Electrophoresis apparatus power supply system

Abstract

The electrophoresis apparatus power supply system comprises a main circuit module, an auxiliary power supply module, an MCU intelligent control module, a man-machine interaction module, a communication module, a timing programming module and a protection module. The invention belongs to the technical field of electrophoresis apparatus power supply systems, and particularly relates to an electrophoresis apparatus power supply system.

Description

Technical Field

[0001] This invention belongs to the technical field of electrophoresis apparatus power supply systems, specifically referring to an electrophoresis apparatus power supply system. Background Technology

[0002] Current electrophoresis apparatus power supplies generally adopt a standardized architecture of rectification and filtering + PWM control (e.g. Figure 1 It has the following defects:

[0003] Outdated operation: physical buttons, no touchscreen or voice interaction;

[0004] Functional limitations: Does not support multi-time period programmable output (voltage / current / power switching on demand);

[0005] Weak security: The protection mechanism is simple, with no real-time dynamic monitoring or remote alarms;

[0006] Poor compatibility: Narrow input voltage range (typically only supports 220V). Summary of the Invention

[0007] The technical problem to be solved by this invention is that the power supply of existing electrophoresis instruments is outdated in operation, has limited functions, weak safety and poor compatibility.

[0008] To achieve the above functions, the technical solution adopted by the present invention is as follows: an electrophoresis apparatus power supply system, comprising:

[0009] Main circuit module: It adopts a forward topology and integrates a power factor correction (PFC) unit to convert AC input into adjustable DC output.

[0010] Auxiliary power supply module: Connected to the main circuit module, it is used to convert the DC power output from the main circuit into multiple low-voltage DC power sources.

[0011] MCU intelligent control module: Electrically connected to the main circuit module, used to control the output parameters of the main circuit module.

[0012] Human-machine interaction module: electrically connected to the MCU intelligent control module, including a touch screen unit and a voice broadcast unit. The touch screen unit is used to receive user parameter setting instructions, and the voice broadcast unit is used to broadcast the device operating status.

[0013] Communication module: Electrically connected to the MCU intelligent control module for remote control.

[0014] Timing programming module: Integrated into the MCU intelligent control module, it is used to store and execute multiple timing instructions, which include voltage, current or power parameters for different time periods.

[0015] Protection module: Monitors the current / voltage signals of the main circuit module in real time and triggers the MCU intelligent control module to shut down the output when an abnormality occurs.

[0016] Preferably, the auxiliary power supply module includes:

[0017] The forward buck converter draws power from the main circuit module and generates multiple isolated low-voltage outputs through the control chip and transformer.

[0018] A low-dropout linear regulator unit, connected to a forward buck converter unit, is used for secondary voltage regulation of the isolated output;

[0019] The enable control unit, controlled by the MCU intelligent control module, controls the on / off state of the specified low-voltage output through optocouplers and transistor circuits.

[0020] Preferably, the main circuit module includes:

[0021] The AC input unit integrates EMI filter circuitry and surge absorber, and can be connected to 85-220V AC power.

[0022] The rectifier and filter unit converts AC power into DC power;

[0023] The PFC unit includes a PFC control IC and a feedback circuit, which improves the power factor by adjusting the duty cycle of the MOSFET.

[0024] The half-bridge soft-switching output unit, including a control chip, transformer, and MOSFET group, is used to convert the DC power corrected by the PFC unit into the output voltage / current required for the electrophoresis experiment.

[0025] Preferably, the PFC control IC includes:

[0026] The feedback input terminal receives the PFC feedback signal output from the subsequent stage, which is then filtered by the filtering circuit before being input.

[0027] The output detection terminal is used to detect whether the output of the PFC unit reaches the preset value. When the value is met, the indicator light is triggered to indicate that the PFC is working normally.

[0028] At the PWM output, the conduction state of the MOSFET is controlled by adjusting the duty cycle;

[0029] The peripheral circuit is equipped with a fast turn-off circuit consisting of resistors and diodes.

[0030] Preferably, the communication module adopts a 485 bus architecture and includes:

[0031] The 485 converter chip connects to the MCU via a digital isolation chip;

[0032] Terminal matching resistor and anti-interference inductor;

[0033] The A / B pins connect to the host computer to enable remote control.

[0034] Preferably, the protection module includes:

[0035] The current detection circuit transmits signals to the MCU through a shunt resistor and a comparator.

[0036] The voltage detection circuit transmits signals to the MCU through voltage divider resistors and a comparator.

[0037] When any signal exceeds the threshold, the MCU shuts down the main circuit and triggers a voice alarm.

