Imagine, you are designing servo, computerized numerical control (CNC) or the next power level that the robot uses. Below this kind of circumstance, power level is inverter of three-phase of low-pressure dc feed, voltage limits arrives for 12 VDC 60 VDC, rated power is less than 1 KW. This are rated voltage is covered use at motor of batteries power supply normally the limits of the batteries voltage in system or system of motor of low-pressure dc feed. Additional, you may satisfy such requirement even: In this product need not be designed below the circumstance of level of additional and cooling power. It must as far as possible small, in order to satisfy the requirement of target application process, of course it needs low cost.
So, below this kind of circumstance, think up an acceptable solution to design to satisfy this hypothesis (although the demand is very high) inverter, satisfy above to ask thereby.
Accordingly, before beginning to define designation power to class, electric current detects and protect circuit, it is very important that the reference of 48V/500W three-phase inverter that considers to introduce drive of servo of intelligent grid driver is designed, this reference design is extremely practical and understand easily.
Should consult the design used the IC with compositive height to realize small size requirement, include 3 to have the drive of 100% half bridge grid that take sky comparing job. Optional source / collect electric current to differ to 2 A from 50 MA. VDS is passed feeling can have come true to shed protection, prevent attaint power level and motor. Because wrong pulse width modulation is configured, VGS handclasp function can protect power level to avoid suffer shoot wear.
Graph 1: Spread level of feed servo power continuously
Graph 1 in of driver of servo of low-pressure dc feed cover module to have very big effect to systematic performance, affect a design to consider a factor.
Add driver of half bridge grid to be passed in order to realize VDS through detecting breakdown feeling and soft close, can compose builds dovish system. These functions allow grid driver system to detect typical flow too or short circuit incident. Do time of dead band of the implementation below the condition that can not adding additional electricity to travel feeling or hardware circuit to insert so, ensure MCU cannot provide wrong drive signal thereby, this may cause power level or motor causes damage because of short circuit.
Element of a consideration is to optimize efficiency, blast off in order to reduce radiator and radiate (the cost of EMI) and switch speed. Through 100 V Chan Qiao or transistor of effect of half bridge field (FET) grid driver realizes these functions to need additional active and passive component, this meeting adds stock detailed account (BOM) cost and printed circuit board dimension, connect regular meeting to reduce the flexibility of the parameter such as intensity of modification grid drive at the same time. When analysing systematic efficiency, report circulates the electrification road, FET that has low DS(on) and low grid charge can realize sudden switch, affect systematic efficiency performance thereby. Normally, systematic design personnel hopes to achieve power level the efficiency of 99% .
To realize loss the smallest successive phase current detects, consulted the online spreader of 1mΩ is used in the design. Choice resistance is mixed as precision between efficiency eclectic. Be not the main challenge that online amplifier faces segregation type is a system those who use is wide in all modular voltage (0V comes 80V) , this designs voltage of medium billabong full span to be ±30Arms) for ±30mV(design considering this reference. With 48V? ? in all modular voltage photograph is compared, this is a small-sized signal. Accordingly, need is had big in all modular voltage limits and extremely tall DC and AC in all modular low-key electric current passes feeling amplifier. As a result of low shunt-wound impedance, have additional and compositive fixed gain and the amplifier of 0 deflection to conduce to further reduce systematic cost, ensure the electric current with accurate height is measured at the same time.
100-VDC step-down manostat can produce the course intermediate from dc input, for grid driver and laden dot power supply. Power level needs efficient job to be heated up in order to decrease oneself, such ability satisfy industrial environment temperature (it is 85°C) normally. Considering this, this means the integrated circuit that uses in the system to need to support higher temperature, because electronic equipment always can appear a few temperature rise (heat up oneself) circumstance.
The referenced design of servo driver uses PMSM motor to be in 0 to 500W output power falls have a test. Motor load by measure result implement control, if pursue,2 are shown.
Graph 2: The test of level of motor drive power is installed
Have intelligent grid driver to consult the 48V/500W three-phase inverter of the design is used at servo driver, revealed how to design have low BOM number, inphase electric current to detect, breakdown diagnostic function and efficient compact model level of hardware protection power. This is the implementation of driver of grid of DRV8530100V three-phase intelligence that passes heart state apparatus, the 80V that this driver has step-down manostat and INA240 to have the PWM that increase to control function, low / high side, two-way, 0 drift, electric current passes feeling amplifier, this can realize low n to optimize – level of power of voltage dc feed. The more and detailed information that uses about systematic performance and IC, consult reference designs a guideline please.