Chinese variable frequency drive makers scaled up capacity through mid-2026, with one Tianjin-listed CNBM high-voltage VFD line posting 100,000 unit/month supply capability for 3.3 kV 400 kW inverter builds [S1].
Across low-voltage and high-voltage classes, four vendor clusters now anchor the global B2B catalog: CNBM (Okorder-listed), VEICHI (AC310), Shenzhen Soyan Technology, and the V5-H series high-performance vector line advertised on kitairu.net [S1][S2][S3][S4].
CNBM High-Voltage VFDs: 3.3 kV Class Output
CNBM's general-purpose high-voltage variable frequency drive line targets fan and pump loads at the 3.3 kV 400 kW node, with loading port Tianjin and minimum order quantity of 1 unit on the Okorder B2B listing dated 2026-07-30 [S1]. Payment terms are TT or LC, and the listed supply capability reaches 100,000 unit/month, a level that signals export-oriented assembly rather than bespoke engineering [S1]. The 3.3 kV class is typical for medium-voltage induction motors driving large centrifugal pumps, mine dewatering fans, and induced-draft boiler fans where direct-on-line starting would draw 5–7x rated current.
VEICHI AC310 Vector Platform
The VEICHI AC310 series uses field-oriented vector control and supports both asynchronous and synchronous motor control on a single hardware platform, with V/F, voltage-frequency separation, open-loop vector, closed-loop vector, speed, and torque modes selectable per load [S2]. Standard communication is MODBUS-RTU, with optional PROFIBUS-DP, CANopen, and PROFINET cards for PLC and DCS integration, including direct touch-screen interfacing on the same bus [S2]. Protection features documented by the vendor include output short-to-ground, internal buffer relay, fan drive circuit, external 24 VDC short-circuit, and motor overload protection, plus software undervoltage, overvoltage, overcurrent, and overexcitation suppression [S2]. The book-style narrow-body chassis design and three-coat PCB conformal coating target panel builders who need IP54-class cabinet density without external derating [S2].
Shenzhen Soyan: Bundled Power Quality Portfolio
Shenzhen Soyan Technology Co., Ltd. positions VFD, online UPS tower/rack, battery pack, solar inverter, and energy storage system as a single portfolio under ISO 9001 and CE quality system certifications, with SGS verification referenced on the corporate site [S3]. The vendor states a defect rate of less than 2% across its series and offers personalized product customization, a useful option for OEM skid builders who need non-standard I/O maps or pre-loaded parameter sets [S3]. Soyan's bundle approach is common among second-tier Chinese suppliers that want to ride the same procurement approval that a buyer already uses for uninterruptible power supply or inverter lines, and it is a different selling motion than the dedicated drive specialists [S3].
Vector Control Performance Numbers
The V5-H series vector control VFD, listed on kitairu.net on 2026-07-09, publishes the most concrete low-frequency torque figures seen in the current catalog sweep: vector-control mode 1 delivers 0.50 Hz / 180% rated startup torque with 1:100 speed range and ±0.5% speed stability; vector-control mode 2 (sensorless) delivers 0.25 Hz / 180% rated torque, 1:200 range, and ±0.2% precision, both with 150% rated torque sustained at low frequency [S4]. Acceptable voltage rails are 200–240 VAC, 380–480 VAC, and 525 VAC / 690 VAC, with a 1140 VAC variant for mine-face conveyors and large hoist drives [S4]. That voltage spread is the practical answer to the common procurement question of whether a single platform can serve both 400 V European panels and 690 V Middle-East pump skids, and the published numbers meet the typical 150% low-frequency torque demand for constant-torque conveyors, mixers, and extruders.
Application Map: Where Each Class Lands
Process engineers reading the four sources together see a clear fit-by-class pattern: 200–480 V low-voltage vector drives (AC310, V5-H) cover HVAC fans, screw compressors, plastic injection moulding, and textile lines; 525–690 V variants cover mining conveyors, cement mills, and large water-treatment blowers; 3.3 kV CNBM-class drives cover utility fans, large boiler FD/ID fans, and dewatering pumps at the 200–600 kW node [S1][S2][S4]. A useful comparison for sourcing: AC310 wins on synchronous reluctance and electric-spindle coverage, V5-H wins on explicit low-frequency torque numbers and the widest voltage rail including 1140 V, and CNBM wins on the 3.3 kV mid-voltage step where most general-purpose catalogues stop [S2][S4]. The same drive-motor pairings underpin a broader drive motor selection workflow, especially when specifying encoder feedback cards for closed-loop vector mode.
Selection Criteria and Sourcing Risks
For procurement, the four data points that matter most are voltage class match, low-frequency torque specification, communication protocol coverage, and certification scope, and any of the four cited suppliers can be eliminated on one of these without changing the others [S1][S2][S3][S4]. Buyers should demand the documented 0.25 Hz / 180% torque curve in writing for constant-torque loads, since marketing copy frequently quotes 0.5 Hz figures that fall short on slow-speed extruders and crane hoist drives [S4]. Communication protocol mismatch is the second-most-common rework cause: an AC310 ordered without the PROFINET card cannot be field-upgraded to PROFINET on every firmware revision, so protocol selection belongs in the RFQ, not the commissioning punch-list [S2]. Finally, where the same cabinet feeds a variable speed drive and a downstream process line, the related work on machine tool process control instrumentation stacks shows the same Chinese-vendor tier map and is a useful cross-reference for plant-engineering procurement teams.
Trackable signals for the next 90 days: watch for IEC 61800-9-1 energy-efficiency class declarations on new AC310 datasheet revisions, look for a 1140 V V5-H variant datasheet update that lists regenerative-braking module part numbers, and monitor Shenzhen Soyan for ESS-bundled VFD SKUs aimed at solar-pump integrators [S2][S3][S4].