Limit current control system of low-voltage motor controller

Abstract

The utility model discloses a limiting current control system for a low-voltage motor controller, which comprises an MCU (Microprogrammed Control Unit) master control module, a plurality of integrated driving modules are connected onto the MCU master control module, and an integrated power module is connected onto the plurality of integrated driving modules; a current detection module responsible for monitoring the working current of the controller power module in real time is integrated in the integrated power module. By adopting the new scheme, the number of peripheral devices can be effectively reduced, and the material cost is reduced; during production, working hours of workers can be reduced, and production efficiency is improved. And high-precision protection: through an accurate current detection and control algorithm, accurate control of the power limit of the motor controller can be realized, and over-current damage caused by overhigh power is avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor controller technical field, concretely is a kind of low-voltage motor controller limit current control system. BACKGROUND

[0002] With the rapid development of new energy electric control technology, low-voltage motor controller plays a vital role in various mechanical equipment and systems. They are responsible for regulating the operation of motor, to ensure that motor works stably and efficiently under various working conditions. However, in practical application, low-voltage motor controller often faces a serious problem: when motor controller runs for a long time in high-power state, due to the increased power consumption of internal components, the controller is easily damaged by overcurrent, which not only affects the normal operation of the equipment, but also may cause serious safety accidents.

[0003] Traditional motor controller overcurrent protection measures, such as setting external current sensor (parallelized constantan wire) sampling, although play a protective role to some extent, single production needs manual parallel insertion of multiple constantan wires to the circuit board, increases worker's working hours, poor consistency, and further causes complex production process, while the precision of constantan wire is low, especially in complex and variable working conditions, these traditional methods often fail to achieve accurate control of motor controller current limit, so as to effectively prevent the occurrence of overcurrent damage.

[0004] Therefore, a low-voltage motor controller limit current control system is proposed. SUMMARY

[0005] The utility model aims at providing a kind of low-voltage motor controller limit current control system to solve the problems raised in the above background technology.

[0006] To achieve the above purpose, the utility model provides the following technical scheme: a kind of low-voltage motor controller limit current control system, including MCU main control module, multiple integrated drive modules are connected on the MCU main control module, multiple integrated drive modules are connected with integrated power module;

[0007] The integrated power module is internally integrated with current detection module responsible for real-time monitoring the working current of controller power module, and the MCU main control module is internally integrated with acquisition module and operation module for converting analog signal of current detection module into digital signal recognizable by MCU.

[0008] Preferably, the acquisition module amplifies, filters and converts analog signal of current detection module through analog switch and ADC circuit, finally obtains digital current data and transmits these data to MCU for processing.

[0009] Preferably, the MCU master module comprises a chip U01, and the model of the chip U01 is XMC1302-T038F0032.

[0010] Preferably, the integrated power module comprises a chip U06, and the pins 1, 2 and 26, 5, 6 and 23, 9, 10 and 20 of the chip U06 are connected to the U, V and W phases of the three-phase motor respectively.

[0011] Preferably, the plurality of integrated drive modules comprise a chip U02, a chip U03 and a chip U04 respectively, and the pins 2 and 3 of the chip U02, the chip U03 and the chip U04 are connected to the pins 17 and 18, 27 and 28, 24 and 23 of the chip U01 respectively.

[0012] Preferably, the pins 5, 6 and 7 of the chip U02 are connected to the pin 3 of the chip U06, the U phase of the motor and the pin 25 of the chip U06.

[0013] The pins 5, 6 and 7 of the chip U03 are connected to the pin 7 of the chip U06, the V phase of the motor and the pin 22 of the chip U06.

[0014] The pins 5, 6 and 7 of the chip U04 are connected to the pin 11 of the chip U06, the W phase of the motor and the pin 19 of the chip U06.

[0015] Preferably, the current detection module comprises an operational amplifier U05, the pin 1 of the operational amplifier U05 is connected to the pin 4 of the chip U01, the pin 8 of the operational amplifier U05 is connected with a capacitor C1, the pin 3 of the operational amplifier U05 is connected with a resistor R2 and connected to the pins 4, 8, 12 and 15 of the chip U06, the pin 2 of the operational amplifier U05 is connected with a resistor R3 and a resistor R5 respectively, and the other end of the resistor R5 is connected to the pin 1 of the operational amplifier U05.

[0016] Compared with the prior art, the utility model has the advantages of:

[0017] The manufacturing cost is reduced: the new scheme can effectively reduce the number of peripheral devices, reduce the material cost; the worker's working hours can be reduced during production, and the production efficiency is improved.

[0018] High-precision protection: through accurate current detection and control algorithm, the accurate control of the power limit of the motor controller can be realized, and the overcurrent damage caused by excessive power is avoided.

