For 29 years Qmax Systems has designed power conversion, distribution and storage hardware — from architecture and topology selection through magnetics, busbar and interconnect design, thermal simulation, high-voltage safety and protection coordination, PCB layout, bring-up and certification, to volume production.
Power electronics fails physically, not logically. A schematic can be electrically correct and the product still fail because the busbar runs hot, the creepage distance was short at altitude, the switching loop rings into the gate drive, or the protection did not discriminate and a single fault took down the whole branch. Those are decisions made in the copper, the stack-up and the clearance table — and they are resolved in simulation and layout, before the first board is fabricated.
The work spans a wide range: 48 V BLDC drives and 12-cell balancers at one end, and 3 kV / 100 A power modules, 300 kW SiC inverters, 800 V on-board chargers and UL-certified 45 kW rack PDUs shipped in the hundreds at the other. Every program is owned by senior engineers from architecture through manufacturing handover, and you own 100% of the resulting intellectual property at every milestone.
Topology selection, loss and efficiency budget, device and thermal sizing
Switching stage, isolated gate drive, feedback loop compensation
Custom inductors and transformers, core, winding and litz selection
Laminated busbars, current collectors, heavy copper and terminations
Forced air, cold plates, IMS substrates, custom heat sinks, via arrays
Insulation coordination, creepage, discrimination, active discharge
Conducted and radiated emissions, filter and snubber design in-house
UL program management, test jigs, calibration and volume transfer
The physical power path inside a pack and a rack — where the current actually flows, and where the heat and the hazard live.
Distributing power while measuring and controlling it at the level of the individual outlet or branch, with protection that discriminates.
Traction, charging and drive electronics built to survive automotive thermal cycling, vibration and EMC, then qualified for volume.
Conversion where every point of efficiency shows up as heat you would otherwise have to remove, and as operating cost.
The control loop that has to be fast enough to regulate and stable enough not to oscillate into a load that keeps moving.
The three things that decide whether a power design survives its duty cycle, and none of them are visible on a schematic.
| Domain | Devices & Silicon | Ratings, Interfaces & Materials |
|---|---|---|
| Wide-Bandgap Switching | Silicon carbide MOSFETs, GaN FETs, IGBT modules; isolated gate drivers | 800 V and above DC bus, high dv/dt and di/dt management, snubber and loop-inductance control |
| Battery & BMS | High-voltage BMS stack controllers and power interfaces, cell balancing front ends | LiFePO4, Li-ion and lithium titanate; 48 V to 1000 V DC packs; CAN, RS-485, MODBUS |
| Metering & Measurement | ST STPM34 metering AFE, TI MSP430 metering SoCs, precision shunts | Per-outlet and polyphase voltage, current, power, power factor and energy to ~1% accuracy |
| Control & Telemetry | NXP i.MX6 and i.MX6ULL, ST SPC5 automotive MCUs, Microchip PIC18, ARM Cortex-M, FPGAs | Embedded Linux and RTOS, microsecond control loops, SNMP, CAN, dual-redundant Ethernet |
| Protection & Switchgear | Hydraulic-magnetic breakers, DC contactors, HV DC fuses, insulation monitoring devices | 1000 V DC class, pre-charge circuits, per-outlet electronic trip, interlock chains |
| Materials & Interconnect | Laminated copper busbars, IMS and high-Tg laminate, cold plates, custom heat sinks | Heavy copper stack-ups, thermal via arrays, creepage and clearance per IEC 60664-1 |
This is a vertical, 72-inch 0U rack-mount intelligent Power Distribution Unit on a mains-isolated three-board architecture, delivering 415 VAC, 45 kVA, 3-phase power to 30 individually metered and switched C13 outlets with ~1% accuracy. An embedded Linux processor bridges telemetry to a dual-redundant Ethernet network, enabling remote monitoring and switching.
View case studyThis is a high-voltage motor controller ECU built around a multi-phase IGBT/MOSFET power stage rated for 450V bulk capacitance, driving heavy-duty three-phase output terminals for traction or industrial motor loads. An onboard microcontroller and gate-driver circuitry manage switching and protection, with headers for CAN signaling and sensor feedback.