[0038] Preferably, in the half-bridge soft-switching output unit:

[0039] The output enable terminal of the control chip is controlled by the MCU through a transistor;

[0040] Two PWM signals alternately drive the secondary MOSFET of the transformer, and the output is rectified and filtered.

[0041] Preferably, the timing programming module supports setting multiple sets of independent parameters, each set of parameters including start time, duration and corresponding voltage / current / power values.

[0042] The beneficial effects achieved by adopting the above structure in this invention are as follows:

[0043] 1. The use of a touch screen to replace traditional buttons, along with voice prompts, makes operation more intuitive and convenient, reducing the difficulty of operation for experimenters.

[0044] 2. Remote control is achieved through 485 communication, and the integrated timed programming function supports multi-stage parameter settings to meet the needs of automated experiments.

[0045] 3. By using the PFC power factor correction architecture, the power factor is improved to above 0.9, reducing energy consumption.

[0046] 4. It adopts a high-precision ADC acquisition and closed-loop control algorithm, and the output voltage and current accuracy reaches ±0.1%, which meets the requirements of precision electrophoresis experiments.

[0047] 5. The main circuit supports 4-channel output and can be expanded to 7 channels, balancing performance and complexity. Attached Figure Description

[0048] Figure 1 This is a structural circuit diagram of the existing technology;

[0049] Figure 2 This is a circuit diagram of the main circuit module in an embodiment of the present invention;

[0050] Figure 3This is a circuit diagram of the half-bridge soft-switching output unit according to an embodiment of the present invention;

[0051] Figure 4 This is a circuit diagram of the auxiliary power supply module according to an embodiment of the present invention;

[0052] Figure 5 This is a circuit diagram of the current detection circuit in the protection module of this invention.

[0053] Figure 6 This is a voltage detection circuit diagram in the protection module of an embodiment of the present invention;

[0054] Figure 7 This is a circuit diagram of the communication module in the protection module of an embodiment of the present invention;

[0055] Figure 8 This is a circuit diagram of the MCU intelligent control module according to an embodiment of the present invention;

[0056] Figure 9 This is a circuit diagram of the ADC module external to the MCU intelligent control module in an embodiment of the present invention;

[0057] Figure 10 This is an overall circuit diagram of an embodiment of the present invention. Detailed Implementation

[0058] I. Specific Implementation of the Main Circuit Module

[0059] like Figure 2 As shown, the main circuit module adopts a forward topology and integrates a power factor correction (PFC) unit. Its core function is to convert an 85-220V AC input into an adjustable DC output. The specific circuit implementation is as follows:

[0060] 1. AC input unit, connected to an external 85-220V AC power supply, with a fuse and surge absorber (RT1-RT3) connected in series, followed by an EMI filter circuit (including CX1, L1, R2, R11, R5, CX2, CY1, CY2). The surge absorber and the EMI filter circuit are connected by wires to filter out high-frequency interference and surges from the power grid, and output purified AC power.

[0061] 2. Rectifier and filter unit

[0062] The input terminal is connected to the output terminal of the EMI filter circuit of the AC input unit. The AC power is converted into DC power through the rectifier bridge (B1). A filter capacitor (such as C6) is connected in parallel to the output terminal of the rectifier bridge to realize the conversion of pulsating DC to smooth DC.

[0063] 3. PFC unit,

[0064] ① Components: PFC control IC (U2), peripheral circuits

[0065] Pin 1 (Feedback Input): Connected to the PFC feedback signal (PFC_FB) output from the subsequent stage. The signal is processed by a filter circuit composed of resistor R21 and capacitor C11 before being input. It is used to collect the PFC output voltage in real time and provide a basis for closed-loop control.

[0066] Pin 2 (Output Detection Terminal): Connected to the PFC output terminal via voltage divider resistors R25 and R33 to detect whether the output reaches the preset value. If it does, the voltage divider turns on transistor Q5, which in turn triggers optocoupler U3 (input terminal turned on). The optocoupler output terminal drives transistor Q17 to turn on. The collector voltage of Q17 turns on Q16 through R24 and R115 (base voltage divider bias resistors of Q16), ultimately triggering the indicator light to stay on.

[0067] Pin 3 (Error Amplifier Output): Connects to the RC filter circuit composed of R35, C13, and R12, used to stabilize the error amplification signal and ensure the stability of PFC control.

[0068] Pin 4 (Input of overcurrent protection comparator): The PFC circuit current is acquired through shunt resistors R39 and R40, and the current signal is converted into a voltage signal input through resistor R9 to realize overcurrent protection detection.

