IRPT5051A

PD 6.070A PRELIMINARY IRPT5051 POWIRTRAIN™ Integrated Power Stage for 15 hp Motor Drives · 15 hp (11kW) power output · 380 - 480VAC; 50/60 Hz · Available as complete system or sub-system assemblies Power Assembly · · · · · · 3-phase rectifier bridge 3-phase ultrafast IGBT inverter NTC temperature sensor Pin-to-base plate isolation 2500 Vrms Easy-to-mount package Case temperature range -20°C to 95°C operational Driver-Plus Board · Capacitor filter with precharge current limit · Isolated gate drive circuits · On-board local power supply for gate driver and capacitor precharge control · MOV surge suppression at input · Isolated inverter current feedback · Short circuit, earth/ground fault, over-temperature protection · Input and output terminals; optional external brake · Control interface connector 380 - 480 V 3-phase input POWIRTRAIN driver power supply IRPT5051C variable frequency/ voltage AC motor POWIRTRAIN isolated PWM signals isolated power supply isolated feedback PWM signal generator feedback processing keyboard External Control Functions Figure 1. The IRPT5051C POWIRTRAIN within a motor control system Revised 11/5/96 page 1 IRPT5051 System Description The IRPT5051C POWIRTRAIN provides the complete power conversion function for a 15hp (11kW) variable frequency AC motor controller. It contains a 3-phase input rectifier, DC link capacitor, 3-phase IGBT inverter, isolated gate drive circuits, shutdown protection, isolated trip and current feedback signals, and capacitor pre-charge function. Terminal blocks fitted to the POWIRTRAIN allow for end-user input and output connections. Output power is pulse-width modulated (PWM) 3-phase, variable frequency, variable voltage controlled by externally generated user-provided PWM logic input signals, which control the inverter stage – IGBT switching. The PWM input signal terminals and the output feedback signals are optically isolated from the power circuit. Figure 1 is a block diagram of the IRPT5051C POWIRTRAIN within an AC motor control system. Figure 4 shows the functions and architecture of the IRPT5051C. The IRPT5051C combines a lower Insulated Metal Substrate (IMS) power board, containing the power semiconductors and a thermistor, with the Driver-Plus Board. The power assembly is designed to be mounted to a heat sink. Figure 2 shows the IRPT5051A power assembly. The Driver-Plus Board interfaces electrically to the IRPT5051A power assembly via soldered connector pins. All external connections to the POWIRTRAIN are made to terminal blocks on the Driver-Plus Board (figure 3.) The IRPT5051C POWIRTRAIN offers several benefits to the motor control manufacturer: · It eliminates component selection, design layout, interconnection, gate drive, local power supply, thermal sensing, current sensing, and protection. · It provides committed power semiconductor losses and junction temperatures. · Parts inventory is reduced. · Gate drive and protection circuits are designed to closely match the operating characteristics of the power semiconductors. This allows power losses to be minimized and power rating to be maximized to a greater extent than is possible by designing with individual components. · Optimized layout for performance and efficiency is provided. · Low inductance system reduces noise and snubber requirements. · Manufacturing assembly is greatly simplified. [POWIRTRAIN specifications and ratings are given for system input and output voltage and current, power losses and heat sink requirements over a range of operating conditions. POWIRTRAIN system ratings are verified by IR in final testing.] inverter. A thermistor is included in the inverter section for thermal sensing. The power stage is designed to minimize inductance in the power path and reduce noise during inverter operation. The power level interfaces to the Driver-Plus Board through solder pins, minimizing assembly and alignment. The power assembly mounts to a heat sink with five screw mount positions, one in each corner and a fifth near the center to insure good thermal contact between the IMS and the heat sink. Wide copper traces on the IMS insure low impedance interconnects for the power components. Figure 2. IRPT5051A Power Assembly The IRPT5051D Driver-Plus Board Figure 3 is a photograph of the IRPT5051D Driver-Plus Board containing the driver, sensing and protection functions. Figure 4 provides detailed functional block diagrams of the IRPT5051D. The switching