[0019] Good consistency: the sampling current sensor is completed by semiconductor production, and the consistency is very strong, and the error of manual parallel connection and copper wire insertion of the original scheme is smaller.

[0020] Improve equipment stability and safety: this method not only can effectively protect the motor controller from over-current damage, but also can improve the stability and safety of the whole system, prolong the service life of the equipment. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic diagram of the control system of the utility model;

[0022] Figure 2 is a structural schematic diagram of the MCU master control module of the utility model;

[0023] Figure 3 is a structural schematic diagram of the integrated drive module of the utility model;

[0024] Figure 4 is a structural schematic diagram of the integrated power module of the utility model;

[0025] Figure 5 is a structural schematic diagram of the current detection module of the utility model;

[0026] Figure 6 is a schematic diagram of the limit power protection of the existing motor controller. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model.

[0028] Please refer to Figures 1-5 The utility model provides a kind of technical scheme: a low-voltage motor controller limit current control system, including MCU master control module, and MCU is monitored in real time by the current detection sensor integrated in it, the working current of controller power module, and current data is transmitted to controller central processing unit in real time.

[0029] Preset current threshold in controller, when the current data collected by current detection sensor reaches the preset threshold of early warning value or limit value, trigger control, protection mechanism. Once current reaches the preset threshold of early warning current, controller automatically adjusts or reduces output power, so as to effectively control current, so that it no longer increases and keeps stable;When controller reaches limit value, MCU automatically stops output power, limits it not to exceed safe range, so as to effectively avoid the occurrence of burning phenomenon. Power adjustment can be realized by adjusting the duty cycle of PWM (pulse width modulation) signal, reducing voltage or current and other ways through frequency conversion mode.

[0030] When the current reaches the warning value or exceeds the limit value and triggers the protection mechanism, the controller should be able to send a fault alarm signal, and can record the time, current and other information of the fault occurrence, facilitating subsequent fault troubleshooting and analysis. The current threshold is set reasonably according to the specific power size of the motor controller, working environment and design requirements, to ensure that the protection mechanism can be triggered in time when the current abnormally rises.

[0031] The MCU master module is connected with a plurality of integrated drive modules, and the plurality of integrated drive modules are connected with an integrated power module;

[0032] The integrated power module is internally integrated with a current detection module responsible for real-time monitoring of the working current of the controller power module, and a high-precision and high-sensitivity current detection sensor such as an alloy resistor is selected to ensure the accuracy of current acquisition. The selection of the integrated packaging position needs to be close to the power module for more accurate sampling.

[0033] The MCU master module is internally integrated with a collection module and an operation module for converting the analog signal of the current detection module into a digital signal recognizable by the MCU.

[0034] Through the current sensing module integrated by the power module, the current of the low-voltage motor controller is monitored in real time, and the current data is processed by the MCU. When the current reaches the preset threshold, the MCU controls the output power of the power module by adjusting the PWM signal to prevent overcurrent. The sampling module converts the analog signal of the current sensor into a digital signal for the MCU to process. If the current exceeds the standard, the alarm unit sends an audible and visual alarm and records the fault information. The whole system ensures the safe operation of the motor controller through precise current monitoring and power adjustment.

[0035] As shown in Figure 1 : The collection module amplifies, filters and converts the analog signal of the current detection module through an analog switch and an ADC circuit, finally obtains digital current data and transmits these data to the MCU for processing.

[0036] As shown in Figure 2 : The MCU master module includes a chip U01, and the model of the chip U01 is XMC1302-T038F0032. The MCU master module is the core processing unit of the whole controller, responsible for receiving the data of the current sensor, making current threshold judgment, and controlling the power adjustment of the power module. It is also responsible for the management of the fault alarm and recording system.

[0037] The MCU receives the analog signal of the current sensing module through the internal ADC (analog-to-digital converter) or external sampling module, and converts it into a digital signal for processing. When the current of the integrated power module reaches or exceeds the preset threshold, the MCU triggers the protection mechanism and controls the output power of the power module by adjusting the duty cycle parameter of the PWM signal.

[0038] As shown in Figure 4 : the integrated power module includes chip U06; the 1, 2 and 26, 5, 6 and 23, 9, 10 and 20 pins of chip U06 are connected to the U, V and W phases of the three-phase motor respectively. The power module is the core component of the motor controller, responsible for converting the input power into the driving power required by the motor. It adjusts the output power according to the instructions of the MCU through the integrated drive part. The power module contains power semiconductor devices (such as MOSFET) inside, which adjusts the output voltage and current by controlling the conduction and turn-off of these devices. The MCU controls the duty cycle of the power module through the PWM signal, thereby achieving precise control of the output power.