[0069] Pin 5 (Zero Current Check Pin): Connected to pin 7 of transformer T5, used to detect the moment when the inductor current crosses zero, and to optimize the PWM control timing.

[0070] Pin 6 (Ground): Connect to the circuit ground to ensure the IC reference potential is stable.

[0071] Pin 7 (PWM output): Directly connected to the gate of MOSFET Q3, the conduction state of Q3 is controlled by outputting PWM high and low levels; the gate of Q3 is also connected to R22 and R29 (voltage divider bias resistors) to ensure stable gate voltage. This pin can change the conduction time of Q3 by adjusting the PWM duty cycle, thereby increasing the PFC output voltage.

[0072] Pin 8 (Power Input): Connect to filter capacitor C10 to provide a stable power supply for the IC and ensure the normal operation of U2.

[0073] ② Peripheral circuit:

[0074] Discharge circuit: It consists of resistor R28 and diode VD3. One end is connected to the source of Q3 and the other end is grounded, which accelerates the release of gate charge of Q3 when it is turned off and reduces switching losses.

[0075] Voltage divider bias resistors: R25, R33 (base voltage divider for Q5), R22, R29 (gate voltage divider for Q3), R24, R115 (base voltage divider for Q16), etc., to ensure the stability of the operating point of each transistor and MOSFET.

[0076] 4. Half-bridge soft-switching output unit

[0077] like Figure 3 As shown, the input terminal is connected to the output terminal of the PFC unit. The core is the control chip U1. Its pins 1 and 8 (output enable terminals) are connected to the base of transistor Q6 through resistors R26 and R31. The collector of Q6 is connected to pin 24 of the MCU (U9) to realize the MCU's control of the output enable of U1. Pins 2 and 4 are connected to pins 14 and 11 of the PWM signal generation chip U6 to receive the basic PWM timing. Pins 5 and 7 (output terminals) are connected to the gates of MOSFETs Q2 and Q18 through resistors R7 and R23, respectively. The sources of Q2 and Q18 are connected in series with Zener diodes CR1 and CR2 (to prevent... (Gate overvoltage), and connected to the drain via bootstrap capacitors C2 and C8 and resistors R37 and R38; the drains of Q2 and Q18 are connected to the primary winding of transformer T3, and the secondary winding of T3 is coupled to the primary windings of transformers T1 and T2 respectively; the output terminal of the secondary winding of T1 is connected to rectifier diodes D2 to D5 (full-bridge rectification), and the rectified output terminal is connected in series with inductor L2 and filter capacitor E3 to output an adjustable DC voltage; the output terminal of the secondary winding of T2 is connected to rectifier diodes VD4 to VD7, and the rectified output terminal is connected in series with shunt resistors R42 and R45, and then connected to pin 5 of comparator IC1 to form a current detection signal path.

[0078] II. Specific Implementation of the Auxiliary Power Supply Module

[0079] like Figure 4 As shown, a dual-transistor forward converter, low-voltage converter, and intelligent control circuit are used to provide a stable low-voltage power supply for various ICs, microcontrollers, and peripheral devices. The specific structure is as follows:

[0080] 1. Forward buck converter

[0081] The main circuit VIN input (VIN network label before D1) is processed by a dual-transistor forward buck converter circuit. On the left side of the forward converter (to the left of transformer T4), the peripheral circuit configuration of the control chip U8 is as follows: Pin 1 is grounded via capacitor C54; Pin 2 is the sampling voltage input pin, consisting of a voltage divider network composed of R54, R78, R84, and R91; Pin 3 is the voltage feedback input terminal, with R101 and R102 used for current shunting, R95 for current limiting, and C37 as a filter capacitor; Pin 4 allows setting the switching frequency of Q7 by changing the resistance value of R93; Pin 6 is used to control Q7 to turn off and output PWM to adjust the duty cycle; Pin 8 is the soft-switching setting terminal, and changing the values ​​of R174 and C52 controls the switch start state.

[0082] The transformer T4 has three outputs on the right side: Output 1 is a 20V to 12V to 5V module; Output 2 is a 12V module, where V1, V2, and U5 are linear step-down ICs, with external capacitors acting as filters, resistors acting as current limiters, and diodes acting as reverse connection protection; In Output 3, diode VD15 prevents excessive reverse voltage, R69 and C51 are used to improve the circuit frequency response to prevent oscillation, R64 and R70 are bias resistors, L7 is a filter inductor, and E16 and E17 are filter capacitors. This output 12V (DC) is used for external connection and to power chip U22.

