BP7A-LS Powerex

First Release: February 1, 2005 Application NOTES: www.pwrx.com BP7A L-Series IPM Interface Circuit Reference Design Description: The BP7A is a complete isolated interface circuit for six and seven pack low and medium power L- Series IPMs. This circuit provides opto-coupled isolation for control signals and isolated power supplies for the IPMs built-in gate drive and protection circuits. The isolated interface helps to simplify prototype development and minimize design time by allowing direct connection of the IPM to logic level control circuits. Features: Applications: Complete three-phase isolated interface circuit with BP7A is designed for use with Powerex L-Series six brake control and fault feedback and seven pack IPMs: 50A-300A 600V and 25A- 150A 1200V. 2500VRMS isolation for control power and signals Standard AMP MTA .100 Input Signal and Control Use Powerex VLA106-24151 and VLA106- Power Connectors 24154 DC to DC converters for isolated Operates from a single 24VDC supply control power. See Table 1 for Compact Size 4.7 x 2.9 (73mm x 119mm) requirements. Ordering Information: BP7A-LS is a kit containing a bare PCB and four VLA106-24151 DC to DC converters (For use with L-Series IPMs in package A and B) BP7A-LB is a kit containing a bare PCB with three VLA106-24151 DC to DC converters and one VLA106-24154 DC to DC converter (For use with L-Series IPMs in package C) BP7A is a bare PCB only. Note: User must supply Opto-Couplers and passive components to fully populate the BP7A (See Table 2) 1 Table 1: L-Series IPM Line-Up and Interface Circuit Selection Figure 1: L-Series IPMs Voltage Current Recomm ended Re fe re nce Part Num ber Package (V) (A) DC to DC Converters Des ign PM50( )L(*)060 50 PM75( )L(*)060 75 A or B VLA106-24151 x 4pc. PM100( )L(*)060 100 BP7A PM150( )L(*)060 150 600 Package A PM200( )LA060 200 VLA106-24151 x 3pc. C VLA106-24154 x 1pc. PM300( )LA060 300 PM450CLA060 450 D VLA106-24151 x 6pc. BP6A PM600CLA060 600 PM25( )L(*)120 25 A or B VLA106-24151 x 4pc. PM50( )L(*)120 50 BP7A PM75( )L(*)120 75 Package B PM100( )LA120 100 VLA106-24151 x 3pc. 1200 C VLA106-24154 x 1pc. PM150( )LA120 150 PM200CLA120 200 D VLA106-24151 x 6pc. BP6A PM300CLA120 300 PM450CLA120 450 (*) Package Option: B=Solder pin, A=Screw terminal ( ) Circuit Option: R=Six Pack+Brake, C=Six pack Example: PM75RLB120 is a 75A, 1200V six pack with brake in a solder pin package Package C Overview: A significant advantage provided by the L-Series IPMs built- in gate drive and protection circuits is that the entire family outlined in Table 1 requires only two different interface circuit designs. The standard interface circuit consists of opto-couplers to transfer control signals and isolated power supplies to power the IPMs internal circuits. The two circuits are similar except that devices in packages A, B, and C have a common control ground for all three low side IGBTs. This permits use of a single low side supply so that only four isolated supplies are required. The Powerex BP7A reference design is an example of this circuit. The remaining large L-Series IPMs in Package D package D utilize separate control grounds on the low side to minimize ground bounce induced noise. As a result these devices require six isolated power supplies. Interface circuit details for these devices are available in the Powerex BP6A reference design application note. Isolated DC to DC Converters: In order to simplify the design and layout of the required control power supplies Powerex has introduced the VLA106-24151 and VLA106-24154 isolated DC to DC converters shown in figure 2. Both DC to DC converters are designed to operate from a 24V DC supply and produce an isolated 15V DC output. The VLA106-24151 provides up to 100mA and the VLA106-24154 provides up to 300mA for control power. Both DC to DC converters use transformers to provide 2500VRMS isolation between the primary and secondary side. The BP7A board uses three VLA106-24151 DC to DC converters to provide high side control power for the L- Series IPMs. The low side control power can be supplied by either a VLA106-24151 or VLA106-24154. The higher current VLA106-24154 is only needed for low side control power on the package C IPMs when the current draw of the three low side gate drive circuits exceeds 100mA. Table 1 shows the recommended DC to DC converters for each L-Series IPM. 2