[0039] As shown in Figure 3 : the multiple integrated drive modules respectively include chip U02, chip U03 and chip U04; the 2 and 3 pins of chip U02, chip U03 and chip U04 are connected to the 17 and 18, 27 and 28, 24 and 23 pins of chip U01 respectively. SDH21263 can drive N-type power MOSFET and IGBT and other high-voltage power devices, and through the input of logic signals by the MCU, the chip can control the conduction and turn-off of the power devices, thereby meeting the power output requirements of the circuit. Built-in protection functions: VCC undervoltage protection and high-low side input signal interlock protection, etc.

[0040] As shown in Figure 3 : the 5, 6 and 7 pins of chip U02 are connected to the 3 pin of chip U06, the U phase of the motor and the 25 pin of chip U06;

[0041] The 5, 6 and 7 pins of chip U03 are connected to the 7 pin of chip U06, the V phase of the motor and the 22 pin of chip U06;

[0042] The 5, 6 and 7 pins of chip U04 are connected to the 11 pin of chip U06, the W phase of the motor and the 19 pin of chip U06.

[0043] As shown in Figure 5 : the current detection module includes operational amplifier U05, the 1 pin of operational amplifier U05 is connected to the 4 pin of chip U01, the 8 pin of operational amplifier U05 is connected with capacitor C1, the 3 pin of operational amplifier U05 is connected with resistor R2 and connected to the 4, 8, 12 and 15 pins of chip U06, the 2 pin of operational amplifier U05 is connected with resistor R3 and resistor R5 respectively, the other end of resistor R5 is connected to the 1 pin of operational amplifier U05. Integrated in the power module, the current sensing module is responsible for real-time monitoring of the working current of the motor controller power module, and converting the current data into electrical signals for transmission to the MCU.

[0044] The current sensor usually adopts high-precision and high-sensitivity elements such as constantan wire, alloy resistance or digital current sensor. These elements will collect current data, which is amplified by the ADC circuit and then enters the MCU. The MCU obtains current data by measuring these changes.

[0045] The alarm unit is responsible for issuing a fault alarm signal when the current exceeds the overcurrent value, and recording the time, current and other information of the fault occurrence.

[0046] When the MCU detects that the current exceeds the overcurrent value, it will trigger the alarm unit. The alarm unit issues a warning to the operator through an audible and visual alarm signal (such as a buzzer, LED indicator light, etc.). At the same time, the alarm unit is also responsible for recording fault information, including the time of fault occurrence, current value, etc. These information can be transmitted to the host computer or remote monitoring system through a communication interface (such as RS485, CAN, etc.).

[0047] Working principle: Chip U01 is XMC1302-T038F0032 of Infineon Company, core: ARM Cortex-M0, application field: power conversion, factory automation, building automation, transportation and household appliances, etc. It is especially suitable for high-performance processing embedded control applications such as motor control and LED lighting. It provides various peripheral interfaces such as ADC, PWM, timer, etc. to meet various application requirements. It supports advanced control algorithms such as non-inductive FOC (magnetic field oriented control).

[0048] The current sensor sampling of the integrated power unit is sampled through the ADC of P2.7 port, with a sampling accuracy of 12 bits, thereby providing higher current sampling accuracy.

[0049] The integrated current sensor signal is led out from pins 15 and 16 of U06 CCM360N10 integrated chip and converted by the amplifier.

[0050] The signal sampled by the current sensor enters the MCU through the amplification circuit. The MCU finds the corresponding current value of the current sensor resistor through table lookup method, thereby obtaining the current inside the integrated power module.

[0051] When the current value reaches the preset current, the MCU reduces the duty cycle of PWM through algorithm, that is, adjusts the pulse signal of pins 17 (UH), 18 (UL); 27 (VH), 28 (VL), 23 (WH), 24 (WL) of the MCU; This pulse signal drives the integrated power drive module SDH21263.

[0052] When the current value reaches the overcurrent, the MCU adjusts the duty cycle of PWM to 0 through algorithm, thereby stopping the drive of the motor.

[0053] Integrated drive module: SDH21263 of Silex is used as a half-bridge drive circuit for N-type power MOSFET high-voltage power device. It has multiple protection functions built-in: overcurrent protection, overvoltage protection, undervoltage protection, high-low side input signal interlock protection, high-side floating offset voltage, etc.

[0054] As shown in U02, U03, U04 chips drive one upper and lower half-bridge respectively, and three SDH21263 can realize the drive of UVW three-phase motor. PIN2 and PIN3 of U02, U03, U04 are connected to the PWM output end of MCU, and the opening and closing of the power module are adjusted according to the duty cycle required by MCU, to realize the control of the motor.