[0083] 2. Low dropout linear voltage regulator unit

[0084] The chip U22 functions as a 12V to 5V converter. In its peripheral circuit, C29 is the input filter capacitor, R167 and R121 are enable pin bias resistors, pin 4 is connected to R166 to set the chip frequency, pin 5 collects the voltage on R168 as output feedback, pin 6 is the common terminal and is grounded through R165, C33 and C32, and pin 8 is the switch control pin, which can control the duty cycle of the step-down circuit composed of VD23, L12 and C49.

[0085] 3. Enable control unit

[0086] Two external terminals (LED, LED2) are connected. The remaining circuit is a microcontroller control circuit used to control whether to output 5V voltage. EN_5VOUT is connected to the microcontroller pin. When the microcontroller outputs a high level, Q13, U23, and Q19 conduct, and pin 1 of both LEDs is grounded, causing the LEDs to light up. When the output is low, the LEDs are off. R104 and R170 limit current, R169 is a pull-down resistor, and C42 is used to accelerate the turn-off of Q13. PWM_FAN is also connected to the microcontroller. When the microcontroller outputs PWM, Q12, U4, and Q8 conduct, and the FAN interface outputs PWM. This part of the circuit uses resistor current limiting, optocoupler isolation, and diode reverse connection protection design.

[0087] III. Specific Implementation of the MCU Intelligent Control Module

[0088] like Figure 8As shown, the MCU (U9) pin 485_RE1 is isolated and connected to the MAX485ED 485 converter chip via the optocoupler TLP181GB-S, thereby controlling the shutdown of 485 communication. In the peripheral circuit of MAX485ED, the VOB and VIA pins of the digital isolation chip ADUM1201AR are connected to the MCU's 485_TX1 and 485_RX1. The use of the isolation chip ADUM1201AR can effectively prevent the microcontroller from being burned out. The 485 pins A1 and B1 are used to connect to the host computer. Among them, R153, R163, R152, and R157 are current-limiting resistors, R150, R161, and R164 are pull-up resistors (to pull the level high), R155 is the 485 termination matching resistor, L9 and L10 are used to prevent external interference, and D6 and D7 are used for voltage regulation.

[0089] An external high-precision ADC module is used because the accuracy of the ADC conversion module inside the microcontroller is not high enough.

[0090] IV. Specific Implementation of the Human-Computer Interaction Module

[0091] 1. Touchscreen unit

[0092] It connects to the corresponding pins of the MCU via the SPI interface, receives voltage, current, and power parameters input by the user, and displays the real-time output status.

[0093] 2. Voice broadcast unit

[0094] It connects to the TX and RX pins of the MCU via the UART interface, receives command signals from the MCU, and announces statuses such as "startup successful" and "overcurrent protection".

[0095] V. Specific Implementation of the Communication Module

[0096] like Figure 7 As shown, the MCU pin 485_RE1 is isolated and connected to the MAX485ED 485 converter chip via the optocoupler TLP181GB-S to control the shutdown of 485 communication.

[0097] The ADUM1201AR digital isolation chip uses pins VOB and VIA to connect to the MCCU's 485_TX1 and 485_RX1 pins. The ADUM1201AR isolation chip is used to prevent the microcontroller (MCU) from being burned out. Pins A1 and B1 of the 485 circuit connect to the host computer. Resistors R153, R163, R152, and R157 are current-limiting resistors. Resistors R150, R161, and R164 are pull-up resistors (to pull the voltage high). R155 is the 485 termination matching resistor. L9 and L10 prevent external interference. D6 and D7 provide voltage regulation, enabling remote data transmission and control.

[0098] VI. Specific Implementation of the Timed Programming Module

[0099] Integrated into the MCU's internal Flash memory, it connects to the real-time clock module via the MCU's timer pin to store multiple sets of user-defined timing instructions (including start time, duration, voltage / current / power parameters). When the trigger time arrives, the MCU automatically calls the corresponding parameters to adjust the output.

[0100] VII. Specific Implementation of the Protection Module

[0101] 1. Current detection circuit

[0102] like Figure 5 As shown, the main circuit input (with the same network labels connected) is connected to the MCU's ADC_IOUT pin via two comparators GS8592-SR. High-precision current output and fast dynamic response are achieved through software control algorithms. Circuit logic: If the main circuit current is too high, the output LINAR_GDRIVE (with the same network labels connected!) is generated by two operational amplifiers, causing device Q1 to turn off and the entire main circuit to disconnect. R147 and R151 are current-limiting resistors, and R158 and C102 form a feedback network, similarly to U14B.

