obtained by collecting its current, that is, the power of the adjustable light source. For lamps, the power of the lamps corresponds to the brightness of the light source. Therefore, the signal can be fed back to the host computer, where the collected current data is processed and the duty cycle of the PWM signal is adjusted to adjust the output power. Figure 4 As shown in the figure, in the current acquisition circuit: operational amplifier U1B constitutes a comparator, U1A is a signal follower, and M1 is a conversion module that converts the voltage signal into a 4-20mA current signal. 4-20mA is a current signal that reflects the current size of the lamp, and the purpose is to prevent signal attenuation.

Claims

1. A high-power multi-purpose high-precision precision adjustable light source, including a high-power precision adjustable power supply, the high-power precision adjustable power supply includes an inverter unit and a voltage-stabilized power supply, the city power is converted into direct current by the voltage-stabilized power supply and then connected to the inverter unit, the IGBT in the inverter unit generates a precisely controlled voltage to connect to the lamp under the control of a controller; the characteristics are: The controller is an FPGA controller, which is equipped with: a circuit interface circuit for communicating with a host computer, a data merging and allocating latch circuit for latching, merging and allocating received data, and a PWM generating circuit for generating a PWM waveform with a corresponding duty cycle according to the voltage amplitude, frequency and phase values ​​provided by the host computer instructions.

2. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 1, characterized in that: The PWM generation circuit includes a DDS module, a sine wave generation module, a modulation triangle wave module, a waveform selection module, an amplitude modulation module, a carrier triangle wave module, and a comparator module; The host computer sends the secondary value, frequency and phase value through the interface circuit through the data The amplitude, frequency and phase values ​​transmitted by the host computer through the interface circuit are combined and distributed in the data latch circuit to generate a phase control signal, a frequency control signal, an amplitude control signal and a waveform selection signal; the phase control signal, the frequency control signal and the external clock signal are input into the DDS module, and the output of the DDS module is respectively passed through the sine wave generation module and the modulated triangle wave generation module to generate a sine modulation wave and a triangle modulation wave. Under the control of the waveform selection signal, the waveform selection module selects one of the sine modulation wave and the triangle modulation wave as the modulation wave output, and under the control of the amplitude control signal, the amplitude modulation module modulates the modulation wave, and the external clock signal is input into the carrier triangle wave module to generate a triangle carrier, and the triangle carrier and the modulation wave output a PWM signal through a comparator.

3. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 2 is characterized by: The output voltage of the inverter unit is direct current or direct current with an alternating current waveform, and the host computer controls the inverter unit to output voltage according to the following formula: u0=A(sin(ωt)+1)+C Where: u0 is the output voltage of the inverter unit, A is the amplitude of the AC voltage, ω is the output AC angular frequency, and C is the amplitude of the DC component.

4. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 1, characterized in that: The interface circuit adopts a "data string" serial interface circuit.

5. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 2 is characterized by: The FPGA controller is also provided with: a PLL clock generating circuit, a voltage display circuit and a synchronous signal generating circuit.

6. The high-power, multi-purpose, high-precision, precision-adjustable light source according to any one of claims 1 to 5, characterized in that: The inverter unit comprises a bridge arm circuit composed of four IGBTs, and the four IGBTs 60N60FD1 are driven by four PWM signals generated by PWM generation circuits in the FPGA controller respectively.

7. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 6, characterized in that: The PWM generation circuit in the FPGA controller generates a PWM signal which is added to the gate of the IGBT after being isolated by an optical coupler.

8. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 7, characterized in that: The PWM generating circuit in the FPGA controller generates PWM which is added to the gate of the IGBT, and is also connected in series with a gate resistor R2, and also includes a diode D1 and a resistor R3. The diode D1 is connected in parallel at both ends of the resistor R2, the anode of the transistor D1 is connected to the gate of the IGBT, and the resistor R3 is arranged between the gate and the source of the IGBT.

9. The high-power, multi-purpose, high-precision, precision-adjustable light source according to claim 8, characterized in that: It also includes a current acquisition circuit, which acquires the voltage of a current-sensing resistor. The current-sensing resistor includes a group of high-power precision sampling resistors connected in series to the anode or cathode of the output end of the voltage-stabilized power supply.

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