[0055] PIN5, PIN6, PIN7 of U02, U03, U04 are connected to the gate G signal of the lower bridge, the U (or V or W) end of the motor and the gate G signal of the upper bridge respectively; PIN5 and PIN7 are adjusted to open and close according to the duty cycle of the input signal of PIN2 and PIN3, and then the drive of the integrated power module is realized, that is, opening or closing.

[0056] Integrated power module: CCM360N10 is used as an N-type power MOSFET module in integrated power module U06, which is the first integrated 18-core MOSFET full-bridge module. The chip is designed for motor control and other applications, and integrates split gate trench technology, with low RDS(ON), low gate charge, low gate resistance and extremely low thermal resistance, etc. It also integrates internal current collection, which can monitor the current of the chip through external circuit to realize the protection of the limit power.

[0057] CCM360N10 chip usage:

[0058] The U, V, W phase pins of the three-phase motor output are connected to the chip PIN1 and PIN2 (U phase), PIN5 and PIN6 (V phase), PIN9 and PIN10 (W phase) respectively;

[0059] Gate control pins: G1 and G6 correspond to the U phase lower and upper bridge gate; G2 and G5 correspond to the V phase lower and upper bridge gate, G3, G4 correspond to the W phase lower and upper bridge gate;

[0060] Source sampling pins: S4, S5, S6 are connected to the motor phase lines W, V, U respectively;

[0061] Source sampling pins: S1, S2, S3 are connected to PIN15 (current sensor R1 end);

[0062] The power pins of the chip are VDD and VSS.

[0063] The current collection pins are PIN15 and PIN16, which are used for sampling the internal current of the chip, and through an amplification circuit, corresponding voltage values can be sampled, and the MCU can calculate the internal current of the chip according to the voltage values; in combination with the specification book and the curve of the chip, the limit power protection is carried out on the chip, so as to prevent the power module from being burnt out.

[0064] Although the embodiments of the utility model have been shown and described, it can be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A low voltage motor controller limit current control system comprising of MCU master module, characterized in that: The MCU master module is connected with a plurality of integrated drive modules, and the integrated drive modules are connected with an integrated power module. The integrated power module is internally integrated with a current detection module responsible for real-time monitoring of the working current of the controller power module, and the MCU master module is internally integrated with an acquisition module and an operation module for converting analog signals of the current detection module into digital signals recognizable by the MCU.

2. A low voltage motor controller limit current control system as claimed in claim 1, characterized in that: The acquisition module amplifies, filters and converts analog signals of the current detection module through an analog switch and an ADC circuit, finally obtains digital current data and transmits the data to the MCU for processing.

3. A low voltage motor controller limit current control system as claimed in claim 1, characterized in that: The MCU master module comprises a chip U01, and the model of the chip U01 is XMC1302-T038F0032.

4. A low voltage motor controller limit current control system as claimed in claim 1, characterized by: The integrated power module comprises a chip U06. The pins 1, 2 and 26, 5, 6 and 23, and 9, 10 and 20 of the chip U06 are connected with U, V and W phases of the three-phase motor respectively.

5. A low voltage motor controller limit current control system as claimed in claim 4, characterized in that: The integrated drive modules comprise a chip U02, a chip U03 and a chip U04 respectively. The pins 2 and 3 of the chips U02, U03 and U04 are connected with the pins 17 and 18, 27 and 28, and 24 and 23 of the chip U01 respectively.

6. A low voltage motor controller limit current control system as claimed in claim 5, characterized in that: The pins 5, 6 and 7 of the chip U02 are connected with the pin 3 of the chip U06, the U phase of the motor and the pin 25 of the chip U06. The pins 5, 6 and 7 of the chip U03 are connected with the pin 7 of the chip U06, the V phase of the motor and the pin 22 of the chip U06. The pins 5, 6 and 7 of the chip U04 are connected with the pin 11 of the chip U06, the W phase of the motor and the pin 19 of the chip U06.

7. A low voltage motor controller limit current control system as claimed in claim 6, characterized in that: The current detection module comprises an operational amplifier U05, the pin 1 of the operational amplifier U05 is connected with the pin 4 of the chip U01, the pin 8 of the operational amplifier U05 is connected with a capacitor C1, the pin 3 of the operational amplifier U05 is connected with a resistor R2 and connected with the pins 4, 8, 12 and 15 of the chip U06, the pin 2 of the operational amplifier U05 is connected with a resistor R3 and a resistor R5 respectively, and the other end of the resistor R5 is connected with the pin 1 of the operational amplifier U05.

Images