[0103] 2. Voltage detection circuit

[0104] like Figure 6 As shown, the main circuit input (with the same network label connected) is connected to the MCU's ADC_VOUT pin via two comparators GS8592-SR. Circuit logic: If the main circuit voltage is too high, the output LINAR_GDRIVE is generated after two operational amplifiers, device Q1 is turned off, and the entire main circuit is disconnected. The circuit includes resistor current limiting, capacitor filtering, a feedback network composed of R142, R143, C78, ​​and C81, and a diode overvoltage protection circuit.

[0105] When the current / voltage exceeds the threshold, the comparator outputs a high level to the MCU, and the MCU immediately turns off the output of the half-bridge soft switching unit through Q6 and triggers an alarm from the voice module.

[0106] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. An electrophoresis apparatus power supply system characterized by comprising: The main circuit module includes a forward topology structure and a combined power factor correction (PFC) unit for converting an AC input into an adjustable DC output. The auxiliary power module is connected with the main circuit module and is used for converting the DC output of the main circuit into multiple low-voltage DC outputs. The MCU intelligent control module is electrically connected with the main circuit module and is used for controlling the output parameters of the main circuit module. The human-computer interaction module is electrically connected with the MCU intelligent control module and includes a touch screen unit and a voice broadcast unit. The communication module is electrically connected with the MCU intelligent control module and is used for realizing remote control. The timing programming module is integrated in the MCU intelligent control module and is used for storing and executing multiple timing instructions including voltage, current or power parameters in different time periods. The protection module monitors the current / voltage signals of the main circuit module in real time and triggers the MCU intelligent control module to shut down the output when an abnormality occurs.

2. The power supply system for electrophoresis apparatus according to claim 1, wherein: The auxiliary power module includes: The forward step-down unit takes power from the main circuit module, generates multiple isolated low-voltage outputs through a control chip and a transformer, and controls the on-off of the specified low-voltage output through an optocoupler and a transistor circuit. The low-dropout linear regulation unit is connected with the forward step-down unit and is used for performing secondary voltage regulation on the isolated output. The main circuit module includes:

3. The power supply system for electrophoresis apparatus according to claim 1, wherein: The AC input unit is integrated with an EMI filter circuit and a surge absorber and is connected with 85-220V AC power. The rectifier filter unit converts AC power into DC power. The PFC unit includes a PFC control IC and a feedback circuit and improves the power factor by adjusting the duty cycle of a MOS tube. The half-bridge soft switching output unit includes a control chip, a transformer and a MOS tube group and is used for converting the DC power corrected by the PFC unit into the output voltage / current required by the electrophoresis experiment. The PFC control IC includes:

4. The power supply system for electrophoresis apparatus according to claim 1, wherein: The feedback input end is connected with the PFC feedback signal of the output in the later stage and inputs after being filtered by a filter circuit. The output detection end is used for detecting whether the output of the PFC unit reaches a preset value and triggers an indicating lamp to turn on to indicate that the PFC is working normally when the preset value is reached. The PWM output end controls the conduction state of the MOS tube by adjusting the duty cycle. The peripheral circuit is provided with a fast shutdown loop composed of a resistor and a diode. The MCU intelligent control module integrates a high-precision ADC unit, collects the output current signal and voltage signal of the main circuit in real time, and realizes dynamic response through a closed-loop algorithm.

5. The power supply system for electrophoresis apparatus according to claim 1, wherein: The communication module adopts a 485 bus architecture and includes:

6. The power supply system for electrophoresis apparatus according to claim 1, wherein: The 485 conversion chip is connected with the MCU through a digital isolation chip. The terminal matching resistor and anti-interference inductor are connected with the A / B pins to realize remote control through a host computer. The protection module includes: The current detection circuit transmits a signal to the MCU through a shunt resistor and a comparator.

7. The power supply system for electrophoresis apparatus according to claim 1, wherein: The voltage detection circuit transmits a signal to the MCU through a voltage dividing resistor and a comparator. When any signal exceeds a threshold value, the MCU shuts down the main circuit and triggers a voice alarm. In the half-bridge soft switching output unit, ​ 8. The power supply system for electrophoresis apparatus according to claim 1, wherein: ​ The output enable end of the control chip is controlled by the MCU through a transistor; Two-way PWM signals alternately drive the transformer secondary MOS tube, and output after rectification and filtering.

9. The power supply system for electrophoresis apparatus according to claim 1, wherein: The timing programming module supports setting multiple groups of independent parameters, and each group of parameters includes a start time, a duration, and corresponding voltage / current / power values.

10. The power supply system for electrophoresis apparatus according to claim 1, wherein: The digital isolation chip is a magnetic isolation type or an optical coupling isolation type, and the 485 conversion chip integrates a failure protection function.

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