power supply delivers a nominal 18V DC output, referenced to the negative DC bus, N. This feeds the gate drive, relay control and under voltage (UV) circuits, which are optically isolated from the control input section, and therefore require their own local power source. The gate drive circuits deliver on/off gate drive signals to the IGBTs' gates, corresponding with input PWM control signals IN1 through IN6. The PWM gate normally allows the input PWM control signals to pass to the input opto-isolators of the gate drive circuits. The conduction periods of the inverter switches essentially mimic those demanded by the PWM input signals. During power-up and power-down, or in the event of overcurrent (OI) or overtemperature (OT), the latch inhibits the PWM The IRPT5051A IMS Power Assembly The IRPT5051A Power Assembly, shown in figure 2, employs surface-mount 1600V rated D2Pak input rectifiers and surfacemount SMD-10 1200V IGBT Co-pack switches for the output page 2 IRPT5051 gate, deactivating the gate drive circuits and shutting off the inverter. The relay control circuit delivers an on/off signal via an opto-isolator to the relay driver which controls the relay (K1). The relay contact is open during power-up, inserting the resistor R in series with the DC bus capacitor and limiting the capacitor charging current. In normal operation, the relay contact is closed. If the AC line voltage falls below 300V or if one input phase is lost, or if the DC line voltage falls to less than 82% of the peak line voltage, the relay contact opens. The UV circuit senses the voltage of the local power supply, and sends a signal via an opto-isolator to the latch in the event of undervoltage. The UV circuit normally activates the latch only during power-up and power-down, preventing the IGBTs from being turned on when the local power supply voltage is too low for proper IGBT switching. The current signal processing circuit receives inputs from current transformers connected in series with the input lines and the DC bus capacitor. The output of the current signal processing circuit, IFB, is essentially an isolated replica of the inverter input current. An isolated current feedback signal, IFB, is provided as an output of the IRPT5051A. If the inverter current exceeds the trip level of 65A, IFB also activates the latch. The thermistor activates the latch if the temperature of the IMS substrate exceeds a set level. The 15V isolated power supply used to power the IRPT5051 should be the same as the one for the PWM gnereation, otherwise the protection functions will be disabled. Figure 3. IRPT5051D Driver-Plus Board page 3 IRPT5051 INPUT RECTIFIER P IMS POWER BOARD Q1 THERMISTOR Q3 OUTPUT INVERTER Q5 Q2 Q4 Q6 RS T RP P RT1 RT2 N G1 E1 G2 E2 G3 E3 G4 E4 G5 E5 G6 E6 U VW RS T RP P RT1 RT2 N G1 E1 G2 E2 G3 E3 G4 E4 G5 E5 G6 E6 U VW PRECHARGER DC LINK CAPS LINE SENSE CT RELAY CONTACT (K1) CAP SENSE SWITCHING POWER SUPPLY +18 GATE DRIVER CIRCUITS OPTO ISOLATION RELAY CONTROL AND U/V OPTO ISOLATION CT CT CURRENT SIGNAL PROCESSING RELAY DRIVER AND RELAY COIL (K1) LATCH OI, OT, UV CT PWM GATE 16 GND R S T POWER TB CN6A 19 20 17 15 7 89 SIGNAL TB 12 13 14 18 1 2 3 4 5 6 N PU V W +15 COM -15 IFB CN5 BUS SFT KIFB RIPPLE CHG RESET OI OT UV IN1 IN2 IN3 IN4 IN5 IN6 CN5 Driver -Plus Board Driver- Plus Board POWER TB CN6B Figure 4. IRPT5051C Basic Architecture page 4 IRPT5051 Specifications PARAMETER Input Power Voltage Frequency Input Current VALUES 380V -15% to 480V +10%, 3-phase 50 - 60Hz 40A rms 300 A peak 0 - 480V rms 15hp (11kW) 25A rms CONDITIONS Output Power TA = 40°C, Rth SA = 0.075 °C/W 10 ms half-cycle non-repetitive surge defined by external PWM control Vin = 440VAC PWM frequency = 4kHz, fo=60Hz, TA = 40°C, Rth SA = 0.075 °C/W Voltage Nominal Motor hp (kW) Nominal Motor Current DC Link DC link voltage Control Power Control Inputs PWM input signals IN1 - IN6 Input resistance IN1 - IN6 Pulse deadtime Minimum input pulse duration Maximum pulse duration for each upper IGBT RESET SFT CHG 850V maximum 15V ±5%, 200mA positive supply 15V ±5%, 10mA, negative supply 15V, 10mA, ±10% (max rise/fall time 150nsec) 720Ω ±5% 2.5 µsecs, minimum 1.0 µsec 20ms 15V active high, CMOS input (min duration 1µsec) 2 mA pull-down to energize relay (overrides internal control) 65A peak, ±10% 100°C, ±5% 40A peak, ±10% 1.5 µsec typical 100mV/A ±10% max. DC offset 200mV active high, 15V CMOS active high, 15V CMOS 15V high 4.7k pull-up,