This is a dual-channel MPPT solar power management board that regulates and converts solar MPPT inputs and dual SMPS rails into a stable output feeding a battery expansion bank. It integrates PoE backhaul, standby/auto power-enable control, and an MCU-driven I2C monitoring interface for intelligent power routing and charge management off-grid.
Clearance and creepage are not clearances you check at the end — they are derived from working voltage, overvoltage category, pollution degree and altitude, and they constrain where every component can sit. We build that table first, to IEC 60664-1, and lay out against it.
Fitting a breaker is not protection. Protection is a coordinated set of devices where a fault trips the smallest one able to clear it, so the rest of the system stays up. That coordination is designed, then verified by test.
An ungrounded high-voltage DC bus will not blow a fuse on a first earth fault — it will simply sit there, degraded and undetected, until a second fault makes it dangerous. That is why insulation monitoring exists, and why interlocks are engineered rather than fitted.
Getting the standard right matters as much as passing it. A traction inverter, a rack PDU and a battery rack are governed by three different standards with three different insulation and protection philosophies. Establishing which applies is an architecture decision, taken at the start of the program.
| Equipment Class | Governing Standard | Scope |
|---|---|---|
| Insulation coordination — all classes | IEC 60664-1 | Clearance, creepage, pollution degree, overvoltage category |
| Adjustable-speed drives and motor controllers | IEC / EN 61800-5-1 | Electrical, thermal and energy safety |
| Power conversion equipment | IEC / EN 62477-1 | Safety of power electronic converter systems |
| ICT and data center equipment, including PDUs | UL / IEC 62368-1 | Hazard-based safety for audio, video and ICT equipment |
| Circuit breakers and supplementary protectors | UL 489, UL 1077, EN 60934 | Overcurrent protective device qualification |
| Battery systems for stationary and motive use | UL 1973 | Batteries for use in energy storage and light rail |
| Automotive electronics | CISPR 25 · AIS-004 (Part 3) · ISO 26262 | Vehicle EMC and functional safety with ASIL traceability |
| Immunity, all classes | IEC 61000-4 series | ESD, surge, electrical fast transient, dips and interruptions |
Qmax-designed products have completed formal certification to UL489 and UL1077 on the rack PDU program, ARAI for the automotive kneeling and levelling system, FCC Part 15 Class A and Class B, FCC Part 18 Class A for industrial RF, SAR, CE and UL safety listing. Qmax manages the certification program, holds the technical file and the test evidence, and has taken products through on first submission.
Most design houses stop at the board edge. We design the laminated busbars, the current collectors, the terminations and the interconnect that actually carry the current — because at hundreds of amperes the copper is the circuit, and a board designed in isolation from it will not hold its thermal budget.
High power is only half the claim. Our rack PDU program is UL489 and UL1077 certified with hundreds of units shipped; the bus levelling system is ARAI certified at 10,000 units. We manage the certification program, hold the technical file, and have taken products through on first submission.
Junction temperature is designed, not measured after the fact. Copper weight, thermal via arrays, IMS and high-Tg substrates, cold plates and custom heat sinks are selected against a simulated thermal budget with derating applied, so the first build runs inside its limits instead of revealing them.
We design discrimination, not just devices — so a fault trips the smallest protective element that can clear it and the rest of the system stays up. On the rack PDU that meant 40 A hydraulic-magnetic branch breakers coordinated against per-outlet electronic trips at 15 A, verified by test rather than assumed from datasheets.
Off-the-shelf magnetics constrain the converter around them. We design custom inductors and transformers — wound and planar, including planar windings realized in the PCB stack-up — specifying core material, winding geometry and litz-wire gauge against the switching frequency, core loss and leakage inductance the topology actually needs.
High-voltage mistakes are expensive to find late and dangerous to find in the field. Qmax operates ISO 9001 and ISO 13485 certified quality systems, with defined internal process steps and review gates built to catch errors before a design reaches fabrication.
A one-hour session with a Qmax Systems Senior Hardware Architect. Bring a converter that runs hot, a busbar you cannot cool, a clearance table that will not close in the enclosure you have, or protection that trips the wrong device. Practical and engineering-driven — no sales pitch. We can sign an NDA beforehand.
